Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2018	Oct. 22, 2018
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q3
Entity Current Reporting Status	Yes
Entity Registrant Name	WASTE MANAGEMENT INC
Entity Central Index Key	0000823768
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		426,347,027

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 83	$ 22
Accounts receivable, net of allowance for doubtful accounts of $25 and $21, respectively	1,943	1,805
Other receivables	399	569
Parts and supplies	103	96
Other assets	147	132
Total current assets	2,675	2,624
Property and equipment, net of accumulated depreciation and amortization of $18,174 and $17,704, respectively	11,815	11,559
Goodwill	6,390	6,247
Other intangible assets, net	554	547
Restricted trust and escrow accounts	394	319
Investments in unconsolidated entities	419	269
Other assets	344	264
Total assets	22,591	21,829
Current liabilities:
Accounts payable	940	1,040
Accrued liabilities	1,171	980
Deferred revenues	512	503
Current portion of long-term debt	447	739
Total current liabilities	3,070	3,262
Long-term debt, less current portion	9,569	8,752
Deferred income taxes	1,245	1,248
Landfill and environmental remediation liabilities	1,832	1,770
Other liabilities	634	755
Total liabilities	16,350	15,787
Commitments and contingencies
Waste Management, Inc. stockholders' equity:
Common stock, $0.01 par value; 1,500,000,000 shares authorized; 630,282,461 shares issued	6	6
Additional paid-in capital	4,927	4,933
Retained earnings	9,464	8,588
Accumulated other comprehensive income (loss)	(16)	8
Treasury stock at cost, 203,157,357 and 196,963,558 shares, respectively	(8,142)	(7,516)
Total Waste Management, Inc. stockholders' equity	6,239	6,019
Noncontrolling interests	2	23
Total equity	6,241	6,042
Total liabilities and equity	$ 22,591	$ 21,829

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
CONDENSED CONSOLIDATED BALANCE SHEETS
Allowance for doubtful accounts	$ 25	$ 21
Accumulated depreciation and amortization	$ 18,174	$ 17,704
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	1,500,000,000	1,500,000,000
Common stock, shares issued	630,282,461	630,282,461
Treasury stock, shares	203,157,357	196,963,558

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS
Operating revenues	$ 3,822	$ 3,716	$ 11,072	$ 10,833
Costs and expenses:
Operating	2,373	2,302	6,870	6,758
Selling, general and administrative	345	356	1,083	1,099
Depreciation and amortization	376	350	1,107	1,034
Restructuring	1	(2)	4
(Gain) loss from divestitures, asset impairments and unusual items, net	28	9	(14)	10
Total costs and expenses	3,123	3,015	9,050	8,901
Income from operations	699	701	2,022	1,932
Other income (expense):
Interest expense, net	(93)	(90)	(277)	(272)
Equity in net losses of unconsolidated entities	(9)	(8)	(29)	(53)
Other, net			1
Total other income (expense)	(102)	(98)	(305)	(325)
Income before income taxes	597	603	1,717	1,607
Income tax expense	99	215	325	561
Consolidated net income	498	388	1,392	1,046
Less: Net income (loss) attributable to noncontrolling interests	(1)	2	(2)
Net income attributable to Waste Management, Inc.	$ 499	$ 386	$ 1,394	$ 1,046
Basic earnings per common share	$ 1.16	$ 0.88	$ 3.24	$ 2.37
Diluted earnings per common share	1.16	0.87	3.22	2.36
Cash dividends declared per common share	$ 0.465	$ 0.425	$ 1.395	$ 1.275

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Consolidated net income	$ 498	$ 388	$ 1,392	$ 1,046
Derivative instruments, net	2	2	6	6
Available-for-sale securities, net	9		8	2
Foreign currency translation adjustments	22	46	(33)	86
Post-retirement benefit obligation, net		(1)
Other comprehensive income (loss), net of tax	33	47	(19)	94
Comprehensive income	531	435	1,373	1,140
Less: Comprehensive income (loss) attributable to noncontrolling interests	(1)	2	(2)
Comprehensive income attributable to Waste Management, Inc.	$ 532	$ 433	$ 1,375	$ 1,140

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash flows from operating activities:
Consolidated net income	$ 1,392	$ 1,046
Adjustments to reconcile consolidated net income to net cash provided by operating activities:
Depreciation and amortization	1,107	1,034
Deferred income tax benefit	(32)	(46)
Interest accretion on landfill liabilities	71	68
Provision for bad debts	35	31
Equity-based compensation expense	63	74
Net gain on disposal of assets	(21)	(7)
(Gain) loss from divestitures, asset impairments and unusual items, net	(14)	38
Equity in net losses of unconsolidated entities, net of dividends	29	25
Change in operating assets and liabilities, net of effects of acquisitions and divestitures:
Receivables	43	112
Other current assets	(22)	(25)
Other assets	(3)	(2)
Accounts payable and accrued liabilities	177	105
Deferred revenues and other liabilities	(167)	(65)
Net cash provided by operating activities	2,658	2,388
Cash flows from investing activities:
Acquisitions of businesses, net of cash acquired	(342)	(78)
Capital expenditures	(1,240)	(981)
Proceeds from divestitures of businesses and other assets (net of cash divested)	106	19
Other, net	(30)	(10)
Net cash used in investing activities	(1,506)	(1,050)
Cash flows from financing activities:
New borrowings	174	197
Debt repayments	(338)	(749)
Net commercial paper borrowings	523	501
Common stock repurchase program	(750)	(750)
Cash dividends	(605)	(566)
Exercise of common stock options	45	92
Tax payments associated with equity-based compensation transactions	(28)	(47)
Other, net	(36)	(9)
Net cash used in financing activities	(1,015)	(1,331)
Effect of exchange rate changes on cash, cash equivalents and restricted cash and cash equivalents		1
Increase in cash, cash equivalents and restricted cash and cash equivalents	137	8
Cash, cash equivalents and restricted cash and cash equivalents at beginning of period	293	94
Cash, cash equivalents and restricted cash and cash equivalents at end of period	$ 430	$ 102

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2018	Sep. 30, 2017
Reconciliation of cash, cash equivalents and restricted cash and cash equivalents at end of period
Cash and cash equivalents	$ 83	$ 35
Restricted cash and cash equivalents included in restricted trust and escrow accounts	347	67
Cash, cash equivalents and restricted cash and cash equivalents at end of period	$ 430	$ 102

CONDENSED CONSOLIDATED STATEMENT OF CHANGES IN EQUITY - 9 months ended Sep. 30, 2018 - USD ($) shares in Thousands, $ in Millions	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Treasury Stock [Member]	Noncontrolling Interests [Member]	Total
Beginning balance at Dec. 31, 2017	$ 6	$ 4,933	$ 8,588	$ 8	$ (7,516)	$ 23	$ 6,042
Beginning balance, shares at Dec. 31, 2017	630,282				(196,964)
Equity roll forward
Adoption of new accounting standards			85	(5)			80
Consolidated net income			1,394			(2)	1,392
Other comprehensive income (loss), net of tax				(19)			(19)
Cash dividends			(605)				(605)
Equity-based compensation transactions, net		34	2		$ 84		120
Equity-based compensation transaction, shares					2,181
Common stock repurchase program		(40)			$ (710)		(750)
Common stock repurchase program, shares					(8,375)
Divestiture of noncontrolling interest						(19)	(19)
Other, net, shares					1
Ending balance at Sep. 30, 2018	$ 6	$ 4,927	$ 9,464	$ (16)	$ (8,142)	$ 2	$ 6,241
Ending balance, shares at Sep. 30, 2018	630,282				(203,157)

Basis of Presentation

9 Months Ended

Sep. 30, 2018

Basis of Presentation

Basis of Presentation

1. Basis of Presentation

The financial statements presented in this report represent the consolidation of Waste Management, Inc., a Delaware corporation; its wholly-owned and majority-owned subsidiaries; and certain variable interest entities for which Waste Management, Inc. or its subsidiaries are the primary beneficiaries as described in Note 14. Waste Management, Inc. is a holding company and all operations are conducted by its subsidiaries. When the terms “the Company,” “we,” “us” or “our” are used in this document, those terms refer to Waste Management, Inc., its consolidated subsidiaries and consolidated variable interest entities. When we use the term “WM,” we are referring only to Waste Management, Inc., the parent holding company.

We are North America’s leading provider of comprehensive waste management environmental services. We partner with our residential, commercial, industrial and municipal customers and the communities we serve to manage and reduce waste at each stage from collection to disposal, while recovering valuable resources and creating clean, renewable energy. Our “Solid Waste” business is operated and managed locally by our subsidiaries that focus on distinct geographic areas and provides collection, transfer, disposal, and recycling and resource recovery services. Through our subsidiaries, we are also a leading developer, operator and owner of landfill gas-to-energy facilities in the United States (“U.S.”).

We evaluate, oversee and manage the financial performance of our Solid Waste business subsidiaries through our 17 Areas. We also provide additional services that are not managed through our Solid Waste business, which are presented in this report as “Other.” Additional information related to our segments is included in Note 8.

The Condensed Consolidated Financial Statements as of September 30, 2018 and for the three and nine months ended September 30, 2018 and 2017 are unaudited. In the opinion of management, these financial statements include all adjustments, which, unless otherwise disclosed, are of a normal recurring nature, necessary for a fair presentation of the financial position, results of operations, comprehensive income, cash flows, and changes in equity for the periods presented. The results for interim periods are not necessarily indicative of results for the entire year. The financial statements presented herein should be read in conjunction with the financial statements included in our Annual Report on Form 10‑K for the year ended December 31, 2017.

In preparing our financial statements, we make numerous estimates and assumptions that affect the accounting for and recognition and disclosure of assets, liabilities, equity, revenues and expenses. We must make these estimates and assumptions because certain information that we use is dependent on future events, cannot be calculated with precision from available data or simply cannot be calculated. In some cases, these estimates are difficult to determine, and we must exercise significant judgment. In preparing our financial statements, the most difficult, subjective and complex estimates and the assumptions that present the greatest amount of uncertainty relate to our accounting for landfills, environmental remediation liabilities, long-lived asset impairments and reserves associated with our insured and self-insured claims. Actual results could differ materially from the estimates and assumptions that we use in the preparation of our financial statements.

Adoption of New Accounting Standards

Revenue Recognition — In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014-09 associated with revenue recognition. On January 1, 2018, we adopted ASU 2014-09 using the modified retrospective approach for all ongoing customer contracts. Our results of operations for the reported periods after January 1, 2018 are presented under this amended guidance, while prior period amounts are not adjusted and continue to be reported in accordance with historical accounting guidance.

The impact of adopting the amended guidance primarily relates to (i) the deferral of certain sales incentives, which previously were expensed as incurred, but under the new guidance are capitalized as other assets and amortized to selling, general and administrative expenses over the expected life of the customer relationship and (ii) the recognition of certain consideration payable to our customers as a reduction in operating revenues, which under historical guidance was recorded as operating expenses. We recognized a net $80 million increase to our retained earnings as of January 1, 2018 for the cumulative impact of adopting the amended guidance associated with the capitalization of sales incentives as contract acquisition costs consisting of a $108 million asset and a related $28 million deferred tax liability. There were no material impacts on our consolidated financial statements, which include these changes, as a result of our adoption of this amended guidance.

For contracts with an effective term greater than one year, we applied the standard’s practical expedient that permits the exclusion of unsatisfied performance obligations as our right to consideration corresponds directly to the value provided to the customer for services completed to date and all future variable consideration is allocated to wholly unsatisfied performance obligations. We also applied the standard’s optional exemption for performance obligations related to contracts that have an original expected duration of one year or less. See Note 4 for additional information and disclosures related to this amended guidance.

Financial Instruments — In January 2016, the FASB issued ASU 2016‑01 associated with the recognition and measurement of financial assets and liabilities with further clarifications made in February 2018 with the issuance of ASU 2018-03. The amended guidance requires certain equity investments that are not consolidated and not accounted for under the equity method to be measured at fair value with changes in fair value recognized in net income rather than as a component of accumulated other comprehensive income (loss). It further states that an entity may choose to measure equity investments that do not have readily determinable fair values using a quantitative approach, or measurement alternative, which is equal to its cost minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer. The Company adopted this amended guidance on January 1, 2018 using a prospective transition approach, which did not have an impact on our consolidated financial statements.

We concluded that all equity investments within the scope of ASU 2016-01, which primarily relate to equity securities previously accounted for under the cost method, do not have readily determinable fair values. Accordingly, the value of these investments beginning January 1, 2018 has been measured using a quantitative approach, or the measurement alternative, as noted above. As of September 30, 2018, the carrying amount of our investments without readily determinable fair values was $85 million. During the three and nine months ended September 30, 2018, we did not recognize any impairments or other adjustments related to these investments.

Statement of Cash Flows — In August 2016, the FASB issued ASU 2016‑15 associated with the classification of certain cash receipts and cash payments in the statement of cash flows. In November 2016, the FASB issued ASU 2016‑18 associated with the presentation of restricted cash and cash equivalents in the statement of cash flows. The objective of the amended guidance was to reduce existing diversity in practice. This amended guidance was retrospectively adopted on January 1, 2018 and required the following disclosures and changes to the presentation of our financial statements:

Cash, cash equivalents and restricted cash and cash equivalents reported on the Condensed Consolidated Statements of Cash Flows now includes restricted cash and cash equivalents of $62 million, $67 million and $271 million as of December 31, 2016, September 30, 2017 and December 31, 2017, respectively, in restricted trust and escrow accounts in our Condensed Consolidated Balance Sheets as well as previously reported cash and cash equivalents.

Cash payments made within 120 days of the acquisition date of a business combination to settle a contingent consideration liability are classified as cash outflows from investing activities. Thereafter, cash payments up to the amount of the contingent consideration liability recognized at the acquisition date (including measurement-period adjustments) are classified as cash outflows from financing activities and any excess is classified as cash outflows from operating activities. The adoption of this amended guidance did not have a material impact on our Condensed Consolidated Statements of Cash Flows.

Our restricted cash and cash equivalents generally consist of funds deposited into specific accounts for purposes of funding insurance claims and demonstrating our ability to meet our landfill final capping, closure, post-closure and environmental remediation obligations.

Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income — In February 2018, the FASB issued ASU 2018-02 associated with the reclassification of certain tax effects from accumulated other comprehensive income (loss). This amended guidance allows a reclassification from accumulated other comprehensive income (loss) to retained earnings for stranded tax effects resulting from the Tax Cuts and Jobs Act (the “Act”) which was signed into law on December 22, 2017. We early adopted this amended guidance on January 1, 2018, and as a result, elected to reclassify $5 million of stranded tax effects from accumulated other comprehensive income (loss) to retained earnings using a specific identification approach. See Note 11 for additional disclosures related to this amended guidance.

Income Taxes — In March 2018, the FASB issued ASU 2018-05 associated with the accounting and disclosures around the enactment of the Act and the Securities and Exchange Commission’s Staff Accounting Bulletin No. 118, Income Tax Accounting Implications of the Tax Cuts and Jobs Act (“SAB 118”), which the Company has adopted. See Note 5 for the disclosures related to this amended guidance.

New Accounting Standards Pending Adoption

Financial Instrument Credit Losses — In June 2016, the FASB issued ASU 2016‑13 associated with the measurement of credit losses on financial instruments. The amended guidance replaces the current incurred loss impairment methodology of recognizing credit losses when a loss is probable, with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to assess credit loss estimates. The amended guidance is effective for the Company on January 1, 2020, with early adoption permitted beginning January 1, 2019. We are assessing the provisions of this amended guidance and evaluating the impact on our consolidated financial statements.

Leases — In February 2016, the FASB issued ASU 2016‑02 associated with lease accounting. There have been further amendments, including practical expedients, with the issuance of ASU 2018-01 and ASU 2018-11 in January 2018 and July 2018, respectively. The amended guidance requires the recognition of lease assets and lease liabilities on the balance sheet for those leases with terms in excess of 12 months and currently classified as operating leases. Disclosure of key information about leasing arrangements will also be required. The amended guidance is effective for the Company on January 1, 2019. To date, we have performed the following activities related to the adoption of the standard: (i) formed an implementation work team; (ii) performed training for the various organizations that will be most affected by the new standard; (iii) elected our practical expedients, including our transition method; (iv) acquired a software solution to manage and account for leases under the new standard and (v) identified our initial lease population that will be impacted by the new standard. We continue to evaluate the impact of this amended guidance on our consolidated financial statements.

Reclassifications

When necessary, reclassifications have been made to our prior period financial information to conform to the current year presentation.

Landfill and Environmental Remediation Liabilities

9 Months Ended

Sep. 30, 2018

Landfill and Environmental Remediation Liabilities

Landfill and Environmental Remediation Liabilities

2. Landfill and Environmental Remediation Liabilities

Liabilities for landfill and environmental remediation costs are presented in the table below (in millions):


	September 30, 2018						December 31, 2017
			Environmental						Environmental
	Landfill		Remediation		Total		Landfill		Remediation		Total
Current (in accrued liabilities)	$	131	$	27	$	158	$	128	$	28	$	156
Long-term		1,622		210		1,832		1,547		223		1,770
	$	1,753	$	237	$	1,990	$	1,675	$	251	$	1,926

The changes to landfill and environmental remediation liabilities for the nine months ended September 30, 2018 are reflected in the table below (in millions):


			Environmental
	Landfill		Remediation
December 31, 2017	$	1,675	$	251
Obligations incurred and capitalized		62		—
Obligations settled		(71)		(18)
Interest accretion		71		4
Revisions in estimates and interest rate assumptions (a) (b)		7		2
Acquisitions, divestitures and other adjustments		9		(2)
September 30, 2018	$	1,753	$	237

(a)

The amount reported for our landfill liabilities includes an increase of $11 million due to the acceleration of the expected timing of capping activities for a landfill. See Note 10 for discussion of the impairment charge related to this landfill.

(b)

The amount reported for our environmental remediation liabilities includes the impact of an increase in the risk-free discount rate used to measure our liabilities from 2.5% at December 31, 2017 to 3.0% at September 30, 2018, resulting in a decrease of $5 million to our environmental remediation liabilities.

At several of our landfills, we provide financial assurance by depositing cash into restricted trust funds or escrow accounts for purposes of demonstrating our ability to meet our final capping, closure, post-closure and environmental remediation obligations. Generally, these trust funds are established to comply with statutory requirements and operating agreements. See Note 14 for additional information related to these trusts.

Debt

9 Months Ended

Sep. 30, 2018

Debt

Debt

3. Debt

The following table summarizes the major components of debt as of each balance sheet date (in millions) and provides the maturities and interest rate ranges of each major category as of September 30, 2018:


	September 30,		December 31,
	2018		2017
Revolving credit facility (weighted average interest rate of 2.7% as of September 30, 2018)	$	44	$	—
Commercial paper program (weighted average interest rate of 2.4% as of September 30, 2018 and 1.9% as of December 31, 2017)		1,053		515
Canadian term loan and revolving credit facility (weighted average effective interest rate of 2.5% as of December 31, 2017)		—		113
Senior notes, maturing through 2045, interest rates ranging from 2.4% to 7.75% (weighted average interest rate of 4.3% as of September 30, 2018 and December 31, 2017)		6,222		6,222
Tax-exempt bonds, maturing through 2045, fixed and variable interest rates ranging from 1.35% to 4.3% (weighted average interest rate of 2.2% as of September 30, 2018 and 2.0% as of December 31, 2017)		2,318		2,370
Capital leases and other, maturing through 2040, interest rates up to 12%		431		327
Debt issuance costs, discounts and other		(52)		(56)
		10,016		9,491
Current portion of long-term debt		447		739
	$	9,569	$	8,752

Debt Classification

As of September 30, 2018, we had $2.2 billion of debt maturing within the next 12 months, including (i) $1.1 billion of short-term borrowings under our commercial paper program; (ii) $806 million of tax-exempt bonds with term interest rate periods that expire within the next 12 months, which is prior to their scheduled maturities; (iii) $260 million of other debt with scheduled maturities within the next 12 months, including $209 million of tax-exempt bonds and (iv) C$57 million, or $44 million, of Canadian borrowings under our long-term U.S. and Canadian revolving credit facility (“$2.75 billion revolving credit facility”). Of the $1.1 billion of short-term borrowings outstanding under our commercial paper program as of September 30, 2018 that are supported by our $2.75 billion revolving credit facility, we have the intent and ability to refinance or maintain $955 million of these borrowings on a long-term basis, and we have classified these amounts as long-term debt. As of September 30, 2018, we have classified an additional $761 million of debt as long-term because we have the intent and ability to refinance these borrowings on a long-term basis as supported by the forecasted available capacity under our $2.75 billion revolving credit facility, as discussed below. The remaining $447 million is classified as current obligations.

As of September 30, 2018, we also have $268 million of variable-rate tax-exempt bonds that are supported by letters of credit under our $2.75 billion revolving credit facility. The interest rates on our variable-rate tax-exempt bonds are generally reset on either a daily or weekly basis through a remarketing process. All recent tax-exempt bond remarketings have successfully placed Company bonds with investors at market-driven rates and we currently expect future remarketings to be successful. However, if the remarketing agent is unable to remarket our bonds, the remarketing agent can put the bonds to us. In the event of a failed remarketing, we have the availability under our $2.75 billion revolving credit facility to fund these bonds until they are remarketed successfully. Accordingly, we have also classified these borrowings as long-term in our Condensed Consolidated Balance Sheet as of September 30, 2018.

Access to and Utilization of Credit Facilities and Commercial Paper Program

$2.75 Billion Revolving Credit Facility — In June 2018, we entered into the $2.75 billion revolving credit facility, which amended and restated our prior long-term U.S. revolving credit facility. Amendments to the credit agreement included (i) increasing total capacity under the facility from $2.25 billion to $2.75 billion; (ii) establishment of a $750 million accordion feature that may be used to increase total capacity in future periods; (iii) extending the term through June 2023 and (iv) inclusion of two one-year extension options. Waste Management of Canada Corporation and WM Quebec Inc., each an indirect wholly-owned subsidiary of WM, were added as additional borrowers under the $2.75 billion revolving credit facility, and the agreement permits borrowing in Canadian dollars up to the U.S. dollar equivalent of $375 million, with such borrowings to be repaid in Canadian dollars. Waste Management Holdings, Inc., a wholly-owned subsidiary of WM, guarantees all of the obligations under the $2.75 billion revolving credit facility.

The $2.75 billion revolving credit facility provides us with credit capacity to be used for either cash borrowings or to support letters of credit or commercial paper. The rates we pay for outstanding U.S. or Canadian loans are generally based on LIBOR or CDOR, respectively, plus a spread depending on the Company’s debt rating assigned by Moody’s Investors Service and Standard and Poor’s. As of September 30, 2018, we had C$57 million, or $44 million, of outstanding borrowings under this facility. We had $606 million of letters of credit issued and $1.1 billion of outstanding borrowings under our commercial paper program, both supported by this facility, leaving unused and available credit capacity of $1.0 billion as of September 30, 2018.

Commercial Paper Program — We have a commercial paper program that enables us to borrow funds for up to 397 days at competitive interest rates. The commercial paper program is fully supported by our $2.75 billion revolving credit facility. In June 2018, we amended our commercial paper program, increasing our ability to borrow funds from $1.5 billion to $2.75 billion, provided that the aggregate outstanding amount of commercial paper borrowings, together with borrowings and issued letters of credit under the $2.75 billion revolving credit facility, shall not at any time exceed the aggregate authorized borrowing capacity of such facility. As of September 30, 2018, we had $1.1 billion of outstanding borrowings under our commercial paper program.

Canadian Term Loan and Revolving Credit Facility — In August 2018, we terminated our Canadian credit agreement, as discussed further below. Prior to its termination, the Canadian credit agreement provided the Company with (i) C$50 million of revolving credit capacity to be used for borrowings or letters of credit and (ii) C$460 million of non-revolving term credit that was prepayable without penalty.

Other Letter of Credit Facilities — As of September 30, 2018, we utilized $541 million of other letter of credit facilities, which are both committed and uncommitted, with terms maturing through September 2019.

Debt Borrowings and Repayments

Revolving Credit Facility — During the first half of 2018, we borrowed and repaid $28 million under our revolving credit facility, which we amended and restated in June 2018, as discussed above. During the third quarter of 2018, we had net cash Canadian borrowings of C$57 million, or $44 million, under our $2.75 billion revolving credit facility, all of which was used to repay the remaining balance under our Canadian term loan, as discussed below.

Commercial Paper Program — During the nine months ended September 30, 2018, we had net cash borrowings of $523 million to support new business opportunities and for general corporate purposes.

Canadian Term Loan and Revolving Credit Facility — Through August 2018, we repaid the remaining balance of C$142 million, or $109 million, owed under our Canadian term loan and revolving credit facility and subsequently terminated our Canadian credit agreement. The remaining change in the carrying value of outstanding borrowings under our Canadian term loan and revolving credit facility is due to foreign currency translation.

Tax-Exempt Bonds — During the nine months ended September 30, 2018, we repaid $52 million of our tax-exempt bonds with available cash.

Capital Leases and Other — The increase in our capital leases and other debt obligations during the nine months ended September 30, 2018 is primarily related to our new federal low-income housing investment discussed in Note 5, which increased our debt obligations by $139 million. This increase was offset by a net decrease of $35 million, primarily due to divestitures and net cash repayments of debt at maturity.

Operating Revenues	9 Months Ended
Operating Revenues	Sep. 30, 2018
Operating Revenues
Operating Revenues	4. Operating Revenues Our Solid Waste operating revenues are primarily generated from fees charged for our collection, transfer, disposal, and recycling and resource recovery services, and from sales of commodities by our recycling and landfill gas-to-energy operations. Revenues from our collection operations are influenced by factors such as collection frequency, type of collection equipment furnished, type and volume or weight of the waste collected, distance to the disposal facility or material recovery facility and our disposal costs. Revenues from our landfill operations consist of tipping fees, which are generally based on the type and weight or volume of waste being disposed of at our disposal facilities. Fees charged at transfer stations are generally based on the weight or volume of waste deposited, taking into account our cost of loading, transporting and disposing of the solid waste at a disposal site. Recycling revenues generally consist of tipping fees and the sale of recycling commodities to third parties. The fees we charge for our services generally include our environmental fee, fuel surcharge and regulatory recovery fee, which are intended to pass through to customers direct and indirect costs incurred. We also provide additional services that are not managed through our Solid Waste business, including operations managed by both our Strategic Business Solutions (“WMSBS”) and Energy and Environmental Services (“EES”) organizations, recycling brokerage services, landfill gas-to-energy services and certain other expanded service offerings and solutions. Our revenue from sources other than customer contracts primarily relates to lease revenue associated with compactors and balers. Revenue from these leasing arrangements was not material and represented approximately 1% of total revenue for each of the reported periods. See Note 8 for additional information related to revenue by reportable segment and major lines of business. Revenue Recognition We generally recognize revenue as services are performed or products are delivered. For example, revenue typically is recognized as waste is collected, tons are received at our landfills or transfer stations, or recycling commodities are collected or delivered as product. We bill for certain services prior to performance. Such services include, among others, certain commercial and residential contracts and equipment rentals. These advance billings are included in deferred revenues and recognized as revenue in the period service is provided. Accounts Receivable Accounts receivable, which are recorded when billed, when services are performed or when cash is advanced, are claims against third parties that will generally be settled in cash. The carrying value of our receivables, net of the allowance for doubtful accounts, represents the estimated net realizable value. We estimate our allowance for doubtful accounts based on historical collection trends; type of customer, such as municipal or commercial; the age of outstanding receivables and existing economic conditions. If events or changes in circumstances indicate that specific receivable balances may be impaired, further consideration is given to the collectability of those balances and the allowance is adjusted accordingly. Past-due receivable balances are written off when our internal collection efforts have been unsuccessful. Deferred Revenues We record deferred revenues when cash payments are received or due in advance of our performance and classify them as current since they are earned within a year and there are no significant financing components. Substantially all our deferred revenues during the reported periods are realized as revenues within one to three months, when the related services are performed. Contract Acquisition Costs Our incremental direct costs of obtaining a contract, which consist primarily of sales incentives, are generally deferred and amortized to selling, general and administrative expense over the estimated life of the relevant customer relationship, ranging from 5 to 13 years. Contract acquisition costs that are paid to the customer are deferred and amortized as a reduction in revenue over the contract life. Our contract acquisition costs are classified as current or noncurrent based on the timing of when we expect to recognize amortization and are included in other assets in our Condensed Consolidated Balance Sheet. As of September 30, 2018, we had $141 million of deferred contract costs, of which $109 million was related to deferred sales incentives. During the three and nine months ended September 30, 2018, we amortized $6 million and $17 million of sales incentives to selling, general and administrative expense, and $8 million and $27 million of other contract acquisition costs as a reduction in revenue, respectively. Long-Term Contracts Approximately 30% of our total revenue is derived from contracts with an effective term greater than one year. The consideration for these contracts is variable in nature. The variable elements of these contracts primarily include the number of homes and businesses served and annual rate changes based on consumer price index, fuel prices or other operating costs. Such contracts are generally within our collection, recycling and other lines of business and have a weighted average remaining contract life of approximately four years. We do not disclose the value of unsatisfied performance obligations for these contracts as our right to consideration corresponds directly to the value provided to the customer for services completed to date and all future variable consideration is allocated to wholly unsatisfied performance obligations.

Income Taxes	9 Months Ended
Income Taxes	Sep. 30, 2018
Income Taxes
Income Taxes	5. Income Taxes Our effective income tax rate for the three and nine months ended September 30, 2018 was 16.6% and 18.9%, respectively, compared with 35.7% and 34.9%, respectively, for the comparable prior year periods. We evaluate our effective income tax rate at each interim period and adjust it as facts and circumstances warrant. The decrease in the effective income tax rate for the three and nine months ended September 30, 2018, compared with the prior year periods, was primarily due to the enactment of tax reform, as discussed below. The difference between federal income taxes computed at the federal statutory rate and reported income taxes for the three and nine months ended September 30, 2018 was primarily due to a reduction in income tax expense related to (i) adjustments to our accruals and related deferred taxes due to the filing of our 2017 income tax returns and changes in state laws; (ii) federal tax credits and (iii) impacts of enactment of tax reform offset, in part, by the unfavorable impact of state and local income taxes. The nine-month period was also favorably impacted by tax audit settlements. The difference between federal income taxes computed at the federal statutory rate and reported income taxes for the three months ended September 30, 2017 was primarily due to the unfavorable impact of state and local income taxes offset, in part, by the favorable impact of federal tax credits and adjustments to our accruals and related deferred taxes due to the filing of our 2016 income tax returns. The difference between federal income taxes computed at the federal statutory rate and reported income taxes for the nine months ended September 30, 2017 was primarily due to the favorable impact of federal tax credits, excess tax benefits related to equity-based compensation and adjustments to our accruals and related deferred taxes due to the filing of our 2016 income tax returns offset, in part, by the unfavorable impact of state and local income taxes and nondeductible impairments. Enactment of Tax Reform — The Act was signed into law on December 22, 2017. The most significant impacts of the Act to the Company include a reduction in the federal corporate income tax rate from 35% to 21%, effective January 1, 2018, and a one-time, mandatory transition tax on deemed repatriation of previously tax-deferred and unremitted foreign earnings. In accordance with ASU 2018-05 and SAB 118, the Company recognized the provisional tax impacts related to the remeasurement of our deferred income tax assets and liabilities and the one-time, mandatory transition tax on deemed repatriation during the year ended December 31, 2017. In September 2018, measurement period adjustments to the provisional tax impacts due to the filing of our 2017 income tax returns resulted in a reduction in our income tax expense of $12 million. The reduction consisted of a net income tax benefit of $7 million for the remeasurement of our deferred income tax assets and liabilities due to the decrease in the federal corporate income tax rate and an income tax benefit of $5 million for the one-time, mandatory transition tax. Additional adjustments may be necessary in future periods due to, among other things, the significant complexity of the Act and anticipated additional regulatory guidance that may be issued by the Internal Revenue Service (“IRS”), changes in analysis, interpretations and assumptions the Company has made and actions the Company may take as a result of the Act. We are continuing to gather information to assess the application of the Act and expect to complete our analysis during 2018. Adjustments to Accruals and Related Deferred Taxes — During the three and nine months ended September 30, 2018, adjustments to our accruals and related deferred taxes due to the filing of our 2017 income tax returns and changes in state laws resulted in a reduction in our income tax expense of $27 million and $35 million, respectively, compared with $15 million for both of the prior year periods. Investments Qualifying for Federal Tax Credits — We have significant financial interests in entities established to invest in and manage low-income housing properties and a refined coal facility. On September 28, 2018 we acquired an additional noncontrolling interest in a limited liability company established to invest in and manage low-income housing properties. Our consideration for this investment totaled $157 million, which was comprised of a $139 million note payable and an initial cash payment of $18 million. We support the operations of these entities in exchange for a pro-rata share of the tax credits they generate. The low-income housing investments and the coal facility’s refinement processes qualify for federal tax credits that we expect to realize through 2030 under Sections 42 and 45D, and through 2019 under Section 45, respectively, of the Internal Revenue Code. We account for our investments in these entities using the equity method of accounting, recognizing our share of each entity’s results of operations and other reductions in the value of our investments in equity in net losses of unconsolidated entities, in our Condensed Consolidated Statements of Operations. During the three and nine months ended September 30, 2018, we recognized $5 million and $17 million of net losses and a reduction in our income tax expense of $18 million and $40 million, respectively, primarily because of tax credits realized from these investments. During the three and nine months ended September 30, 2017, we recognized $6 million and $21 million of net losses and a reduction in our income tax expense of $14 million and $39 million, respectively, primarily because of tax credits realized from these investments. Interest expense associated with our investments in low-income housing properties was not material for the periods presented. See Note 14 for additional information related to these unconsolidated variable interest entities. Tax Audit Settlements — We are currently under audit by the IRS, the Canada Revenue Agency and various state and local taxing authorities and our audits are in various stages of completion. During the three and nine months ended September 30, 2018, we settled various tax audits, which resulted in a reduction in our income tax expense of $2 million and $35 million, respectively.

Earnings Per Share

9 Months Ended

Sep. 30, 2018

Earnings Per Share

Earnings Per Share

6. Earnings Per Share

Basic and diluted earnings per share were computed using the following common share data (shares in millions):


	Three Months Ended		Nine Months Ended
	September 30,		September 30,
	2018	2017	2018	2017
Number of common shares outstanding at end of period	427.1	434.2	427.1	434.2
Effect of using weighted average common shares outstanding	0.8	3.6	3.2	6.1
Weighted average basic common shares outstanding	427.9	437.8	430.3	440.3
Dilutive effect of equity-based compensation awards and other contingently issuable shares	2.9	3.0	2.9	3.0
Weighted average diluted common shares outstanding	430.8	440.8	433.2	443.3
Potentially issuable shares	7.6	8.2	7.6	8.2
Number of anti-dilutive potentially issuable shares excluded from diluted common shares outstanding	1.5	1.9	1.5	2.3

Commitments and Contingencies	9 Months Ended
Commitments and Contingencies	Sep. 30, 2018
Commitments and Contingencies.
Commitments and Contingencies	7. Commitments and Contingencies Financial Instruments — We have obtained letters of credit, surety bonds and insurance policies and have established trust funds and issued financial guarantees to support tax-exempt bonds, contracts, performance of landfill final capping, closure and post-closure requirements, environmental remediation and other obligations. Letters of credit generally are supported by our $2.75 billion revolving credit facility and other credit facilities established for that purpose. These facilities are discussed further in Note 3. Surety bonds and insurance policies are supported by (i) a diverse group of third-party surety and insurance companies; (ii) an entity in which we have a noncontrolling financial interest or (iii) a wholly-owned insurance captive, the sole business of which is to issue surety bonds and/or insurance policies on our behalf. Management does not expect that any claims against or draws on these instruments would have a material adverse effect on our financial condition, results of operations or cash flows. We have not experienced any unmanageable difficulty in obtaining the required financial assurance instruments for our current operations. In an ongoing effort to mitigate risks of future cost increases and reductions in available capacity, we continue to evaluate various options to access cost-effective sources of financial assurance. Insurance — We carry insurance coverage for protection of our assets and operations from certain risks including general liability, automobile liability, workers’ compensation, real and personal property, directors’ and officers’ liability, pollution legal liability and other coverages we believe are customary to the industry. Our exposure to loss for insurance claims is generally limited to the per incident deductible under the related insurance policy. Our exposure could increase if our insurers are unable to meet their commitments on a timely basis. We have retained a significant portion of the risks related to our general liability, automobile liability and workers’ compensation claims programs. “General liability” refers to the self-insured portion of specific third-party claims made against us that may be covered under our commercial General Liability Insurance Policy. For our self-insured portions, the exposure for unpaid claims and associated expenses, including incurred but not reported losses, is based on an actuarial valuation or internal estimates. The accruals for these liabilities could be revised if future occurrences or loss development significantly differ from such valuations and estimates. In December 2017, we elected to use a wholly-owned insurance captive to insure the deductibles for our general liability, automobile liability and workers’ compensation claims programs. We do not expect the impact of any known casualty, property, environmental or other contingency to have a material impact on our financial condition, results of operations or cash flows. Guarantees — In the ordinary course of our business, WM and WM Holdings enter into guarantee agreements associated with their subsidiaries’ operations. Additionally, WM and WM Holdings have each guaranteed all of the senior debt of the other entity. No additional liabilities have been recorded for these intercompany guarantees because all of the underlying obligations are reflected in our Condensed Consolidated Balance Sheets. See Note 15 for further discussion. As of September 30, 2018, we have guaranteed the obligations and certain performance requirements of third parties in connection with both consolidated and unconsolidated entities, including (i) guarantees to cover certain market value losses for approximately 775 homeowners’ properties adjacent to or near 18 of our landfills and (ii) guarantees totaling $85 million for performance obligations of our Wheelabrator business, divested in 2014. We have also agreed to indemnify certain third-party purchasers against liabilities associated with divested operations prior to such sale. Additionally, under certain of our acquisition agreements, we have provided for additional consideration to be paid to the sellers if established financial targets or other market conditions are achieved post-closing, and we have recognized liabilities for these contingent obligations based on an estimate of the fair value of these contingencies at the time of acquisition. We do not believe that these contingent obligations will have a material adverse effect on the Company’s financial condition, results of operations or cash flows, and we do not expect the financial impact of operational and financial performance guarantees to materially exceed the recorded fair value. Environmental Matters — A significant portion of our operating costs and capital expenditures could be characterized as costs of environmental protection. The nature of our operations, particularly with respect to the construction, operation and maintenance of our landfills, subjects us to an array of laws and regulations relating to the protection of the environment. Under current laws and regulations, we may have liabilities for environmental damage caused by our operations, or for damage caused by conditions that existed before we acquired a site. In addition to remediation activity required by state or local authorities, such liabilities include potentially responsible party (“PRP”) investigations. The costs associated with these liabilities can include settlements, certain legal and consultant fees, as well as incremental internal and external costs directly associated with site investigation and clean-up. Estimating our degree of responsibility for remediation is inherently difficult. We recognize and accrue for an estimated remediation liability when we determine that such liability is both probable and reasonably estimable. Determining the method and ultimate cost of remediation requires that a number of assumptions be made. There can sometimes be a range of reasonable estimates of the costs associated with the likely site remediation alternatives identified in the environmental impact investigation. In these cases, we use the amount within the range that is our best estimate. If no amount within a range appears to be a better estimate than any other, we use the amount that is the low end of such range. If we used the high ends of such ranges, our aggregate potential liability would be approximately $140 million higher than the $237 million recorded in the Condensed Consolidated Balance Sheet as of September 30, 2018. Our ultimate responsibility may differ materially from current estimates. It is possible that technological, regulatory or enforcement developments, the results of environmental studies, the inability to identify other PRPs, the inability of other PRPs to contribute to the settlements of such liabilities, or other factors could require us to record additional liabilities. Our ongoing review of our remediation liabilities, in light of relevant internal and external facts and circumstances, could result in revisions to our accruals that could cause upward or downward adjustments to our balance sheet and income from operations. These adjustments could be material in any given period. As of September 30, 2018, we have been notified by the government that we are a PRP in connection with 75 locations listed on the Environmental Protection Agency’s (“EPA’s”) Superfund National Priorities List (“NPL”). Of the 75 sites at which claims have been made against us, 15 are sites we own. Each of the NPL sites we own was initially developed by others as a landfill disposal facility. At each of these facilities, we are working in conjunction with the government to evaluate or remediate identified site problems, and we have either agreed with other legally liable parties on an arrangement for sharing the costs of remediation or are working toward a cost-sharing agreement. We generally expect to receive any amounts due from other participating parties at or near the time that we make the remedial expenditures. The other 60 NPL sites, which we do not own, are at various procedural stages under the Comprehensive Environmental Response, Compensation and Liability Act of 1980, as amended, known as CERCLA or Superfund. The majority of proceedings involving NPL sites that we do not own are based on allegations that certain of our subsidiaries (or their predecessors) transported hazardous substances to the sites, often prior to our acquisition of these subsidiaries. CERCLA generally provides for liability for those parties owning, operating, transporting to or disposing at the sites. Proceedings arising under Superfund typically involve numerous waste generators and other waste transportation and disposal companies and seek to allocate or recover costs associated with site investigation and remediation, which costs could be substantial and could have a material adverse effect on our consolidated financial statements. At some of the sites at which we have been identified as a PRP, our liability is well defined as a consequence of a governmental decision and an agreement among liable parties as to the share each will pay for implementing that remedy. At other sites, where no remedy has been selected or the liable parties have been unable to agree on an appropriate allocation, our future costs are uncertain. On October 11, 2017, the EPA issued its Record of Decision (“ROD”) with respect to the previously proposed remediation plan for the San Jacinto waste pits in Harris County, Texas. McGinnes Industrial Maintenance Corporation (“MIMC”), an indirect wholly-owned subsidiary of WM, operated some of the waste pits from 1965 to 1966 and has been named as a site PRP. In 1998, WM acquired the stock of the parent entity of MIMC. MIMC has been working with the EPA and other named PRPs as the process of addressing the site proceeds. On April 9, 2018, MIMC and International Paper Company entered into an Administrative Order on Consent agreement with the EPA to develop a remedial design for the EPA’s selected remedy for the site. Allocation of responsibility among the PRPs for the selected remedy has not been established. As of September 30, 2018 and December 31, 2017, the recorded liability for MIMC’s estimated potential share of the EPA’s selected remedy and related costs was $55 million. MIMC’s ultimate liability could be materially different from current estimates. Item 103 of the SEC’s Regulation S-K requires disclosure of certain environmental matters when a governmental authority is a party to the proceedings, or such proceedings are known to be contemplated, unless we reasonably believe that the matter will result in no monetary sanctions, or in monetary sanctions, exclusive of interest and costs, of less than $100,000. The following matters are disclosed in accordance with that requirement. We do not currently believe that the eventual outcome of any such matters, individually or in the aggregate, could have a material adverse effect on the Company’s business, financial condition, results of operations or cash flows. On July 10, 2013, the EPA issued a Notice of Violation ("NOV") to Waste Management of Wisconsin, Inc., an indirect wholly-owned subsidiary of WM, alleging violations of the Resource Conservation Recovery Act concerning acceptance of certain waste that was not permitted to be disposed of at the Metro Recycling & Disposal Facility in Franklin, Wisconsin. The parties are exchanging information and working to resolve the NOV. The Hawaii Department of Health and the EPA have asserted civil penalty claims against Waste Management of Hawaii, Inc. (“WMHI”), an indirect wholly-owned subsidiary of WM, based on stormwater discharges at the Waimanalo Gulch Sanitary Landfill following two major rainstorms in December 2010 and January 2011 and alleged violations of stormwater permit requirements prior to and after the storms. WMHI operates the landfill for the City and County of Honolulu. From time to time, we are also named as defendants in personal injury and property damage lawsuits, including purported class actions, on the basis of having owned, operated or transported waste to a disposal facility that is alleged to have contaminated the environment or, in certain cases, on the basis of having conducted environmental remediation activities at sites. Some of the lawsuits may seek to have us pay the costs of monitoring of allegedly affected sites and health care examinations of allegedly affected persons for a substantial period of time even where no actual damage is proven. While we believe we have meritorious defenses to these lawsuits, the ultimate resolution is often substantially uncertain due to the difficulty of determining the cause, extent and impact of alleged contamination (which may have occurred over a long period of time), the potential for successive groups of complainants to emerge, the diversity of the individual plaintiffs’ circumstances, and the potential contribution or indemnification obligations of co-defendants or other third parties, among other factors. Additionally, we often enter into agreements with landowners imposing obligations on us to meet certain regulatory or contractual conditions upon site closure or upon termination of the agreements. Compliance with these agreements inherently involves subjective determinations and may result in disputes, including litigation. Litigation — As a large company with operations across the U.S. and Canada, we are subject to various proceedings, lawsuits, disputes and claims arising in the ordinary course of our business. Many of these actions raise complex factual and legal issues and are subject to uncertainties. Actions that have been filed against us, and that may be filed against us in the future, include personal injury, property damage, commercial, customer, and employment-related claims, including purported state and national class action lawsuits related to: alleged environmental contamination, including releases of hazardous material and odors; sales and marketing practices, customer service agreements and prices and fees; and federal and state wage and hour and other laws. The plaintiffs in some actions seek unspecified damages or injunctive relief, or both. These actions are in various procedural stages, and some are covered, in part, by insurance. We currently do not believe that the eventual outcome of any such actions will have a material adverse effect on the Company’s business, financial condition, results of operations or cash flows. WM’s charter and bylaws provide that WM shall indemnify against all liabilities and expenses, and upon request shall advance expenses to any person, who is subject to a pending or threatened proceeding because such person is or was a director or officer of the Company. Such indemnification is required to the maximum extent permitted under Delaware law. Accordingly, the director or officer must execute an undertaking to reimburse the Company for any fees advanced if it is later determined that the director or officer was not permitted to have such fees advanced under Delaware law. Additionally, the Company has direct contractual obligations to provide indemnification to each of the members of WM’s Board of Directors and each of WM’s executive officers. The Company may incur substantial expenses in connection with the fulfillment of its advancement of costs and indemnification obligations in connection with actions or proceedings that may be brought against its former or current officers, directors and employees. Multiemployer Defined Benefit Pension Plans — About 20% of our workforce is covered by collective bargaining agreements with various local unions across the U.S. and Canada. As a result of some of these agreements, certain of our subsidiaries are participating employers in a number of trustee-managed multiemployer defined benefit pension plans (“Multiemployer Pension Plans”) for the covered employees. In connection with our ongoing renegotiation of various collective bargaining agreements, we may discuss and negotiate for the complete or partial withdrawal from one or more of these Multiemployer Pension Plans. A complete or partial withdrawal from a Multiemployer Pension Plan may also occur if employees covered by a collective bargaining agreement vote to decertify a union from continuing to represent them. Any other circumstance resulting in a decline in Company contributions to a Multiemployer Pension Plan through a reduction in the labor force, whether through attrition over time or through a business event (such as the discontinuation or nonrenewal of a customer contract, the decertification of a union, or relocation, reduction or discontinuance of certain operations) may also trigger a complete or partial withdrawal from one or more of these pension plans. We do not believe that any future liability relating to our past or current participation in, or withdrawals from, the Multiemployer Pension Plans to which we contribute will have a material adverse effect on our business, financial condition or liquidity. However, liability for future withdrawals could have a material adverse effect on our results of operations or cash flows for a particular reporting period, depending on the number of employees withdrawn and the financial condition of the Multiemployer Pension Plan(s) at the time of such withdrawal(s). Tax Matters — We participate in the IRS’s Compliance Assurance Process, which means we work with the IRS throughout the year towards resolving any material issues prior to the filing of our annual tax return. Any unresolved issues as of the tax return filing date are subject to routine examination procedures. We are currently in the examination phase of IRS audits for the 2017 and 2018 tax years and expect these audits to be completed within the next 18 months. We are also currently undergoing audits by various state and local jurisdictions for tax years that date back to 2011. Additionally, we are under audit by the Canada Revenue Agency for the 2014 tax year. We maintain a liability for uncertain tax positions, the balance of which management believes is adequate. Results of audit assessments by taxing authorities are not currently expected to have a material adverse effect on our financial condition, results of operations or cash flows.

Segment and Related Information

9 Months Ended

Sep. 30, 2018

Segment and Related Information

Segment and Related Information

8. Segment and Related Information

We evaluate, oversee and manage the financial performance of our Solid Waste business subsidiaries through our 17 Areas. The 17 Areas constitute our operating segments and we have evaluated the aggregation criteria and concluded that, based on the similarities between our Areas, including the fact that our Solid Waste business is homogenous across geographies with the same services offered across the Areas, aggregation of our Areas is appropriate for purposes of presenting our reportable segments. Accordingly, we have aggregated our 17 Areas into three tiers that we believe have similar economic characteristics and future prospects based in large part on a review of the Areas’ income from operations margins. The economic variations experienced by our Areas are attributable to a variety of factors, including regulatory environment of the Area; economic environment of the Area, including level of commercial and industrial activity; population density; service offering mix and disposal logistics, with no one factor being singularly determinative of an Area’s current or future economic performance.

Annually, we analyze the Areas’ income from operations margins for purposes of segment reporting and in the fourth quarter of 2017, we realigned our Solid Waste tiers to reflect changes in their relative economic characteristics and prospects. These changes are the results of various factors including acquisitions, divestments, business mix and the economic climate of various geographies. Reclassifications have been made to our prior period consolidated financial information to conform to the most current presentation.

Tier 1 is comprised of our operations across the Southern U.S., with the exception of Southern California and the Florida peninsula, and also includes the New England states, the tri-state area of Michigan, Indiana and Ohio, and Western Canada. Tier 2 now includes Southern California, Eastern Canada, Wisconsin and Minnesota. Tier 3 now encompasses all the remaining operations including the Pacific Northwest and Northern California, the Mid-Atlantic region of the U.S., the Florida peninsula, Illinois and Missouri.

The operating segments not evaluated and overseen through the 17 Areas are presented herein as “Other” as these operating segments do not meet the criteria to be aggregated with other operating segments and do not meet the quantitative criteria to be separately reported.

Summarized financial information concerning our reportable segments is shown in the following table (in millions):


	Gross		Intercompany		Net		Income
	Operating		Operating		Operating		from
	Revenues		Revenues		Revenues		Operations
Three Months Ended September 30:
2018
Solid Waste:
Tier 1	$	1,506	$	(277)	$	1,229	$	416
Tier 2		671		(127)		544		142
Tier 3		1,818		(353)		1,465		291
Solid Waste		3,995		(757)		3,238		849
Other		629		(45)		584		(15)
		4,624		(802)		3,822		834
Corporate and Other		—		—		—		(135)
Total	$	4,624	$	(802)	$	3,822	$	699

2017
Solid Waste:
Tier 1	$	1,432	$	(258)	$	1,174	$	398
Tier 2		660		(114)		546		142
Tier 3		1,711		(313)		1,398		313
Solid Waste		3,803		(685)		3,118		853
Other		662		(64)		598		(16)
		4,465		(749)		3,716		837
Corporate and Other		—		—		—		(136)
Total	$	4,465	$	(749)	$	3,716	$	701


	Gross		Intercompany		Net		Income
	Operating		Operating		Operating		from
	Revenues		Revenues		Revenues		Operations
Nine Months Ended September 30:
2018
Solid Waste:
Tier 1	$	4,364	$	(787)	$	3,577	$	1,176
Tier 2		1,947		(361)		1,586		405
Tier 3		5,227		(1,012)		4,215		877
Solid Waste		11,538		(2,160)		9,378		2,458
Other		1,849		(155)		1,694		(25)
		13,387		(2,315)		11,072		2,433
Corporate and Other		—		—		—		(411)
Total	$	13,387	$	(2,315)	$	11,072	$	2,022

2017
Solid Waste:
Tier 1	$	4,189	$	(754)	$	3,435	$	1,159
Tier 2		1,903		(329)		1,574		400
Tier 3		4,979		(909)		4,070		877
Solid Waste		11,071		(1,992)		9,079		2,436
Other		1,922		(168)		1,754		(66)
		12,993		(2,160)		10,833		2,370
Corporate and Other		—		—		—		(438)
Total	$	12,993	$	(2,160)	$	10,833	$	1,932

The mix of operating revenues from our major lines of business are as follows (in millions):


	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2018		2017		2018		2017
Commercial	$	1,007	$	936	$	2,948	$	2,764
Residential		639		635		1,885		1,888
Industrial		723		673		2,068		1,930
Other		117		107		333		330
Total collection		2,486		2,351		7,234		6,912
Landfill		926		884		2,646		2,487
Transfer		445		412		1,257		1,192
Recycling		337		375		954		1,122
Other (a)		430		443		1,296		1,280
Intercompany (b)		(802)		(749)		(2,315)		(2,160)
Total	$	3,822	$	3,716	$	11,072	$	10,833

(a)

The “Other” line of business includes (i) our WMSBS organization; (ii) our landfill gas-to-energy operations; (iii) certain services within our EES organization, including our construction and remediation services and our services associated with the disposal of fly ash and (iv) certain other expanded service offerings and solutions. In addition, our “Other” line of business reflects the results of non-operating entities that provide financial assurance and self-insurance support, net of intercompany activity.

(b)

Intercompany revenues between lines of business are eliminated in the Condensed Consolidated Financial Statements included within this report.

Fluctuations in our operating results may be caused by many factors, including period-to-period changes in the relative contribution of revenue by each line of business, changes in commodity prices and general economic conditions. In addition, our revenues and income from operations typically reflect seasonal patterns. Our operating revenues tend to be somewhat higher in summer months, primarily due to the higher construction and demolition waste volumes. The volumes of industrial and residential waste in certain regions where we operate also tend to increase during the summer months. Our second and third quarter revenues and results of operations typically reflect these seasonal trends.

Service disruptions caused by severe storms, extended periods of inclement weather or climate extremes resulting from climate change can significantly affect the operating results of the Areas affected. On the other hand, certain destructive weather conditions that tend to occur during the second half of the year, such as the hurricanes that most often impact our operations in the Southern and Eastern U.S., can increase our revenues in the Areas affected. While weather-related and other event driven special projects can boost revenues through additional work for a limited time, as a result of significant start-up costs and other factors, such revenue can generate earnings at comparatively lower margins.

Acquisitions and Divestitures	9 Months Ended
Acquisitions and Divestitures	Sep. 30, 2018
Acquisitions and Divestitures
Acquisitions and Divestitures	9. Acquisitions and Divestitures Acquisitions During the nine months ended September 30, 2018, we acquired 21 solid waste businesses. Total consideration, net of cash acquired, for these acquisitions was $350 million, which included $329 million in cash paid and $21 million of other consideration, primarily purchase price holdbacks. During the nine months ended September 30, 2018, we also paid $13 million of purchase price holdbacks, of which $7 million related to current year acquisitions. The businesses acquired provide collection, transfer and disposal services. As of September 30, 2018, the allocation of the purchase price for these acquisitions is preliminary; fair value estimates of identifiable assets acquired and liabilities assumed are based on management’s estimates, judgments and assumptions and are subject to change until finalized. Divestitures During the nine months ended September 30, 2018, we sold certain ancillary operations and received cash proceeds from these divestitures of $86 million and recognized net gains of $43 million, which are included in (gain) loss from divestitures, asset impairments and unusual items, net in the Condensed Consolidated Statement of Operations.

Asset Impairments and Unusual Items	9 Months Ended
Asset Impairments and Unusual Items	Sep. 30, 2018
Asset Impairments and Unusual Items
Asset Impairments and Unusual Items	10. Asset Impairments and Unusual Items (Gain) loss from divestitures, asset impairments and unusual items, net During the nine months ended September 30, 2018, we recognized a net gain of $14 million, primarily related to net gains from divestitures of $43 million due to the sale of certain ancillary operations, which were partially offset by a $29 million charge to impair a landfill in our Tier 3 segment based on an internally developed discounted projected cash flow analysis, taking into account continued volume decreases and revised capping cost estimates. Equity in net losses of unconsolidated entities During the nine months ended September 30, 2017, we recognized $28 million of impairment charges to write down equity method investments in waste diversion technology companies to their estimated fair values.

Accumulated Other Comprehensive Income (Loss)

9 Months Ended

Sep. 30, 2018

Accumulated Other Comprehensive Income (Loss)

Accumulated Other Comprehensive Income (Loss)

11. Accumulated Other Comprehensive Income (Loss)

The changes in the balances of each component of accumulated other comprehensive income (loss), net of tax, which is included as a component of Waste Management, Inc. stockholders’ equity, are as follows (in millions, with amounts in parentheses representing decreases to accumulated other comprehensive income):


					Foreign		Post-
			Available-		Currency		Retirement
	Derivative		for-Sale		Translation		Benefit
	Instruments		Securities		Adjustments		Obligations		Total
Balance, December 31, 2017	$	(33)	$	15	$	29	$	(3)	$	8
Other comprehensive income (loss) before reclassifications, net of tax expense (benefit) of $0, $3, $0 and $0, respectively		—		8		(33)		—		(25)
Amounts reclassified from accumulated other comprehensive (income) loss, net of tax (expense) benefit of $2, $0, $0 and $0, respectively		6		—		—		—		6
Net current period other comprehensive income (loss)		6		8		(33)		—		(19)
Adoption of new accounting standard (a)		(7)		3		—		(1)		(5)
Balance, September 30, 2018	$	(34)	$	26	$	(4)	$	(4)	$	(16)

(a)

As of January 1, 2018, we adopted ASU 2018-02 and reclassified stranded tax effects to retained earnings. See Note 1 for further discussion of ASU 2018-02.

We had no active derivatives outstanding during the reported periods. Amounts reclassified out of accumulated other comprehensive income (loss) associated with our previously terminated cash flow hedges were not material for the periods presented.

Common Stock Repurchase Program	9 Months Ended
Common Stock Repurchase Program	Sep. 30, 2018
Common Stock Repurchase Program
Common Stock Repurchase Program	12. Common Stock Repurchase Program The Company repurchases shares of its common stock as part of capital allocation programs authorized by our Board of Directors. During the six months ended June 30, 2018, we entered into and completed two accelerated share repurchase (“ASR”) agreements to repurchase $450 million of our common stock, and we received 5.4 million shares in connection with these two ASR agreements. In July 2018, we entered into a third ASR agreement to repurchase $200 million of our common stock. Pursuant to the July 2018 ASR agreement, we delivered $200 million cash and received 1.8 million shares. The weighted average per share price of the 7.2 million shares of common stock received under the three ASR agreements through September 30, 2018 was $85.04. The July 2018 ASR agreement completed in October 2018, at which time we received 0.4 million additional shares based on a final weighted average per share price of $90.07. From March 2018 through May 2018, we repurchased an additional 1.2 million shares in open market transactions in compliance with Rule 10b5-1 and Rule 10b-18 of the Exchange Act for $100 million, inclusive of per-share commissions, at a weighted average per share price of $83.20. As of September 30, 2018, the Company has authorization for $500 million of future share repurchases. Any future share repurchases pursuant to this authorization of our Board of Directors will be made at the discretion of management and will depend on factors similar to those considered by the Board of Directors in making dividend declarations, including our net earnings, financial condition and cash required for future business plans.

Fair Value Measurements

9 Months Ended

Sep. 30, 2018

Fair Value Measurements

Fair Value Measurements

13. Fair Value Measurements

Assets and Liabilities Accounted for at Fair Value

Our assets and liabilities that are measured at fair value on a recurring basis include the following (in millions):


	September 30,		December 31,
	2018		2017
Fair Value Measurements Using:
Quoted prices in active markets (Level 1):
Money market funds	$	82	$	225
		82		225

Significant other observable inputs (Level 2):
Available-for-sale securities		50		49
Fixed-income securities		45		47
		95		96

Significant unobservable inputs (Level 3):
Redeemable preferred stock (a)		66		55
		66		55

Total Assets	$	243	$	376

(a)

When available, Level 3 investments have been measured based on third-party investors’ recent or pending transactions in these securities, which are considered the best evidence of fair value. When this evidence is not available, we use other valuation techniques as appropriate and available. These valuation methodologies may include transactions in similar instruments, discounted cash flow techniques, third-party appraisals or industry multiples and public company comparable transactions. In September 2018, the fair value of our redeemable preferred stock increased $11 million based on a recent third-party investors’ transaction in these securities.

Fair Value of Debt

As of September 30, 2018 and December 31, 2017, the carrying value of our debt was $10.0 billion and $9.5 billion, respectively. The estimated fair value of our debt was approximately $10.1 billion and $9.9 billion as of September 30, 2018 and December 31, 2017.

Although we have determined the estimated fair value amounts using available market information and commonly accepted valuation methodologies, considerable judgment is required in interpreting market data to develop the estimates of fair value. Accordingly, our estimates are not necessarily indicative of the amounts that we, or holders of the instruments, could realize in a current market exchange. The use of different assumptions or estimation methodologies could have a material effect on the estimated fair values. The fair value estimates are based on Level 2 inputs of the fair value hierarchy available as of September 30, 2018 and December 31, 2017. These amounts have not been revalued since those dates, and current estimates of fair value could differ significantly from the amounts presented.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Variable Interest Entities	9 Months Ended
Variable Interest Entities	Sep. 30, 2018
Variable Interest Entities
Variable Interest Entities	14. Variable Interest Entities Following is a description of our financial interests in unconsolidated and consolidated variable interest entities that we consider significant: Low-Income Housing Properties and Refined Coal Facility Investments We do not consolidate our investments in entities established to manage low-income housing properties and a refined coal facility because we are not the primary beneficiary of these entities as we do not have the power to individually direct the activities of these entities. Accordingly, we account for these investments under the equity method of accounting. Our aggregate investment balance in these entities was $199 million and $59 million as of September 30, 2018 and December 31, 2017, respectively. The debt balance related to our investments in low-income housing properties was $156 million and $34 million as of September 30, 2018 and December 31, 2017, respectively. Additional information related to these investments is discussed in Note 5. Trust Funds for Final Capping, Closure, Post-Closure or Environmental Remediation Obligations Unconsolidated Variable Interest Entities — Trust funds that are established for both the benefit of the Company and the host community in which we operate are not consolidated because we are not the primary beneficiary of these entities as we either do not have the (i) power to direct the significant activities of the trusts or (ii) power over the trusts’ significant activities is shared. Our interests in these trusts are accounted for as investments in unconsolidated entities and receivables. These amounts are recorded in other receivables, investments in unconsolidated entities and long-term other assets in our Condensed Consolidated Balance Sheets, as appropriate. We also reflect our share of the unrealized gains and losses on available-for-sale securities held by these trusts as a component of our accumulated other comprehensive income (loss). Our investments and receivables related to these trusts had an aggregate carrying value of $99 million as of September 30, 2018 and December 31, 2017. Consolidated Variable Interest Entities — Trust funds for which we are the sole beneficiary are consolidated because we are the primary beneficiary. These trust funds are recorded in restricted trust and escrow accounts in our Condensed Consolidated Balance Sheets. Unrealized gains and losses on available-for-sale securities held by these trusts are recorded as a component of our accumulated other comprehensive income (loss). These trusts had a fair value of $103 million and $101 million as of September 30, 2018 and December 31, 2017, respectively.

Condensed Consolidating Financial Statements

9 Months Ended

Sep. 30, 2018

Condensed Consolidating Financial Statements

Condensed Consolidating Financial Statements

15. Condensed Consolidating Financial Statements

WM Holdings has fully and unconditionally guaranteed all of WM’s senior indebtedness. WM has fully and unconditionally guaranteed all of WM Holdings’ senior indebtedness. None of WM’s other subsidiaries have guaranteed any of WM’s or WM Holdings’ debt. As a result of these guarantee arrangements, we are required to present the following condensed consolidating financial information (in millions):

CONDENSED CONSOLIDATING BALANCE SHEETS

September 30, 2018

(Unaudited)


			WM		Non-Guarantor
	WM		Holdings		Subsidiaries		Eliminations		Consolidated
ASSETS
Current assets:
Cash and cash equivalents	$	—	$	—	$	83	$	—	$	83
Other current assets		46		5		2,541		—		2,592
		46		5		2,624		—		2,675
Property and equipment, net		—		—		11,815		—		11,815
Investments in affiliates		24,055		24,544		—		(48,599)		—
Advances to affiliates		—		—		16,289		(16,289)		—
Other assets		7		31		8,063		—		8,101
Total assets	$	24,108	$	24,580	$	38,791	$	(64,888)	$	22,591

LIABILITIES AND EQUITY
Current liabilities:
Current portion of long-term debt	$	104	$	—	$	343	$	—	$	447
Accounts payable and other current liabilities		71		4		2,548		—		2,623
		175		4		2,891		—		3,070
Long-term debt, less current portion		7,409		304		1,856		—		9,569
Due to affiliates		16,353		219		6,073		(22,645)		—
Other liabilities		5		—		3,706		—		3,711
Total liabilities		23,942		527		14,526		(22,645)		16,350
Equity:
Stockholders’ equity		6,239		24,053		24,546		(48,599)		6,239
Advances to affiliates		(6,073)		—		(283)		6,356		—
Noncontrolling interests		—		—		2		—		2
		166		24,053		24,265		(42,243)		6,241
Total liabilities and equity	$	24,108	$	24,580	$	38,791	$	(64,888)	$	22,591

CONDENSED CONSOLIDATING BALANCE SHEETS (Continued)

December 31, 2017


			WM		Non-Guarantor
	WM		Holdings		Subsidiaries		Eliminations		Consolidated
ASSETS
Current assets:
Cash and cash equivalents	$	—	$	—	$	22	$	—	$	22
Other current assets		5		5		2,592		—		2,602
		5		5		2,614		—		2,624
Property and equipment, net		—		—		11,559		—		11,559
Investments in affiliates		22,393		22,893		—		(45,286)		—
Advances to affiliates		—		—		15,349		(15,349)		—
Other assets		9		31		7,606		—		7,646
Total assets	$	22,407	$	22,929	$	37,128	$	(60,635)	$	21,829

LIABILITIES AND EQUITY
Current liabilities:
Current portion of long-term debt	$	537	$	—	$	202	$	—	$	739
Accounts payable and other current liabilities		55		9		2,459		—		2,523
		592		9		2,661		—		3,262
Long-term debt, less current portion		6,457		304		1,991		—		8,752
Due to affiliates		15,404		224		6,073		(21,701)		—
Other liabilities		8		—		3,765		—		3,773
Total liabilities		22,461		537		14,490		(21,701)		15,787
Equity:
Stockholders’ equity		6,019		22,392		22,894		(45,286)		6,019
Advances to affiliates		(6,073)		—		(279)		6,352		—
Noncontrolling interests		—		—		23		—		23
		(54)		22,392		22,638		(38,934)		6,042
Total liabilities and equity	$	22,407	$	22,929	$	37,128	$	(60,635)	$	21,829

CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS

Three Months Ended September 30, 2018

(Unaudited)


			WM		Non-Guarantor
	WM		Holdings		Subsidiaries		Eliminations		Consolidated
Operating revenues	$	—	$	—	$	3,866	$	(44)	$	3,822
Costs and expenses		44		—		3,123		(44)		3,123
Income from operations		(44)		—		743		—		699
Other income (expense):
Interest expense, net		(78)		(6)		(9)		—		(93)
Equity in earnings of subsidiaries, net of tax		589		592		—		(1,181)		—
Other, net		—		—		(9)		—		(9)
		511		586		(18)		(1,181)		(102)
Income before income taxes		467		586		725		(1,181)		597
Income tax expense (benefit)		(32)		(2)		133		—		99
Consolidated net income		499		588		592		(1,181)		498
Less: Net income (loss) attributable to noncontrolling interests		—		—		(1)		—		(1)
Net income attributable to Waste Management, Inc.	$	499	$	588	$	593	$	(1,181)	$	499

Three Months Ended September 30, 2017

(Unaudited)


			WM		Non-Guarantor
	WM		Holdings		Subsidiaries		Eliminations		Consolidated
Operating revenues	$	—	$	—	$	3,716	$	—	$	3,716
Costs and expenses		—		—		3,015		—		3,015
Income from operations		—		—		701		—		701
Other income (expense):
Interest expense, net		(75)		(5)		(10)		—		(90)
Equity in earnings of subsidiaries, net of tax		432		435		—		(867)		—
Other, net		—		—		(8)		—		(8)
		357		430		(18)		(867)		(98)
Income before income taxes		357		430		683		(867)		603
Income tax expense (benefit)		(29)		(2)		246		—		215
Consolidated net income		386		432		437		(867)		388
Less: Net income (loss) attributable to noncontrolling interests		—		—		2		—		2
Net income attributable to Waste Management, Inc.	$	386	$	432	$	435	$	(867)	$	386

CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS (Continued)

Nine Months Ended September 30, 2018

(Unaudited)


			WM		Non‑Guarantor
	WM		Holdings		Subsidiaries		Eliminations		Consolidated
Operating revenues	$	—	$	—	$	11,204	$	(132)	$	11,072
Costs and expenses		132		—		9,050		(132)		9,050
Income from operations		(132)		—		2,154		—		2,022
Other income (expense):
Interest expense, net		(232)		(15)		(30)		—		(277)
Equity in earnings of subsidiaries, net of tax		1,662		1,672		—		(3,334)		—
Other, net		—		—		(28)		—		(28)
		1,430		1,657		(58)		(3,334)		(305)
Income before income taxes		1,298		1,657		2,096		(3,334)		1,717
Income tax expense (benefit)		(96)		(4)		425		—		325
Consolidated net income		1,394		1,661		1,671		(3,334)		1,392
Less: Net income (loss) attributable to noncontrolling interests		—		—		(2)		—		(2)
Net income attributable to Waste Management, Inc.	$	1,394	$	1,661	$	1,673	$	(3,334)	$	1,394

Nine Months Ended September 30, 2017

(Unaudited)


			WM		Non‑Guarantor
	WM		Holdings		Subsidiaries		Eliminations		Consolidated
Operating revenues	$	—	$	—	$	10,833	$	—	$	10,833
Costs and expenses		—		—		8,901		—		8,901
Income from operations		—		—		1,932		—		1,932
Other income (expense):
Interest expense, net		(223)		(15)		(34)		—		(272)
Equity in earnings of subsidiaries, net of tax		1,181		1,190		—		(2,371)		—
Other, net		—		—		(53)		—		(53)
		958		1,175		(87)		(2,371)		(325)
Income before income taxes		958		1,175		1,845		(2,371)		1,607
Income tax expense (benefit)		(88)		(6)		655		—		561
Consolidated net income		1,046		1,181		1,190		(2,371)		1,046
Less: Net income (loss) attributable to noncontrolling interests		—		—		—		—		—
Net income attributable to Waste Management, Inc.	$	1,046	$	1,181	$	1,190	$	(2,371)	$	1,046

CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME

(Unaudited)


			WM		Non-Guarantor
	WM		Holdings		Subsidiaries		Eliminations		Consolidated
Three Months Ended September 30:
2018
Comprehensive income	$	501	$	588	$	623	$	(1,181)	$	531
Less: Comprehensive income (loss) attributable to noncontrolling interests		—		—		(1)		—		(1)
Comprehensive income attributable to Waste Management, Inc.	$	501	$	588	$	624	$	(1,181)	$	532

2017
Comprehensive income	$	388	$	432	$	482	$	(867)	$	435
Less: Comprehensive income (loss) attributable to noncontrolling interests		—		—		2		—		2
Comprehensive income attributable to Waste Management, Inc.	$	388	$	432	$	480	$	(867)	$	433


			WM		Non-Guarantor
	WM		Holdings		Subsidiaries		Eliminations		Consolidated
Nine Months Ended September 30:
2018
Comprehensive income	$	1,400	$	1,661	$	1,646	$	(3,334)	$	1,373
Less: Comprehensive income (loss) attributable to noncontrolling interests		—		—		(2)		—		(2)
Comprehensive income attributable to Waste Management, Inc.	$	1,400	$	1,661	$	1,648	$	(3,334)	$	1,375

2017
Comprehensive income	$	1,052	$	1,181	$	1,278	$	(2,371)	$	1,140
Less: Comprehensive income (loss) attributable to noncontrolling interests		—		—		—		—		—
Comprehensive income attributable to Waste Management, Inc.	$	1,052	$	1,181	$	1,278	$	(2,371)	$	1,140

CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS

Nine Months Ended September 30, 2018

(Unaudited)


			WM		Non-Guarantor
	WM(a)		Holdings(a)		Subsidiaries(a)		Eliminations		Consolidated
Cash flows provided by (used in):
Operating activities	$	—	$	—	$	2,658	$	—	$	2,658
Investing activities		—		—		(1,506)		—		(1,506)
Financing activities		—		—		(1,015)		—		(1,015)
Effect of exchange rate changes on cash, cash equivalents and restricted cash and cash equivalents		—		—		—		—		—
Intercompany activity		—		—		—		—		—
Increase in cash, cash equivalents and restricted cash and cash equivalents		—		—		137		—		137
Cash, cash equivalents and restricted cash and cash equivalents at beginning of period		—		—		293		—		293
Cash, cash equivalents and restricted cash and cash equivalents at end of period	$	—	$	—	$	430	$	—	$	430

Nine Months Ended September 30, 2017

(Unaudited)


			WM		Non-Guarantor
	WM(a)		Holdings(a)		Subsidiaries(a)		Eliminations		Consolidated
Cash flows provided by (used in):
Operating activities	$	—	$	—	$	2,388	$	—	$	2,388
Investing activities		—		—		(1,050)		—		(1,050)
Financing activities		—		—		(1,331)		—		(1,331)
Effect of exchange rate changes on cash, cash equivalents and restricted cash and cash equivalents		—		—		1		—		1
Intercompany activity		—		—		—		—		—
Increase in cash, cash equivalents and restricted cash and cash equivalents		—		—		8		—		8
Cash, cash equivalents and restricted cash and cash equivalents at beginning of period		—		—		94		—		94
Cash, cash equivalents and restricted cash and cash equivalents at end of period	$	—	$	—	$	102	$	—	$	102

(a)

Cash receipts and payments of WM and WM Holdings are transacted by Non-Guarantor Subsidiaries.

Basis of Presentation (Policies)

9 Months Ended

Sep. 30, 2018

Basis of Presentation

Basis of Presentation

Adoption of New Accounting Standards and New Accounting Standards Pending Adoption

Adoption of New Accounting Standards

New Accounting Standards Pending Adoption

Reclassifications

When necessary, reclassifications have been made to our prior period financial information to conform to the current year presentation.

Landfill and Environmental Remediation Liabilities (Tables)

9 Months Ended

Sep. 30, 2018

Landfill and Environmental Remediation Liabilities

Liabilities for Landfill and Environmental Remediation Costs

Liabilities for landfill and environmental remediation costs are presented in the table below (in millions):


	September 30, 2018						December 31, 2017
			Environmental						Environmental
	Landfill		Remediation		Total		Landfill		Remediation		Total
Current (in accrued liabilities)	$	131	$	27	$	158	$	128	$	28	$	156
Long-term		1,622		210		1,832		1,547		223		1,770
	$	1,753	$	237	$	1,990	$	1,675	$	251	$	1,926

Changes to Landfill and Environmental Remediation Liabilities

The changes to landfill and environmental remediation liabilities for the nine months ended September 30, 2018 are reflected in the table below (in millions):


			Environmental
	Landfill		Remediation
December 31, 2017	$	1,675	$	251
Obligations incurred and capitalized		62		—
Obligations settled		(71)		(18)
Interest accretion		71		4
Revisions in estimates and interest rate assumptions (a) (b)		7		2
Acquisitions, divestitures and other adjustments		9		(2)
September 30, 2018	$	1,753	$	237

(a)

(b)

Debt (Tables)

9 Months Ended

Sep. 30, 2018

Debt

Components of Debt


	September 30,		December 31,
	2018		2017
Revolving credit facility (weighted average interest rate of 2.7% as of September 30, 2018)	$	44	$	—
Commercial paper program (weighted average interest rate of 2.4% as of September 30, 2018 and 1.9% as of December 31, 2017)		1,053		515
Canadian term loan and revolving credit facility (weighted average effective interest rate of 2.5% as of December 31, 2017)		—		113
Senior notes, maturing through 2045, interest rates ranging from 2.4% to 7.75% (weighted average interest rate of 4.3% as of September 30, 2018 and December 31, 2017)		6,222		6,222
Tax-exempt bonds, maturing through 2045, fixed and variable interest rates ranging from 1.35% to 4.3% (weighted average interest rate of 2.2% as of September 30, 2018 and 2.0% as of December 31, 2017)		2,318		2,370
Capital leases and other, maturing through 2040, interest rates up to 12%		431		327
Debt issuance costs, discounts and other		(52)		(56)
		10,016		9,491
Current portion of long-term debt		447		739
	$	9,569	$	8,752

Earnings Per Share (Tables)

9 Months Ended

Sep. 30, 2018

Earnings Per Share

Common Share Data Used for Computing Basic and Diluted Earnings Per Share

Basic and diluted earnings per share were computed using the following common share data (shares in millions):


	Three Months Ended		Nine Months Ended
	September 30,		September 30,
	2018	2017	2018	2017
Number of common shares outstanding at end of period	427.1	434.2	427.1	434.2
Effect of using weighted average common shares outstanding	0.8	3.6	3.2	6.1
Weighted average basic common shares outstanding	427.9	437.8	430.3	440.3
Dilutive effect of equity-based compensation awards and other contingently issuable shares	2.9	3.0	2.9	3.0
Weighted average diluted common shares outstanding	430.8	440.8	433.2	443.3
Potentially issuable shares	7.6	8.2	7.6	8.2
Number of anti-dilutive potentially issuable shares excluded from diluted common shares outstanding	1.5	1.9	1.5	2.3

Segment and Related Information (Tables)

9 Months Ended

Sep. 30, 2018

Segment and Related Information

Reportable Segments

Summarized financial information concerning our reportable segments is shown in the following table (in millions):


	Gross		Intercompany		Net		Income
	Operating		Operating		Operating		from
	Revenues		Revenues		Revenues		Operations
Three Months Ended September 30:
2018
Solid Waste:
Tier 1	$	1,506	$	(277)	$	1,229	$	416
Tier 2		671		(127)		544		142
Tier 3		1,818		(353)		1,465		291
Solid Waste		3,995		(757)		3,238		849
Other		629		(45)		584		(15)
		4,624		(802)		3,822		834
Corporate and Other		—		—		—		(135)
Total	$	4,624	$	(802)	$	3,822	$	699

2017
Solid Waste:
Tier 1	$	1,432	$	(258)	$	1,174	$	398
Tier 2		660		(114)		546		142
Tier 3		1,711		(313)		1,398		313
Solid Waste		3,803		(685)		3,118		853
Other		662		(64)		598		(16)
		4,465		(749)		3,716		837
Corporate and Other		—		—		—		(136)
Total	$	4,465	$	(749)	$	3,716	$	701


	Gross		Intercompany		Net		Income
	Operating		Operating		Operating		from
	Revenues		Revenues		Revenues		Operations
Nine Months Ended September 30:
2018
Solid Waste:
Tier 1	$	4,364	$	(787)	$	3,577	$	1,176
Tier 2		1,947		(361)		1,586		405
Tier 3		5,227		(1,012)		4,215		877
Solid Waste		11,538		(2,160)		9,378		2,458
Other		1,849		(155)		1,694		(25)
		13,387		(2,315)		11,072		2,433
Corporate and Other		—		—		—		(411)
Total	$	13,387	$	(2,315)	$	11,072	$	2,022

2017
Solid Waste:
Tier 1	$	4,189	$	(754)	$	3,435	$	1,159
Tier 2		1,903		(329)		1,574		400
Tier 3		4,979		(909)		4,070		877
Solid Waste		11,071		(1,992)		9,079		2,436
Other		1,922		(168)		1,754		(66)
		12,993		(2,160)		10,833		2,370
Corporate and Other		—		—		—		(438)
Total	$	12,993	$	(2,160)	$	10,833	$	1,932

Summary of operating revenues mix

The mix of operating revenues from our major lines of business are as follows (in millions):


	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2018		2017		2018		2017
Commercial	$	1,007	$	936	$	2,948	$	2,764
Residential		639		635		1,885		1,888
Industrial		723		673		2,068		1,930
Other		117		107		333		330
Total collection		2,486		2,351		7,234		6,912
Landfill		926		884		2,646		2,487
Transfer		445		412		1,257		1,192
Recycling		337		375		954		1,122
Other (a)		430		443		1,296		1,280
Intercompany (b)		(802)		(749)		(2,315)		(2,160)
Total	$	3,822	$	3,716	$	11,072	$	10,833

(a)

(b)

Intercompany revenues between lines of business are eliminated in the Condensed Consolidated Financial Statements included within this report.

Accumulated Other Comprehensive Income (Loss) (Tables)

9 Months Ended

Sep. 30, 2018

Accumulated Other Comprehensive Income (Loss)

Components of Accumulated Other Comprehensive Income (Loss)


					Foreign		Post-
			Available-		Currency		Retirement
	Derivative		for-Sale		Translation		Benefit
	Instruments		Securities		Adjustments		Obligations		Total
Balance, December 31, 2017	$	(33)	$	15	$	29	$	(3)	$	8
Other comprehensive income (loss) before reclassifications, net of tax expense (benefit) of $0, $3, $0 and $0, respectively		—		8		(33)		—		(25)
Amounts reclassified from accumulated other comprehensive (income) loss, net of tax (expense) benefit of $2, $0, $0 and $0, respectively		6		—		—		—		6
Net current period other comprehensive income (loss)		6		8		(33)		—		(19)
Adoption of new accounting standard (a)		(7)		3		—		(1)		(5)
Balance, September 30, 2018	$	(34)	$	26	$	(4)	$	(4)	$	(16)

(a)

As of January 1, 2018, we adopted ASU 2018-02 and reclassified stranded tax effects to retained earnings. See Note 1 for further discussion of ASU 2018-02.

Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2018

Fair Value Measurements

Fair Value of Assets and Liabilities Measured on Recurring Basis

Our assets and liabilities that are measured at fair value on a recurring basis include the following (in millions):


	September 30,		December 31,
	2018		2017
Fair Value Measurements Using:
Quoted prices in active markets (Level 1):
Money market funds	$	82	$	225
		82		225

Significant other observable inputs (Level 2):
Available-for-sale securities		50		49
Fixed-income securities		45		47
		95		96

Significant unobservable inputs (Level 3):
Redeemable preferred stock (a)		66		55
		66		55

Total Assets	$	243	$	376

(a)

Condensed Consolidating Financial Statements (Tables)

9 Months Ended

Sep. 30, 2018

Condensed Consolidating Financial Statements

Condensed Consolidating Balance Sheets

CONDENSED CONSOLIDATING BALANCE SHEETS

September 30, 2018

(Unaudited)


			WM		Non-Guarantor
	WM		Holdings		Subsidiaries		Eliminations		Consolidated
ASSETS
Current assets:
Cash and cash equivalents	$	—	$	—	$	83	$	—	$	83
Other current assets		46		5		2,541		—		2,592
		46		5		2,624		—		2,675
Property and equipment, net		—		—		11,815		—		11,815
Investments in affiliates		24,055		24,544		—		(48,599)		—
Advances to affiliates		—		—		16,289		(16,289)		—
Other assets		7		31		8,063		—		8,101
Total assets	$	24,108	$	24,580	$	38,791	$	(64,888)	$	22,591

LIABILITIES AND EQUITY
Current liabilities:
Current portion of long-term debt	$	104	$	—	$	343	$	—	$	447
Accounts payable and other current liabilities		71		4		2,548		—		2,623
		175		4		2,891		—		3,070
Long-term debt, less current portion		7,409		304		1,856		—		9,569
Due to affiliates		16,353		219		6,073		(22,645)		—
Other liabilities		5		—		3,706		—		3,711
Total liabilities		23,942		527		14,526		(22,645)		16,350
Equity:
Stockholders’ equity		6,239		24,053		24,546		(48,599)		6,239
Advances to affiliates		(6,073)		—		(283)		6,356		—
Noncontrolling interests		—		—		2		—		2
		166		24,053		24,265		(42,243)		6,241
Total liabilities and equity	$	24,108	$	24,580	$	38,791	$	(64,888)	$	22,591

CONDENSED CONSOLIDATING BALANCE SHEETS (Continued)

December 31, 2017


			WM		Non-Guarantor
	WM		Holdings		Subsidiaries		Eliminations		Consolidated
ASSETS
Current assets:
Cash and cash equivalents	$	—	$	—	$	22	$	—	$	22
Other current assets		5		5		2,592		—		2,602
		5		5		2,614		—		2,624
Property and equipment, net		—		—		11,559		—		11,559
Investments in affiliates		22,393		22,893		—		(45,286)		—
Advances to affiliates		—		—		15,349		(15,349)		—
Other assets		9		31		7,606		—		7,646
Total assets	$	22,407	$	22,929	$	37,128	$	(60,635)	$	21,829

LIABILITIES AND EQUITY
Current liabilities:
Current portion of long-term debt	$	537	$	—	$	202	$	—	$	739
Accounts payable and other current liabilities		55		9		2,459		—		2,523
		592		9		2,661		—		3,262
Long-term debt, less current portion		6,457		304		1,991		—		8,752
Due to affiliates		15,404		224		6,073		(21,701)		—
Other liabilities		8		—		3,765		—		3,773
Total liabilities		22,461		537		14,490		(21,701)		15,787
Equity:
Stockholders’ equity		6,019		22,392		22,894		(45,286)		6,019
Advances to affiliates		(6,073)		—		(279)		6,352		—
Noncontrolling interests		—		—		23		—		23
		(54)		22,392		22,638		(38,934)		6,042
Total liabilities and equity	$	22,407	$	22,929	$	37,128	$	(60,635)	$	21,829

Condensed Consolidating Statements of Operations

CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS

Three Months Ended September 30, 2018

(Unaudited)


			WM		Non-Guarantor
	WM		Holdings		Subsidiaries		Eliminations		Consolidated
Operating revenues	$	—	$	—	$	3,866	$	(44)	$	3,822
Costs and expenses		44		—		3,123		(44)		3,123
Income from operations		(44)		—		743		—		699
Other income (expense):
Interest expense, net		(78)		(6)		(9)		—		(93)
Equity in earnings of subsidiaries, net of tax		589		592		—		(1,181)		—
Other, net		—		—		(9)		—		(9)
		511		586		(18)		(1,181)		(102)
Income before income taxes		467		586		725		(1,181)		597
Income tax expense (benefit)		(32)		(2)		133		—		99
Consolidated net income		499		588		592		(1,181)		498
Less: Net income (loss) attributable to noncontrolling interests		—		—		(1)		—		(1)
Net income attributable to Waste Management, Inc.	$	499	$	588	$	593	$	(1,181)	$	499

Three Months Ended September 30, 2017

(Unaudited)


			WM		Non-Guarantor
	WM		Holdings		Subsidiaries		Eliminations		Consolidated
Operating revenues	$	—	$	—	$	3,716	$	—	$	3,716
Costs and expenses		—		—		3,015		—		3,015
Income from operations		—		—		701		—		701
Other income (expense):
Interest expense, net		(75)		(5)		(10)		—		(90)
Equity in earnings of subsidiaries, net of tax		432		435		—		(867)		—
Other, net		—		—		(8)		—		(8)
		357		430		(18)		(867)		(98)
Income before income taxes		357		430		683		(867)		603
Income tax expense (benefit)		(29)		(2)		246		—		215
Consolidated net income		386		432		437		(867)		388
Less: Net income (loss) attributable to noncontrolling interests		—		—		2		—		2
Net income attributable to Waste Management, Inc.	$	386	$	432	$	435	$	(867)	$	386

CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS (Continued)

Nine Months Ended September 30, 2018

(Unaudited)


			WM		Non‑Guarantor
	WM		Holdings		Subsidiaries		Eliminations		Consolidated
Operating revenues	$	—	$	—	$	11,204	$	(132)	$	11,072
Costs and expenses		132		—		9,050		(132)		9,050
Income from operations		(132)		—		2,154		—		2,022
Other income (expense):
Interest expense, net		(232)		(15)		(30)		—		(277)
Equity in earnings of subsidiaries, net of tax		1,662		1,672		—		(3,334)		—
Other, net		—		—		(28)		—		(28)
		1,430		1,657		(58)		(3,334)		(305)
Income before income taxes		1,298		1,657		2,096		(3,334)		1,717
Income tax expense (benefit)		(96)		(4)		425		—		325
Consolidated net income		1,394		1,661		1,671		(3,334)		1,392
Less: Net income (loss) attributable to noncontrolling interests		—		—		(2)		—		(2)
Net income attributable to Waste Management, Inc.	$	1,394	$	1,661	$	1,673	$	(3,334)	$	1,394

Nine Months Ended September 30, 2017

(Unaudited)


			WM		Non‑Guarantor
	WM		Holdings		Subsidiaries		Eliminations		Consolidated
Operating revenues	$	—	$	—	$	10,833	$	—	$	10,833
Costs and expenses		—		—		8,901		—		8,901
Income from operations		—		—		1,932		—		1,932
Other income (expense):
Interest expense, net		(223)		(15)		(34)		—		(272)
Equity in earnings of subsidiaries, net of tax		1,181		1,190		—		(2,371)		—
Other, net		—		—		(53)		—		(53)
		958		1,175		(87)		(2,371)		(325)
Income before income taxes		958		1,175		1,845		(2,371)		1,607
Income tax expense (benefit)		(88)		(6)		655		—		561
Consolidated net income		1,046		1,181		1,190		(2,371)		1,046
Less: Net income (loss) attributable to noncontrolling interests		—		—		—		—		—
Net income attributable to Waste Management, Inc.	$	1,046	$	1,181	$	1,190	$	(2,371)	$	1,046

Condensed Consolidating Statements of Comprehensive Income

CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME

(Unaudited)


			WM		Non-Guarantor
	WM		Holdings		Subsidiaries		Eliminations		Consolidated
Three Months Ended September 30:
2018
Comprehensive income	$	501	$	588	$	623	$	(1,181)	$	531
Less: Comprehensive income (loss) attributable to noncontrolling interests		—		—		(1)		—		(1)
Comprehensive income attributable to Waste Management, Inc.	$	501	$	588	$	624	$	(1,181)	$	532

2017
Comprehensive income	$	388	$	432	$	482	$	(867)	$	435
Less: Comprehensive income (loss) attributable to noncontrolling interests		—		—		2		—		2
Comprehensive income attributable to Waste Management, Inc.	$	388	$	432	$	480	$	(867)	$	433


			WM		Non-Guarantor
	WM		Holdings		Subsidiaries		Eliminations		Consolidated
Nine Months Ended September 30:
2018
Comprehensive income	$	1,400	$	1,661	$	1,646	$	(3,334)	$	1,373
Less: Comprehensive income (loss) attributable to noncontrolling interests		—		—		(2)		—		(2)
Comprehensive income attributable to Waste Management, Inc.	$	1,400	$	1,661	$	1,648	$	(3,334)	$	1,375

2017
Comprehensive income	$	1,052	$	1,181	$	1,278	$	(2,371)	$	1,140
Less: Comprehensive income (loss) attributable to noncontrolling interests		—		—		—		—		—
Comprehensive income attributable to Waste Management, Inc.	$	1,052	$	1,181	$	1,278	$	(2,371)	$	1,140

Condensed Consolidating Statements of Cash Flows

CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS

Nine Months Ended September 30, 2018

(Unaudited)


			WM		Non-Guarantor
	WM(a)		Holdings(a)		Subsidiaries(a)		Eliminations		Consolidated
Cash flows provided by (used in):
Operating activities	$	—	$	—	$	2,658	$	—	$	2,658
Investing activities		—		—		(1,506)		—		(1,506)
Financing activities		—		—		(1,015)		—		(1,015)
Effect of exchange rate changes on cash, cash equivalents and restricted cash and cash equivalents		—		—		—		—		—
Intercompany activity		—		—		—		—		—
Increase in cash, cash equivalents and restricted cash and cash equivalents		—		—		137		—		137
Cash, cash equivalents and restricted cash and cash equivalents at beginning of period		—		—		293		—		293
Cash, cash equivalents and restricted cash and cash equivalents at end of period	$	—	$	—	$	430	$	—	$	430

Nine Months Ended September 30, 2017

(Unaudited)


			WM		Non-Guarantor
	WM(a)		Holdings(a)		Subsidiaries(a)		Eliminations		Consolidated
Cash flows provided by (used in):
Operating activities	$	—	$	—	$	2,388	$	—	$	2,388
Investing activities		—		—		(1,050)		—		(1,050)
Financing activities		—		—		(1,331)		—		(1,331)
Effect of exchange rate changes on cash, cash equivalents and restricted cash and cash equivalents		—		—		1		—		1
Intercompany activity		—		—		—		—		—
Increase in cash, cash equivalents and restricted cash and cash equivalents		—		—		8		—		8
Cash, cash equivalents and restricted cash and cash equivalents at beginning of period		—		—		94		—		94
Cash, cash equivalents and restricted cash and cash equivalents at end of period	$	—	$	—	$	102	$	—	$	102

(a)

Cash receipts and payments of WM and WM Holdings are transacted by Non-Guarantor Subsidiaries.

Basis of Presentation - Revenue (Detail) $ in Millions	9 Months Ended
Basis of Presentation - Revenue (Detail) $ in Millions	Sep. 30, 2018 USD ($) segment	Jan. 01, 2018 USD ($)	Dec. 31, 2017 USD ($)
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Number of areas \| segment	17
Retained earnings	$ 9,464		$ 8,588
Contract acquisition costs	141
Deferred income taxes	$ 1,245		$ 1,248
Revenue, Practical Expedient, Remaining Performance Obligation [true/false]	true
Accounting Standards Update 2014-09 [Member] \| Impact of adoption [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Retained earnings		$ 80
Contract acquisition costs		108
Deferred income taxes		$ 28

Basis of Presentation (Detail) - USD ($) $ in Millions	Jan. 01, 2018	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2016
New ASU
Restricted trust and escrow accounts		$ 394	$ 319
Accounting Standards Update 2016-01 [Member]
New ASU
Equity investments without readily determinable fair values		$ 85
Accounting Standards Update 2016-15 [Member]
New ASU
Restricted trust and escrow accounts			$ 271	$ 67	$ 62
Accounting Standards Update 2018-02 [Member]
New ASU
Adoption of new accounting standard	$ (5)

Landfill and Environmental Remediation Liabilities - Summary (Detail) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Landfill and environmental remediation liabilities
Total, Environmental Remediation	$ 237
Current (in accrued liabilities)	158	$ 156
Long-term	1,832	1,770
Total	1,990	1,926
Landfill [Member]
Landfill and environmental remediation liabilities
Current (in accrued liabilities), Landfill	131	128
Long-term, Landfill	1,622	1,547
Total, Landfill	1,753	1,675
Environmental Remediation Liabilities [Member]
Landfill and environmental remediation liabilities
Current (in accrued liabilities), Environmental Remediation	27	28
Long-term, Environmental Remediation	210	223
Total, Environmental Remediation	$ 237	$ 251

Landfill and Environmental Remediation Liabilities - Changes (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Landfill and environmental remediation liabilities
Interest accretion	$ 71	$ 68
Ending balance, environmental remediation	237
Asset retirement obligation revision of estimate increase (decrease) related to estimated capping activities	$ 11
Risk-free discount rate of the obligations	3.00%		2.50%
Increase (decrease) operating expenses due to change in discount rate	$ (5)
Landfill [Member]
Landfill and environmental remediation liabilities
Beginning balance, landfill	1,675
Obligations incurred and capitalized	62
Obligations settled	(71)
Interest accretion	71
Revisions in estimates and interest rate assumptions	7
Acquisitions, divestitures and other adjustments	9
Ending balance, landfill	1,753
Environmental Remediation Liabilities [Member]
Landfill and environmental remediation liabilities
Beginning balance, environmental remediation	251
Obligations settled	(18)
Interest accretion	4
Revisions in estimates and interest rate assumptions	2
Acquisitions, divestitures and other adjustments	(2)
Ending balance, environmental remediation	237
San Jacinto Waste Pits [Member]
Landfill and environmental remediation liabilities
Beginning balance, environmental remediation	55
Ending balance, environmental remediation	$ 55

Debt - Components of Debt (Detail) - USD ($) $ in Millions	Sep. 30, 2018	May 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Debt
Debt and capital lease obligations	$ 10,016			$ 9,491
Debt issuance costs, discounts and other	(52)			(56)
Current portion of long-term debt	447			739
Long-term debt, less current portion	9,569			8,752
Revolving Credit Facility [Member]
Debt
Debt and capital lease obligations	44
Credit Facility, aggregate capacity	$ 2,750	$ 2,250
Weighted average interest rate	2.70%
Commercial Paper Program [Member]
Debt
Debt and capital lease obligations	$ 1,053			$ 515
Credit Facility, aggregate capacity	$ 2,750		$ 1,500
Weighted average interest rate	2.40%			1.90%
Canadian Term Loan and Revolving Credit Facility [Member]
Debt
Debt and capital lease obligations				$ 113
Weighted average interest rate				2.50%
Senior Notes, Aggregate [Member]
Debt
Debt and capital lease obligations	$ 6,222			$ 6,222
Weighted average interest rate	4.30%			4.30%
Tax Exempt Bonds [Member]
Debt
Debt and capital lease obligations	$ 2,318			$ 2,370
Current portion of long-term debt	$ 209
Weighted average interest rate	2.20%			2.00%
Capital Leases and Other [Member]
Debt
Debt and capital lease obligations	$ 431			$ 327
Current portion of long-term debt	$ 260
Minimum [Member] \| Senior Notes, Aggregate [Member]
Debt
Interest rate	2.40%
Minimum [Member] \| Tax Exempt Bonds [Member]
Debt
Interest rate	1.35%
Maximum [Member] \| Senior Notes, Aggregate [Member]
Debt
Interest rate	7.75%
Maximum [Member] \| Tax Exempt Bonds [Member]
Debt
Interest rate	4.30%
Maximum [Member] \| Capital Leases and Other [Member]
Debt
Interest rate	12.00%

Debt - Classification and Utilization (Detail) $ in Millions, $ in Millions	9 Months Ended
	Sep. 30, 2018 CAD ($) item	Sep. 30, 2018 USD ($) item	Jul. 31, 2018 CAD ($)	May 31, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Debt
Debt maturing or subject to remarketing within twelve months		$ 2,200
Current portion of long-term debt		447				$ 739
Commercial Paper Program [Member]
Debt
Debt maturing or subject to remarketing within twelve months classified as long-term		955
Maximum capacity		2,750			$ 1,500
Debt, before unamortized (discount) premium		1,100
Debt term	397 days
Tax Exempt Bonds [Member]
Debt
Debt with interest rate periods that expire in the next 12 months		806
Current portion of long-term debt		209
Debt maturing or subject to remarketing within twelve months classified as long-term		761
Variable-rate tax-exempt bonds		268
Canadian Revolving Credit Facility [Member]
Debt
Maximum capacity			$ 50
Canadian Term Loan [Member]
Debt
Maximum term credit			$ 460
Other Letter of Credit Facilities [Member]
Debt
Letters of credit outstanding		541
Capital Leases and Other [Member]
Debt
Current portion of long-term debt		260
Revolving Credit Facility [Member]
Debt
Maximum capacity		2,750		$ 2,250
Accordion option capacity		$ 750
Number of extension periods \| item	2	2
Extension term	1 year
Letters of credit outstanding		$ 606
Unused and available credit capacity		1,000
Credit Facility Revolving, Canadian [Member]
Debt
Maximum capacity		375
Outstanding borrowings under credit facility	$ 57	$ 44

Debt - Borrowings and Repayments (Detail) $ in Millions, $ in Millions		6 Months Ended	8 Months Ended		9 Months Ended
	Sep. 28, 2018 USD ($)	Jun. 30, 2018 USD ($)	Aug. 31, 2018 CAD ($)	Aug. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)
Debt
Net commercial paper borrowings					$ 523	$ 501
Debt repayments					338	$ 749
Revolving Credit Facility [Member]
Debt
Net line of credit proceeds (repayments)		$ 28
Commercial Paper Program [Member]
Debt
Net line of credit proceeds (repayments)					523
Canadian Term Loan [Member]
Debt
Debt repayments			$ 142	$ 109
Tax Exempt Bonds [Member]
Debt
Debt repayments					52
Capital Leases and Other [Member]
Debt
Net debt borrowings (repayments)					35
Capital Leases and Other [Member] \| Investments Qualifying for Federal Tax Credits [Member]
Debt
Capital obligations	$ 139				$ 139

Operating Revenues (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Operating Revenues (Details) - USD ($) $ in Millions	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2017
Contract Acquisition Costs
Revenue other than customer contracts (as a percent)		1.00%	1.00%
Deferred contract costs	$ 141	$ 141
Long-term revenue contracts (as a percent)		30.00%
Weighted average remaining contract term		4 years
Deferred Sales Incentives [Member]
Contract Acquisition Costs
Deferred contract costs	109	$ 109
Selling, General and Administrative Expenses [Member]
Contract Acquisition Costs
Deferred contract costs amortization	6	17
Reduction to Sales [Member]
Contract Acquisition Costs
Deferred contract costs amortization	$ 8	$ 27
Minimum [Member]
Contract Acquisition Costs
Deferred revenue recognition period		1 month
Contract amortization period		5 years
Maximum [Member]
Contract Acquisition Costs
Deferred revenue recognition period		3 months
Contract amortization period		13 years

Income Taxes - Quarter information (Detail) - USD ($) $ in Millions		1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 28, 2018	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Income Taxes
Effective tax rate of income (loss) before income taxes			16.60%	35.70%	18.90%	34.90%
Income tax expense at U.S. federal statutory rate					21.00%		35.00%
Net reduction in income tax expense due to Tax Cuts and Jobs Act		$ (12)
Re-measurement of net deferred tax assets and liabilities due to tax legislation		(7)
Mandatory transition tax due to tax legislation		$ (5)
Increase (decrease) to accruals and related deferred taxes			$ (27)	$ (15)	$ (35)	$ (15)
Equity in net losses of unconsolidated entities			9	8	29	53
Tax audit increase (decrease)			(2)		(35)
Investments Qualifying for Federal Tax Credits [Member]
Income Taxes
Total consideration	$ 157
Payment to acquire investment	18
Equity in net losses of unconsolidated entities			5	6	17	21
Income tax (expense) benefit, including tax credits, from equity method investment			$ 18	$ 14	40	$ 39
Investments Qualifying for Federal Tax Credits [Member] \| Capital Leases and Other [Member]
Income Taxes
Capital obligations	$ 139				$ 139

Earnings Per Share (Detail) - shares shares in Millions	3 Months Ended		9 Months Ended
Earnings Per Share (Detail) - shares shares in Millions	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share
Number of common shares outstanding at year-end	427.1	434.2	427.1	434.2
Effect of using weighted average common shares outstanding	0.8	3.6	3.2	6.1
Weighted average basic common shares outstanding	427.9	437.8	430.3	440.3
Dilutive effect of equity-based compensation awards and other contingently issuable shares	2.9	3.0	2.9	3.0
Weighted average diluted common shares outstanding	430.8	440.8	433.2	443.3
Potentially issuable shares	7.6	8.2	7.6	8.2
Number of anti-dilutive potentially issuable shares excluded from diluted common shares outstanding	1.5	1.9	1.5	2.3

Commitments and Contingencies - Other (Details)	2 Months Ended	9 Months Ended
Commitments and Contingencies - Other (Details)	Jan. 31, 2011 item	Sep. 30, 2018 USD ($) site item	May 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Commitments And Contingencies [Line Items]
Approximate number of homeowners' properties adjacent to or near certain of our landfills with agreements guaranteeing market value \| item		775
Number of landfills adjacent to or near homeowners' properties with agreements guaranteeing market value \| item		18
Environmental remediation reasonably possible additional losses high estimate		$ 140,000,000
Environmental remediation liabilities		$ 237,000,000
Number of sites listed on the EPA's NPL for which we have been notified we are a PRP \| site		75
Number of owned sites listed on the EPA's NPL for which we have been notified we are a PRP \| site		15
Number of non-owned sites listed on the EPA's NPL for which we have been notified we are a PRP \| site		60
Dollar threshold for environmental matters requiring disclosure under item 103 of the SEC's Regulation S-K		$ 100,000
Approximate percentage of workforce covered by collective bargaining agreements		20.00%
Expected time of completion of IRS audits		18 months
San Jacinto Waste Pits [Member]
Commitments And Contingencies [Line Items]
Environmental remediation liabilities		$ 55,000,000		$ 55,000,000
Waimanalo Gulch Sanitary Landfill
Commitments And Contingencies [Line Items]
Number of major rainfalls \| item	2
Wheelabrator [Member]
Commitments And Contingencies [Line Items]
Maximum future payments		85,000,000
Revolving Credit Facility [Member]
Commitments And Contingencies [Line Items]
Credit Facility, aggregate capacity		$ 2,750,000,000	$ 2,250,000,000

Segment and Related Information - Information (Detail)	9 Months Ended
Segment and Related Information - Information (Detail)	Sep. 30, 2018 area segment
Segment Reporting Information [Line Items]
Number of areas	17
Solid Waste [Member]
Segment Reporting Information [Line Items]
Number of areas \| area	17
Number of reportable segments	3

Segment and Related Information - Summary (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Operating revenues	$ 3,822	$ 3,716	$ 11,072	$ 10,833
Income from operations	699	701	2,022	1,932
Operating Group Total [Member]
Segment Reporting Information [Line Items]
Operating revenues	3,822	3,716	11,072	10,833
Income from operations	834	837	2,433	2,370
Solid Waste [Member]
Segment Reporting Information [Line Items]
Operating revenues	3,238	3,118	9,378	9,079
Income from operations	849	853	2,458	2,436
Tier 1 [Member]
Segment Reporting Information [Line Items]
Operating revenues	1,229	1,174	3,577	3,435
Income from operations	416	398	1,176	1,159
Tier 2 [Member]
Segment Reporting Information [Line Items]
Operating revenues	544	546	1,586	1,574
Income from operations	142	142	405	400
Tier 3 [Member]
Segment Reporting Information [Line Items]
Operating revenues	1,465	1,398	4,215	4,070
Income from operations	291	313	877	877
Other [Member]
Segment Reporting Information [Line Items]
Operating revenues	584	598	1,694	1,754
Income from operations	(15)	(16)	(25)	(66)
Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating revenues	4,624	4,465	13,387	12,993
Operating Segments [Member] \| Operating Group Total [Member]
Segment Reporting Information [Line Items]
Operating revenues	4,624	4,465	13,387	12,993
Operating Segments [Member] \| Solid Waste [Member]
Segment Reporting Information [Line Items]
Operating revenues	3,995	3,803	11,538	11,071
Operating Segments [Member] \| Tier 1 [Member]
Segment Reporting Information [Line Items]
Operating revenues	1,506	1,432	4,364	4,189
Operating Segments [Member] \| Tier 2 [Member]
Segment Reporting Information [Line Items]
Operating revenues	671	660	1,947	1,903
Operating Segments [Member] \| Tier 3 [Member]
Segment Reporting Information [Line Items]
Operating revenues	1,818	1,711	5,227	4,979
Operating Segments [Member] \| Other [Member]
Segment Reporting Information [Line Items]
Operating revenues	629	662	1,849	1,922
Intercompany Operating Revenues [Member]
Segment Reporting Information [Line Items]
Operating revenues	(802)	(749)	(2,315)	(2,160)
Intercompany Operating Revenues [Member] \| Operating Group Total [Member]
Segment Reporting Information [Line Items]
Operating revenues	(802)	(749)	(2,315)	(2,160)
Intercompany Operating Revenues [Member] \| Solid Waste [Member]
Segment Reporting Information [Line Items]
Operating revenues	(757)	(685)	(2,160)	(1,992)
Intercompany Operating Revenues [Member] \| Tier 1 [Member]
Segment Reporting Information [Line Items]
Operating revenues	(277)	(258)	(787)	(754)
Intercompany Operating Revenues [Member] \| Tier 2 [Member]
Segment Reporting Information [Line Items]
Operating revenues	(127)	(114)	(361)	(329)
Intercompany Operating Revenues [Member] \| Tier 3 [Member]
Segment Reporting Information [Line Items]
Operating revenues	(353)	(313)	(1,012)	(909)
Intercompany Operating Revenues [Member] \| Other [Member]
Segment Reporting Information [Line Items]
Operating revenues	(45)	(64)	(155)	(168)
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Income from operations	$ (135)	$ (136)	$ (411)	$ (438)

Segment and Related Information - Revenues mix (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenue from External Customer [Line Items]
Operating revenues	$ 3,822	$ 3,716	$ 11,072	$ 10,833
Operating Segments [Member]
Revenue from External Customer [Line Items]
Operating revenues	4,624	4,465	13,387	12,993
Operating Segments [Member] \| Collection [Member]
Revenue from External Customer [Line Items]
Operating revenues	2,486	2,351	7,234	6,912
Operating Segments [Member] \| Commercial [Member]
Revenue from External Customer [Line Items]
Operating revenues	1,007	936	2,948	2,764
Operating Segments [Member] \| Residential [Member]
Revenue from External Customer [Line Items]
Operating revenues	639	635	1,885	1,888
Operating Segments [Member] \| Industrial [Member]
Revenue from External Customer [Line Items]
Operating revenues	723	673	2,068	1,930
Operating Segments [Member] \| Other Collection [Member]
Revenue from External Customer [Line Items]
Operating revenues	117	107	333	330
Operating Segments [Member] \| Landfill [Member]
Revenue from External Customer [Line Items]
Operating revenues	926	884	2,646	2,487
Operating Segments [Member] \| Transfer [Member]
Revenue from External Customer [Line Items]
Operating revenues	445	412	1,257	1,192
Operating Segments [Member] \| Recycling [Member]
Revenue from External Customer [Line Items]
Operating revenues	337	375	954	1,122
Operating Segments [Member] \| Other Revenue [Member]
Revenue from External Customer [Line Items]
Operating revenues	430	443	1,296	1,280
Intercompany Operating Revenues [Member]
Revenue from External Customer [Line Items]
Operating revenues	$ (802)	$ (749)	$ (2,315)	$ (2,160)

Acquisitions and Divestitures (Detail) $ in Millions	9 Months Ended
Acquisitions and Divestitures (Detail) $ in Millions	Sep. 30, 2018 USD ($) item
Acquisitions and Divestitures
Number of business acquired \| item	21
Consideration, net of cash acquired, for business acquisitions	$ 350
Business acquisitions closed during the year, cash payments	329
Other consideration	21
Purchase price holdbacks paid	13
Purchase price holdbacks paid for acquisitions closed in current year	$ 7

Acquisitions and Divestitures - Divestitures (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2018 USD ($)
Divestitures
Gain (loss) on sale of assets	$ 43
Disposed of by Sale, Not Discontinued Operations [Member]
Divestitures
Aggregate sales prices for divestitures of operations	86
Gain (loss) on sale of assets	$ 43

Asset Impairments and Unusual Items - Details (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
(Income) expense from divestitures, asset impairments and unusual items	$ 28	$ 9	$ (14)	$ 10
(Income) expense from divestitures			(43)
Equity method investments impairment charges				$ 28
Landfill [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Asset impairments			$ 29

Accumulated Other Comprehensive Loss - Changes (Detail) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
	Jan. 01, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
AOCI roll forward
Beginning balance	$ 6,042			$ 6,042
Other comprehensive income (loss), net of tax		$ 33	$ 47	(19)	$ 94
Ending balance		6,241		6,241
Accumulated Other Comprehensive Loss [Member]
AOCI roll forward
Beginning balance	8			8
Other comprehensive income (loss) before reclassifications, net of tax				(25)
Amounts reclassified from accumulated other comprehensive (income) loss, net of tax				6
Other comprehensive income (loss), net of tax				(19)
Ending balance		(16)		(16)
Derivative Instruments [Member]
AOCI roll forward
Beginning balance	(33)			(33)
Amounts reclassified from accumulated other comprehensive (income) loss, net of tax				6
Other comprehensive income (loss), net of tax				6
Ending balance		(34)		(34)
Available for sale Securities [Member]
AOCI roll forward
Beginning balance	15			15
Other comprehensive income (loss) before reclassifications, net of tax				8
Other comprehensive income (loss), net of tax				8
Ending balance		26		26
Foreign Currency Translation Adjustments [Member]
AOCI roll forward
Beginning balance	29			29
Other comprehensive income (loss) before reclassifications, net of tax				(33)
Other comprehensive income (loss), net of tax				(33)
Ending balance		(4)		(4)
Post - Retirement Benefit Obligation [Member]
AOCI roll forward
Beginning balance	(3)			(3)
Ending balance		$ (4)		(4)
Accounting Standards Update 2018-02 [Member]
AOCI roll forward
Adoption of new accounting standard	$ (5)
Accounting Standards Update 2018-02 [Member] \| Accumulated Other Comprehensive Loss [Member]
AOCI roll forward
Adoption of new accounting standard				(5)
Accounting Standards Update 2018-02 [Member] \| Derivative Instruments [Member]
AOCI roll forward
Adoption of new accounting standard				(7)
Accounting Standards Update 2018-02 [Member] \| Available for sale Securities [Member]
AOCI roll forward
Adoption of new accounting standard				3
Accounting Standards Update 2018-02 [Member] \| Post - Retirement Benefit Obligation [Member]
AOCI roll forward
Adoption of new accounting standard				$ (1)

Accumulated Other Comprehensive Loss - Tax Impact (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2018 USD ($)
Derivative Instruments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications, tax	$ 0
Amounts reclassified from accumulated other comprehensive (income) loss, tax	2
Available for sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications, tax	3
Amounts reclassified from accumulated other comprehensive (income) loss, tax	0
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications, tax	0
Amounts reclassified from accumulated other comprehensive (income) loss, tax	0
Post - Retirement Benefit Obligation [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications, tax	0
Amounts reclassified from accumulated other comprehensive (income) loss, tax	$ 0

Accumulated Other Comprehensive Income (Loss) - Derivative (Detail) $ in Millions	Sep. 30, 2018 USD ($)
Derivative Instruments [Member] \| Foreign Currency Derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Outstanding derivatives	$ 0

Common Stock Repurchase Program (Detail) $ / shares in Units, shares in Millions, $ in Millions	1 Months Ended		3 Months Ended	6 Months Ended	9 Months Ended
	Oct. 31, 2018 $ / shares shares	Jul. 31, 2018 USD ($) shares	May 31, 2018 USD ($) $ / shares shares	Jun. 30, 2018 USD ($) item shares	Sep. 30, 2018 USD ($) item $ / shares shares	Sep. 30, 2017 USD ($)
Accelerated Share Repurchases [Line Items]
Total repurchases					$ 750.0
Cash paid for repurchase of common stock					750.0	$ 750.0
Authorized share repurchases					$ 500.0
Accelerated Share Repurchase Agreement (ASR) [Member]
Accelerated Share Repurchases [Line Items]
Number of ASR agreements \| item				2	3
Total repurchases		$ 200.0		$ 450.0
Cash paid for repurchase of common stock		$ 200.0
Shares repurchased \| shares	0.4	1.8		5.4	7.2
Weighted average per share purchase price \| $ / shares	$ 90.07				$ 85.04
10b5-1 Plan [Member]
Accelerated Share Repurchases [Line Items]
Total repurchases			$ 100.0
Shares repurchased \| shares			1.2
Weighted average per share purchase price \| $ / shares			$ 83.20

Fair Value Measurements - Recurring (Detail) - USD ($) $ in Millions	1 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Redeemable Preferred Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value adjustment asset	$ 11
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	243	$ 376
Fair Value, Measurements, Recurring [Member] \| Quoted Prices in Active Markets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	82	225
Fair Value, Measurements, Recurring [Member] \| Quoted Prices in Active Markets (Level 1) [Member] \| Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	82	225
Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	95	96
Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Available-for-sale Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	50	49
Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Fixed-Income Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	45	47
Fair Value, Measurements, Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	66	55
Fair Value, Measurements, Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| Redeemable Preferred Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	$ 66	$ 55

Fair Value Measurements - Debt (Detail) - USD ($) $ in Billions	Sep. 30, 2018	Dec. 31, 2017
Reported Value Measurement [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of Debt	$ 10.0	$ 9.5
Significant Other Observable Inputs (Level 2) [Member] \| Estimate of Fair Value Measurement [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of Debt	$ 10.1	$ 9.9

Variable Interest Entities (Detail) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Variable Interest Entity, Not Primary Beneficiary [Member] \| Other Receivables Investments in Unconsolidated Entities and Other Assets [Member]
Variable Interest Entity [Line Items]
Aggregate investment balance	$ 99	$ 99
Investments Qualifying for Federal Tax Credits [Member] \| Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Aggregate investment balance	199	59
Investment In Low Income Housing Properties [Member] \| Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Equity method investments debt balance	156	34
Trust For Final Capping, Closure, Post-closure Or Environmental Remediation Obligations [Member] \| Variable Interest Entity, Primary Beneficiary [Member] \| Long-term other assets [Member]
Variable Interest Entity [Line Items]
Value of consolidated VIEs	$ 103	$ 101

Condensed Consolidating Financial Statements - Balance Sheets (Detail) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
Current assets:
Cash and cash equivalents	$ 83	$ 22	$ 35
Other current assets	2,592	2,602
Total current assets	2,675	2,624
Property and equipment, net	11,815	11,559
Other assets	8,101	7,646
Total assets	22,591	21,829
Current liabilities:
Current portion of long-term debt	447	739
Accounts payable and other current liabilities	2,623	2,523
Total current liabilities	3,070	3,262
Long-term debt, less current portion	9,569	8,752
Other liabilities	3,711	3,773
Total liabilities	16,350	15,787
Equity:
Stockholders' equity	6,239	6,019
Noncontrolling interests	2	23
Total equity	6,241	6,042
Total liabilities and equity	22,591	21,829
Eliminations [Member]
Current assets:
Investments in affiliates	(48,599)	(45,286)
Advances to affiliates	(16,289)	(15,349)
Total assets	(64,888)	(60,635)
Current liabilities:
Due to affiliates	(22,645)	(21,701)
Total liabilities	(22,645)	(21,701)
Equity:
Stockholders' equity	(48,599)	(45,286)
Advances to affiliates	6,356	6,352
Total equity	(42,243)	(38,934)
Total liabilities and equity	(64,888)	(60,635)
WM [Member] \| Reportable Legal Entities [Member]
Current assets:
Other current assets	46	5
Total current assets	46	5
Investments in affiliates	24,055	22,393
Other assets	7	9
Total assets	24,108	22,407
Current liabilities:
Current portion of long-term debt	104	537
Accounts payable and other current liabilities	71	55
Total current liabilities	175	592
Long-term debt, less current portion	7,409	6,457
Due to affiliates	16,353	15,404
Other liabilities	5	8
Total liabilities	23,942	22,461
Equity:
Stockholders' equity	6,239	6,019
Advances to affiliates	(6,073)	(6,073)
Total equity	166	(54)
Total liabilities and equity	24,108	22,407
WM Holdings [Member] \| Reportable Legal Entities [Member]
Current assets:
Other current assets	5	5
Total current assets	5	5
Investments in affiliates	24,544	22,893
Other assets	31	31
Total assets	24,580	22,929
Current liabilities:
Accounts payable and other current liabilities	4	9
Total current liabilities	4	9
Long-term debt, less current portion	304	304
Due to affiliates	219	224
Total liabilities	527	537
Equity:
Stockholders' equity	24,053	22,392
Total equity	24,053	22,392
Total liabilities and equity	24,580	22,929
Non-Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
Current assets:
Cash and cash equivalents	83	22
Other current assets	2,541	2,592
Total current assets	2,624	2,614
Property and equipment, net	11,815	11,559
Advances to affiliates	16,289	15,349
Other assets	8,063	7,606
Total assets	38,791	37,128
Current liabilities:
Current portion of long-term debt	343	202
Accounts payable and other current liabilities	2,548	2,459
Total current liabilities	2,891	2,661
Long-term debt, less current portion	1,856	1,991
Due to affiliates	6,073	6,073
Other liabilities	3,706	3,765
Total liabilities	14,526	14,490
Equity:
Stockholders' equity	24,546	22,894
Advances to affiliates	(283)	(279)
Noncontrolling interests	2	23
Total equity	24,265	22,638
Total liabilities and equity	$ 38,791	$ 37,128

Condensed Consolidating Financial Statements - Statements of Operations (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Condensed Income Statements, Captions [Line Items]
Operating revenues	$ 3,822	$ 3,716	$ 11,072	$ 10,833
Costs and expenses	3,123	3,015	9,050	8,901
Income from operations	699	701	2,022	1,932
Other income (expense):
Interest expense, net	(93)	(90)	(277)	(272)
Other, net	(9)	(8)	(28)	(53)
Total other income (expense)	(102)	(98)	(305)	(325)
Income before income taxes	597	603	1,717	1,607
Income tax expense (benefit)	99	215	325	561
Consolidated net income	498	388	1,392	1,046
Less: Net income (loss) attributable to noncontrolling interests	(1)	2	(2)
Net income attributable to Waste Management, Inc.	499	386	1,394	1,046
Eliminations [Member]
Condensed Income Statements, Captions [Line Items]
Operating revenues	(44)		(132)
Costs and expenses	(44)		(132)
Other income (expense):
Equity in earnings of subsidiaries, net of tax	(1,181)	(867)	(3,334)	(2,371)
Total other income (expense)	(1,181)	(867)	(3,334)	(2,371)
Income before income taxes	(1,181)	(867)	(3,334)	(2,371)
Consolidated net income	(1,181)	(867)	(3,334)	(2,371)
Net income attributable to Waste Management, Inc.	(1,181)	(867)	(3,334)	(2,371)
WM [Member] \| Reportable Legal Entities [Member]
Condensed Income Statements, Captions [Line Items]
Costs and expenses	44		132
Income from operations	(44)		(132)
Other income (expense):
Interest expense, net	(78)	(75)	(232)	(223)
Equity in earnings of subsidiaries, net of tax	589	432	1,662	1,181
Total other income (expense)	511	357	1,430	958
Income before income taxes	467	357	1,298	958
Income tax expense (benefit)	(32)	(29)	(96)	(88)
Consolidated net income	499	386	1,394	1,046
Net income attributable to Waste Management, Inc.	499	386	1,394	1,046
WM Holdings [Member] \| Reportable Legal Entities [Member]
Other income (expense):
Interest expense, net	(6)	(5)	(15)	(15)
Equity in earnings of subsidiaries, net of tax	592	435	1,672	1,190
Total other income (expense)	586	430	1,657	1,175
Income before income taxes	586	430	1,657	1,175
Income tax expense (benefit)	(2)	(2)	(4)	(6)
Consolidated net income	588	432	1,661	1,181
Net income attributable to Waste Management, Inc.	588	432	1,661	1,181
Non-Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
Condensed Income Statements, Captions [Line Items]
Operating revenues	3,866	3,716	11,204	10,833
Costs and expenses	3,123	3,015	9,050	8,901
Income from operations	743	701	2,154	1,932
Other income (expense):
Interest expense, net	(9)	(10)	(30)	(34)
Other, net	(9)	(8)	(28)	(53)
Total other income (expense)	(18)	(18)	(58)	(87)
Income before income taxes	725	683	2,096	1,845
Income tax expense (benefit)	133	246	425	655
Consolidated net income	592	437	1,671	1,190
Less: Net income (loss) attributable to noncontrolling interests	(1)	2	(2)
Net income attributable to Waste Management, Inc.	$ 593	$ 435	$ 1,673	$ 1,190

Condensed Consolidating Financial Statements - Statements of Comprehensive Income (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Condensed Statement Of Income Captions [Line Items]
Comprehensive income	$ 531	$ 435	$ 1,373	$ 1,140
Less: Comprehensive income (loss) attributable to noncontrolling interests	(1)	2	(2)
Comprehensive income attributable to Waste Management, Inc.	532	433	1,375	1,140
Eliminations [Member]
Condensed Statement Of Income Captions [Line Items]
Comprehensive income	(1,181)	(867)	(3,334)	(2,371)
Comprehensive income attributable to Waste Management, Inc.	(1,181)	(867)	(3,334)	(2,371)
WM [Member] \| Reportable Legal Entities [Member]
Condensed Statement Of Income Captions [Line Items]
Comprehensive income	501	388	1,400	1,052
Comprehensive income attributable to Waste Management, Inc.	501	388	1,400	1,052
WM Holdings [Member] \| Reportable Legal Entities [Member]
Condensed Statement Of Income Captions [Line Items]
Comprehensive income	588	432	1,661	1,181
Comprehensive income attributable to Waste Management, Inc.	588	432	1,661	1,181
Non-Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
Condensed Statement Of Income Captions [Line Items]
Comprehensive income	623	482	1,646	1,278
Less: Comprehensive income (loss) attributable to noncontrolling interests	(1)	2	(2)
Comprehensive income attributable to Waste Management, Inc.	$ 624	$ 480	$ 1,648	$ 1,278

Condensed Consolidating Financial Statements - Cash Flows (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Condensed Cash Flow Statements Captions [Line Items]
Operating activities	$ 2,658	$ 2,388
Investing activities	(1,506)	(1,050)
Financing activities	(1,015)	(1,331)
Effect of exchange rate changes on cash, cash equivalents and restricted cash and cash equivalents		1
Increase in cash, cash equivalents and restricted cash and cash equivalents	137	8
Cash, cash equivalents and restricted cash and cash equivalents at beginning of period	293	94
Cash, cash equivalents and restricted cash and cash equivalents at end of period	430	102
Non-Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
Condensed Cash Flow Statements Captions [Line Items]
Operating activities	2,658	2,388
Investing activities	(1,506)	(1,050)
Financing activities	(1,015)	(1,331)
Effect of exchange rate changes on cash, cash equivalents and restricted cash and cash equivalents		1
Increase in cash, cash equivalents and restricted cash and cash equivalents	137	8
Cash, cash equivalents and restricted cash and cash equivalents at beginning of period	293	94
Cash, cash equivalents and restricted cash and cash equivalents at end of period	$ 430	$ 102