Waste Connections (WCN) 10-K 17 Feb 22 2021 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2021	Feb. 04, 2022	Jun. 30, 2021
Document Document and Entity Information [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2021
Document Transition Report	false
Entity File Number	1-34370
Entity Registrant Name	WASTE CONNECTIONS, INC.
Entity Incorporation, State or Country Code	A6
Entity Tax Identification Number	98-1202763
Entity Address, Address Line One	6220 Hwy 7, Suite 600
Entity Address, City or Town	Woodbridge
Entity Address, State or Province	ON
Entity Address, Country	CA
Entity Address, Postal Zip Code	L4H 4G3
City Area Code	(905)
Local Phone Number	532-7510
Title of 12(b) Security	Common Shares, no par value
Trading Symbol	WCN
Security Exchange Name	NYSE
Entity Well Known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Auditor Name	GRANT THORNTON LLP
Auditor Firm ID	248
Auditor Location	Houston, Texas
Entity Shell Company	false
Entity Public Float			$ 31,023,478,489
Entity Common Stock, Shares Outstanding		257,332,581
Entity Central Index Key	0001318220
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2021
Amendment Flag	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets:
Cash and equivalents	$ 147,441	$ 617,294
Accounts receivable, net of allowance for credit losses of $18,480 and $19,380 at December 31, 2021 and 2020, respectively	709,614	630,264
Prepaid expenses and other current assets	175,722	160,714
Total current assets	1,032,777	1,408,272
Restricted cash	72,174	97,095
Restricted investments	59,014	57,516
Property and equipment, net	5,721,949	5,284,506
Operating lease right-of-use assets	160,567	170,923
Goodwill	6,187,643	5,726,650
Intangible assets, net	1,350,597	1,155,079
Other assets, net	115,203	92,323
Total assets	14,699,924	13,992,364
Current liabilities:
Accounts payable	392,868	290,820
Book overdraft	16,721	17,079
Accrued liabilities	442,596	404,923
Current portion of operating lease liabilities	38,017	30,671
Current portion of contingent consideration	62,804	43,297
Deferred revenue	273,720	233,596
Current portion of long-term debt and notes payable	6,020	8,268
Total current liabilities	1,232,746	1,028,654
Long-term portion of debt and notes payable	5,040,500	4,708,678
Long-term portion of operating lease liabilities	129,628	147,223
Long-term portion of contingent consideration	31,504	28,439
Deferred income taxes	850,921	760,044
Other long-term liabilities	421,080	455,888
Total liabilities	7,706,379	7,128,926
Commitments and contingencies (Note 12)
Equity:
Common shares: 260,283,158 shares issued and 260,212,496 shares outstanding at December 31, 2021; 262,899,174 shares issued and 262,824,990 shares outstanding at December 31, 2020	3,693,027	4,030,368
Additional paid-in capital	199,482	170,555
Accumulated other comprehensive loss	39,584	(651)
Treasury shares: 70,662 and 74,184 shares at December 31, 2021 and 2020, respectively
Retained earnings	3,056,845	2,659,001
Total Waste Connections' equity	6,988,938	6,859,273
Noncontrolling interest in subsidiaries	4,607	4,165
Total equity	6,993,545	6,863,438
Total liabilities and shareholders' equity	$ 14,699,924	$ 13,992,364

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Allowance for credit losses	$ 18,480	$ 19,380
Common shares, shares issued	260,283,158	262,899,174
Common shares, shares outstanding	260,212,496	262,824,990
Treasury shares	70,662	74,184

Consolidated Statements of Net

Consolidated Statements of Net Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Statement [Abstract]
Revenues	$ 6,151,361	$ 5,445,990	$ 5,388,679
Operating expenses:
Cost of operations	3,654,074	3,276,808	3,198,757
Selling, general and administrative	612,337	537,632	546,278
Depreciation	673,730	621,102	618,396
Amortization of intangibles	139,279	131,302	125,522
Impairments and other operating items	32,316	466,718	61,948
Operating income	1,039,625	412,428	837,778
Interest expense	(162,796)	(162,375)	(147,368)
Interest income	2,916	5,253	9,777
Other income (expense), net	6,285	(1,392)	5,704
Loss on early extinguishment of debt	(115,288)
Income before income tax provision	770,742	253,914	705,891
Income tax provision	(152,253)	(49,922)	(139,210)
Net income	618,489	203,992	566,681
Plus (Less): Net loss (income) attributable to noncontrolling interests	(442)	685	160
Net income attributable to Waste Connections	$ 618,047	$ 204,677	$ 566,841
Earnings per common share attributable to Waste Connections' common shareholders:
Basic	$ 2.37	$ 0.78	$ 2.15
Diluted	$ 2.36	$ 0.78	$ 2.14
Shares used in the per share calculations:
Basic	261,166,723	263,189,699	263,792,693
Diluted	261,728,470	263,687,539	264,526,561
Cash dividends per common share	$ 0.845	$ 0.760	$ 0.665

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net income	$ 618,489	$ 203,992	$ 566,681
Other comprehensive income (loss), before tax:
Foreign currency translation adjustment	8,183	50,653	101,970
Other comprehensive income (loss), before tax	51,791	(4,233)	50,070
Income tax benefit related to items of other comprehensive income (loss)	(11,556)	14,545	13,753
Other comprehensive income (loss), net of tax	40,235	10,312	63,823
Comprehensive income	658,724	214,304	630,504
Plus (less): Comprehensive loss (income) attributable to noncontrolling interests	(442)	685	160
Comprehensive income attributable to Waste Connections	658,282	214,989	630,664
Interest Rate Swap [Member]
Other comprehensive income (loss), before tax:
Amounts reclassified, gross	20,321	9,778	(8,027)
Change in fair value, gross	$ 23,287	$ (64,664)	$ (43,873)

Consolidated Statements of Equi

Consolidated Statements of Equity - USD ($) $ in Thousands	Deferred Compensation Plan [Member]Common Stock [Member]	Performance Shares [Member]Common Stock [Member]	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]	Retained Earnings [Member]Cumulative Effect, Period of Adoption, Adjustment [Member]	Retained Earnings [Member]	Noncontrolling Interests [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member]	Total
Cumulative effect adjustment from adoption of new accounting pronouncement			$ 4,131,307	$ 133,577	$ (74,786)			$ 2,264,510	$ 5,580		$ 6,460,188
Beginning Balances at Dec. 31, 2018			$ 4,131,307	133,577	(74,786)			2,264,510	5,580		6,460,188
Beginning Balances, shares at Dec. 31, 2018			263,141,413
Beginning Balance, treasury shares at Dec. 31, 2018						129,889
Sale of common shares held in trust			$ 4,036								4,036
Sale of common shares held in trust, shares			48,375			(48,375)
Vesting of restricted share units (shares)	16,375	180,258	416,691
Tax withholdings related to net share settlements of equity-based compensation				(17,660)							(17,660)
Tax withholdings related to net share settlements of equity-based compensation, shares			(210,018)
Equity-based compensation				39,000							$ 39,000
Exercise of warrants, shares			25,067
Repurchase of common shares, shares											0
Cash dividends on common shares								(175,067)			$ (175,067)
Amounts reclassified into earnings, net of taxes					(5,900)						(5,900)
Changes in fair value of cash flow hedges, net of taxes					(32,247)						(32,247)
Foreign currency translation adjustment					101,970						101,970
Distributions to noncontrolling interests									(570)		(570)
Net income (loss)								566,841	(160)		566,681
Ending Balances at Dec. 31, 2019			$ 4,135,343	154,917	(10,963)		$ (2,077)	2,654,207	4,850	$ (2,077)	6,938,354
Ending Balances, Shares at Dec. 31, 2019			263,618,161
Ending Balance, treasury shares at Dec. 31, 2019						81,514
Cumulative effect adjustment from adoption of new accounting pronouncement			$ 4,135,343	154,917	(10,963)		$ (2,077)	2,654,207	4,850	$ (2,077)	6,938,354
Sale of common shares held in trust			$ 679								679
Sale of common shares held in trust, shares			7,330			(7,330)
Vesting of restricted share units (shares)	23,857	281,186	377,006
Fair value adjustment for common shares in deferred compensation plan exchanged for other investment options				(678)							(678)
Tax withholdings related to net share settlements of equity-based compensation				(23,446)							(23,446)
Tax withholdings related to net share settlements of equity-based compensation, shares			(230,698)
Equity-based compensation				39,762							39,762
Exercise of warrants, shares			20,125
Repurchase of common shares			$ (105,654)								$ (105,654)
Repurchase of common shares, shares			(1,271,977)								(1,271,977)
Cash dividends on common shares								(199,883)			$ (199,883)
Amounts reclassified into earnings, net of taxes					7,187						7,187
Changes in fair value of cash flow hedges, net of taxes					(47,528)						(47,528)
Foreign currency translation adjustment					50,653						50,653
Net income (loss)								204,677	(685)		203,992
Ending Balances at Dec. 31, 2020			$ 4,030,368	170,555	(651)			2,659,001	4,165		$ 6,863,438
Ending Balances, Shares at Dec. 31, 2020			262,824,990								262,824,990
Ending Balance, treasury shares at Dec. 31, 2020						74,184					74,184
Cumulative effect adjustment from adoption of new accounting pronouncement			$ 4,030,368	170,555	(651)			2,659,001	4,165		$ 6,863,438
Sale of common shares held in trust			$ 430								430
Sale of common shares held in trust, shares			3,522			(3,522)
Vesting of restricted share units (shares)	19,510	154,251	343,480
Fair value adjustment for common shares in deferred compensation plan exchanged for other investment options				(1,177)							(1,177)
Tax withholdings related to net share settlements of equity-based compensation				(18,606)							(18,606)
Tax withholdings related to net share settlements of equity-based compensation, shares			(186,978)
Equity-based compensation				48,710							48,710
Exercise of warrants, shares			46,730
Issuance of shares under employee share purchase plan			$ 1,222								$ 1,222
Issuance of shares under employee share purchase plan, shares			10,813								10,813
Repurchase of common shares			$ (338,993)								$ (338,993)
Repurchase of common shares, shares			(3,003,822)								(3,003,822)
Cash dividends on common shares								(220,203)			$ (220,203)
Amounts reclassified into earnings, net of taxes					14,936						14,936
Changes in fair value of cash flow hedges, net of taxes					17,116						17,116
Foreign currency translation adjustment					8,183						8,183
Net income (loss)								618,047	442		618,489
Ending Balances at Dec. 31, 2021			$ 3,693,027	199,482	39,584			3,056,845	4,607		$ 6,993,545
Ending Balances, Shares at Dec. 31, 2021			260,212,496								260,212,496
Ending Balance, treasury shares at Dec. 31, 2021						70,662					70,662
Cumulative effect adjustment from adoption of new accounting pronouncement			$ 3,693,027	$ 199,482	$ 39,584			$ 3,056,845	$ 4,607		$ 6,993,545

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 618,489	$ 203,992	$ 566,681
Adjustments to reconcile net income to net cash provided by operating activities:
Loss on disposal of assets and impairments	27,727	445,647	60,592
Depreciation	673,730	621,102	618,396
Amortization of intangibles	139,279	131,302	125,522
Loss on early extinguishment of debt	115,288
Deferred income taxes, net of acquisitions	14,563	(50,487)	54,637
Current period provision for credit losses	9,719	15,509	11,973
Amortization of debt issuance costs	5,055	7,509	5,001
Share-based compensation	58,221	45,751	42,671
Interest accretion	15,970	17,205	16,426
Payment of contingent consideration recorded in earnings	(520)	(10,371)
Adjustments to contingent consideration	2,954	18,418	1,498
Other	(1,260)	2,426	(2,240)
Changes in operating assets and liabilities, net of effects from acquisitions:
Accounts receivable, net	(54,688)	31,332	(34,906)
Prepaid expenses and other current assets	(8,229)	(17,749)	9,135
Accounts payable	66,752	(148,362)	71,147
Deferred revenue	31,707	14,981	19,156
Accrued liabilities	3,853	88,612	(22,938)
Capping, closure and post-closure expenditures	(21,040)	(6,484)	(5,062)
Other long-term liabilities	659	(1,812)	2,858
Net cash provided by operating activities	1,698,229	1,408,521	1,540,547
CASH FLOWS FROM INVESTING ACTIVITIES:
Payments for acquisitions, net of cash acquired	(960,449)	(388,789)	(736,610)
Capital expenditures for property and equipment	(744,315)	(597,053)	(634,406)
Capital expenditure for undeveloped landfill property		(67,508)	(31,683)
Investment in noncontrolling interest	(25,000)		(25,000)
Proceeds from disposal of assets	42,768	19,084	3,566
Other	(6,486)	(11,777)	(1,873)
Net cash used in investing activities	(1,693,482)	(1,046,043)	(1,426,006)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from long-term debt	2,112,193	1,815,625	1,575,795
Principal payments on notes payable and long-term debt	(1,893,100)	(1,542,958)	(1,470,711)
Premiums paid on early extinguishment of debt	(110,617)
Payment of contingent consideration recorded at acquisition date	(12,934)	(12,566)	(3,200)
Change in book overdraft	(367)	1,096	(2,564)
Payments for repurchase of common shares	(338,993)	(105,654)
Payments for cash dividends	(220,203)	(199,883)	(175,067)
Tax withholdings related to net share settlements of equity-based compensation	(18,606)	(23,446)	(17,660)
Debt issuance costs	(18,521)	(11,117)	(5,953)
Proceeds from issuance of shares under employee share purchase plan	1,222
Proceeds from sale of common shares held in trust	430	679	4,036
Distributions to noncontrolling interests			(570)
Net cash used in financing activities	(499,496)	(78,224)	(95,894)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(25)	6,914	608
Net increase (decrease) in cash, cash equivalents and restricted cash	(494,774)	291,168	19,255
Cash, cash equivalents and restricted cash at beginning of year	714,389	423,221	403,966
Cash, cash equivalents and restricted cash at end of year	219,615	714,389	423,221
SUPPLEMENTARY DISCLOSURES OF CASH FLOW INFORMATION AND NON-CASH TRANSACTIONS:
Cash paid for income taxes	146,198	104,618	81,049
Cash paid for interest	157,485	142,310	139,694
Changes in accrued capital expenditures for property and equipment	22,153	(10,940)	(7,528)
In connection with its acquisitions, the Company assumed liabilities as follows:
Fair value of assets acquired	1,230,396	514,234	913,793
Payments for acquisitions, net of cash acquired	(960,449)	(388,789)	(736,610)
Change in open working capital settlements at year end		(1,505)	(5,272)
Liabilities assumed and notes payable issued to sellers of businesses acquired	$ 269,947	$ 123,940	$ 171,911

Business

Business	12 Months Ended
	Dec. 31, 2021
Business [Abstract]
Business	1. BUSINESS The financial statements presented in this report represent the consolidation of Waste Connections, Inc., a corporation organized under the laws of Ontario, Canada, and its wholly-owned and majority-owned subsidiaries. When the terms the “Company” or “Waste Connections” are used in this document, those terms refer to Waste Connections, Inc. and its consolidated subsidiaries. All significant intercompany accounts and transactions have been eliminated in consolidation. The Company is an integrated solid waste services company that provides non-hazardous waste collection, transfer and disposal services, along with resource recovery primarily through recycling and renewable

New Accounting Standards and Re

New Accounting Standards and Reclassifications	12 Months Ended
	Dec. 31, 2021
New Accounting Standards and Reclassifications [Abstract]
New Accounting Standards and Reclassifications	2. NEW ACCOUNTING STANDARDS AND RECLASSIFICATIONS Accounting Standards Adopted Income Taxes – Simplifying the Accounting for Income Taxes . In December 2019, the Financial Accounting Standards Board (“FASB”) issued guidance that simplifies the accounting for income taxes as part of its overall initiative to reduce complexity in applying accounting standards while maintaining or improving the usefulness of the information provided to users of financial statements. The amendments include removal of certain exceptions to the general principles of income taxes, and simplification in several other areas such as accounting for a franchise tax that is partially based on income. The standard is effective for public business entities that are U.S. Securities and Exchange Commission (“SEC”) filers for annual periods beginning after December 15, 2020, and interim periods within those reporting periods. The Company adopted the new standard as of January 1, 2021. SEC amends MD&A and other Regulation S-K disclosure requirements The Company complied with the new rules as of December 31, 2021. Accounting Standards Pending Adoption Reference Rate Reform – Facilitation of the Effects of Reference Rate Reform on Financial Reporting . In March 2020, the FASB issued guidance to provide temporary optional expedients and exceptions to the guidance in GAAP on contract modifications and hedge accounting to ease the financial reporting burdens related to the expected market transition from the London Interbank Offered Rate (“LIBOR”) and other interbank offered rates to alternative reference rates, such as the Secured Overnight Financing Rate (“SOFR”). One-week and two-month U.S. dollar LIBOR settings as well as all non-U.S. dollar LIBOR settings stopped being published on December 31, 2021, while the remaining U.S. dollar LIBOR settings will be discontinued on June 30, 2023. Under the new guidance, entities can elect not to apply certain modification accounting requirements to contracts affected by reference rate reform, if certain criteria are met. An entity that makes this election would not have to remeasure the contracts at the modification date or reassess a previous accounting determination. Under the guidance, entities can also elect various optional expedients that would allow them to continue applying hedge accounting for hedging relationships affected by reference rate reform, if certain criteria are met. The guidance is effective upon issuance. The guidance on contract modifications is applied prospectively from March 12, 2020. It may also be applied to modifications of existing contracts made earlier in the interim period that includes the effective date. The guidance on hedging is applied to eligible hedging relationships existing as of the beginning of the interim period that includes the effective date and to new eligible hedging relationships entered into after the beginning of that interim period. The relief is temporary and generally cannot be applied to contract modifications that occur after December 31, 2022 or hedging relationships entered into or evaluated after that date. However, certain optional expedients can be applied to hedging relationships evaluated in periods after December 31, 2022. The Company is currently assessing the potential impact of implementing this new guidance on its consolidated financial statements This relief is expected to permit the Company to maintain cash flow ‎hedge accounting as described in Note 3. Reclassification Cash flow statement information reported in the Company’s prior year periods has been reclassified to conform with the 2021 presentation.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2021
Summary of Significant Accounting Policies [Abstract]
Summary of Significant Accounting Policies	3. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Reporting Currency The functional currency of the Company, as the parent corporate entity, and its operating subsidiaries in the United States, is the U.S. dollar. The functional currency of the Company’s Canadian operations is the Canadian dollar. The reporting currency of the Company is the U.S. dollar. The Company’s consolidated Canadian dollar financial position is translated to U.S. dollars by applying the foreign currency exchange rate in effect at the consolidated balance sheet date. The Company’s consolidated Canadian dollar results of operations and cash flows are translated to U.S. dollars by applying the average foreign currency exchange rate in effect during the reporting period. The resulting translation adjustments are included in other comprehensive income or loss. Gains and losses from foreign currency transactions are included in earnings for the period. Cash Equivalents The Company considers all highly liquid investments with a maturity of three months or less at purchase to be cash equivalents. As of December 31, 2021 and 2020, cash equivalents consisted of demand money market accounts. Concentrations of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and equivalents, restricted cash, restricted investments and accounts receivable. The Company maintains cash and equivalents with banks that at times exceed applicable insurance limits. The Company reduces its exposure to credit risk by maintaining such deposits with high quality financial institutions. The Company’s restricted cash and restricted investments are invested primarily in money market accounts, bank time deposits, U.S. government and agency securities and Canadian bankers’ acceptance notes. The Company has not experienced any losses related to its cash and equivalents, restricted cash or restricted investment accounts. The Company generally does not require collateral on its trade receivables. Credit risk on accounts receivable is minimized as a result of the large and diverse nature of the Company’s customer base. The Company maintains allowances for credit losses based on the expected collectability of accounts receivable. Revenue Recognition and Accounts Receivable The Company’s operations primarily consist of providing non-hazardous waste collection, transfer, disposal and recycling services, E&P services, and intermodal services. The following table disaggregates the Company’s revenues by service line for the periods indicated: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 2020 2019 Commercial $ 1,813,426 ​ $ 1,610,313 $ 1,593,217 Residential ​ ​ 1,673,819 ​ ​ 1,528,217 ​ ​ 1,380,763 Industrial and construction roll off ​ ​ 954,181 ​ ​ 833,148 ​ ​ 841,173 Total collection ​ ​ 4,441,426 ​ ​ 3,971,678 ​ ​ 3,815,153 Landfill ​ ​ 1,233,499 ​ ​ 1,146,732 ​ ​ 1,132,935 Transfer ​ ​ 859,113 ​ ​ 777,754 ​ ​ 771,316 Recycling ​ ​ 205,076 ​ ​ 86,389 ​ ​ 64,245 E&P ​ ​ 138,707 ​ ​ 159,438 ​ ​ 271,887 Intermodal and other ​ ​ 152,194 ​ ​ 118,396 ​ ​ 121,137 Intercompany ​ ​ (878,654) ​ ​ (814,397) ​ ​ (787,994) Total $ 6,151,361 ​ $ 5,445,990 $ 5,388,679 ​ The factors that impact the timing and amount of revenue recognized for each service line may vary based on the nature of the service performed. Generally, the Company recognizes revenue at the time it performs a service. In the event that the Company bills for services in advance of performance, it recognizes deferred revenue for the amount billed and subsequently recognizes revenue at the time the service is provided. See Note 17 for additional information regarding revenue by reportable segment. Revenue by Service Line Solid Waste Collection The Company’s solid waste collection business involves the collection of waste from residential, commercial and industrial customers for transport to transfer stations, or directly to landfills or recycling centers. Solid waste collection services include both recurring and temporary customer relationships. The services are performed under service agreements, municipal contracts or franchise agreements with governmental entities. Existing franchise agreements and most of the existing municipal contracts give the Company the exclusive right to provide specified waste services in the specified territory during the contract term. These exclusive arrangements are awarded, at least initially, on a competitive bid basis and subsequently on a bid or negotiated basis. The standard customer service agreements generally range from one In general, residential collection fees are billed monthly or quarterly in advance. Substantially all of the deferred revenue recorded as of September 30, 2021 was recognized as revenue during the three months ended December 31, 2021 when the service was performed. Commercial customers are typically billed on a monthly basis based on the nature of the services provided during the period. Revenue recognized under these agreements is variable in nature based on the number of residential homes or businesses serviced during the period, the frequency of collection and the volume of waste collected. In addition, certain contracts have annual price escalation clauses that are tied to changes in an underlying base index such as a consumer price index which are unknown at contract inception. Solid waste collection revenue from sources other than customer contracts primarily relates to lease revenue associated with compactors. Revenue from these leasing arrangements was not material and represented an insignificant amount of total revenue for each of the reported periods. Landfill and Transfer Station Revenue at landfills is primarily generated by charging tipping fees on a per ton and/or per yard basis to third parties based on the volume disposed and the nature of the waste. In general, fees are variable in nature and revenue is recognized at the time the waste is disposed at the facility. Revenue at transfer stations is primarily generated by charging tipping or disposal fees on a per ton and/or per yard basis. The fees charged to third parties are based primarily on the market, type and volume or weight of the waste accepted, the distance to the disposal facility and the cost of disposal. In general, fees are billed and revenue is recognized at the time the service is performed. Revenue recognized under these agreements is variable in nature based on the volume of waste accepted at the transfer facility. Many of the Company’s landfill and transfer station customers have entered into one Solid Waste Recycling Solid waste recycling revenues result from the sale of recycled commodities, which are generated by offering residential, commercial, industrial and municipal customers recycling services for a variety of recyclable materials, including compost, cardboard, mixed paper, plastic containers, glass bottles and ferrous and aluminum metals. The Company owns and operates recycling operations and markets collected recyclable materials to third parties for processing before resale. In some instances, the Company utilizes a third party to market recycled materials. In certain instances, the Company issues recycling rebates to municipal or commercial customers, which can be based on the price it receives upon the sale of recycled commodities, a fixed contractual rate or other measures. The Company also receives rebates when it disposes of recycled commodities at third-party facilities. The fees received are based primarily on the market, type and volume or weight of the materials sold. In general, fees are billed and revenue is recognized at the time title is transferred. Revenue recognized under these agreements is variable in nature based on the volume of materials sold. In addition, the amount of revenue recognized is based on commodity prices at the time of sale, which are unknown at contract inception. E&P Waste Treatment, Recovery and Disposal E&P waste revenue is primarily generated through the treatment, recovery and disposal of non-hazardous exploration and production waste from vertical and horizontal drilling, hydraulic fracturing, production and clean-up activity, as well as other services. Revenue recognized under these agreements is variable in nature based on the volume of waste accepted or processed during the period. Intermodal and Other Intermodal revenue is primarily generated through providing intermodal services for the rail haul movement of cargo and solid waste containers in the Pacific Northwest through a network of intermodal facilities. The fees received for intermodal services are based on negotiated rates and vary depending on volume commitments by the shipper and destination. In general, fees are billed and revenue is recognized upon delivery. Other revenues consist primarily of the sale of methane gas and renewable energy credits generated from the Company’s MSW landfills. Revenue Recognition Service obligations of a long-term nature, e.g., solid waste collection service contracts, are satisfied over time, and revenue is recognized based on the value provided to the customer during the period. The amount billed to the customer is based on variable elements such as the number of residential homes or businesses for which collection services are provided, the volume of waste collected, transported and disposed, and the nature of the waste accepted. The Company does not disclose the value of unsatisfied performance obligations for these contracts as its 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. Additionally, certain elements of long-term customer contracts are unknown upon entering into the contract, including the amount that will be billed in accordance with annual price escalation clauses, fuel recovery fee programs and commodity prices. The amount to be billed is often tied to changes in an underlying base index such as a consumer price index or a fuel or commodity index, and revenue is recognized once the index is established for the period. Accounts Receivable Accounts receivable are recorded when billed or accrued and represent claims against third parties that will be settled in cash. The carrying value of the Company’s receivables, net of the allowance for credit losses, represents their estimated net realizable value. The allowance for credit losses is based on management’s assessment of the collectability of assets pooled together with similar risk characteristics. The Company monitors the collectability of its trade receivables as one overall pool due to all trade receivables having similar risk characteristics. The Company estimates its allowance for credit losses based on historical collection trends, the age of outstanding receivables, geographical location of the customer, existing economic conditions and reasonable forecasts. 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 the Company’s internal collection efforts have been unsuccessful in collecting the amount due. The following is a rollforward of the Company’s allowance for credit losses for the periods indicated: ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2021 2020 Beginning balance ​ $ 19,380 ​ $ 16,432 Current period provision for expected credit losses ​ ​ 9,719 ​ ​ 15,509 Write-offs charged against the allowance ​ ​ (15,545) ​ ​ (18,318) Recoveries collected ​ ​ 4,918 ​ ​ 5,720 Impact of changes in foreign currency ​ ​ 8 ​ ​ 37 Ending balance ​ $ 18,480 ​ $ 19,380 ​ Contract Acquisition Costs The incremental direct costs of obtaining a contract, which consist of sales incentives, are recognized as Other assets in the Company’s Consolidated Balance Sheet, and are amortized to Selling, general and administrative expense over the estimated life of the relevant customer relationship, which ranges from one would have recognized is one year or less. The Company had $18,954 and $19,669 of deferred sales incentives at December 31, 2021 and 2020, respectively. During the years ended December 31, 2021, 2020 and 2019, the Company recorded a total of $23,671, $17,138 and $19,673, respectively, of sales incentive amortization expense for deferred sales incentives and sales incentive expense for contracts with original terms of less than one year. Property and Equipment Property and equipment are stated at cost. Improvements or betterments, not considered to be maintenance and repair, which add new functionality or significantly extend the life of an asset are capitalized. Third-party expenditures related to pending development projects, such as legal and engineering expenses, are capitalized. Expenditures for maintenance and repair costs, including planned major maintenance activities, are charged to expense as incurred. The cost of assets retired or otherwise disposed of and the related accumulated depreciation are eliminated from the accounts in the year of disposal. Gains and losses resulting from disposals of property and equipment are recognized in the period in which the property and equipment is disposed. Depreciation is computed using the straight-line method over the estimated useful lives of the assets or the lease term, whichever is shorter. The estimated useful lives are as follows: ​ ​ ​ ​ Buildings 10 Leasehold and land improvements 3 Machinery and equipment 3 Rolling stock 3 Containers 3 ​ Landfill Accounting The Company utilizes the life cycle method of accounting for landfill costs. This method applies the costs to be capitalized associated with acquiring, developing, closing and monitoring the landfills over the associated consumption of landfill capacity. The Company utilizes the units of consumption method to amortize landfill development costs over the estimated remaining capacity of a landfill. Under this method, the Company includes future estimated construction costs using current dollars, as well as costs incurred to date, in the amortization base. When certain criteria are met, the Company includes expansion airspace, which has not been permitted, in the calculation of the total remaining capacity of the landfill. - Landfill development costs - Final capping, closure and post-closure obligations a landfill facility ceases to accept waste and closes. Accruals for final capping, closure and post-closure monitoring and maintenance requirements in the U.S. consider site inspection, groundwater monitoring, leachate management, methane gas control and recovery, and operating and maintenance costs to be incurred during the period after the facility closes. Certain of these environmental costs, principally capping and methane gas control costs, are also incurred during the operating life of the site in accordance with the landfill operation requirements of Subtitle D and the air emissions standards. Daily maintenance activities, which include many of these costs, are expensed as incurred during the operating life of the landfill. Daily maintenance activities include leachate disposal; surface water, groundwater, and methane gas monitoring and maintenance; other pollution control activities; mowing and fertilizing the landfill final cap; fence and road maintenance; and third-party inspection and reporting costs. Site specific final capping, closure and post-closure engineering cost estimates are prepared annually for landfills owned or landfills operated under life-of-site agreements by the Company. The net present value of landfill final capping, closure and post-closure liabilities are calculated by estimating the total obligation in current dollars, inflating the obligation based upon the expected date of the expenditure and discounting the inflated total to its present value using a credit-adjusted risk-free rate. Any changes in expectations that result in an upward revision to the estimated undiscounted cash flows are treated as a new liability and are inflated and discounted at rates reflecting current market conditions. Any changes in expectations that result in a downward revision (or no revision) to the estimated undiscounted cash flows result in a liability that is inflated and discounted at rates reflecting the market conditions at the time the cash flows were originally estimated. This policy results in the Company’s final capping, closure and post-closure liabilities being recorded in “layers.” The Company’s discount rate assumption for purposes of computing 2021 and 2020 “layers” for final capping, closure and post-closure obligations was 3.25% and 4.75%, respectively, which reflects the Company’s long-term credit adjusted risk free rate. The Company’s inflation rate assumption was 2.25% and 2.50% for the years ended December 31, 2021 and 2020, respectively. In accordance with the accounting guidance on asset retirement obligations, the final capping, closure and post-closure liability is recorded on the balance sheet along with an offsetting addition to site costs which is amortized to depletion expense on a units-of-consumption basis as remaining landfill airspace is consumed. The impact of changes determined to be changes in estimates, based on an annual update, is accounted for on a prospective basis. Depletion expense resulting from final capping, closure and post-closure obligations recorded as a component of landfill site costs will generally be less during the early portion of a landfill’s operating life and increase thereafter. Owned landfills and landfills operated under life-of-site agreements have estimated remaining lives, based on remaining permitted capacity, probable expansion capacity and projected annual disposal volumes, that range from approximately 1 to 282 years, with approximately 90% of the projected annual disposal volume from landfills with remaining lives of less than 70 years. The costs for final capping, closure and post-closure obligations at landfills the Company owns or operates under life-of-site agreements are generally estimated based on interpretations of current requirements and proposed or anticipated regulatory changes. The following is a reconciliation of the Company’s final capping, closure and post-closure liability balance from December 31, 2019 to December 31, 2021: ​ ​ ​ ​ ​ Final capping, closure and post-closure liability at December 31, 2019 $ 291,474 Liability adjustments ​ 2,490 Accretion expense associated with landfill obligations ​ 14,874 Closure payments ​ (6,488) Assumption of closure liabilities from acquisitions ​ 2,136 Disposition of closure liabilities from divested operations ​ ​ (3,413) Foreign currency translation adjustment ​ ​ 823 Final capping, closure and post-closure liability at December 31, 2020 ​ 301,896 Liability adjustments ​ (1,081) Accretion expense associated with landfill obligations ​ 14,333 Closure payments ​ (21,040) Assumption of closure liabilities from acquisitions ​ ​ 11,380 Disposition of closure liabilities from divested operations ​ ​ (3,566) Foreign currency translation adjustment ​ 615 Final capping, closure and post-closure liability at December 31, 2021 ​ $ 302,537 ​ Liability adjustments of $1,081 and $2,490 for the years ended December 31, 2021 and 2020, respectively, represent non-cash changes to final capping, closure and post-closure liabilities and are recorded on the Consolidated Balance Sheets along with an offsetting addition to site costs, which is amortized to depletion expense as the remaining landfill airspace is consumed. The final capping, closure and post-closure liability is included in Other long-term liabilities in the Consolidated Balance Sheets. The Company performs its annual review of its cost and capacity estimates in the first quarter of each year. - Disposal capacity 1) whether the land where the expansion is being sought is contiguous to the current disposal site, and the Company either owns the expansion property or has rights to it under an option, purchase, operating or other similar agreement; 2) whether total development costs, final capping costs, and closure/post-closure costs have been determined; 3) whether internal personnel have performed a financial analysis of the proposed expansion site and have determined that it has a positive financial and operational impact; 4) whether internal personnel or external consultants are actively working to obtain the necessary approvals to obtain the landfill expansion permit; and 5) whether the Company considers it probable that the Company will achieve the expansion (for a pursued expansion to be considered probable, there must be no significant known technical, legal, community, business, or political restrictions or similar issues existing that the Company believes are more likely than not to impair the success of the expansion). It is possible that the Company’s estimates or assumptions could ultimately be significantly different from actual results. In some cases, the Company may be unsuccessful in obtaining an expansion permit or the Company may determine that an expansion permit that the Company previously thought was probable has become unlikely. To the extent that such estimates, or the assumptions used to make those estimates, prove to be significantly different than actual results, or the belief that the Company will receive an expansion permit changes adversely in a significant manner, the costs of the landfill, including the costs incurred in the pursuit of the expansion, may be subject to impairment testing, as described below, and lower profitability may be experienced due to higher amortization rates, higher capping, closure and post-closure rates, and higher expenses or asset impairments related to the removal of previously included expansion airspace. The Company periodically evaluates its landfill sites for potential impairment indicators. The Company’s judgments regarding the existence of impairment indicators are based on regulatory factors, market conditions and operational performance of its landfills. Future events could cause the Company to conclude that impairment indicators exist and that its landfill carrying costs are impaired. Business Combination Accounting The Company accounts for business combinations as follows: ● ● Finite-Lived Intangible Assets The amounts assigned to franchise agreements, contracts, customer lists, permits and other agreements are being amortized over the expected term of the related agreements (ranging from 1 Goodwill and Indefinite-Lived Intangible Assets The Company acquired indefinite-lived intangible assets in connection with certain of its acquisitions. The amounts assigned to indefinite-lived intangible assets consist of the value of certain perpetual rights to provide solid waste collection and transportation services in specified territories and to operate E&P waste treatment and disposal facilities. The Company measures and recognizes acquired indefinite-lived intangible assets at their estimated acquisition date fair values. Indefinite-lived intangible assets are not amortized. Goodwill represents the excess of: (a) the aggregate of the fair value of consideration transferred, the fair value of any noncontrolling interest in the acquiree (if any) and the acquisition date fair value of the Company’s previously held equity interest in the acquiree (if any), over (b) the fair value of assets acquired and liabilities assumed. Goodwill and intangible assets, deemed to have indefinite lives, are subject to annual impairment tests as described below. Goodwill and indefinite-lived intangible assets are tested for impairment on at least an annual basis in the fourth quarter of the year. In addition, the Company evaluates its reporting units for impairment if events or circumstances change between annual tests indicating a possible impairment. Examples of such events or circumstances include, but are not limited to, the following: ● ● ● ● ● As part of the Company’s goodwill impairment test, the Company estimates the fair value of each of its reporting units using discounted cash flow analyses. At December 31, 2019, the Company’s reporting units consisted of its five geographic solid waste operating segments and its E&P segment. As of July 1, 2020, the Company combined all operations of its E&P segment into the Southern segment, based on the Company’s determination that the two operating segments met the aggregation criteria, and eliminated the E&P segment. The Company’s former E&P segment had $0 of goodwill at each of December 31, 2020 and December 31, 2019. The Company compares the fair value of each reporting unit with the carrying value of the net assets assigned to each reporting unit. If the fair value of a reporting unit is greater than the carrying value of the net assets, including goodwill, assigned to the reporting unit, then no impairment results. If the fair value is less than its carrying value, an impairment charge is recorded for the amount by which the carrying value exceeds its fair value, not to exceed the carrying amount of goodwill. In testing indefinite-lived intangible assets for impairment, the Company compares the estimated fair value of each indefinite-lived intangible asset to its carrying value. If the fair value of the indefinite-lived intangible asset is less than its carrying value, an impairment charge would be recorded to earnings in the Company’s Consolidated Statements of Net Income. During the Company’s annual impairment analysis of its solid waste operations, the Company determined the fair value of each of its five geographic operating segments at December 31, 2021, 2020 and 2019 and each indefinite-lived intangible asset within those segments using discounted cash flow analyses, which require significant assumptions and estimates about the future operations of each reporting unit and the future discrete cash flows related to each indefinite-lived intangible asset. Significant judgments inherent in these analyses include the determination of appropriate discount rates, the amount and timing of expected future cash flows, growth rates and income tax rates. The cash flows employed in the Company’s 2021 discounted cash flow analyses were based on ten-year financial forecasts, which in turn were based on the 2022 annual budget developed internally by management. These forecasts reflect operating profit margins that were consistent with 2021 results and perpetual revenue growth rates of 4.5%. The Company’s discount rate assumptions are based on an assessment of the market participant rate which approximated 6.1%. In assessing the reasonableness of the Company’s determined fair values of its reporting units, the Company evaluates its results against its current market capitalization. The Company did not record an impairment charge to any of its five geographic operating segments as a result of its annual goodwill impairment tests for the years ended December 31, 2021, 2020 or 2019. During the fourth quarter of 2021, the Company recorded an impairment charge of $2,277, which is included in Impairments and other operating items in the Consolidated Statements of Net Income, on certain indefinite-lived intangible assets at two of its E&P sites in its Southern segment. The Company did not record an impairment charge to any of its five geographic operating segments as a result of its indefinite-lived intangible assets impairment tests for the years ended December 31, 2020 or 2019. Impairments of Property and Equipment and Finite-Lived Intangible Assets Property, equipment and finite-lived intangible assets are carried on the Company’s consolidated financial statements based on their cost less accumulated depreciation or amortization. Finite-lived intangible assets consist of long-term franchise agreements, contracts, customer lists, permits and other agreements. The recoverability of these assets is tested whenever events or changes in circumstances indicate that their carrying amount may not be recoverable. Typical indicators that an asset may be impaired include, but are not limited to, the following: ● ● ● ● ● If any of these or other indicators occur, a test of recoverability is performed by comparing the carrying value of the asset or asset group to its undiscounted expected future cash flows. If the carrying value is in excess of the undiscounted expected future cash flows, impairment is measured by comparing the fair value of the asset to its carrying value. Fair value is determined by an internally developed discounted projected cash flow analysis of the asset. Cash flow projections are sometimes based on a group of assets, rather than a single asset. If cash flows cannot be separately and independently identified for a single asset, the Company will determine whether an impairment has occurred for the group of assets for which the projected cash flows can be identified. If the fair value of an asset is determined to be less than the carrying amount of the asset or asset group, an impairment in the amount of the difference is recorded in the period that the impairment indicator occurs. Several impairment indicators are beyond the Company’s control, and whether or not they will occur cannot be predicted with any certainty. Estimating future cash flows requires significant judgment and projections may vary from cash flows eventually realized. There are other considerations for impairments of landfills, as described below. During the year ended December 31, 2021, the Company recorded a $16,379 impairment charge, which is included in Impairments and other operating items in the Consolidated Statements of Net Income, for property and equipment and definite-lived intangible assets at three of its E&P waste sites in its Southern segment. The demand for the Company’s E&P waste services depends on the continued demand for, and production of, oil and natural gas. Crude oil and natural gas prices historically have been volatile. Macroeconomic and geopolitical conditions, including a significant decline in oil prices occurring in 2020 driven by both surplus production and supply, as well as the decrease in demand caused by factors including the COVID-19 pandemic, resulted in decreased levels of oil and natural gas exploration and production activity and a corresponding decrease in demand for the Company’s E&P waste services in 2020. During the year ended December 31, 2020, total E&P waste revenue declined $112,114, compared to the prior year period, on rig count declines of 56% in certain basins. The most impacted basins include the Williston Basin in North Dakota, the Eagle Ford Basin in Texas and the Powder River Basin in Wyoming, all of which have relatively high costs associated with drilling, making them less attractive than other basins, including the Permian Basin in Texas and New Mexico. Additionally, across the industry there was uncertainty regarding future demand for oil and related services, as noted by several energy companies during 2020, many of whom are customers of the Company’s E&P waste operations. These companies wrote down the values of their oil and gas assets in anticipation of the potential for the decarbonization of their energy product mix given an increased global focus on reducing greenhouse gases and addressing climate change. Such uncertainty regarding global demand had a significant impact on the investment and operating plans of the Company’s E&P waste customers in the basins where the Company operates. The decrease in E&P activity, together with market expectations of a likely slow recovery in oil prices, reduced the expected future period cash flows of the Company’s E&P waste operations. Based on these events, the Company concluded that a triggering event occurred which required the Company to perform an impairment test of the property and equipment and intangible assets of its E&P waste operations as of June 30, 2020 using July 2020 industry projections for drilling activity by basin as the basis for expectations about future activity. Based upon the results of the impairment test, the Company concluded that the carrying value exceeded the projected undiscounted cash flows of four E&P waste landfills. The next step was to calculate the fair value of these four landfills using an income approach employing a discounted cash flow (“DCF”) model over the lesser of 40 years or the remaining life of each landfill. Additional key assumptions used in the DCF mode

Use of Estimates and Assumption

Use of Estimates and Assumptions	12 Months Ended
	Dec. 31, 2021
Use of Estimates and Assumptions [Abstract]
Use of Estimates and Assumptions	4. USE OF ESTIMATES AND ASSUMPTIONS In preparing the Company’s consolidated financial statements, several estimates and assumptions are made that affect the accounting for and recognition of assets, liabilities, revenues and expenses. These estimates and assumptions must be made because certain of the information that is used in the preparation of the Company’s consolidated financial statements is dependent on future events, cannot be calculated with a high degree of precision from data available or is simply not capable of being readily calculated based on generally accepted methodologies. In some cases, these estimates are particularly difficult to determine and the Company must exercise significant judgment. The most difficult, subjective and complex estimates and the assumptions that deal with the greatest amount of uncertainty are related to the Company’s accounting for landfills, self-insurance accruals, income taxes, allocation of acquisition purchase price, contingent consideration accruals and asset impairments, which are discussed in Note 3. An additional area that involves estimation is when the Company estimates the amount of potential exposure it may have with respect to litigation, claims and assessments in accordance with the accounting guidance on contingencies. Actual results for all estimates could differ materially from the estimates and assumptions that the Company uses in the preparation of its consolidated financial statements.

Prepaid Expenses and Other Curr

Prepaid Expenses and Other Current Assets	12 Months Ended
	Dec. 31, 2021
Prepaid Expenses and Other Current Assets [Abstract]
Prepaid Expenses and Other Current Assets	5. PREPAID EXPENSES AND OTHER CURRENT ASSETS Prepaid expenses and other current assets consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2021 2020 Income taxes receivable $ 61,305 $ 50,062 Inventory ​ ​ 44,257 ​ ​ 36,729 Prepaid insurance ​ ​ 22,471 ​ ​ 17,552 Prepaid licenses and permits ​ ​ 10,683 ​ ​ 9,847 Other ​ ​ 37,006 ​ ​ 46,524 ​ $ 175,722 $ 160,714 ​

Property and Equipment, Net

Property and Equipment, Net	12 Months Ended
	Dec. 31, 2021
Property and Equipment, Net [Abstract]
Property and Equipment, Net	6. PROPERTY AND EQUIPMENT, NET Property and equipment, net consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2021 2020 Landfill site costs ​ $ 4,447,530 ​ $ 4,205,968 Rolling stock ​ 2,483,294 ​ 2,227,951 Land, buildings and improvements ​ 1,339,542 ​ 1,147,358 Containers ​ 983,602 ​ 845,386 Machinery and equipment ​ 940,723 ​ 820,533 Construction in progress ​ 82,187 ​ 41,668 ​ ​ 10,276,878 ​ 9,288,864 Less accumulated depreciation and depletion ​ (4,554,929) ​ (4,004,358) ​ ​ $ 5,721,949 ​ $ 5,284,506 ​ Machinery and equipment included $10,342 and $3,754, at December 31, 2021 and 2020, respectively, of equipment assets accounted for as finance leases. The Company’s landfill depletion expense, recorded in Depreciation in the Consolidated Statements of Net Income, for the years ended December 31, 2021, 2020 and 2019, was $212,898, $200,374 and $225,687, respectively.

Intangible Assets, Net

Intangible Assets, Net	12 Months Ended
	Dec. 31, 2021
Intangible Assets, Net [Abstract]
Intangible Assets, Net	9. INTANGIBLE ASSETS, NET Intangible assets, exclusive of goodwill, consisted of the following at December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ ​ Accumulated Net ​ ​ Carrying ​ Accumulated ​ Impairment ​ Carrying ​ ​ Amount ​ Amortization ​ Loss ​ Amount Finite-lived intangible assets: ​ ​ ​ ​ Long-term franchise agreements and contracts ​ $ 724,128 ​ $ (278,827) ​ $ — ​ $ 445,301 Customer lists ​ 711,047 ​ (450,109) ​ — ​ 260,938 Permits and other ​ 538,481 ​ (94,807) ​ — ​ 443,674 ​ ​ 1,973,656 ​ (823,743) ​ — ​ 1,149,913 Indefinite-lived intangible assets: ​ ​ ​ ​ Solid waste collection and transportation permits ​ 181,613 ​ — ​ — ​ 181,613 E&P facility permits ​ 59,855 ​ — ​ (40,784) ​ 19,071 ​ ​ 241,468 ​ — ​ (40,784) ​ 200,684 Intangible assets, exclusive of goodwill ​ $ 2,215,124 ​ $ (823,743) ​ $ (40,784) ​ $ 1,350,597 ​ The weighted-average amortization period of long-term franchise agreements and contracts acquired during the year ended December 31, 2021 was 20.1 years. The weighted-average amortization period of customer lists acquired during the year ended December 31, 2021 was 11.6 years. The weighted-average amortization period of finite-lived permits and other acquired during the year ended December 31, 2021 was 40.0 years. ​ Intangible assets, exclusive of goodwill, consisted of the following at December 31, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ ​ Accumulated Net ​ ​ Carrying ​ Accumulated ​ Impairment ​ Carrying ​ ​ Amount ​ Amortization ​ Loss ​ Amount Finite-lived intangible assets: ​ ​ ​ ​ Long-term franchise agreements and contracts ​ $ 600,674 ​ $ (234,972) ​ $ — ​ $ 365,702 Customer lists ​ 636,035 ​ (382,020) ​ — ​ 254,015 Permits and other ​ 378,952 ​ (79,277) ​ — ​ 299,675 ​ ​ 1,615,661 ​ (696,269) ​ — ​ 919,392 Indefinite-lived intangible assets: ​ ​ ​ ​ ​ ​ Solid waste collection and transportation permits ​ 172,056 ​ — ​ — ​ 172,056 Material recycling facility permits ​ 42,283 ​ — ​ — ​ 42,283 E&P facility permits ​ 59,855 ​ — ​ (38,507) ​ 21,348 ​ ​ 274,194 ​ — ​ (38,507) ​ 235,687 Intangible assets, exclusive of goodwill ​ $ 1,889,855 ​ $ (696,269) ​ $ (38,507) ​ $ 1,155,079 ​ Estimated future amortization expense for the next five years relating to finite-lived intangible assets is as follows: ​ ​ ​ ​ ​ For the year ending December 31, 2022 $ 137,771 For the year ending December 31, 2023 ​ $ 119,458 For the year ending December 31, 2024 ​ $ 103,820 For the year ending December 31, 2025 ​ $ 89,002 For the year ending December 31, 2026 ​ $ 75,122 ​

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2021
Acquisitions [Abstract]
Acquisitions	8. ACQUISITIONS The Company recognizes, separately from goodwill, the identifiable assets acquired and liabilities assumed at their estimated acquisition date fair values. The Company measures and recognizes goodwill as of the acquisition date as the excess of: (a) the aggregate of the fair value of consideration transferred, the fair value of the noncontrolling interest in the acquiree (if any) and the acquisition date fair value of the Company’s previously held equity interest in the acquiree (if any), over (b) the fair value of net assets acquired and liabilities assumed. If information about facts and circumstances existing as of the acquisition date is incomplete by the end of the reporting period in which a business combination occurs, the Company will report provisional amounts for the items for which the accounting is incomplete. The measurement period ends once the Company receives the information it was seeking; however, this period will not exceed one year from the acquisition date. Any material adjustments recognized during the measurement period will be reflected prospectively in the period the adjustment is identified in the consolidated financial statements. The Company recognizes acquisition-related transaction costs as expense. The Company acquired 30 individually immaterial non-hazardous solid waste collection, transfer, recycling and disposal businesses during the year ended December 31, 2021. The purchase consideration recorded during this period for nine of the acquired businesses included contingent consideration based upon the receipt of contract assignments and the achievement of certain targets, including future asset and revenue growth. The fair value of the total contingent consideration recorded during the year ended December 31, 2021 of $31,616 was determined using probability assessments of the expected future cash flows over a one will be charged or credited to expense until the contingency is settled. The total transaction-related expenses incurred during the year ended December 31, 2021 for these acquisitions was $11,318. These expenses are included in Selling, general and administrative expenses in the Company’s Consolidated Statements of Net Income. The Company acquired 21 individually immaterial non-hazardous solid waste collection, transfer, recycling and disposal businesses during the year ended December 31, 2020. The total transaction-related expenses incurred during the year ended December 31, 2020 for these acquisitions were $9,803. These expenses are included in Selling, general and administrative expenses in the Company’s Consolidated Statements of Net Income. The Company acquired 21 individually immaterial non-hazardous solid waste collection, transfer, recycling and disposal businesses during the year ended December 31, 2019. The purchase consideration recorded during this period for five of the acquired businesses included contingent consideration based upon the achievement of certain targets, including future asset and revenue growth. The fair value of the total contingent consideration recorded during the year ended December 31, 2019 of $14,038 was determined using probability assessments of the expected future cash flows over a one The results of operations of the acquired businesses have been included in the Company’s consolidated financial statements from their respective acquisition dates. The Company expects these acquired businesses to contribute towards the achievement of the Company’s strategy to expand through acquisitions. Goodwill acquired is attributable to the synergies and ancillary growth opportunities expected to arise after the Company’s acquisition of these businesses. The following table summarizes the consideration transferred to acquire these businesses and the amounts of identifiable assets acquired and liabilities assumed at the acquisition dates for the acquisitions consummated in the years ended December 31, 2021, 2020 and 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2021 2020 2019 ​ ​ Acquisitions ​ Acquisitions ​ Acquisitions Fair value of consideration transferred: ​ ​ ​ Cash ​ $ 960,449 ​ $ 388,789 ​ $ 736,610 Debt assumed ​ 108,345 ​ 91,349 ​ 95,809 Change in open working capital settlements at year end ​ ​ — ​ ​ 1,505 ​ ​ 5,272 ​ ​ 1,068,794 ​ 481,643 ​ 837,691 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired: ​ ​ ​ Accounts receivable ​ 33,236 ​ 13,759 ​ 25,220 Prepaid expenses and other current assets ​ 4,866 ​ 4,509 ​ 4,970 Operating lease right-of-use assets ​ ​ 5,972 ​ ​ 5,247 ​ ​ 3,616 Property and equipment ​ 394,687 ​ 173,394 ​ 294,037 Long-term franchise agreements and contracts ​ 134,827 ​ 59,149 ​ 78,312 Indefinite-lived intangibles ​ 9,557 ​ 13,465 ​ — Customer lists ​ 75,612 ​ 48,512 ​ 52,422 Permits and other intangibles ​ ​ 116,967 ​ ​ 10,507 ​ ​ 48,141 Other assets ​ 77 ​ 389 ​ 7 Accounts payable and accrued liabilities ​ (37,827) ​ (14,174) ​ (19,209) Current portion of operating lease liabilities ​ ​ (1,370) ​ ​ (509) ​ ​ (658) Deferred revenue ​ (8,389) ​ (1,821) ​ (17,245) Contingent consideration ​ (31,616) ​ (4,688) ​ (14,038) Long-term portion of operating lease liabilities ​ ​ (4,602) ​ ​ (4,738) ​ ​ (2,958) Other long-term liabilities ​ (13,976) ​ (2,136) ​ (8,707) Deferred income taxes ​ (63,822) ​ (4,525) ​ (13,287) Total identifiable net assets ​ 614,199 ​ 296,340 ​ 430,623 Goodwill ​ $ 454,595 ​ $ 185,303 ​ $ 407,068 ​ Goodwill acquired in 2021 totaling $187,287 is expected to be deductible for tax purposes. Goodwill acquired in 2020 totaling $169,147 is expected to be deductible for tax purposes. Goodwill acquired in 2019 totaling $266,310 is expected to be deductible for tax purposes. The fair value of acquired working capital related to 19 individually immaterial acquisitions completed during the year ended December 31, 2021, is provisional pending receipt of information from the acquirees to support the fair value of the assets acquired and liabilities assumed. Any adjustments recorded relating to finalizing the working capital for these 19 acquisitions are not expected to be material to the Company’s financial position. The gross amount of trade receivables due under contracts acquired during the year ended December 31, 2021, was $36,645, of which $3,409 was expected to be uncollectible. The gross amount of trade receivables due under contracts acquired during the year ended December 31, 2020, was $13,854, of which $95 was expected to be uncollectible. The gross amount of trade receivables due under contracts acquired during the year ended December 31, 2019, was $27,297, of which $2,077 was expected to be uncollectible. The Company did not acquire any other class of receivable as a result of the acquisition of these businesses.

Leases

Leases	12 Months Ended
	Dec. 31, 2021
Lessee Disclosure [Abstract]
Leases	7. LEASES The Company rents certain equipment and facilities under short-term agreements, non-cancelable operating lease agreements and finance leases. The Company determines if an arrangement is or contains a lease at contract inception. The Company recognizes a right-of-use (“ROU”) asset and a lease liability at the lease commencement date. The lease liability is initially measured at the present value of the unpaid lease payments at the lease commencement date. Key estimates and judgments include how the Company determines (1) the discount rate it uses to discount the unpaid lease payments to present value, (2) lease term and (3) lease payments. The lease guidance requires a lessee to discount its unpaid lease payments using the interest rate implicit in the lease or, if that rate cannot be readily determined, its incremental borrowing rate. Generally, the Company cannot determine the interest rate implicit in the lease because it does not have access to the lessor’s estimated residual value or the amount of the lessor’s deferred initial direct costs. Therefore, the Company generally uses its incremental borrowing rate as the discount rate for the lease. The Company’s incremental borrowing rate for a lease is the rate of interest it would have to pay on a collateralized basis to borrow an amount equal to the lease payments under similar terms. The lease term for the Company’s leases includes the noncancelable period of the lease, plus any additional periods covered by either a Company option to extend (or not to terminate) the lease that the Company is reasonably certain to exercise, or an option to extend (or not to terminate) the lease controlled by the lessor. Lease payments included in the measurement of the lease liability comprise fixed payments or variable lease payments. The variable lease payments take into account annual changes in the consumer price index and common area maintenance charges, if known. ROU assets for operating and finance leases are periodically reviewed for impairment losses. The Company uses the long-lived asset impairment guidance in ASC Subtopic 360-10, Property, Plant, and Equipment – Overall, to determine whether an ROU asset is impaired, and if so, the amount of the impairment loss to recognize. The Company did not recognize an impairment charge for any of its ROU assets during the years ended December 31, 2021, 2020 and 2019. The Company monitors for events or changes in circumstances that require a reassessment of one of its leases. When a reassessment results in the remeasurement of a lease liability, a corresponding adjustment is made to the carrying amount of the corresponding ROU asset. The Company did not recognize any significant remeasurements during the years ended December 31, 2021, 2020 and 2019. The Company has elected not to recognize ROU assets and lease liabilities for short-term leases that have a lease term of 12 months or less. The Company has elected to apply the short-term lease recognition and measurement exemption allowed for in the lease accounting standard. The Company recognizes the lease payments associated with its short-term leases as an expense on a straight-line basis over the lease term. The Company initially entered into finance leases in December 2020 and the assets under these leases went into service on December 31, 2020. Lease cost for operating and finance leases for the years ended December 31, 2021, 2020 and 2019 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2021 ​ 2020 ​ 2019 Operating lease cost ​ $ 40,381 ​ $ 39,411 ​ $ 38,710 Finance lease cost: ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortization of leased assets ​ ​ 3,424 ​ ​ — ​ ​ — Interest on leased liabilities ​ ​ 152 ​ ​ — ​ ​ — Total lease cost ​ $ 43,957 ​ $ 39,411 ​ $ 38,710 ​ Supplemental cash flow information and non-cash activity related to the Company’s leases are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2021 ​ ​ 2020 ​ ​ 2019 Cash paid for amounts included in the measurement of lease liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating cash flows from operating leases ​ $ 40,249 ​ $ 39,212 ​ $ 38,226 Operating cash flows from finance leases ​ $ 152 ​ $ — ​ $ — Financing cash flows from finance leases ​ $ 3,133 ​ $ — ​ $ — Non-cash activity: ​ ​ ​ ​ ​ ​ ​ ​ ​ Right-of-use assets obtained in exchange for lease liabilities - operating leases ​ $ 17,933 ​ $ 15,117 ​ $ 17,774 Right-of-use assets obtained in exchange for lease liabilities - finance leases ​ $ 10,012 ​ $ 3,754 ​ $ — ​ Weighted-average remaining lease term and discount rate for the Company’s leases are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 ​ 2020 ​ 2019 Weighted average remaining lease term - operating leases ​ 8.0 years 8.6 years 8.7 years Weighted average remaining lease term - finance leases ​ 4.9 years ​ 5.4 years ​ Not applicable ​ Weighted average discount rate - operating leases ​ 3.37 % 3.86 % 3.99 % Weighted average discount rate - finance leases ​ 1.89 % ​ 1.89 % ​ Not applicable ​ ​ As of December 31, 2021, future minimum lease payments, reconciled to the respective lease liabilities, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating Leases ​ ​ Finance Leases 2022 $ 38,956 ​ $ 2,162 2023 ​ 34,060 ​ 2,162 2024 ​ 26,066 ​ 2,162 2025 ​ 19,310 ​ 2,162 2026 ​ 14,455 ​ 2,161 Thereafter ​ 62,747 ​ 234 Minimum lease payments ​ 195,594 ​ 11,043 Less: imputed interest ​ (27,949) ​ (524) Present value of minimum lease payments ​ ​ 167,645 ​ ​ 10,519 Less: current portion of lease liabilities ​ ​ (38,017) ​ ​ (2,061) Long-term portion of lease liabilities ​ $ 129,628 ​ $ 8,458 ​

Accrued Liabilities

Accrued Liabilities	12 Months Ended
	Dec. 31, 2021
Accrued Liabilities [Abstract]
Accrued Liabilities	10. ACCRUED LIABILITIES Accrued liabilities consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2021 2020 Insurance claims and premiums ​ $ 149,864 ​ $ 147,188 Payroll and payroll-related ​ 141,877 ​ 141,371 Interest payable ​ 28,729 ​ 29,580 Final capping, closure and post-closure liability ​ ​ 19,925 ​ ​ 19,925 Unrealized cash flow hedge losses ​ 18,675 ​ 20,023 Property taxes ​ ​ 8,833 ​ ​ 6,381 Cell processing reserve ​ 3,364 ​ 3,344 Transaction-related expenses ​ ​ 3,130 ​ ​ 3,304 Share-based compensation plan liability ​ 2,423 ​ 868 Environmental remediation reserve ​ 2,300 ​ 2,300 Other ​ 63,476 ​ 30,639 ​ ​ $ 442,596 ​ $ 404,923 ​

Long-Term Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2021
Long-Term Debt [Abstract]
Long-Term Debt	11. LONG-TERM DEBT The following table presents the Company’s long-term debt as of December 31, 2021 and 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2021 2020 Revolver under Credit Agreement, bearing interest ranging from 1.10% to 3.25% (a) ​ $ 803,944 ​ $ 203,927 Term loan under Credit Agreement, bearing interest at 1.10% (a) ​ 650,000 ​ ​ 650,000 4.64% Senior Notes due 2021 ​ — ​ ​ 100,000 2.39% Senior Notes due 2021 ​ — ​ ​ 150,000 3.09% Senior Notes due 2022 ​ — ​ ​ 125,000 2.75% Senior Notes due 2023 ​ — ​ ​ 200,000 3.24% Senior Notes due 2024 ​ — ​ ​ 150,000 3.41% Senior Notes due 2025 ​ — ​ ​ 375,000 3.03% Senior Notes due 2026 ​ — ​ ​ 400,000 3.49% Senior Notes due 2027 ​ — ​ ​ 250,000 4.25% Senior Notes due 2028 ​ ​ 500,000 ​ ​ 500,000 3.50% Senior Notes due 2029 ​ ​ 500,000 ​ ​ 500,000 2.60% Senior Notes due 2030 ​ ​ 600,000 ​ ​ 600,000 2.20% Senior Notes due 2032 ​ ​ 650,000 ​ ​ — 3.05% Senior Notes due 2050 ​ ​ 500,000 ​ ​ 500,000 2.95% Senior Notes due 2052 ​ ​ 850,000 ​ ​ — Notes payable to sellers and other third parties, bearing interest ranging from 2.42% to 10.35%, principal and interest payments due periodically with due dates ranging from 2028 to 2036 (a) ​ 37,508 ​ ​ 43,131 Finance leases, bearing interest at 1.89% with a lease expiration date of 2027 (a) ​ ​ 10,519 ​ ​ 3,754 ​ ​ 5,101,971 ​ 4,750,812 Less – current portion ​ (6,020) ​ ​ (8,268) Less – unamortized debt discount and issuance costs ​ (55,451) ​ ​ (33,866) ​ ​ $ 5,040,500 ​ $ 4,708,678 (a) Interest rates represent the interest rates incurred at December 31, 2021. Credit Agreement The Company has a revolving credit and term loan agreement (as amended, restated, amended and restated, supplemented or otherwise modified from time to time, the “Credit Agreement”) with Bank of America, N.A., acting through its Canada Branch, as the global agent, the swing line lender and a letter of credit issuer, Bank of America, N.A., as the U.S. agent and a letter of credit issuer, the other lenders named therein (the “Lenders”) and any other financial institutions from time to time party thereto. There are no subsidiary guarantors under the Credit Agreement. The Credit Agreement has a scheduled maturity date of July 30, 2026, which may be extended further upon agreement by Lenders holding at least 50% of the commitments and credit extensions outstanding, with respect to their respective commitments and credit extensions outstanding. Any Lender that does not agree to an extension of the maturity date shall not be so extended with respect to their commitments and credit extensions. Details of the Credit Agreement are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2021 2020 Revolver under Credit Agreement ​ ​ ​ Available $ 933,775 ​ $ 1,238,937 ​ Letters of credit outstanding $ 112,281 ​ $ 119,636 ​ Total amount drawn, as follows: $ 803,944 ​ $ 203,927 ​ Amount drawn - U.S. LIBOR rate loan $ 631,000 ​ $ 200,000 ​ Interest rate applicable - U.S. LIBOR rate loan ​ 1.10 % ​ 1.35 % Interest rate margin - U.S. LIBOR rate loan ​ 1.00 % ​ 1.20 % Amount drawn - U.S. base rate loan $ 158,000 ​ $ — ​ Interest rate applicable - U.S. base rate loan ​ 3.25 % ​ — % Interest rate margin - U.S. base rate loan ​ 0.00 % ​ — % Amount drawn - U.S. swingline loan $ 11,000 ​ $ — ​ Interest rate applicable - U.S. swingline loan ​ 3.25 % ​ — % Interest rate margin - U.S. swingline loan ​ 0.00 % ​ — % Amount drawn – Canadian bankers’ acceptance $ 3,944 ​ $ 3,927 ​ Interest rate applicable – Canadian bankers’ acceptance 1.45 % 1.66 % Interest rate acceptance fee – Canadian bankers’ acceptance 1.00 % 1.20 % Commitment – rate applicable 0.09 % 0.15 % Term loan under Credit Agreement ​ ​ ​ ​ Amount drawn – U.S. based LIBOR loan $ 650,000 ​ $ 650,000 ​ Interest rate applicable – U.S. based LIBOR loan 1.10 % 1.35 % Interest rate margin – U.S. based LIBOR loan 1.00 % 1.20 % ​ In addition to the $112,281 of letters of credit at December 31, 2021 issued and outstanding under the Credit Agreement, the Company has issued and outstanding letters of credit totaling $13,527 under facilities other than the Credit Agreement. Pursuant to the terms and conditions of the Credit Agreement, the Lenders provide a $2,500,000 credit facility to the Company, consisting of (i) revolving advances up to an aggregate principal amount of $1,850,000 at any one time outstanding, and (ii) a term loan in an aggregate principal amount of $650,000. As part of the aggregate commitments under the revolving advances, the Credit Agreement provides for letters of credit to be issued at the request of the Company in an aggregate amount not to exceed $320,000 and for swing line loans to be issued at the request of the Company in an aggregate amount not to exceed the lessor of $100,000 and the aggregate commitments under the revolving advances. Both the letter of credit sublimit and the swing line sublimit are part of, and not in addition to, the aggregate commitments under the revolving advances. Subject to certain specified conditions and additional deliveries, the Company has the option to request increases in the aggregate commitments for revolving advances and one or more additional term loans, provided that (i) the aggregate principal amount of such requests does not exceed $500,000 and (ii) the aggregate principal amount of commitments and term loans under the credit facility does not exceed $3,000,000. As of December 31, 2021, there are no commitments by lenders for any such increases in aggregate principal amount of revolving advances or additional term loans described in the preceding sentence. The Company has $3,711 of debt issuance costs related to the Credit Agreement recorded in Other assets, net in the Consolidated Balance Sheets at December 31, 2021, which are being amortized through the maturity date, or July 30, 2026. Advances are available under the Credit Agreement in U.S. dollars and Canadian dollars. Interest accrues on the term loan at a LIBOR rate or a base rate, at the Company’s option, plus an applicable margin. Interest accrues on revolving advances, at the Company’s option, (i) at a LIBOR rate or a base rate for U.S. dollar borrowings, plus an applicable margin, and (ii) at the Canadian prime rate for Canadian dollar borrowings, plus an applicable margin. Canadian dollar borrowings are also available by way of bankers’ acceptances or BA equivalent notes, subject to the payment of a drawing fee. Certain fees for letters of credit in US dollars and Canadian dollars are also based on the applicable margin. The applicable margin used in connection with interest rates and fees is based on the debt rating of the Company’s public non-credit-enhanced, senior unsecured long-term debt (the “Debt Rating”). The applicable margin for LIBOR rate loans, drawing fees for bankers’ acceptances, BA equivalent notes and certain letter of credit fees ranges from 0.750% to 1.250%, and the applicable margin for U.S. base rate loans, Canadian prime rate loans and swing line loans ranges from 0.00% to 0.250%. The Company will also pay a fee based on the Debt Rating on the actual daily unused amount of the aggregate revolving commitments, ranging from 0.065% to 0.150%.‎ The Credit Agreement contains hardwired mechanics for the replacement of LIBOR, including (1) mechanics to transition to a rate based upon the secured overnight financing rate (“SOFR”) published by the Federal Reserve Bank of New York or a successor administrator on its website (or a successor source) upon the earlier of (x) LIBOR’s cessation or loss of representativeness, (y) June 30, 2023 and (z) the effectiveness of an early opt-in election by the Company and the agents subject to certain terms and (2) mechanics to transition to an alternate benchmark rate giving due consideration to any evolving or then-prevailing market conventions for U.S. dollar-denominated syndicated credit facilities at such time upon the occurrence of certain subsequent transition events, the unavailability of SOFR-based alternatives or the effectiveness of an early opt-in election by the Company and the agents subject to certain terms. The borrowings under the Credit Agreement are unsecured and there are no subsidiary guarantors under the Credit Agreement. Proceeds from borrowings under the Credit Agreement may be used (i) to finance acquisitions, dividends or other equity distributions permitted under the Credit Agreement and (ii) for capital expenditures, working capital, payment of certain transaction fees and expenses, letters of credit and any other lawful corporate purposes. The Credit Agreement contains customary representations, warranties, covenants and events of default, including, among others, a change of control event of default and limitations on the incurrence of indebtedness and liens, new lines of business, mergers, transactions with affiliates and burdensome agreements. During the continuance of an event of default, the Lenders may take a number of actions, including, among others, declaring the entire amount then outstanding under the Credit Agreement to be due and payable. The Credit Agreement includes a financial covenant limiting, as of the last day of each fiscal quarter, the ratio of (a) Consolidated Total Funded Debt (as defined in the Credit Agreement) as of such date to (b) Consolidated EBITDA (as defined in the Credit Agreement), measured for the preceding 12 months, to not more than 3.75 to 1.00 (or 4.25 to 1.00 during material acquisition periods, subject to certain limitations). As of December 31, 2021 and 2020, the Company was in compliance with all applicable covenants in the Credit Agreement as in effect as of the applicable date. Private Placement Notes Pursuant to the terms and conditions of a Master Note Purchase Agreement dated as of June 1, 2016 (as amended, restated, amended and restated, supplemented or otherwise modified from time to time, the “2016 NPA”) between the Company and certain accredited institutional investors, the Company issued senior unsecured notes (the “2016 Private Placement Notes”) consisting of (i) $150,000 of senior notes due June 1, 2021 (the “June 2021 Private Placement Notes”), (ii) $200,000 of senior notes due June 1, 2023, (iii) $150,000 of senior notes due April 20, 2024, (iv) $400,000 of senior notes due June 1, 2026 and (v) $250,000 of senior notes due April 20, 2027. Pursuant to the terms and conditions of a Master Note Purchase Agreement, dated as of July 15, 2008 (as amended, restated, amended and restated, assumed, supplemented or otherwise modified from time to time, the “2008 NPA”) between the Company and certain accredited institutional investors, the Company issued senior unsecured notes (the “2008 Private Placement Notes” and together with the 2016 Private Placement Notes, the “Private Placement Notes”) consisting of (i) $100,000 of senior notes due April 1, 2021 (the “April 2021 Private Placement Notes” and together with the June 2021 Private Placement Notes, the “2021 Private Placement Notes”), (ii) $125,000 of senior notes due August 20, 2022 and (iii) $375,000 of senior notes due August 20, 2025. The Company repaid at maturity the 2021 Private Placement Notes and repaid the other Private Placement Notes in connection with the Offering (defined below) in September 2021. Senior Notes On November 16, 2018, the Company completed an underwritten public offering of $500,000 aggregate principal amount of its 4.25% Senior Notes due December 1, 2028 (the “2028 Senior Notes”). The 2028 Senior Notes were issued under the Indenture, dated as of November 16, 2018 (as amended, restated, amended and restated, supplemented or otherwise modified from time to time, the “Indenture”), by and between the Company and U.S. Bank National Association, as trustee (the “Trustee”), as supplemented through the First Supplemental Indenture, dated as of November 16, 2018. The Company is amortizing the $5,792 of debt issuance costs through the maturity date of the 2028 Senior Notes. The Company may redeem some or all of the 2028 Senior Notes at its option prior to September 1, 2028 (three months before the maturity date) at any time and from time to time at a redemption price equal to the greater of 100% of the principal amount of the 2028 Senior Notes redeemed, or the sum of the present values of the remaining scheduled payments of principal and interest on the 2028 Senior Notes redeemed, plus accrued and unpaid interest to, but excluding, the redemption date. Commencing on September 1, 2028 (three months before the maturity date), the Company may redeem some or all of the 2028 Senior Notes, at any time and from time to time, at a redemption price equal to the principal amount of the 2028 Senior Notes being redeemed plus accrued and unpaid interest to, but excluding, the redemption date. On April 16, 2019, the Company completed an underwritten public offering of $500,000 aggregate principal amount of its 3.50% Senior Notes due May 1, 2029 (the “2029 Senior Notes”). The 2029 Senior Notes were issued under the Indenture, as supplemented through the Second Supplemental Indenture, dated as of April 16, 2019. The Company is amortizing the $5,954 of debt issuance costs through the maturity date of the 2029 Senior Notes. The Company may redeem some or all of the 2029 Senior Notes at its option prior to February 1, 2029 (three months before the maturity date) at any time and from time to time at a redemption price equal to the greater of 100% of the principal amount of the 2029 Senior Notes redeemed, or the sum of the present values of the remaining scheduled payments of principal and interest on the 2029 Senior Notes redeemed, plus accrued and unpaid interest to, but excluding, the redemption date. Commencing on February 1, 2029 (three months before the maturity date), the Company may redeem some or all of the 2029 Senior Notes, at any time and from time to time, at a redemption price equal to the principal amount of the 2029 Senior Notes being redeemed plus accrued and unpaid interest to, but excluding, the redemption date. On January 23, 2020, the Company completed an underwritten public offering of $600,000 aggregate principal amount of 2.60% Senior Notes due February 1, 2030 (the “2030 Senior Notes”). The 2030 Senior Notes were issued under the Indenture, as supplemented through the Third Supplemental Indenture, dated as of January 23, 2020. The Company is amortizing $5,435 of debt issuance costs through the maturity date of the 2030 Senior Notes. The Company may redeem some or all of the 2030 Senior Notes at its option prior to November 1, 2029 (three months before the maturity date) at any time and from time to time at a redemption price equal to the greater of 100% of the principal amount of the 2030 Senior Notes redeemed, or the sum of the present values of the remaining scheduled payments of principal and interest on the 2030 Senior Notes redeemed, plus accrued and unpaid interest to, but excluding, the redemption date. Commencing on November 1, 2029 (three months before the maturity date), the Company may redeem some or all of the 2030 Senior Notes, at any time and from time to time, at a redemption price equal to the principal amount of the 2030 Senior Notes being redeemed plus accrued and unpaid interest to, but excluding, the redemption date. On March 13, 2020, the Company completed an underwritten public offering of $500,000 aggregate principal amount of 3.05% Senior Notes due April 1, 2050 (the “2050 Senior Notes”). The 2050 Senior Notes were issued under the Indenture, as supplemented through the Fourth Supplemental Indenture, dated as of March 13, 2020. The Company is amortizing a $7,375 debt discount and $5,682 of debt issuance costs through the maturity date of the 2050 Senior Notes. The Company may redeem some or all of the 2050 Senior Notes at its option prior to October 1, 2049 (six months before the maturity date) at any time and from time to time at a redemption price equal to the greater of 100% of the principal amount of the 2050 Senior Notes redeemed, or the sum of the present values of the remaining scheduled payments of principal and interest on the 2050 Senior Notes redeemed, plus accrued and unpaid interest to, but excluding, the redemption date. Commencing on October 1, 2049 (six months before the maturity date), the Company may redeem some or all of the 2050 Senior Notes, at any time and from time to time, at a redemption price equal to the principal amount of the 2050 Senior Notes being redeemed plus accrued and unpaid interest to, but excluding, the redemption date. On September 20, 2021, the Company completed an underwritten public offering (the “Offering”) of $650,000 aggregate principal amount of 2.20% Senior Notes due January 15, 2032 (the “2032 Senior Notes”) and $850,000 aggregate principal amount of 2.95% Senior Notes due January 15, 2052 (the “2052 Senior Notes” and, together with the 2028 Senior Notes, the 2029 Senior Notes, the 2030 Senior Notes, the 2032 Senior Notes and the 2050 Senior Notes, the “Senior Notes”). The 2032 Senior Notes and the 2052 Senior Notes were issued under the Indenture, as supplemented through the Fifth Supplemental Indenture, dated as of September 20, 2021. The Company is amortizing a $1,066 debt discount and $5,979 of debt issuance costs through the maturity date of the 2032 Senior Notes and a $12,742 debt discount and $9,732 of debt issuance costs through the maturity date of the 2052 Senior Notes. The Company may, prior to October 15, 2031 (three months before the maturity date), redeem some or all of the 2032 Senior Notes, at any time and from time to time, at a redemption price equal to the greater of 100% of the principal amount of the 2032 Senior Notes redeemed, or the sum of the present values of the remaining scheduled payments of principal and interest on the 2032 Senior Notes redeemed. Commencing on October 15, 2031 (three months before the maturity date), the Company may redeem some or all of the 2032 Senior Notes, at any time and from time to time, at a redemption price equal to the principal amount of the 2032 Senior Notes being redeemed plus accrued and unpaid interest to, but excluding, the redemption date. The Company may, prior to July 15, 2051 (six months before the maturity date), redeem some or all of the 2052 Senior Notes, at any time and from time to time, at a redemption price equal to the greater of 100% of the principal amount of the 2052 Senior Notes redeemed, or the sum of the present values of the remaining scheduled payments of principal and interest on the 2052 Senior Notes redeemed. Commencing on July 15, 2051 (six months before the maturity date), the Company may redeem some or all of the 2052 Senior Notes, at any time and from time to time, at a redemption price equal to the principal amount of the 2052 Senior Notes being redeemed plus accrued and unpaid interest to, but excluding, the redemption date. In connection with the Offering, the Company exercised its right to repay the $1,500,000 of Private Placement Notes then outstanding governed by the 2008 NPA and the 2016 NPA. The Company repaid the Private Placement Notes then outstanding, including the $110,617 make-whole premium, with the net proceeds from the Offering and borrowings under the revolving credit facility provided under its Credit Agreement. The Company recorded $115,288 to Loss on early extinguishment of debt during the year ended December 31, 2021 due to the repayment of the Private Placement Notes and associated make-whole premium and related fees. The Company pays interest on the Senior Notes semi-annually in arrears. The Senior Notes are the Company’s senior unsecured obligations, ranking equally in right of payment with its existing and future unsubordinated debt and senior to any of its future subordinated debt. The Senior Notes are not guaranteed by any of the Company’s subsidiaries. Under certain circumstances, the Company may become obligated to pay additional amounts (the “Additional Amounts”) with respect to the Senior Notes to ensure that the net amounts received by each holder of the Senior Notes will not be less than the amount such holder would have received if withholding taxes or deductions were not incurred on a payment under or with respect to the Senior Notes. If such payment of Additional Amounts is a result of a change in the laws or regulations, including a change in any official position, the introduction of an official position or a holding by a court of competent jurisdiction, of any jurisdiction from or through which payment is made by or on behalf of the Senior Notes having power to tax, and the Company cannot avoid such payments of Additional Amounts through reasonable measures, then the Company may redeem the applicable series of the Senior Notes then outstanding at a redemption price equal to 100% of the principal amount thereof, plus accrued and unpaid interest, if any, to, but excluding, the redemption date (subject to the right of holders of record on the relevant record date to receive interest due on an interest payment date that is on or prior to the redemption date). If the Company experiences certain kinds of changes of control, each holder of the Senior Notes may require the Company to repurchase all or a portion of the Senior Notes for cash at a price equal to 101% of the aggregate principal amount of such Senior Notes, plus any accrued but unpaid interest to, but excluding, the date of repurchase. The covenants in the Indenture include limitations on liens, sale-leaseback transactions and mergers and sales of all or substantially all of the Company’s assets. The Indenture also includes customary events of default with respect to the Senior Notes. As of December 31, 2021 and 2020, the Company was in compliance with all applicable covenants in the Indenture as in effect on the applicable date. Upon an event of default, the principal of and accrued and unpaid interest on all the Senior Notes may be declared to be due and payable by the Trustee or the holders of not less than 25% in principal amount of the outstanding Senior Notes of the applicable series. Upon such a declaration, such principal and accrued interest on all of the applicable series of the Senior Notes will be due and payable immediately. In the case of an event of default resulting from certain events of bankruptcy, insolvency or reorganization, the principal (or such specified amount) of and accrued and unpaid interest, if any, on all outstanding series of the Senior Notes will become and be immediately due and payable without any declaration or other act on the part of the Trustee or any holder of the applicable series of the Senior Notes. Under certain As of December 31, 2021, aggregate contractual future principal payments by calendar year on long-term debt are due as follows: ​ ​ ​ ​ ​ 2022 $ 6,020 2023 ​ 6,090 2024 ​ 6,239 2025 ​ 6,391 2026 ​ 1,460,243 Thereafter ​ 3,616,988 ​ ​ $ 5,101,971 ​

Fair Value of Financial Instrum

Fair Value of Financial Instruments	12 Months Ended
	Dec. 31, 2021
Fair Value of Financial Instruments [Abstract]
Fair Value of Financial Instruments	12. FAIR VALUE OF FINANCIAL INSTRUMENTS The Company uses a three-tier fair value hierarchy to classify and disclose all assets and liabilities measured at fair value on a recurring basis in periods subsequent to their initial measurement. These tiers include: Level 1, defined as quoted market prices in active markets for identical assets or liabilities; Level 2, defined as inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, model-based valuation techniques for which all significant assumptions are observable in the market, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities; and Level 3, defined as unobservable inputs that are not corroborated by market data. The Company’s financial assets and liabilities recorded at fair value on a recurring basis include derivative instruments and restricted cash and investments. At December 31, 2021 and 2020, the Company’s derivative instruments included pay-fixed, receive-variable interest rate swaps. The Company’s interest rate swaps are recorded at their estimated fair values based on quotes received from financial institutions that trade these contracts. The Company verifies the reasonableness of these quotes using similar quotes from another financial institution as of each date for which financial statements are prepared. For the Company’s interest rate swaps, the Company also considers the Company’s creditworthiness in its determination of the fair value measurement of these instruments in a net liability position and the counterparties’ creditworthiness in its determination of the fair value measurement of these instruments in a net asset position. The Company’s restricted cash is valued at quoted market prices in active markets for identical assets, which the Company receives from the financial institutions that hold such investments on its behalf. The Company’s restricted cash measured at fair value is invested primarily in money market accounts, bank time deposits and U.S. government and agency securities. The Company’s restricted investments are valued at quoted market prices in active markets for similar assets, which the Company receives from the financial institutions that hold such investments on its behalf. The Company’s restricted investments measured at fair value are invested primarily in money market accounts, bank time deposits, U.S. government and agency securities and Canadian bankers’ acceptance notes. The Company’s assets and liabilities measured at fair value on a recurring basis at December 31, 2021 and 2020, were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurement at December 31, 2021 Using ​ ​ ​ Quoted Prices in Significant ​ ​ ​ ​ ​ ​ ​ Active Markets ​ Other ​ Significant ​ ​ ​ ​ ​ for Identical ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Assets ​ Inputs ​ Inputs ​ ​ Total ​ (Level 1) ​ (Level 2) ​ (Level 3) Interest rate swap derivative instruments – net liability position ​ $ (51,081) ​ $ — ​ $ (51,081) ​ $ — Restricted cash ​ $ 72,174 ​ $ 72,174 ​ $ — ​ $ — Restricted investments ​ $ 58,797 ​ $ — ​ $ 58,797 ​ $ — Contingent consideration ​ $ (94,308) ​ $ — ​ $ — ​ $ (94,308) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurement at December 31, 2020 Using ​ ​ ​ Quoted Prices in Significant ​ ​ ​ ​ ​ ​ ​ Active Markets ​ Other ​ Significant ​ ​ ​ ​ ​ for Identical ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Assets ​ Inputs ​ Inputs ​ ​ Total ​ (Level 1) ​ (Level 2) ​ (Level 3) Interest rate swap derivative instruments – net liability position ​ $ (94,689) ​ $ — ​ $ (94,689) ​ $ — Restricted cash ​ $ 97,095 ​ $ 97,095 ​ $ — ​ $ — Restricted investments ​ $ 58,181 ​ $ — ​ $ 58,181 ​ $ — Contingent consideration ​ $ (71,736) ​ $ — ​ $ — ​ $ (71,736) ​ See Note 3 – “Impairments of Property and Equipment and Finite-Lived Intangible Assets” regarding non-recurring fair value measurements. ​ The following table summarizes the changes in the fair value for Level 3 liabilities related to contingent consideration for the years ended December 31, 2021 and 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 2020 Beginning balance ​ $ 71,736 ​ $ 69,484 Contingent consideration recorded at acquisition date ​ 31,616 ​ 4,688 Payment of contingent consideration recorded at acquisition date ​ (12,934) ​ (12,566) Payment of contingent consideration recorded in earnings ​ (520) ​ (10,371) Adjustments to contingent consideration ​ ​ 2,954 ​ ​ 18,418 Interest accretion expense ​ 1,470 ​ 2,006 Foreign currency translation adjustment ​ (14) ​ 77 Ending balance ​ $ 94,308 ​ $ 71,736 ​

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2021
Commitments and Contingencies [Abstract]
Commitments and Contingencies	13. COMMITMENTS AND CONTINGENCIES COMMITMENTS Financial Surety Bonds The Company uses financial surety bonds for a variety of corporate guarantees. The two largest uses of financial surety bonds are for municipal contract performance guarantees and asset closure and retirement requirements under certain environmental regulations. Environmental regulations require demonstrated financial assurance to meet final capping, closure and post-closure requirements for landfills. In addition to surety bonds, these requirements may also be met through alternative financial assurance instruments, including insurance, letters of credit and restricted cash and investment deposits. At December 31, 2021 and 2020, the Company had provided customers and various regulatory authorities with surety bonds in the aggregate amounts of approximately $744,037 and $727,361, respectively, to secure its asset closure and retirement requirements and $556,570 and $482,262, respectively, to secure performance under collection contracts and landfill operating agreements. The Company owns a 9.9% interest in a company that, among other activities, issues financial surety bonds to secure landfill final capping, closure and post-closure obligations for companies operating in the solid waste industry. The Company accounts for this investment under the cost method of accounting. There have been no identified events or changes in circumstances that may have a significant adverse effect on the carrying value of the investment. This investee company and the parent company of the investee have written financial surety bonds for the Company, of which $410,378 and $413,970 were outstanding as of December 31, 2021 and 2020, respectively. The Company’s reimbursement obligations under these bonds are secured by a pledge of its stock in the investee company. Unconditional Purchase Obligations At December 31, 2021, the Company’s unconditional purchase obligations consist of multiple fixed-price fuel purchase contracts under which it has 60.0 million gallons remaining to be purchased for a total of $151,733. These fuel purchase contracts expire on or before December 31, 2024. During the years ended December 31, 2021, 2020 and 2019, the Company paid $100,220, $93,813 and $73,269, respectively, under the respective fuel purchase contracts then outstanding. As of December 31, 2021, future minimum purchase commitments, by calendar year, are as follows: ​ ​ ​ ​ ​ 2022 $ 98,655 2023 ​ 51,289 2024 ​ ​ 1,789 ​ ​ $ 151,733 ​ CONTINGENCIES Environmental Risks The Company expenses costs incurred to investigate and remediate environmental issues unless they extend the economic useful lives of the related assets. The Company records liabilities when it is probable that an obligation has been incurred and the amounts can be reasonably estimated. The remediation reserves cover anticipated costs, including remediation of environmental damage that waste facilities may have caused to neighboring landowners or residents as a result of contamination of soil, groundwater or surface water, including damage resulting from conditions existing prior to the Company’s acquisition of such facilities. The Company’s estimates are based primarily on investigations and remediation plans established by independent consultants, regulatory agencies and potentially responsible third parties. The Company does not discount remediation obligations. At December 31, 2021 and 2020, the current portion of remediation reserves was $2,300 and $2,300, respectively, which is included in Accrued liabilities in the Consolidated Balance Sheets. At December 31, 2021 and 2020, the long-term portion of remediation reserves was $20,483 and $19,121, respectively, which is included in Other long-term liabilities in the Consolidated Balance Sheets. Any substantial increase in the liabilities for remediation of environmental damage incurred by the Company could have a material adverse effect on the Company’s financial condition, results of operations or cash flows. Legal Proceedings In the normal course of its business and as a result of the extensive governmental regulation of the solid waste and E&P waste industries, the Company is subject to various judicial and administrative proceedings involving Canadian regulatory authorities as well as U.S. federal, state and local agencies. In these proceedings, an agency may subpoena the Company for records, or seek to impose fines on the Company or revoke or deny renewal of an authorization held by the Company, including an operating permit. From time to time, the Company may also be subject to actions brought by special interest or other groups, adjacent landowners or residents in connection with the permitting and licensing of landfills, transfer stations, and E&P waste treatment, recovery and disposal operations, or alleging environmental damage or violations of the permits and licenses pursuant to which the Company operates. The Company uses $1,000 as a threshold (up from the previously required threshold of $300) for disclosing environmental matters involving potential monetary sanctions. In addition, the Company is a party to various claims and suits pending for alleged damages to persons and property, alleged violations of certain laws and alleged liabilities arising out of matters occurring during the normal operation of the Company’s business. Except as noted in the matters described below, as of December 31, 2021, there is no current proceeding or litigation involving the Company or its property that the Company believes could have a material adverse effect on its business, financial condition, results of operations or cash flows. Lower Duwamish Waterway Superfund Site Allocation Process In November 2012, the Company’s subsidiary, Northwest Container Services, Inc. (“NWCS”), was named by the U.S. Environmental Protection Agency, Region 10 (the “EPA”) as a potentially responsible party (“PRP”), along with more than 100 others, under the Comprehensive Environmental Response, Compensation and Liability Act (“CERCLA” or the “Superfund” law) with respect to the Lower Duwamish Waterway Superfund Site (the “LDW Site”). Listed on the National Priorities List in 2001, the LDW Site is a five-mile stretch of the Duwamish River flowing into Elliott Bay in Seattle, Washington. A group of PRPs known as the Lower Duwamish Working Group (“LDWG”) and consisting of the City of Seattle, King County, the Port of Seattle, and Boeing Company conducted a Remedial Investigation/Feasibility Study for the LDW Site. On December 2, 2014, the EPA issued its Record of Decision (the “ROD”) describing the selected clean-up remedy, and therein estimated that clean-up costs (in present value dollars as of November 2014) would total approximately $342,000. However, it is possible that additional costs could be incurred based upon various factors. The EPA estimates that it will take seven years to implement the clean-up. The ROD also requires ten years of monitoring following the clean-up, and provides that if clean-up goals have not been met by the end of this period, then additional clean-up activities, at additional cost, may be required at that time. Implementation of the clean-up will not begin until after the ongoing Early Action Area (“EAA”) clean-ups have been completed. Typically, costs for monitoring may be in addition to those expended for the clean-up. While three of the EAA clean-ups have been completed to date, some work remains to be done on three other EAAs. Implementation of the clean-up also must await additional baseline sampling throughout the LDW Site and the preparation of a remedial design for performing the clean-up. On April 27, 2016, the LDWG entered into a third amendment of its Administrative Order on Consent with the EPA (the “AOC 3”) in which it agreed to perform the additional baseline sediment sampling and certain technical studies needed to prepare the actual remedial design. The LDWG and the EPA entered into a fourth amendment to the AOC in July 2018 primarily addressing development of a proposed remedy for the upper reach of the LDW Site, river mile 3 to river mile 5. At the April 24, 2019 stakeholders meeting, the LDWG projected that the remedial design for the upper reach could be completed by August 2024. In late September 2020, the EPA informed attorneys for several PRPs that the work may be completed by late 2023 or early 2024. On August 16, 2016, the EPA sent individual letters to each of the PRPs for the LDW Site, including NWCS, stating that it expected to initiate negotiations with all PRPs in early 2018 relating to a Remedial Design/Remedial Action (“RD/RA”) Consent Decree. An RD/RA Consent Decree provides for the cleanup of the entire site and is often referred to as a “global settlement.” In August 2014, NWCS entered into an Alternative Dispute Resolution Memorandum of Agreement with several dozen other PRPs and a neutral allocator to conduct a confidential and non-binding allocation of certain past response costs allegedly incurred at the LDW Site as well as the anticipated future response costs associated with the clean-up. In March 2017, the PRPs provided the EPA with notice that the allocation was not scheduled to conclude until mid-2019. Later extensions pushed the allocation conclusion date first to early 2020 and then to July 2020. The EPA was informed of those changes. The allocator issued his preliminary allocation report on June 28, 2021. The allocator is currently considering comments on the preliminary report, which the parties submitted in November 2021. The allocator may issue the final allocation report sometime in the next two months. In July 2021, the EPA was informed of the issuance of the preliminary allocation report in a telephone conference with allocation participants. In a telephone conference with allocation participants on December 14, 2021, the EPA stated its expectation that settlement negotiations would begin in the second half of 2022. NWCS is defending itself vigorously in this confidential allocation process. At this point, the Company is not able to determine the likelihood of the allocation process being completed as intended by the participating PRPs, its specific allocation, or the likelihood of the parties then negotiating a global settlement with the EPA. Thus, NWCS cannot reasonably determine the likelihood of any outcome in this matter, including its potential liability. On February 11, 2016, NWCS received a letter (the “Letter”) from the United States Department of Commerce, National Oceanic and Atmospheric Administration (“NOAA”), describing certain investigatory activities conducted by the Elliott Bay Trustee Council (the “Council”). The Council consists of all of the natural resources trustees for the LDW Site as well as two nearby Superfund sites, the Harbor Island site and the Lockheed West site. The members of the Council include the United States, on behalf of the U.S. National Oceanic and Atmospheric Administration and the U.S. Department of the Interior, the Washington State Department of Ecology, and the Suquamish and Muckleshoot Indian Tribes (together, the “Trustees”). The Letter appears to allege that NWCS may be a potentially liable party that allegedly contributed to the release of hazardous substances that have injured natural resources at the LDW Site. Damages to natural resources are in addition to clean-up costs. The Letter, versions of which NWCS believes were sent to all or a group of the PRPs for the LDW Site, also notified its recipients of their opportunity to participate in the Trustees’ development of an Assessment Plan and the performance of a Natural Resources Damages Assessment (“NRDA”) in accordance with the Assessment Plan for both the LDW Site and the east and west waterways of the Harbor Island site. NWCS timely responded with correspondence to the NOAA Office of General Counsel, in which it declined the invitation at that time. NWCS does not know how other PRPs responded to the Letter, and has not received any further communication from NOAA or the Trustees. The Trustees have not responded to NWCS’ letter. The Trustees released their Assessment Plan in March 2019. The Assessment Plan does not set forth a timeline for implementation. At this point, the Company is not able to determine the likelihood or amount of an assessment of natural resource damages against NWCS in connection with this matter. Los Angeles County, California Landfill Expansion Litigation A. Chiquita Canyon, LLC Lawsuit Against Los Angeles County In October 2004, the Company’s subsidiary, Chiquita Canyon, LLC (“CCL”), then under prior ownership, filed an application (the “Application”) with the County of Los Angeles (the “County”) Department of Regional Planning (“DRP”) for a conditional use permit (the “CUP”) to authorize the continued operation and expansion of the Chiquita Canyon Landfill (the “Landfill”). The Landfill has operated since 1972, and as a regional landfill, accepted approximately two and a half support facilities, construction of a facility for the County or another third-party operator to host household hazardous waste collection events, designation of an area for mixed organics/composting, and other modifications. After many years of reviews and delays, upon the recommendation of County staff, the County’s Regional Planning Commission (the “Commission”) approved the Application on April 19, 2017, but imposed operating conditions, fees and exactions that substantially reduce the historical landfill operations and represent a large increase in aggregate taxes and fees. CCL objected to many of the requirements imposed by the Commission. Current estimates for new costs imposed on CCL under the CUP are in excess of $300,000. CCL appealed the Commission’s decision to the County Board of Supervisors, but the appeal was not successful. At a subsequent hearing, on July 25, 2017, the Board of Supervisors approved the CUP. On October 20, 2017, CCL filed in the Superior Court of California, County of Los Angeles a verified petition for writ of mandate and complaint against the County and the County Board of Supervisors captioned Chiquita Canyon, LLC v. County of Los Angeles, No. BS171262 (Los Angeles Co. Super Ct.) (the “Complaint”). The Complaint challenges the terms of the CUP in 13 counts generally alleging that the County violated multiple California and federal statutes and California and federal constitutional protections. CCL seeks the following relief: (a) an injunction and writ of mandate against certain of the CUP’s operational restrictions, taxes and fees, (b) a declaration that the challenged conditions are unconstitutional and in violation of state and federal statutes, (c) reimbursement for any such illegal fees paid under protest, (d) damages, (e) an award of just compensation for a taking, (f) attorney fees, and (g) all other appropriate legal and equitable relief. Extensive motions practice and an interlocutory appeal occurred in 2018 and 2019 over the permissible scope of CCL’s challenge to the CUP, specifically 13 operational conditions in the CUP. The Superior Court ruled in CCL’s favor on November 13, 2019, finding that the County was estopped from contending that CCL has waived its rights to challenge the legality of the 13 operational conditions. The County sought interlocutory review of the Superior Court’s decision in the Court of Appeal, which denied the County’s petition on February 7, 2020. Following full briefing and oral argument on June 22, 2020 on six of CCL’s causes of action, the Superior Court issued its decision on July 2, 2020, granting CCL’s petition for writ of mandate in part and denying it in part. CCL prevailed with respect to 12 of the challenged conditions, many of which imposed new fees and exactions on the Landfill. Before entry of final judgment, the Superior Court will hear CCL’s remaining causes of action. A trial on CCL’s remaining causes of action is scheduled for August 1, 2022. Once the Superior Court has entered final judgment, CCL and the County will be permitted to appeal any adverse ruling to the California Court of Appeal. After entry of final judgment and resolution of any appeals, the Superior Court will issue a writ directing the County Board of Supervisors to set aside its decision on the permit with respect to 12 of the challenged conditions. The Board will be allowed to make additional findings to support four of those conditions and reconsider its permit decision in light of the Superior Court’s writ. CCL will continue to vigorously prosecute the lawsuit. However, at this point, the Company is not able to determine the likelihood of any outcome in this matter. B. December 11, 2017 Notice of Violation Regarding Certain CUP Conditions. The County, through its DRP, issued a Notice of Violation, dated December 11, 2017 (the “NOV”), alleging that CCL violated certain conditions of the CUP, including Condition 79(B)(6) of the CUP by failing to pay an $11,600 Bridge & Thoroughfare Fee (“B&T Fee”) that was purportedly due on July 25, 2017. The alleged B&T fee was ostensibly to fund the construction of transportation infrastructure in the area of the Landfill. At the time the NOV was issued, CCL had already contested the legality of the B&T fee in the October 20, 2017 Complaint filed against the County in Los Angeles County Superior Court, described above under paragraph A (the “CUP lawsuit”). On January 12, 2018, CCL filed an appeal of the alleged violations in the NOV. Subsequently, CCL filed additional legal arguments and exhibits contesting the NOV. On March 6, 2018, a DRP employee designated as hearing officer sustained the NOV, including the $11,600 B&T fee, and imposed an administrative penalty in the amount of $83 and a noncompliance fee of $0.75. A written decision memorializing the hearing officer’s findings and order was issued on July 10, 2018. On April 13, 2018, CCL filed in the Superior Court of California, County of Los Angeles a Petition for Writ of Administrative Mandamus against the County seeking to overturn the decision sustaining the NOV, contending that the NOV and decision are not supported by the facts or law. On July 17, 2018, the Court granted CCL leave to pay the $11,600 B&T fee and to amend its Complaint in the CUP lawsuit to reflect the payment under protest, allowing the challenge to the B&T fee under the Mitigation Fee Act to proceed in the CUP lawsuit. CCL paid the B&T fee under protest on August 10, 2018, and also paid on that date the administrative penalty of $83 and a noncompliance fee of $0.75. The Court indicated that the NOV case would be coordinated with the CUP lawsuit. The NOV case has been continued multiple times as the CUP lawsuit was adjudicated; it is now set for trial on June 16, 2022. The Superior Court’s July 2, 2020 decision in the CUP lawsuit upheld the B&T fee against a Mitigation Fee Act challenge, and addressed two other conditions that were also the subject of the NOV, which may impact the scope of the B&T fee/NOV case. CCL will continue to vigorously prosecute the lawsuit. However, at this point, the Company is not able to determine the likelihood of any outcome in this matter. Collective Bargaining Agreements Twenty-two of the Company’s collective bargaining agreements have expired or are set to expire in 2022. The Company does not expect any significant disruption in its overall business in 2022 as a result of labor negotiations, employee strikes or organizational efforts.

Shareholders' Equity

Shareholders' Equity	12 Months Ended
	Dec. 31, 2021
Shareholders' Equity [Abstract]
Shareholders' Equity	14. SHAREHOLDERS’ EQUITY Employee Share Purchase Plan On May 15, 2020, the Company’s shareholders approved the ESPP. Under the ESPP, qualified employees may elect to have payroll deductions withheld from their eligible compensation on each payroll date in amounts equal to or greater than one percent (1%) but not in excess of ten percent (10%) of eligible compensation in order to purchase the Company’s common shares under certain terms and subject to certain restrictions set forth in the ESPP. The exercise price is equal to 95% of the closing price of the Company’s common shares on the last day of the relevant offering period; provided, however, that such exercise price will not be less than 85% of the volume weighted average price of the Company’s common shares as reflected on the TSX over the final five trading days of such offering period. The maximum number of shares that may be issued under the ESPP is 1,000,000. Under the ESPP, employees purchased 10,813 of the Company’s common shares for $1,222 during the year ended December 31, 2021. Cash Dividend The Board of Directors of the Company authorized the initiation of a quarterly cash dividend in October 2010 and has increased it on an annual basis. In October 2021, the Company announced that its Board of Directors increased its regular quarterly cash dividend by $0.025, from $0.205 to $0.23 per Company common share. Cash dividends of $220,203, $199,883 and $175,067 were paid during the years ended December 31, 2021, 2020 and 2019, respectively. Normal Course Issuer Bid On July 27, 2021, the Board of Directors of the Company approved, subject to receipt of regulatory approvals, the annual renewal of the Company’s normal course issuer bid (the “NCIB”) to purchase up to 13,025,895 of the Company’s common shares during the period of August 10, 2021 to August 9, 2022 or until such earlier time as the NCIB is completed or terminated at the option of the Company. The renewal followed the conclusion of the Company’s NCIB that expired August 9, 2021. The Company received TSX approval for its annual renewal of the NCIB on August 6, 2021. Under the NCIB, the Company may make share repurchases only in the open market, including on the NYSE, the TSX, and/or alternative Canadian trading systems, at the prevailing market price at the time of the transaction. In accordance with TSX rules, any daily repurchases made through the TSX and alternative Canadian trading systems is limited to a maximum of 75,704 common shares, which represents 25% of the average daily trading volume on the TSX of 302,816 common shares for the period from February 1, 2021 to July 31, 2021. The TSX rules also allow the Company to purchase, once a week, a block of common shares not owned by any insiders, which may exceed such daily limit. The maximum number of shares that can be purchased per day on the NYSE will be 25% of the average daily trading volume for the four calendar weeks preceding the date of purchase, subject to certain exceptions for block purchases. The timing and amounts of any repurchases pursuant to the NCIB will depend on many factors, including the Company’s capital structure, the market price of the common shares and overall market conditions. All common shares purchased under the NCIB will be immediately cancelled following their repurchase. For the year ended December 31, 2021, the Company repurchased 3,003,822 common shares pursuant to the NCIB in effect during that period at an aggregate cost of $338,993. For the year ended December 31, 2020, the Company repurchased 1,271,977 common shares pursuant to the NCIB in effect during that period at an aggregate cost of $105,654. For the year ended December 31, 2019, the Company did not repurchase any common shares pursuant to the NCIB in effect during that period. As of December 31, 2021, the remaining maximum number of shares available for repurchase under the NCIB was 12,768,063. Common Shares The Company is authorized to issue an unlimited number of common shares, that have no par value, and uses reserved but unissued common shares to satisfy its obligations under its equity-based compensation plans. As of December 31, 2021, the Company has reserved the following common shares for issuance: ​ ​ ​ ​ For outstanding RSUs, PSUs and warrants 1,933,004 For future grants under the 2016 Incentive Award Plan 4,066,471 For future grants under the Employee Share Purchase Plan ​ 989,187 ​ 6,988,662 ​ Common Shares Held in Trust Common shares held in trust at December 31, 2021 consist of 70,662 shares of the Company held in a trust that were acquired by Progressive Waste prior to June 1, 2016 for the benefit of its U.S. and Canadian employees participating in certain share-based compensation plans. A total of 735,171 common shares were held in the trust on June 1, 2016 when it was acquired by the Company in the Progressive Waste acquisition. Common shares held in trust are classified as treasury shares in the Company’s Consolidated Balance Sheets. The Company will sell shares out of the trust and remit cash or shares to employees and non-employee directors as restricted share units vest and deferred share units settle, under the Progressive Waste share-based compensation plans that were continued by the Company. During the years ended December 31, 2021, 2020 and 2019, the Company sold 3,522, 7,330 and 48,375 common shares held in the trust, respectively, to settle vested restricted share units and deferred share units. Special Shares The Company is authorized to issue an unlimited number of special shares. Holders of special shares are entitled to one vote in matters of the Company for each special share held. The special shares carry no right to receive dividends or to receive the remaining property or assets of the Company upon dissolution or wind-up. At December 31, 2021, 2020 and 2019, no special shares were issued. Preferred Shares The Company is authorized to issue an unlimited number of preferred shares, issuable in series. Each series of preferred shares issued shall have rights, privileges, restrictions and conditions as determined by the Board of Directors prior to their issuance. Preferred shareholders are not entitled to vote, but take preference over the common shareholders rights in the remaining property and assets of the Company in the event of dissolution or wind-up. At December 31, 2021, 2020 and 2019, no preferred shares were issued. Restricted Share Units, Performance-Based Restricted Share Units, Share Options and Share Purchase Warrants In connection with the Progressive Waste acquisition, each Waste Connections US, Inc. restricted stock unit award, deferred restricted stock unit award and warrant outstanding immediately prior to the Progressive Waste acquisition was automatically converted into a restricted share unit award, deferred restricted share unit award or warrant, as applicable, relating to an equal number of common shares of the Company, on the same terms and conditions as were applicable immediately prior to the Progressive Waste acquisition under such equity award. Such conversion of equity awards was approved by the Company’s shareholders at its shareholder meeting as part of the shareholders’ approval of the Progressive Waste acquisition. At its meeting on June 1, 2016, the Company’s Board of Directors approved the assumption by the Company of the Waste Connections US, Inc. 2014 Incentive Plan Award (the “2014 Plan”), the Waste Connections US, Inc. Third Amended and Restated 2004 Equity Incentive Plan (the “2004 Plan”), and the Waste Connections US, Inc. Consultant Incentive Plan (the “Consultant Plan,” and, together with the 2014 Plan and the 2004 Plan, the “Assumed Plans”) for the purposes of administering the Assumed Plans and the awards issued thereunder. No additional awards will be made under any of the Assumed Plans. Upon the vesting, expiration, exercise in accordance with their terms or other settlement of all of the awards made pursuant to an Assumed Plan, such Assumed Plan shall automatically terminate. Participation in the 2004 Plan was limited to employees, officers, directors and consultants. Restricted share units (“RSUs”) granted under the 2004 Plan generally vest in installments pursuant to a vesting schedule set forth in each agreement. The Board of Directors authorized the granting of awards under the 2004 Plan, and determined the employees and consultants to whom such awards were to be granted, the number of shares subject to each award, and the exercise price, term, vesting schedule and other terms and conditions of each award. RSU awards granted under the plan did not require any cash payment from the participant to whom an award was made. No grants have been made under the 2004 Plan since May 16, 2014 pursuant to the approval by the stockholders of the 2014 Plan on such date. The 2014 Plan also authorized the granting of RSUs, as well as performance awards payable in the form of the Company’s common shares or cash, including equity awards and incentive cash bonuses that may have been intended to qualify as “performance-based compensation” under Section 162(m) of the Internal Revenue Code of 1986, as amended (“Section 162(m)”). Participation in the 2014 Plan was limited to employees and consultants of the Company and its subsidiaries and non-employee directors. The 2014 Plan is administered by the Company’s Board of Directors with respect to awards to non-employee directors and by its Compensation Committee with respect to other participants, each of which may delegate its duties and responsibilities to committees of the Company’s directors and/or officers, subject to certain limitations (collectively, the “administrator”). RSUs granted under the 2014 Plan generally vest in installments pursuant to a vesting schedule set forth in each award agreement. RSU awards under the 2014 plan do not require any cash payment from the participant to whom an award was made. The vesting of performance awards, including performance-based restricted share units (“PSUs”), was dependent on one or more performance criteria determined by the administrator on a specific date or dates or over any period or periods determined by the administrator. On June 1, 2016, the Company’s Board of Directors adopted the 2016 Incentive Award Plan (the “2016 Plan”), which was approved by Progressive Waste’s shareholders on May 26, 2016. On each of July 24, 2017 and 2018, the Board of Directors approved certain housekeeping amendments to the 2016 Plan. The 2016 Plan, as amended, is administered by the Company’s Compensation Committee and provides that the aggregate number of common shares which may be issued from treasury pursuant to awards made under the 2016 Plan is 7,500,000 common shares. Awards under the 2016 Plan may be made to employees, consultants and non-employee directors and may be made in the form of options, warrants, restricted shares, restricted share units, performance awards (which may be paid in cash, common shares, or a combination thereof), dividend equivalent awards (representing a right of the holder thereof to receive the equivalent value (which may be paid in cash or common shares) of dividends paid on common shares), and share payments (a payment in the form of common shares or an option or other right to purchase common shares as part of a bonus, defined compensation or other arrangement). Non-employee directors are also eligible to receive deferred share units, which represent the right to receive a cash payment or its equivalent in common shares (or a combination of cash and common shares), or which may at the time of grant be expressly limited to settlement only in cash and not in common shares. Restricted Share Units A summary of the Company’s RSU activity is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 2020 2019 Weighted average grant-date fair value of restricted share units granted ​ $ 100.27 ​ $ 101.79 ​ $ 81.24 Total fair value of restricted share units vested ​ $ 26,711 ​ $ 23,742 ​ $ 21,136 ​ A summary of activity related to RSUs during the year ended December 31, 2021, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ Grant Date Fair ​ Unvested Shares ​ Value Per Share Outstanding at December 31, 2020 772,625 ​ $ 84.61 Granted 498,078 ​ $ 100.27 Forfeited (65,528) ​ $ 94.63 Vested and issued (343,480) ​ $ 77.76 Outstanding at December 31, 2021 861,695 ​ $ 95.63 ​ Recipients of the Company’s RSUs who participate in the Company’s Nonqualified Deferred Compensation Plan may have elected in years prior to 2015 to defer some or all of their RSUs as they vest until a specified date or dates they choose. At the end of the deferral periods, unless a qualified participant makes certain other elections, the Company issues to recipients who deferred their RSUs common shares of the Company underlying the deferred RSUs. At December 31, 2021, 2020 and 2019, the Company had 100,861, 177,760 and 247,999 vested deferred RSUs outstanding, respectively. Performance-Based Restricted Share Units A summary of the Company’s PSU activity is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 2020 2019 Weighted average grant-date fair value of PSUs granted ​ $ 96.99 ​ $ 87.19 ​ $ 80.85 Total fair value of PSUs vested ​ $ 10,954 ​ $ 15,628 ​ $ 7,683 ​ A summary of activity related to PSUs during the year ended December 31, 2021, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ Grant Date Fair ​ Unvested Shares ​ Value Per Share Outstanding at December 31, 2020 434,558 ​ $ 82.60 Granted 116,784 ​ $ 96.99 Forfeited (5,048) ​ $ 68.58 Vested and issued (154,251) ​ $ 71.01 Outstanding at December 31, 2021 392,043 ​ $ 91.63 ​ During the year ended December 31, 2021, the Company’s Compensation Committee granted PSUs with three-year performance-based metrics that the Company must meet before those awards may be earned, and the performance period for those grants ends on December 31, 2023. During the year ended December 31, 2020, the Company’s Compensation Committee granted PSUs with three-year performance-based metrics that the Company must meet before those awards may be earned, and the performance period for those grants ends on December 31, 2022. During the same period, the Company’s Compensation Committee also granted PSUs with a one-year performance-based metric that the Company was required to meet before those awards were earned, with the awards then subject to time-based vesting for the remaining three years of their four-year vesting period. During the year ended December 31, 2019, the Company’s Compensation Committee granted PSUs with three-year performance-based metrics that the Company was required to meet before those awards were earned, and the performance period for those grants ended on December 31, 2021. During the same period, the Company’s Compensation Committee also granted PSUs with a one-year performance-based metric that the Company was required to meet before those awards were earned, with the awards then subject to time-based vesting for the remaining three years of their four-year vesting period. The Compensation Committee determines the achievement of performance results and corresponding vesting of PSUs for each performance period. Share Purchase Warrants The Company has outstanding share purchase warrants issued under the 2016 Plan. Warrants to purchase the Company’s common shares were issued to certain consultants to the Company. Warrants issued were fully vested and exercisable at the date of grant. Warrants outstanding at December 31, 2021, expire between 2022 and 2026. A summary of warrant activity during the year ended December 31, 2021, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ Warrants ​ Exercise Price Outstanding at December 31, 2020 489,748 ​ $ 86.41 Granted 218,166 ​ $ 110.91 Forfeited (82,779) ​ $ 81.35 Exercised (46,730) ​ $ 72.88 Outstanding at December 31, 2021 578,405 ​ $ 104.82 ​ The following table summarizes information about warrants outstanding as of December 31, 2021 and 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value of ​ ​ ​ ​ ​ ​ Warrants ​ ​ ​ Warrants ​ Outstanding at December 31, Grant Date ​ Issued ​ Exercise Price ​ Issued ​ 2021 ​ 2020 Throughout 2016 15,666 ​ $42.22 to $51.55 ​ $ 189 — 7,158 Throughout 2017 35,382 ​ $53.65 to $69.96 ​ $ 595 1,521 33,551 Throughout 2018 163,995 ​ $70.91 to $80.90 ​ $ 2,591 112,756 133,141 Throughout 2019 ​ 151,008 ​ $74.25 to $95.61 ​ $ 2,634 ​ 101,977 ​ 151,008 Throughout 2020 ​ 164,890 ​ $72.65 to $104.89 ​ $ 3,140 ​ 146,386 ​ 164,890 Throughout 2021 ​ 218,166 ​ $99.33 to $135.97 ​ $ 5,584 ​ 215,765 ​ — ​ ​ ​ ​ ​ ​ ​ 578,405 489,748 ​ Deferred Share Units A summary of the Company’s deferred share units (“DSUs”) activity is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 ​ 2020 2019 Weighted average grant-date fair value of DSUs granted ​ $ 99.80 ​ $ 103.81 ​ $ 83.80 Total fair value of DSUs awarded ​ $ 285 ​ $ 272 ​ $ 319 ​ The DSUs consist of a combination of DSU grants outstanding under the Progressive Waste share-based compensation plans that were continued by the Company following the Progressive Waste acquisition and DSUs granted by the Company since the Progressive Waste acquisition. A summary of activity related to DSUs during the year ended December 31, 2021, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ Grant Date Fair ​ Vested Shares ​ Value Per Share Outstanding at December 31, 2020 21,586 ​ $ 59.32 Granted 2,856 ​ $ 99.80 Outstanding at December 31, 2021 24,442 ​ $ 64.05 ​ Other Restricted Share Units RSU grants outstanding under the Progressive Waste share-based compensation plans were continued by the Company following the Progressive Waste acquisition and allow for the issuance of shares or cash settlement to employees upon vesting. A summary of activity related to Progressive Waste RSUs during the year ended December 31, 2021, is presented below: ​ ​ ​ ​ Outstanding at December 31, 2020 66,554 Cash settled (3,522) Outstanding at December 31, 2021 63,032 ​ No RSUs under the Progressive Waste share-based compensation plans were granted subsequent to June 1, 2016. All remaining RSUs were vested as of December 31, 2019. Share Based Options Share based options outstanding under the Progressive Waste share-based compensation plans were continued by the Company following the Progressive Waste acquisition and allow for the issuance of shares or cash settlement to employees upon vesting. A summary of activity related to Progressive Waste share based options during the year ended December 31, 2021, is presented below: ​ ​ ​ ​ Outstanding at December 31, 2020 51,200 Cash settled (5,331) Outstanding at December 31, 2021 45,869 ​ No share based options under the Progressive Waste share-based compensation plans were granted subsequent to June 1, 2016. All outstanding share based options were vested as of December 31, 2017.

Other Comprehensive Income (Los

Other Comprehensive Income (Loss)	12 Months Ended
	Dec. 31, 2021
Other Comprehensive Income (Loss) [Abstract]
Other Comprehensive Income (Loss)	15. OTHER COMPREHENSIVE INCOME (LOSS) Other comprehensive income (loss) includes changes in the fair value of interest rate swaps that qualify for hedge accounting. The components of other comprehensive income (loss) and related tax effects for the years ended December 31, 2021, 2020 and 2019, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2021 ​ Gross Tax Effect Net of Tax Interest rate swap amounts reclassified into interest expense ​ $ 20,321 ​ $ (5,385) ​ $ 14,936 Changes in fair value of interest rate swaps ​ 23,287 ​ (6,171) ​ 17,116 Foreign currency translation adjustment ​ 8,183 ​ — ​ 8,183 ​ ​ $ 51,791 ​ $ (11,556) ​ $ 40,235 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2020 ​ Gross Tax Effect Net of Tax Interest rate swap amounts reclassified into interest expense ​ $ 9,778 ​ $ (2,591) ​ $ 7,187 Changes in fair value of interest rate swaps ​ (64,664) ​ 17,136 ​ (47,528) Foreign currency translation adjustment ​ 50,653 ​ — ​ 50,653 ​ ​ $ (4,233) ​ $ 14,545 ​ $ 10,312 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2019 ​ Gross Tax Effect Net of Tax Interest rate swap amounts reclassified into interest expense ​ $ (8,027) ​ $ 2,127 ​ $ (5,900) Changes in fair value of interest rate swaps ​ (43,873) ​ 11,626 ​ (32,247) Foreign currency translation adjustment ​ ​ 101,970 ​ ​ — ​ ​ 101,970 ​ ​ $ 50,070 ​ $ 13,753 ​ $ 63,823 ​ A roll forward of the amounts included in AOCIL, net of taxes, is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Foreign Accumulated ​ ​ ​ ​ ​ Currency ​ Other ​ ​ Interest ​ Translation ​ Comprehensive ​ ​ Rate Swaps ​ Adjustment ​ Income (Loss) Balance at December 31, 2019 ​ $ (29,255) ​ $ 18,292 ​ $ (10,963) Amounts reclassified into earnings ​ 7,187 ​ — ​ 7,187 Changes in fair value ​ (47,528) ​ — ​ (47,528) Foreign currency translation adjustment ​ — ​ 50,653 ​ 50,653 Balance at December 31, 2020 ​ ​ (69,596) ​ ​ 68,945 ​ ​ (651) Amounts reclassified into earnings ​ ​ 14,936 ​ ​ — ​ ​ 14,936 Changes in fair value ​ ​ 17,116 ​ ​ — ​ ​ 17,116 Foreign currency translation adjustment ​ ​ — ​ ​ 8,183 ​ ​ 8,183 Balance at December 31, 2021 ​ $ (37,544) ​ $ 77,128 ​ $ 39,584 ​

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2021
Income Taxes [Abstract]
Income Taxes	16. INCOME TAXES The Company’s operations are conducted through its various subsidiaries in countries throughout the world. The Company has provided for income taxes based upon the tax laws and rates in the countries in which operations are conducted and income is earned. Income before provision for income taxes consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 2020 2019 U.S. ​ $ 574,737 ​ $ 22,349 ​ $ 477,203 Non – U.S. ​ 196,005 ​ 231,565 ​ 228,688 Income before income taxes ​ $ 770,742 ​ $ 253,914 ​ $ 705,891 ​ The provision for income taxes consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 2020 2019 Current: ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. Federal ​ $ 71,180 ​ $ 65,143 ​ $ 45,475 State ​ 34,439 ​ 28,325 ​ 27,528 Non – U.S. ​ 32,071 ​ 6,941 ​ 11,570 ​ ​ 137,690 ​ 100,409 ​ 84,573 Deferred: ​ ​ ​ U.S. Federal ​ 51,534 ​ (36,659) ​ 58,291 State ​ 5,093 ​ (8,762) ​ 6,331 Non – U.S. ​ (42,064) ​ (5,066) ​ (9,985) ​ ​ 14,563 ​ (50,487) ​ 54,637 Provision for income taxes ​ $ 152,253 ​ $ 49,922 ​ $ 139,210 ​ The Company is organized under the laws of Ontario, Canada; however, since the proportion of U.S. revenues, assets, operating income and associated tax provisions is significantly greater than any other single taxing jurisdiction within the worldwide group, the reconciliation of the differences between the Company’s income tax provision as presented in the accompanying Consolidated Statements of Net Income and income tax provision computed at the federal statutory rate is presented on the basis of the U.S. federal statutory income tax rate of 21%, as opposed to the Canadian statutory rate of approximately 27% to provide a more meaningful insight into those differences. The items shown in the following table are a percentage of pre-tax income: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 2020 2019 U.S. federal statutory rate ​ 21.0 % 21.0 % 21.0 % State taxes, net of federal benefit 4.7 4.5 4.4 ​ Deferred income tax liability adjustments 0.3 1.6 0.6 ​ Effect of international operations (6.3) (7.0) (6.3) ​ Other 0.1 (0.4) — ​ ​ 19.8 % 19.7 % 19.7 % ​ The comparability of the Company’s income tax provision for the reported periods has been affected by variations in its income before income taxes. The effects of international operations are primarily due to a portion of the Company’s income from internal financing that is taxed at effective rates substantially lower than the U.S. federal statutory rate. For the year ended December 31, 2020, the Company’s income tax provision included a $27,358 expense associated with certain 2019 inter-entity payments no longer being deductible for tax purposes due to the finalization of tax regulations on April 7, 2020 under Internal Revenue Code Section 267A and a $4,148 expense related to an increase in the Company’s deferred income tax liabilities resulting from the impairment of certain assets within its E&P waste operations which impacted the geographical apportionment of its state income taxes. Additionally, for the year ended December 31, 2019, a reduction in deferred income tax assets primarily related to compensation of executive officers no longer deemed deductible for tax purposes resulted in an increase to tax expense of $3,805. The significant components of deferred income tax assets and liabilities, reduced by valuation allowances as applicable, are presented below. ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2021 2020 Deferred income tax assets: ​ ​ Accrued expenses ​ $ 31,840 ​ $ 26,600 Compensation ​ 22,545 ​ 18,150 Contingent liabilities ​ 21,268 ​ 17,652 Tax credits and loss carryforwards ​ 24,415 ​ 24,044 Interest rate and fuel hedges ​ 13,536 ​ 25,093 Finance costs ​ 24,264 ​ — Other ​ ​ — ​ ​ 872 Gross deferred income tax assets ​ 137,868 ​ 112,411 Less: Valuation allowance ​ — ​ — Total deferred income tax assets ​ 137,868 ​ 112,411 ​ ​ ​ ​ ​ ​ ​ Deferred income tax liabilities: ​ ​ ​ ​ ​ ​ Goodwill and other intangibles ​ (397,855) ​ (332,097) Property and equipment ​ (484,519) ​ (440,019) Landfill closure/post-closure ​ (18,597) ​ (13,846) Prepaid expenses ​ (11,534) ​ (14,990) Investment in subsidiaries ​ (69,286) ​ (69,391) Finance costs ​ ​ — ​ ​ (2,112) Other ​ ​ (6,998) ​ ​ — Total deferred income tax liabilities ​ (988,789) ​ (872,455) Net deferred income tax liability ​ $ (850,921) ​ $ (760,044) ​ The Company has $47,966 of Canadian tax loss carryforwards with a 20-year carryforward period which will begin to expire in 2036, as well as various U.S. state tax losses with carryforward periods up to 20 years. As of December 31, 2021, the Company had undistributed earnings of approximately $2,860,889 for which income taxes have not been provided on permanently reinvested earnings of approximately $1,685,889. Additionally, the Company has not recorded deferred taxes on the amount of financial reporting basis in excess of tax basis of approximately $340,308 attributable to the Company’s non-U.S. subsidiaries which are permanently reinvested. It is not practical to estimate the additional tax that may become payable upon the eventual repatriation of these amounts; however, the tax impacts could result in a material increase to the Company’s effective tax rate. The Company and its subsidiaries are subject to U.S. federal and Canadian income tax, which are its principal operating jurisdictions. The Company has concluded all U.S. federal income tax matters for years through 2017. Additionally, the normal reassessment period for the Company has expired for all Canadian federal income tax matters for years through 2016. The Company did not have any unrecognized tax benefits recorded at December 31, 2021, 2020 or 2019. The Company does not anticipate the total amount of unrecognized tax benefits will significantly change by December 31, 2022. The Company recognizes interest and/or penalties related to income tax matters in income tax expense.

Segment Reporting

Segment Reporting	12 Months Ended
	Dec. 31, 2021
Segment Reporting [Abstract]
Segment Reporting	17. SEGMENT REPORTING The Company’s revenues are generated from the collection, transfer, recycling and disposal of non-hazardous solid waste and the treatment, recovery and disposal of non-hazardous E&P waste. No The Company manages its operations through the following five geographic solid waste operating segments: Eastern, Southern, Western, Central and Canada. The Company’s five geographic solid waste operating segments comprise its reportable segments. Each operating segment is responsible for managing several vertically integrated operations, which are comprised of districts. The Company’s Chief Operating Decision Maker evaluates operating segment profitability and determines resource allocations based on several factors, of which the primary financial measure is segment EBITDA. The Company defines segment EBITDA as earnings before interest, taxes, depreciation, amortization, impairments and other operating items, other income (expense) and loss on early extinguishment of debt. Segment EBITDA is not a measure of operating income, operating performance or liquidity under GAAP and may not be comparable to similarly titled measures reported by other companies. The Company’s management uses segment EBITDA in the evaluation of segment operating performance as it is a profit measure that is generally within the control of the operating segments. A reconciliation of segment EBITDA to Income before income tax provision is included at the end of this Note 17. Summarized financial information concerning the Company’s reportable segments for the years ended December 31, 2021, 2020 and 2019, is shown in the following tables: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ Intercompany ​ Reported ​ Segment ​ Depreciation and ​ Capital ​ ​ ​ December 31, 2021 Revenue Revenue (b) Revenue EBITDA (c) Amortization Expenditures Total Assets (e) Eastern ​ $ 1,807,563 ​ $ (286,275) ​ $ 1,521,288 ​ $ 404,493 ​ $ 239,130 ​ $ 174,350 ​ $ 3,652,311 Southern ​ ​ 1,633,402 ​ ​ (186,656) ​ ​ 1,446,746 ​ ​ 394,982 ​ ​ 188,977 ​ ​ 156,527 ​ ​ 3,513,355 Western ​ 1,434,844 ​ (154,656) ​ 1,280,188 ​ 405,778 ​ 129,988 ​ 152,149 ​ 2,260,222 Central ​ 1,188,501 ​ (142,085) ​ 1,046,416 ​ 359,434 ​ 134,078 ​ 144,458 ​ 2,332,564 Canada ​ 965,705 ​ (108,982) ​ 856,723 ​ 339,859 ​ 111,458 ​ 68,183 ​ 2,513,608 Corporate (a), (d) ​ — ​ — ​ — ​ (19,596) ​ 9,378 ​ 48,648 ​ 427,864 ​ ​ $ 7,030,015 ​ $ (878,654) ​ $ 6,151,361 ​ $ 1,884,950 ​ $ 813,009 ​ $ 744,315 ​ $ 14,699,924 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ Intercompany ​ Reported ​ Segment ​ Depreciation and ​ Capital ​ ​ ​ December 31, 2020 Revenue Revenue (b) Revenue EBITDA (c) Amortization Expenditures Total Assets (e) Eastern ​ $ 1,601,980 ​ $ (266,115) ​ $ 1,335,865 ​ $ 343,446 ​ $ 222,934 ​ $ 181,787 ​ $ 3,134,462 Southern ​ ​ 1,552,687 ​ ​ (183,107) ​ ​ 1,369,580 ​ ​ 369,445 ​ ​ 189,726 ​ ​ 131,831 ​ ​ 3,402,081 Western ​ 1,291,882 ​ (142,120) ​ 1,149,762 ​ 364,790 ​ 115,151 ​ 132,344 ​ 1,861,079 Central ​ 1,008,081 ​ (127,758) ​ 880,323 ​ 313,033 ​ 113,004 ​ 102,966 ​ 2,160,246 Canada ​ 805,757 ​ (95,297) ​ 710,460 ​ 256,119 ​ 103,334 ​ 109,886 ​ 2,544,379 Corporate (a), (d) ​ — ​ — ​ — ​ (15,283) ​ 8,255 ​ 5,747 ​ 890,117 ​ ​ $ 6,260,387 ​ $ (814,397) ​ $ 5,445,990 ​ $ 1,631,550 ​ $ 752,404 ​ $ 664,561 ​ $ 13,992,364 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ Intercompany ​ Reported ​ Segment ​ Depreciation and ​ Capital ​ ​ ​ December 31, 2019 Revenue Revenue (b) Revenue EBITDA (c) Amortization Expenditures Total Assets (e) Eastern ​ $ 1,524,648 ​ $ (255,684) ​ $ 1,268,964 ​ $ 330,578 ​ $ 204,221 ​ $ 154,218 ​ $ 3,099,283 Southern ​ ​ 1,623,614 ​ ​ (174,614) ​ ​ 1,449,000 ​ ​ 441,425 ​ ​ 208,967 ​ ​ 178,127 ​ ​ 3,952,449 Western ​ 1,234,669 ​ (135,820) ​ 1,098,849 ​ 338,563 ​ 102,067 ​ 147,893 ​ 1,718,015 Central ​ 958,139 ​ (119,555) ​ 838,584 ​ 292,111 ​ 106,391 ​ 116,831 ​ 1,885,468 Canada ​ 835,603 ​ (102,321) ​ 733,282 ​ 256,405 ​ 113,944 ​ 61,119 ​ 2,490,291 Corporate (a), (d) ​ — ​ — ​ — ​ (15,438) ​ 8,328 ​ 7,901 ​ 592,189 ​ ​ $ 6,176,673 ​ $ (787,994) ​ $ 5,388,679 ​ $ 1,643,644 ​ $ 743,918 ​ $ 666,089 ​ $ 13,737,695 (a) The majority of Corporate expenses are allocated to the five operating segments. Direct acquisition expenses, expenses associated with common shares held in the deferred compensation plan exchanged for other investment options and share-based compensation expenses associated with Progressive Waste share-based grants outstanding at June 1, 2016 that were continued by the Company are not allocated to the five operating segments and comprise the net EBITDA of the Company’s Corporate segment for the periods presented. (b) Intercompany revenues reflect each segment’s total intercompany sales, including intercompany sales within a segment and between segments. Transactions within and between segments are generally made on a basis intended to reflect the market value of the service. (c) For those items included in the determination of segment EBITDA, the accounting policies of the segments are the same as those described in Note 3. (d) Corporate assets include cash, debt issuance costs, equity investments, operating lease right-of-use assets and corporate facility leasehold improvements and equipment. (e) Goodwill is included within total assets for each of the Company’s five operating segments. The following table shows changes in goodwill during the years ended December 31, 2020 and 2021, by reportable segment: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Eastern Southern Western Central Canada Total Balance as of December 31, 2019 ​ $ 1,331,180 ​ $ 1,528,225 ​ $ 400,037 ​ $ 729,470 ​ $ 1,521,939 ​ $ 5,510,851 Goodwill acquired ​ 43,397 ​ 3,990 ​ 42,825 ​ 94,883 ​ 208 ​ 185,303 Goodwill divested ​ ​ — ​ ​ — ​ ​ — ​ ​ (149) ​ ​ — ​ ​ (149) Impact of changes in foreign currency ​ — ​ — ​ — ​ — ​ 30,645 ​ 30,645 Balance as of December 31, 2020 ​ ​ 1,374,577 ​ ​ 1,532,215 ​ ​ 442,862 ​ ​ 824,204 ​ ​ 1,552,792 ​ ​ 5,726,650 Goodwill acquired ​ 233,146 ​ 56,576 ​ ​ 96,870 ​ 68,005 ​ ​ — ​ 454,597 Goodwill acquisition adjustments ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ (2) ​ ​ (2) Goodwill divested ​ — ​ (324) ​ — ​ — ​ — ​ (324) Impact of changes in foreign currency ​ — ​ — ​ — ​ — ​ 6,722 ​ 6,722 Balance as of December 31, 2021 ​ $ 1,607,723 ​ $ 1,588,467 ​ $ 539,732 ​ $ 892,209 ​ $ 1,559,512 ​ $ 6,187,643 ​ Property and equipment, net relating to operations in the United States and Canada are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2021 2020 United States ​ $ 5,075,184 ​ $ 4,589,144 Canada ​ 646,765 ​ 695,362 Total ​ $ 5,721,949 ​ $ 5,284,506 ​ A reconciliation of the Company’s primary measure of segment profitability (segment EBITDA) to Income before income tax provision in the Consolidated Statements of Net Income is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years ended December 31, ​ 2021 2020 2019 Eastern segment EBITDA ​ $ 404,493 ​ $ 343,446 ​ $ 330,578 Southern segment EBITDA ​ ​ 394,982 ​ ​ 369,445 ​ ​ 441,425 Western segment EBITDA ​ 405,778 ​ 364,790 ​ 338,563 Central segment EBITDA ​ 359,434 ​ 313,033 ​ 292,111 Canada segment EBITDA ​ 339,859 ​ 256,119 ​ 256,405 Subtotal reportable segments ​ 1,904,546 ​ 1,646,833 ​ 1,659,082 Unallocated corporate overhead ​ (19,596) ​ (15,283) ​ (15,438) Depreciation ​ (673,730) ​ (621,102) ​ (618,396) Amortization of intangibles ​ (139,279) ​ (131,302) ​ (125,522) Impairments and other operating items ​ (32,316) ​ (466,718) ​ (61,948) Interest expense ​ (162,796) ​ (162,375) ​ (147,368) Interest income ​ 2,916 ​ 5,253 ​ 9,777 Other income (expense), net ​ 6,285 ​ (1,392) ​ 5,704 Loss on early extinguishment of debt ​ ​ (115,288) ​ ​ — ​ ​ — Income before income tax provision ​ $ 770,742 ​ $ 253,914 ​ $ 705,891 ​

Net Income Per Share Informatio

Net Income Per Share Information	12 Months Ended
	Dec. 31, 2021
Net Income Per Share Information [Abstract]
Net Income Per Share Information	18. NET INCOME PER SHARE INFORMATION The following table sets forth the calculation of the numerator and denominator used in the computation of basic and diluted net income per common share attributable to the Company’s shareholders for the years ended December 31, 2021, 2020 and 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 2020 2019 Numerator: ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income attributable to Waste Connections for basic and diluted earnings per share ​ $ 618,047 ​ $ 204,677 ​ $ 566,841 Denominator: ​ ​ ​ ​ ​ ​ Basic shares outstanding ​ 261,166,723 ​ 263,189,699 ​ 263,792,693 Dilutive effect of equity-based awards ​ 561,747 ​ 497,840 ​ 733,868 Diluted shares outstanding ​ 261,728,470 ​ 263,687,539 ​ 264,526,561 ​

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2021
Employee Benefit Plans [Abstract]
Employee Benefit Plans	19. EMPLOYEE BENEFIT PLANS Retirement Savings Plans: Certain of Waste Connections’ subsidiaries also have voluntary savings and investment plans in the U.S. (the “401(k) Plans”). The 401(k) Plans are available to all eligible U.S. employees of Waste Connections and its subsidiaries. Waste Connections and its subsidiaries make matching contributions under the 401(k) Plans of 100% of every dollar of a participating employee’s pre-tax contributions until the employee’s contributions equal 5% of the employee’s eligible compensation, subject to certain limitations imposed by the U.S. Internal Revenue Code. The Company’s matching contributions under the 401(k) Plans were suspended from June 1, 2020 to December 31, 2020. The Company reinstated its matching contributions effective January 1, 2021. Total employer expenses, including employer matching contributions, for the DPSP and 401(k) Plans were $31,834, $16,350 and $26,111, respectively, during the years ended December 31, 2021, 2020 and 2019. These amounts include matching contributions Waste Connections made under the Deferred Compensation Plan, described below. Multiemployer Pension Plans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Expiration ​ ​ EIN/Pension Plan ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Date of ​ ​ Number/ ​ Pension Protection Act ​ FIP/RP ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Collective ​ ​ Registration ​ Zone Status (a) ​ Status ​ Company Contributions (d) ​ Bargaining Plan Name Number 2021 2020 (b),(c) 2021 2020 2019 Agreement Western Conference of Teamsters Pension Trust 91-6145047 - 001 Green Green Not applicable ​ $ 4,963 ​ $ 4,841 ​ $ 4,550 12/31/2021 to 6/30/2025 Local 731, I.B. of T., Pension Fund 36-6513567 - 001 Green for the plan year beginning 10/1/2021 Green for the plan year beginning 10/1/2019 Not applicable ​ ​ 4,504 ​ ​ 4,628 ​ ​ 4,570 9/30/2023 Suburban Teamsters of Northern Illinois Pension Fund 36-6155778 - 001 Green Green Not applicable ​ 2,300 ​ 2,080 ​ 1,844 2/29/2024 Teamsters Local 301 Pension Fund 36-6492992 - 001 Green Green Not applicable ​ 841 ​ 673 ​ 624 9/30/2023 Automobile Mechanics’ Local No. 701 Union and Industry Pension Fund 36-6042061 - 001 Green Green Not applicable ​ 439 ​ 457 ​ 492 12/31/2022 Midwest Operating Engineers Pension Plan 36-6140097 - 001 Green for the plan year beginning 4/1/2021 Green for the plan year beginning 4/1/2020 Not applicable ​ 424 ​ 316 ​ 339 10/31/2025 Locals 302 & 612 of the IOUE - Employers Construction Industry Retirement Plan 91-6028571 - 001 Green Green Not applicable ​ 313 ​ 298 ​ 290 11/16/2022 IAM National Pension Fund ​ 51-6031295 - 002 ​ Critical ​ Critical ​ Implemented ​ ​ 299 ​ ​ 310 ​ ​ 256 ​ 12/31/2022 International Union of Operating Engineers Pension Trust 85512-1 Green as of 4/30/2020 Green as of 4/30/2018 Not applicable ​ 295 ​ 279 ​ 238 3/31/2021 to 3/31/2024 Multi-Sector Pension Plan 1085653 Green as of 1/1/2021 Green as of 1/1/2020 Not applicable ​ 265 ​ 196 ​ 202 12/31/2023 Local 813 Pension Trust Fund 13-1975659 - 001 Critical for the plan year beginning 1/1/2021 Critical Implemented ​ 258 ​ 183 ​ 281 11/30/2022 Recycling and General Industrial Union Local 108 Pension Fund ​ 13-6366378 ​ Green ​ Green ​ Not applicable ​ ​ 217 ​ ​ 269 ​ ​ 337 ​ 2/28/2022 Nurses and Local 813 IBT Retirement Plan ​ 13-3628926 - 001 ​ Green ​ Green ​ Not applicable ​ ​ 58 ​ ​ 52 ​ ​ 87 ​ 11/30/2022 Contributions to other multiemployer plans ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 75 ​ ​ 10 ​ ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 15,251 ​ $ 14,592 ​ $ 14,110 ​ ​ ​ (a) Unless otherwise noted in the table above, the most recent Pension Protection Act zone status available in 2021 and 2020 is for the plans’ years ended December 31, 2020 and 2019, respectively. (b) The “FIP/RP Status” column indicates plans for which a Funding Improvement Plan (“FIP”) or a Rehabilitation Plan (“RP”) has been implemented. (c) A multiemployer defined benefit pension plan that has been certified as endangered, seriously endangered or critical may begin to levy a statutory surcharge on contribution rates. Once authorized, the surcharge is at the rate of 5% for the first 12 months and 10% for any periods thereafter, until certain conditions are met. The Company was not required to pay a surcharge to these plans during the years ended December 31, 2021 and 2020. (d) Of the Multiemployer Pension Plans considered to be individually significant, the Company was listed in the Form 5500 as providing more than 5% of the total contributions for the following: 1) Local No. 731, I.B. of T., Pension Fund for plan years ending September 30, 2020, 2019 and 2018; 2) Teamsters Local 301 Pension Fund for plan years ending December 31, 2020, 2019 and 2018; 3) Suburban Teamsters of Northern Illinois Pension Plan for the plan year ending December 31, 2020; and 4) Recycling and General Industrial Union Local 108 Pension Fund for the plan years ending December 31, 2020, 2019 and 2018. The status is based on information that the Company received from the pension plans and is certified by the pension plans’ actuary. Plans with “green” status are at least 80% funded. Plans with “yellow” status are less than 80% funded. Plans with “critical” status are less than 65% funded. Under current law regarding multiemployer benefit plans, a plan’s termination, the Company’s voluntary withdrawal, or the withdrawal of all contributing employers from any under-funded multiemployer pension plan would require the Company to make payments to the plan for its proportionate share of the multiemployer plan’s unfunded vested liabilities. The Company could have adjustments to its estimates for these matters in the near term that could have a material effect on its consolidated financial condition, results of operations or cash flows. Deferred Compensation Plan:

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2021
Subsequent Events [Abstract]
Subsequent Events	20. SUBSEQUENT EVENTS On February 16, 2022, the Company announced that its Board of Directors approved a regular quarterly cash dividend of $0.23 per Company common share. The dividend will be paid on March 16, 2022, to shareholders of record on the close of business on March 2, 2022. Subsequent to December 31, 2021 and through the date the accompanying financial statements were issued, the Company repurchased 3,388,155 common shares pursuant to the NCIB in effect during that period at an aggregate cost of $425,000. ​

Valuation and Qualifying Accoun

Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2021
Valuation and Qualifying Accounts [Abstract]
Schedule II Valuation and Qualifying Accounts	WASTE CONNECTIONS, INC. SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS Years Ended December 31, 2021, 2020 and 2019 (in thousands of U.S. dollars) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Additions ​ Deductions ​ ​ ​ ​ ​ Balance at ​ Charged to ​ Charged to ​ (Write-offs, ​ ​ ​ ​ ​ Beginning of ​ Costs and ​ Other ​ Net of ​ Balance at End Description Year Expenses Accounts Collections) of Year Allowance for Credit Losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2021 ​ $ 19,380 ​ $ 9,727 ​ $ — ​ $ (10,627) ​ $ 18,480 Year Ended December 31, 2020 ​ $ 16,432 ​ $ 15,546 ​ $ — ​ $ (12,598) ​ $ 19,380 Year Ended December 31, 2019 ​ $ 16,760 ​ $ 11,973 ​ $ — ​ $ (12,301) ​ $ 16,432 ​

New Accounting Standards and _2

New Accounting Standards and Reclassifications (Policies)	12 Months Ended
	Dec. 31, 2021
New Accounting Standards and Reclassifications [Abstract]
Reclassification	Reclassification Cash flow statement information reported in the Company’s prior year periods has been reclassified to conform with the 2021 presentation.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2021
Business [Abstract]
Reporting Currency	Reporting Currency The functional currency of the Company, as the parent corporate entity, and its operating subsidiaries in the United States, is the U.S. dollar. The functional currency of the Company’s Canadian operations is the Canadian dollar. The reporting currency of the Company is the U.S. dollar. The Company’s consolidated Canadian dollar financial position is translated to U.S. dollars by applying the foreign currency exchange rate in effect at the consolidated balance sheet date. The Company’s consolidated Canadian dollar results of operations and cash flows are translated to U.S. dollars by applying the average foreign currency exchange rate in effect during the reporting period. The resulting translation adjustments are included in other comprehensive income or loss. Gains and losses from foreign currency transactions are included in earnings for the period.
Cash Equivalents	Cash Equivalents The Company considers all highly liquid investments with a maturity of three months or less at purchase to be cash equivalents. As of December 31, 2021 and 2020, cash equivalents consisted of demand money market accounts.
Concentrations of Credit Risk	Concentrations of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and equivalents, restricted cash, restricted investments and accounts receivable. The Company maintains cash and equivalents with banks that at times exceed applicable insurance limits. The Company reduces its exposure to credit risk by maintaining such deposits with high quality financial institutions. The Company’s restricted cash and restricted investments are invested primarily in money market accounts, bank time deposits, U.S. government and agency securities and Canadian bankers’ acceptance notes. The Company has not experienced any losses related to its cash and equivalents, restricted cash or restricted investment accounts. The Company generally does not require collateral on its trade receivables. Credit risk on accounts receivable is minimized as a result of the large and diverse nature of the Company’s customer base. The Company maintains allowances for credit losses based on the expected collectability of accounts receivable.
Revenue Recognition	Revenue Recognition and Accounts Receivable The Company’s operations primarily consist of providing non-hazardous waste collection, transfer, disposal and recycling services, E&P services, and intermodal services. The following table disaggregates the Company’s revenues by service line for the periods indicated: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 2020 2019 Commercial $ 1,813,426 ​ $ 1,610,313 $ 1,593,217 Residential ​ ​ 1,673,819 ​ ​ 1,528,217 ​ ​ 1,380,763 Industrial and construction roll off ​ ​ 954,181 ​ ​ 833,148 ​ ​ 841,173 Total collection ​ ​ 4,441,426 ​ ​ 3,971,678 ​ ​ 3,815,153 Landfill ​ ​ 1,233,499 ​ ​ 1,146,732 ​ ​ 1,132,935 Transfer ​ ​ 859,113 ​ ​ 777,754 ​ ​ 771,316 Recycling ​ ​ 205,076 ​ ​ 86,389 ​ ​ 64,245 E&P ​ ​ 138,707 ​ ​ 159,438 ​ ​ 271,887 Intermodal and other ​ ​ 152,194 ​ ​ 118,396 ​ ​ 121,137 Intercompany ​ ​ (878,654) ​ ​ (814,397) ​ ​ (787,994) Total $ 6,151,361 ​ $ 5,445,990 $ 5,388,679 ​ The factors that impact the timing and amount of revenue recognized for each service line may vary based on the nature of the service performed. Generally, the Company recognizes revenue at the time it performs a service. In the event that the Company bills for services in advance of performance, it recognizes deferred revenue for the amount billed and subsequently recognizes revenue at the time the service is provided. See Note 17 for additional information regarding revenue by reportable segment. Revenue by Service Line Solid Waste Collection The Company’s solid waste collection business involves the collection of waste from residential, commercial and industrial customers for transport to transfer stations, or directly to landfills or recycling centers. Solid waste collection services include both recurring and temporary customer relationships. The services are performed under service agreements, municipal contracts or franchise agreements with governmental entities. Existing franchise agreements and most of the existing municipal contracts give the Company the exclusive right to provide specified waste services in the specified territory during the contract term. These exclusive arrangements are awarded, at least initially, on a competitive bid basis and subsequently on a bid or negotiated basis. The standard customer service agreements generally range from one In general, residential collection fees are billed monthly or quarterly in advance. Substantially all of the deferred revenue recorded as of September 30, 2021 was recognized as revenue during the three months ended December 31, 2021 when the service was performed. Commercial customers are typically billed on a monthly basis based on the nature of the services provided during the period. Revenue recognized under these agreements is variable in nature based on the number of residential homes or businesses serviced during the period, the frequency of collection and the volume of waste collected. In addition, certain contracts have annual price escalation clauses that are tied to changes in an underlying base index such as a consumer price index which are unknown at contract inception. Solid waste collection revenue from sources other than customer contracts primarily relates to lease revenue associated with compactors. Revenue from these leasing arrangements was not material and represented an insignificant amount of total revenue for each of the reported periods. Landfill and Transfer Station Revenue at landfills is primarily generated by charging tipping fees on a per ton and/or per yard basis to third parties based on the volume disposed and the nature of the waste. In general, fees are variable in nature and revenue is recognized at the time the waste is disposed at the facility. Revenue at transfer stations is primarily generated by charging tipping or disposal fees on a per ton and/or per yard basis. The fees charged to third parties are based primarily on the market, type and volume or weight of the waste accepted, the distance to the disposal facility and the cost of disposal. In general, fees are billed and revenue is recognized at the time the service is performed. Revenue recognized under these agreements is variable in nature based on the volume of waste accepted at the transfer facility. Many of the Company’s landfill and transfer station customers have entered into one Solid Waste Recycling Solid waste recycling revenues result from the sale of recycled commodities, which are generated by offering residential, commercial, industrial and municipal customers recycling services for a variety of recyclable materials, including compost, cardboard, mixed paper, plastic containers, glass bottles and ferrous and aluminum metals. The Company owns and operates recycling operations and markets collected recyclable materials to third parties for processing before resale. In some instances, the Company utilizes a third party to market recycled materials. In certain instances, the Company issues recycling rebates to municipal or commercial customers, which can be based on the price it receives upon the sale of recycled commodities, a fixed contractual rate or other measures. The Company also receives rebates when it disposes of recycled commodities at third-party facilities. The fees received are based primarily on the market, type and volume or weight of the materials sold. In general, fees are billed and revenue is recognized at the time title is transferred. Revenue recognized under these agreements is variable in nature based on the volume of materials sold. In addition, the amount of revenue recognized is based on commodity prices at the time of sale, which are unknown at contract inception. E&P Waste Treatment, Recovery and Disposal E&P waste revenue is primarily generated through the treatment, recovery and disposal of non-hazardous exploration and production waste from vertical and horizontal drilling, hydraulic fracturing, production and clean-up activity, as well as other services. Revenue recognized under these agreements is variable in nature based on the volume of waste accepted or processed during the period. Intermodal and Other Intermodal revenue is primarily generated through providing intermodal services for the rail haul movement of cargo and solid waste containers in the Pacific Northwest through a network of intermodal facilities. The fees received for intermodal services are based on negotiated rates and vary depending on volume commitments by the shipper and destination. In general, fees are billed and revenue is recognized upon delivery. Other revenues consist primarily of the sale of methane gas and renewable energy credits generated from the Company’s MSW landfills. Revenue Recognition Service obligations of a long-term nature, e.g., solid waste collection service contracts, are satisfied over time, and revenue is recognized based on the value provided to the customer during the period. The amount billed to the customer is based on variable elements such as the number of residential homes or businesses for which collection services are provided, the volume of waste collected, transported and disposed, and the nature of the waste accepted. The Company does not disclose the value of unsatisfied performance obligations for these contracts as its 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. Additionally, certain elements of long-term customer contracts are unknown upon entering into the contract, including the amount that will be billed in accordance with annual price escalation clauses, fuel recovery fee programs and commodity prices. The amount to be billed is often tied to changes in an underlying base index such as a consumer price index or a fuel or commodity index, and revenue is recognized once the index is established for the period.
Accounts Receivable	Accounts Receivable Accounts receivable are recorded when billed or accrued and represent claims against third parties that will be settled in cash. The carrying value of the Company’s receivables, net of the allowance for credit losses, represents their estimated net realizable value. The allowance for credit losses is based on management’s assessment of the collectability of assets pooled together with similar risk characteristics. The Company monitors the collectability of its trade receivables as one overall pool due to all trade receivables having similar risk characteristics. The Company estimates its allowance for credit losses based on historical collection trends, the age of outstanding receivables, geographical location of the customer, existing economic conditions and reasonable forecasts. 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 the Company’s internal collection efforts have been unsuccessful in collecting the amount due. The following is a rollforward of the Company’s allowance for credit losses for the periods indicated: ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2021 2020 Beginning balance ​ $ 19,380 ​ $ 16,432 Current period provision for expected credit losses ​ ​ 9,719 ​ ​ 15,509 Write-offs charged against the allowance ​ ​ (15,545) ​ ​ (18,318) Recoveries collected ​ ​ 4,918 ​ ​ 5,720 Impact of changes in foreign currency ​ ​ 8 ​ ​ 37 Ending balance ​ $ 18,480 ​ $ 19,380
Contract Acquisition Costs	Contract Acquisition Costs The incremental direct costs of obtaining a contract, which consist of sales incentives, are recognized as Other assets in the Company’s Consolidated Balance Sheet, and are amortized to Selling, general and administrative expense over the estimated life of the relevant customer relationship, which ranges from one would have recognized is one year or less. The Company had $18,954 and $19,669 of deferred sales incentives at December 31, 2021 and 2020, respectively. During the years ended December 31, 2021, 2020 and 2019, the Company recorded a total of $23,671, $17,138 and $19,673, respectively, of sales incentive amortization expense for deferred sales incentives and sales incentive expense for contracts with original terms of less than one year.
Property and Equipment	Property and Equipment Property and equipment are stated at cost. Improvements or betterments, not considered to be maintenance and repair, which add new functionality or significantly extend the life of an asset are capitalized. Third-party expenditures related to pending development projects, such as legal and engineering expenses, are capitalized. Expenditures for maintenance and repair costs, including planned major maintenance activities, are charged to expense as incurred. The cost of assets retired or otherwise disposed of and the related accumulated depreciation are eliminated from the accounts in the year of disposal. Gains and losses resulting from disposals of property and equipment are recognized in the period in which the property and equipment is disposed. Depreciation is computed using the straight-line method over the estimated useful lives of the assets or the lease term, whichever is shorter. The estimated useful lives are as follows: ​ ​ ​ ​ Buildings 10 Leasehold and land improvements 3 Machinery and equipment 3 Rolling stock 3 Containers 3
Landfill Accounting	Landfill Accounting The Company utilizes the life cycle method of accounting for landfill costs. This method applies the costs to be capitalized associated with acquiring, developing, closing and monitoring the landfills over the associated consumption of landfill capacity. The Company utilizes the units of consumption method to amortize landfill development costs over the estimated remaining capacity of a landfill. Under this method, the Company includes future estimated construction costs using current dollars, as well as costs incurred to date, in the amortization base. When certain criteria are met, the Company includes expansion airspace, which has not been permitted, in the calculation of the total remaining capacity of the landfill. - Landfill development costs - Final capping, closure and post-closure obligations a landfill facility ceases to accept waste and closes. Accruals for final capping, closure and post-closure monitoring and maintenance requirements in the U.S. consider site inspection, groundwater monitoring, leachate management, methane gas control and recovery, and operating and maintenance costs to be incurred during the period after the facility closes. Certain of these environmental costs, principally capping and methane gas control costs, are also incurred during the operating life of the site in accordance with the landfill operation requirements of Subtitle D and the air emissions standards. Daily maintenance activities, which include many of these costs, are expensed as incurred during the operating life of the landfill. Daily maintenance activities include leachate disposal; surface water, groundwater, and methane gas monitoring and maintenance; other pollution control activities; mowing and fertilizing the landfill final cap; fence and road maintenance; and third-party inspection and reporting costs. Site specific final capping, closure and post-closure engineering cost estimates are prepared annually for landfills owned or landfills operated under life-of-site agreements by the Company. The net present value of landfill final capping, closure and post-closure liabilities are calculated by estimating the total obligation in current dollars, inflating the obligation based upon the expected date of the expenditure and discounting the inflated total to its present value using a credit-adjusted risk-free rate. Any changes in expectations that result in an upward revision to the estimated undiscounted cash flows are treated as a new liability and are inflated and discounted at rates reflecting current market conditions. Any changes in expectations that result in a downward revision (or no revision) to the estimated undiscounted cash flows result in a liability that is inflated and discounted at rates reflecting the market conditions at the time the cash flows were originally estimated. This policy results in the Company’s final capping, closure and post-closure liabilities being recorded in “layers.” The Company’s discount rate assumption for purposes of computing 2021 and 2020 “layers” for final capping, closure and post-closure obligations was 3.25% and 4.75%, respectively, which reflects the Company’s long-term credit adjusted risk free rate. The Company’s inflation rate assumption was 2.25% and 2.50% for the years ended December 31, 2021 and 2020, respectively. In accordance with the accounting guidance on asset retirement obligations, the final capping, closure and post-closure liability is recorded on the balance sheet along with an offsetting addition to site costs which is amortized to depletion expense on a units-of-consumption basis as remaining landfill airspace is consumed. The impact of changes determined to be changes in estimates, based on an annual update, is accounted for on a prospective basis. Depletion expense resulting from final capping, closure and post-closure obligations recorded as a component of landfill site costs will generally be less during the early portion of a landfill’s operating life and increase thereafter. Owned landfills and landfills operated under life-of-site agreements have estimated remaining lives, based on remaining permitted capacity, probable expansion capacity and projected annual disposal volumes, that range from approximately 1 to 282 years, with approximately 90% of the projected annual disposal volume from landfills with remaining lives of less than 70 years. The costs for final capping, closure and post-closure obligations at landfills the Company owns or operates under life-of-site agreements are generally estimated based on interpretations of current requirements and proposed or anticipated regulatory changes. The following is a reconciliation of the Company’s final capping, closure and post-closure liability balance from December 31, 2019 to December 31, 2021: ​ ​ ​ ​ ​ Final capping, closure and post-closure liability at December 31, 2019 $ 291,474 Liability adjustments ​ 2,490 Accretion expense associated with landfill obligations ​ 14,874 Closure payments ​ (6,488) Assumption of closure liabilities from acquisitions ​ 2,136 Disposition of closure liabilities from divested operations ​ ​ (3,413) Foreign currency translation adjustment ​ ​ 823 Final capping, closure and post-closure liability at December 31, 2020 ​ 301,896 Liability adjustments ​ (1,081) Accretion expense associated with landfill obligations ​ 14,333 Closure payments ​ (21,040) Assumption of closure liabilities from acquisitions ​ ​ 11,380 Disposition of closure liabilities from divested operations ​ ​ (3,566) Foreign currency translation adjustment ​ 615 Final capping, closure and post-closure liability at December 31, 2021 ​ $ 302,537 ​ Liability adjustments of $1,081 and $2,490 for the years ended December 31, 2021 and 2020, respectively, represent non-cash changes to final capping, closure and post-closure liabilities and are recorded on the Consolidated Balance Sheets along with an offsetting addition to site costs, which is amortized to depletion expense as the remaining landfill airspace is consumed. The final capping, closure and post-closure liability is included in Other long-term liabilities in the Consolidated Balance Sheets. The Company performs its annual review of its cost and capacity estimates in the first quarter of each year. - Disposal capacity 1) whether the land where the expansion is being sought is contiguous to the current disposal site, and the Company either owns the expansion property or has rights to it under an option, purchase, operating or other similar agreement; 2) whether total development costs, final capping costs, and closure/post-closure costs have been determined; 3) whether internal personnel have performed a financial analysis of the proposed expansion site and have determined that it has a positive financial and operational impact; 4) whether internal personnel or external consultants are actively working to obtain the necessary approvals to obtain the landfill expansion permit; and 5) whether the Company considers it probable that the Company will achieve the expansion (for a pursued expansion to be considered probable, there must be no significant known technical, legal, community, business, or political restrictions or similar issues existing that the Company believes are more likely than not to impair the success of the expansion). It is possible that the Company’s estimates or assumptions could ultimately be significantly different from actual results. In some cases, the Company may be unsuccessful in obtaining an expansion permit or the Company may determine that an expansion permit that the Company previously thought was probable has become unlikely. To the extent that such estimates, or the assumptions used to make those estimates, prove to be significantly different than actual results, or the belief that the Company will receive an expansion permit changes adversely in a significant manner, the costs of the landfill, including the costs incurred in the pursuit of the expansion, may be subject to impairment testing, as described below, and lower profitability may be experienced due to higher amortization rates, higher capping, closure and post-closure rates, and higher expenses or asset impairments related to the removal of previously included expansion airspace. The Company periodically evaluates its landfill sites for potential impairment indicators. The Company’s judgments regarding the existence of impairment indicators are based on regulatory factors, market conditions and operational performance of its landfills. Future events could cause the Company to conclude that impairment indicators exist and that its landfill carrying costs are impaired.
Business Combination Accounting	Business Combination Accounting The Company accounts for business combinations as follows: ● ●
Finite-Lived Intangible Assets	Finite-Lived Intangible Assets The amounts assigned to franchise agreements, contracts, customer lists, permits and other agreements are being amortized over the expected term of the related agreements (ranging from 1
Goodwill and Indefinite-Lived Intangible Assets	Goodwill and Indefinite-Lived Intangible Assets The Company acquired indefinite-lived intangible assets in connection with certain of its acquisitions. The amounts assigned to indefinite-lived intangible assets consist of the value of certain perpetual rights to provide solid waste collection and transportation services in specified territories and to operate E&P waste treatment and disposal facilities. The Company measures and recognizes acquired indefinite-lived intangible assets at their estimated acquisition date fair values. Indefinite-lived intangible assets are not amortized. Goodwill represents the excess of: (a) the aggregate of the fair value of consideration transferred, the fair value of any noncontrolling interest in the acquiree (if any) and the acquisition date fair value of the Company’s previously held equity interest in the acquiree (if any), over (b) the fair value of assets acquired and liabilities assumed. Goodwill and intangible assets, deemed to have indefinite lives, are subject to annual impairment tests as described below. Goodwill and indefinite-lived intangible assets are tested for impairment on at least an annual basis in the fourth quarter of the year. In addition, the Company evaluates its reporting units for impairment if events or circumstances change between annual tests indicating a possible impairment. Examples of such events or circumstances include, but are not limited to, the following: ● ● ● ● ● As part of the Company’s goodwill impairment test, the Company estimates the fair value of each of its reporting units using discounted cash flow analyses. At December 31, 2019, the Company’s reporting units consisted of its five geographic solid waste operating segments and its E&P segment. As of July 1, 2020, the Company combined all operations of its E&P segment into the Southern segment, based on the Company’s determination that the two operating segments met the aggregation criteria, and eliminated the E&P segment. The Company’s former E&P segment had $0 of goodwill at each of December 31, 2020 and December 31, 2019. The Company compares the fair value of each reporting unit with the carrying value of the net assets assigned to each reporting unit. If the fair value of a reporting unit is greater than the carrying value of the net assets, including goodwill, assigned to the reporting unit, then no impairment results. If the fair value is less than its carrying value, an impairment charge is recorded for the amount by which the carrying value exceeds its fair value, not to exceed the carrying amount of goodwill. In testing indefinite-lived intangible assets for impairment, the Company compares the estimated fair value of each indefinite-lived intangible asset to its carrying value. If the fair value of the indefinite-lived intangible asset is less than its carrying value, an impairment charge would be recorded to earnings in the Company’s Consolidated Statements of Net Income. During the Company’s annual impairment analysis of its solid waste operations, the Company determined the fair value of each of its five geographic operating segments at December 31, 2021, 2020 and 2019 and each indefinite-lived intangible asset within those segments using discounted cash flow analyses, which require significant assumptions and estimates about the future operations of each reporting unit and the future discrete cash flows related to each indefinite-lived intangible asset. Significant judgments inherent in these analyses include the determination of appropriate discount rates, the amount and timing of expected future cash flows, growth rates and income tax rates. The cash flows employed in the Company’s 2021 discounted cash flow analyses were based on ten-year financial forecasts, which in turn were based on the 2022 annual budget developed internally by management. These forecasts reflect operating profit margins that were consistent with 2021 results and perpetual revenue growth rates of 4.5%. The Company’s discount rate assumptions are based on an assessment of the market participant rate which approximated 6.1%. In assessing the reasonableness of the Company’s determined fair values of its reporting units, the Company evaluates its results against its current market capitalization. The Company did not record an impairment charge to any of its five geographic operating segments as a result of its annual goodwill impairment tests for the years ended December 31, 2021, 2020 or 2019. During the fourth quarter of 2021, the Company recorded an impairment charge of $2,277, which is included in Impairments and other operating items in the Consolidated Statements of Net Income, on certain indefinite-lived intangible assets at two of its E&P sites in its Southern segment. The Company did not record an impairment charge to any of its five geographic operating segments as a result of its indefinite-lived intangible assets impairment tests for the years ended December 31, 2020 or 2019.
Impairments of Property and Equipment and Finite-Lived Intangible Assets	Impairments of Property and Equipment and Finite-Lived Intangible Assets Property, equipment and finite-lived intangible assets are carried on the Company’s consolidated financial statements based on their cost less accumulated depreciation or amortization. Finite-lived intangible assets consist of long-term franchise agreements, contracts, customer lists, permits and other agreements. The recoverability of these assets is tested whenever events or changes in circumstances indicate that their carrying amount may not be recoverable. Typical indicators that an asset may be impaired include, but are not limited to, the following: ● ● ● ● ● If any of these or other indicators occur, a test of recoverability is performed by comparing the carrying value of the asset or asset group to its undiscounted expected future cash flows. If the carrying value is in excess of the undiscounted expected future cash flows, impairment is measured by comparing the fair value of the asset to its carrying value. Fair value is determined by an internally developed discounted projected cash flow analysis of the asset. Cash flow projections are sometimes based on a group of assets, rather than a single asset. If cash flows cannot be separately and independently identified for a single asset, the Company will determine whether an impairment has occurred for the group of assets for which the projected cash flows can be identified. If the fair value of an asset is determined to be less than the carrying amount of the asset or asset group, an impairment in the amount of the difference is recorded in the period that the impairment indicator occurs. Several impairment indicators are beyond the Company’s control, and whether or not they will occur cannot be predicted with any certainty. Estimating future cash flows requires significant judgment and projections may vary from cash flows eventually realized. There are other considerations for impairments of landfills, as described below. During the year ended December 31, 2021, the Company recorded a $16,379 impairment charge, which is included in Impairments and other operating items in the Consolidated Statements of Net Income, for property and equipment and definite-lived intangible assets at three of its E&P waste sites in its Southern segment. The demand for the Company’s E&P waste services depends on the continued demand for, and production of, oil and natural gas. Crude oil and natural gas prices historically have been volatile. Macroeconomic and geopolitical conditions, including a significant decline in oil prices occurring in 2020 driven by both surplus production and supply, as well as the decrease in demand caused by factors including the COVID-19 pandemic, resulted in decreased levels of oil and natural gas exploration and production activity and a corresponding decrease in demand for the Company’s E&P waste services in 2020. During the year ended December 31, 2020, total E&P waste revenue declined $112,114, compared to the prior year period, on rig count declines of 56% in certain basins. The most impacted basins include the Williston Basin in North Dakota, the Eagle Ford Basin in Texas and the Powder River Basin in Wyoming, all of which have relatively high costs associated with drilling, making them less attractive than other basins, including the Permian Basin in Texas and New Mexico. Additionally, across the industry there was uncertainty regarding future demand for oil and related services, as noted by several energy companies during 2020, many of whom are customers of the Company’s E&P waste operations. These companies wrote down the values of their oil and gas assets in anticipation of the potential for the decarbonization of their energy product mix given an increased global focus on reducing greenhouse gases and addressing climate change. Such uncertainty regarding global demand had a significant impact on the investment and operating plans of the Company’s E&P waste customers in the basins where the Company operates. The decrease in E&P activity, together with market expectations of a likely slow recovery in oil prices, reduced the expected future period cash flows of the Company’s E&P waste operations. Based on these events, the Company concluded that a triggering event occurred which required the Company to perform an impairment test of the property and equipment and intangible assets of its E&P waste operations as of June 30, 2020 using July 2020 industry projections for drilling activity by basin as the basis for expectations about future activity. Based upon the results of the impairment test, the Company concluded that the carrying value exceeded the projected undiscounted cash flows of four E&P waste landfills. The next step was to calculate the fair value of these four landfills using an income approach employing a discounted cash flow (“DCF”) model over the lesser of 40 years or the remaining life of each landfill. Additional key assumptions used in the DCF model included a discount rate of 12% applied to the cash flows, annual revenue projections based on E&P waste resulting from projected levels of oil and natural gas E&P activity during the forecast period at each location, gross margins based on estimated operating expense requirements during the forecast period, estimated capital expenditures over the forecast period and income taxes based on the estimated federal and state income tax rates applicable during the cash flow periods, all of which were classified as Level 3 in the fair value hierarchy. For each of the four landfills, the carrying value exceeded the calculated discounted fair value, resulting in the recording of an impairment charge of $417,384 to Impairments and other operating items in the Consolidated Statements of Net Income during the year ended December 31, 2020. The four landfills had $0 of intangible assets at June 30, 2020; therefore, no impairment charge was attributable to intangible assets. The impairment charge reduced the carrying value of property and equipment by $417,384. If the estimated annual cash flows in the DCF model for each asset or asset group tested was changed by 10%, the resulting impairment charge would change by approximately $3,000. The aforementioned impairment charges were partially offset by a $4,145 adjustment, also recorded during the year ended December 31, 2020, to reduce the fair value of an amount payable in 2022 under a liability-classified contingent consideration arrangement calculated on future earnings and cash flows associated with the acquisition of an E&P business in 2014. During the year ended December 31, 2019, the Company recorded an $8,000 impairment charge, which is included in Impairments and other operating items in the Consolidated Statements of Net Income, for property and equipment associated with a landfill development project in its E&P segment that the Company is no longer pursuing. There are certain indicators listed above that require significant judgment and understanding of the waste industry when applied to landfill development or expansion projects. A regulator or court may deny or overturn a landfill development or landfill expansion permit application before the development or expansion permit is ultimately granted. Management may periodically divert waste from one landfill to another to conserve remaining permitted landfill airspace. Therefore, certain events could occur in the ordinary course of business and not necessarily be considered indicators of impairment due to the unique nature of the waste industry.
Restricted Cash and Restricted Investments	Restricted Cash and Restricted Investments Restricted cash and restricted investments consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021 ​ December 31, 2020 ​ ​ Restricted ​ Restricted ​ Restricted ​ Restricted ​ Cash Investments Cash Investments Settlement of insurance claims ​ $ 52,906 ​ $ — ​ $ 78,335 ​ $ — Landfill closure and post-closure obligations ​ ​ 12,609 ​ ​ 56,289 ​ ​ 12,533 ​ ​ 54,833 Other financial assurance requirements ​ ​ 6,659 ​ ​ 2,725 ​ ​ 6,227 ​ ​ 2,683 ​ ​ $ 72,174 ​ $ 59,014 ​ $ 97,095 ​ $ 57,516 ​ See Note 12 for further information on restricted cash and restricted investments.
Fair Value of Financial Instruments	Fair Value of Financial Instruments The Company’s financial instruments consist primarily of cash and equivalents, trade receivables, restricted cash and investments, trade payables, debt instruments, contingent consideration obligations and interest rate swaps. As of December 31, 2021 and 2020, the carrying values of cash and equivalents, trade receivables, restricted cash and investments, trade payables and contingent consideration are considered to be representative of their respective fair values. The carrying values of the Company’s debt instruments, excluding certain notes as listed in the table below, approximate their fair values as of December 31, 2021 and 2020, based on current borrowing rates, current remaining average life to maturity and borrower credit quality for similar types of borrowing arrangements, and are classified as Level 2 within the fair value hierarchy. The carrying values and fair values of the Company’s debt instruments where the carrying values do not approximate their fair values as of December 31, 2021 and 2020, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Carrying Value at ​ Fair Value (a) at ​ ​ December 31, ​ December 31, ​ December 31, ​ December 31, ​ 2021 2020 2021 2020 4.64% Senior Notes due 2021 ​ $ — ​ $ 100,000 ​ $ — ​ $ 100,850 2.39% Senior Notes due 2021 ​ $ — ​ $ 150,000 ​ $ — ​ $ 150,695 3.09% Senior Notes due 2022 (b) ​ $ — ​ $ 125,000 ​ $ — ​ $ 128,482 2.75% Senior Notes due 2023 (b) ​ $ — ​ $ 200,000 ​ $ — ​ $ 206,204 3.24% Senior Notes due 2024 (b) ​ $ — ​ $ 150,000 ​ $ — ​ $ 158,140 3.41% Senior Notes due 2025 (b) ​ $ — ​ $ 375,000 ​ $ — ​ $ 403,025 3.03% Senior Notes due 2026 (b) ​ $ — ​ $ 400,000 ​ $ — ​ $ 424,874 3.49% Senior Notes due 2027 (b) ​ $ — ​ $ 250,000 ​ $ — ​ $ 271,198 4.25% Senior Notes due 2028 ​ $ 500,000 ​ $ 500,000 ​ $ 561,350 ​ $ 597,050 3.50% Senior Notes due 2029 ​ $ 500,000 ​ $ 500,000 ​ $ 539,500 ​ $ 570,450 2.60% Senior Notes due 2030 ​ $ 600,000 ​ $ 600,000 ​ $ 610,440 ​ $ 644,520 2.20% Senior Notes due 2032 ​ $ 650,000 ​ $ — ​ $ 637,065 ​ $ — 3.05% Senior Notes due 2050 ​ $ 500,000 ​ $ 500,000 ​ $ 496,350 ​ $ 540,050 2.95% Senior Notes due 2052 ​ $ 850,000 ​ $ — ​ $ 828,580 ​ $ — (a) Senior Notes are classified as Level 2 within the fair value hierarchy. Fair value inputs include third-party calculations of the market interest rate of notes with similar ratings in similar industries over the remaining note terms. (b) All of the outstanding Senior Notes issued pursuant to the 2008 and 2016 master note purchase agreements were redeemed by the Company on September 20, 2021. For details on the fair value of the Company’s interest rate swaps, restricted cash and investments and contingent consideration, see Note 12.
Derivative Financial Instruments	Derivative Financial Instruments The Company recognizes all derivatives on the balance sheet at fair value. All of the Company’s derivatives have been designated as cash flow hedges; therefore, the gain or loss on the derivatives will be recognized in accumulated other comprehensive income (loss) (“AOCIL”) and reclassified into earnings in the same period during which the hedged transaction affects earnings and is presented in the same income statement line item as the earnings effect of the hedged item. The Company classifies cash inflows and outflows from derivatives within operating activities on the statement of cash flows. One of the Company’s objectives for utilizing derivative instruments is to reduce its exposure to fluctuations in cash flows due to changes in the variable interest rates of certain borrowings under the Credit Agreement (defined below). The Company’s strategy to achieve that objective involves entering into interest rate swaps. The interest rate swaps outstanding at December 31, 2021 were specifically designated to the Credit Agreement and accounted for as cash flow hedges. At December 31, 2021, the Company’s derivative instruments included six interest rate swap agreements as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fixed Variable ​ ​ ​ ​ Notional ​ Interest ​ Interest Rate ​ ​ ​ Expiration Date Entered ​ Amount ​ Rate Paid* ​ Received ​ Effective Date ​ Date August 2017 ​ $ 100,000 1.900 % 1-month LIBOR July 2019 July 2022 August 2017 ​ $ 200,000 2.200 % 1-month LIBOR October 2020 October 2025 August 2017 ​ $ 150,000 1.950 % 1-month LIBOR February 2020 February 2023 June 2018 ​ $ 200,000 ​ 2.925 % 1-month LIBOR ​ October 2020 ​ October 2025 June 2018 ​ $ 200,000 ​ 2.925 % 1-month LIBOR ​ October 2020 ​ October 2025 December 2018 ​ $ 200,000 ​ 2.850 % 1-month LIBOR ​ July 2022 ​ July 2027 * Plus applicable margin. On September 28, 2020, the Company terminated four of its interest rate swaps with notional amounts of $150,000, $150,000, $50,000 and $50,000, each of which would have expired in January 2021. As a result of terminating these interest rate swaps, the Company made total cash payments of $853 to the counterparties of the swap agreements. The fair values of derivative instruments designated as cash flow hedges as of December 31, 2021, were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivatives Designated as Cash ​ Asset Derivatives ​ Liability Derivatives Flow Hedges Balance Sheet Location Fair Value Balance Sheet Location Fair Value Interest rate swaps Prepaid expenses and other current assets ​ $ — Accrued liabilities (a) ​ $ (18,675) ​ ​ ​ ​ Other long-term liabilities ​ ​ (32,406) Total derivatives designated as cash flow hedges ​ ​ ​ $ — ​ ​ ​ $ (51,081) (a) Represents the estimated amount of the existing unrealized losses on interest rate swaps as of December 31, 2021 (based on the interest rate yield curve at that date), included in AOCIL expected to be reclassified into pre-tax earnings within the next 12 months. The actual amounts reclassified into earnings are dependent on future movements in interest rates. The fair values of derivative instruments designated as cash flow hedges as of December 31, 2020, were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivatives Designated as Cash ​ Asset Derivatives ​ Liability Derivatives Flow Hedges Balance Sheet Location Fair Value Balance Sheet Location Fair Value Interest rate swaps Prepaid expenses and other current assets ​ $ — Accrued liabilities ​ $ (20,023) ​ ​ ​ ​ Other long-term liabilities ​ (74,666) Total derivatives designated as cash flow hedges ​ ​ ​ $ — ​ ​ ​ $ (94,689) ​ The following table summarizes the impact of the Company’s cash flow hedges on the results of operations, comprehensive income (loss) and AOCIL for the years ended December 31, 2021, 2020 and 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivatives ​ ​ ​ Statement of ​ Amount of (Gain) or Loss Reclassified Designated as Cash ​ Amount of Gain or (Loss) Recognized ​ Net Income ​ from AOCIL into Earnings, Flow Hedges ​ as AOCIL on Derivatives, Net of Tax (a) ​ Classification ​ Net of Tax (b) ​ ​ Years Ended December 31, ​ ​ ​ Years Ended December 31, ​ 2021 2020 2019 ​ 2021 2020 2019 Interest rate swaps ​ $ 17,116 ​ $ (47,528) ​ $ (32,247) ​ Interest expense ​ $ 14,936 ​ $ 7,187 ​ $ (5,900) (a) In accordance with the derivatives and hedging guidance, the changes in fair values of interest rate swaps have been recorded in equity as a component of AOCIL. As the critical terms of the interest rate swaps match the underlying debt being hedged, all unrealized changes in fair value are recorded in AOCIL. (b) Amounts reclassified from AOCIL into earnings related to realized gains and losses on interest rate swaps are recognized when interest payments or receipts occur related to the swap contracts, which correspond to when interest payments are made on the Company’s hedged debt. See Note 15 for further discussion on the impact of the Company’s hedge accounting to its consolidated comprehensive income (loss) and AOCIL.
Income Taxes	Income Taxes Deferred tax assets and liabilities are determined based on differences between the financial reporting and income tax bases of assets and liabilities and are measured using the enacted tax rates and laws that are expected to be in effect when the differences are expected to reverse. The Company records valuation allowances to reduce net deferred tax assets to the amount considered more likely than not to be realized. The Company is required to evaluate whether the tax positions taken on its income tax returns will more likely than not be sustained upon examination by the appropriate taxing authority. If the Company determines that such tax positions will not be sustained, it records a liability for the related unrecognized tax benefits. The Company classifies its liability for unrecognized tax benefits as a current liability to the extent it anticipates making a payment within one year.
Share-Based Compensation	Share-Based Compensation Under the 2020 Employee Share Purchase Plan (the “ESPP”), participants will be granted an option to purchase Company common shares on the first business day of each offering period, with such option to be automatically exercised on the last business day of such offering period to purchase a whole number of the Company’s common shares determined by dividing the accumulated payroll deductions in the participant’s notional account on such exercise date by the applicable exercise price. The exercise price is equal to 95% of the closing price of the Company’s common shares on the last day of the relevant offering period; provided, however, that such exercise price will not be less than 85% of the volume weighted average price of the Company’s common shares as reflected on the Toronto Stock Exchange (the “TSX”) over the final five trading days of the offering period. The fair value of restricted share unit (“RSU”) awards is determined based on the number of RSUs granted and the closing price of the common shares in the capital of the Company adjusted for future dividends. The fair value of deferred share unit (“DSU”) awards is determined based on the number of DSUs granted and the closing price of the common shares in the capital of the Company. Compensation expense associated with outstanding performance-based restricted share unit (“PSU”) awards is measured using the fair value of the Company’s common shares adjusted for future dividends and is based on the estimated achievement of the established performance criteria at the end of each reporting period until the performance period ends, recognized ratably over the performance period. Compensation expense is only recognized for those awards that the Company expects to vest, which it estimates based upon an assessment of the probability that the performance criteria will be achieved. All share-based compensation cost is measured at the grant date, based on the estimated fair value of the award adjusted for future dividends, and is recognized on a straight-line basis as expense over the employee’s requisite service period. The Company recognizes gross share compensation expense with actual forfeitures as they occur. Warrants are valued using the Black-Scholes pricing model with a contractual life of five years, a risk free interest rate based on the 5-year U.S. treasury yield curve and expected volatility. The Company uses the historical volatility of its common shares over a period equivalent to the contractual life of the warrants to estimate the expected volatility. The fair market value of warrants issued to consultants for acquisitions are recorded immediately as share-based compensation expense. Share-based compensation expense recognized during the years ended December 31, 2021, 2020 and 2019, was $58,221 ($43,495 net of taxes), $45,751 ($34,197 net of taxes) and $42,671 ($31,926 net of taxes), respectively. This share-based compensation expense includes RSUs, PSUs, DSUs, share option and warrant expense. The share-based compensation expense totals include amounts associated with the Progressive Waste share-based compensation plans, continued by the Company following the Progressive Waste acquisition, which allow for the issuance of shares or cash settlement to employees upon vesting. The Company records share-based compensation expense in Selling, general and administrative expenses in the Consolidated Statements of Net Income. The total unrecognized compensation cost at December 31, 2021, related to unvested RSU awards was $57,822 and this future expense will be recognized over the remaining vesting period of the RSU awards, which extends to 2026. The weighted average remaining vesting period of the RSU awards is 1.4 years. The total unrecognized compensation cost at December 31, 2021, related to unvested PSU awards was $20,621 and this future expense will be recognized over the remaining vesting period of the PSU awards, which extends to 2024. The weighted average remaining vesting period of PSU awards is 1.1 years. Other Restricted Share Units As of December 31, 2021, 2020 and 2019, the Company had a liability of $9,008, $7,237 and $7,178, respectively, representing the December 31, 2021, 2020 and 2019 fair values, respectively, of outstanding Progressive Waste restricted share units which are expected to be cash settled. For the years ended December 31, 2021, 2020 and 2019, the fair value was calculated using the number of shares granted and the closing price of the common shares in the capital of the Company. All remaining unvested Progressive Waste restricted share units vested during the year ended December 31, 2019. Other Share Based Options The fair value of the Progressive Waste share based options outstanding was calculated using a Black-Scholes pricing model with the following weighted average assumptions for the years ended December 31, 2021, 2020 and 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2021 ​ 2020 ​ 2019 Expected remaining life 1.00 year ​ 0.50 to 1.00 year ​ 1.50 years Share volatility 15.04% ​ 17.72% to 33.54% ​ 16.14% Discount rate 0.41% ​ 0.06% to 0.12% ​ 1.61% Annual dividend rate 0.68% ​ 0.80% ​ 0.82% ​ All remaining unvested Progressive Waste share based options vested during the year ended December 31, 2017. As of December 31, 2021, 2020 and 2019, the Company had a liability of $4,088, $3,556 and $8,559, respectively, representing the December 31, 2021, 2020 and 2019 fair value, respectively, of outstanding Progressive Waste share based options which are expected to be cash settled.
Per Share Information	Per Share Information Basic net income per share attributable to holders of the Company’s common shares is computed using the weighted average number of common shares outstanding and vested and unissued restricted share units deferred for issuance into the deferred compensation plan. Diluted net income per share attributable to holders of the Company’s common shares is computed using the weighted average number of common and potential common shares outstanding. Potential common shares are excluded from the computation if their effect is anti-dilutive.
Advertising Costs	Advertising Costs Advertising costs are expensed as incurred. Advertising expense for the years ended December 31, 2021, 2020 and 2019, was $7,155, $4,870 and $5,410, respectively, which is included in Selling, general and administrative expense in the Consolidated Statements of Net Income.
Insurance Liabilities	Insurance Liabilities As a result of its insurance policies, the Company is effectively self-insured for automobile liability, general liability, employer’s liability, environmental liability, cyber liability, employment practices liability, and directors’ and officers’ liability as well as for employee group health insurance, property and workers’ compensation. The Company’s insurance accruals are based on claims filed and estimates of claims incurred but not reported and are developed by the Company’s management with assistance from its third-party actuary and its third-party claims administrator. The insurance accruals are influenced by the Company’s past claims experience factors and by published industry development factors. At December 31, 2021 and 2020, the Company’s total accrual for self-insured liabilities was $147,757 and $140,182, respectively, which is included in Accrued liabilities in the Consolidated Balance Sheets. For the years ended December 31, 2021, 2020 and 2019, the Company recognized $179,250, $164,099 and $155,748, respectively, of self-insurance expense which is included in Cost of operations and Selling, general and administrative expense in the Consolidated Statements of Net Income.

Leases (Policy)

Leases (Policy)	12 Months Ended
	Dec. 31, 2021
Lessee Disclosure [Abstract]
Leases	The Company rents certain equipment and facilities under short-term agreements, non-cancelable operating lease agreements and finance leases. The Company determines if an arrangement is or contains a lease at contract inception. The Company recognizes a right-of-use (“ROU”) asset and a lease liability at the lease commencement date. The lease liability is initially measured at the present value of the unpaid lease payments at the lease commencement date. Key estimates and judgments include how the Company determines (1) the discount rate it uses to discount the unpaid lease payments to present value, (2) lease term and (3) lease payments. The lease guidance requires a lessee to discount its unpaid lease payments using the interest rate implicit in the lease or, if that rate cannot be readily determined, its incremental borrowing rate. Generally, the Company cannot determine the interest rate implicit in the lease because it does not have access to the lessor’s estimated residual value or the amount of the lessor’s deferred initial direct costs. Therefore, the Company generally uses its incremental borrowing rate as the discount rate for the lease. The Company’s incremental borrowing rate for a lease is the rate of interest it would have to pay on a collateralized basis to borrow an amount equal to the lease payments under similar terms. The lease term for the Company’s leases includes the noncancelable period of the lease, plus any additional periods covered by either a Company option to extend (or not to terminate) the lease that the Company is reasonably certain to exercise, or an option to extend (or not to terminate) the lease controlled by the lessor. Lease payments included in the measurement of the lease liability comprise fixed payments or variable lease payments. The variable lease payments take into account annual changes in the consumer price index and common area maintenance charges, if known. ROU assets for operating and finance leases are periodically reviewed for impairment losses. The Company uses the long-lived asset impairment guidance in ASC Subtopic 360-10, Property, Plant, and Equipment – Overall, to determine whether an ROU asset is impaired, and if so, the amount of the impairment loss to recognize. The Company did not recognize an impairment charge for any of its ROU assets during the years ended December 31, 2021, 2020 and 2019. The Company monitors for events or changes in circumstances that require a reassessment of one of its leases. When a reassessment results in the remeasurement of a lease liability, a corresponding adjustment is made to the carrying amount of the corresponding ROU asset. The Company did not recognize any significant remeasurements during the years ended December 31, 2021, 2020 and 2019. The Company has elected not to recognize ROU assets and lease liabilities for short-term leases that have a lease term of 12 months or less. The Company has elected to apply the short-term lease recognition and measurement exemption allowed for in the lease accounting standard. The Company recognizes the lease payments associated with its short-term leases as an expense on a straight-line basis over the lease term.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total Reported Revenues by Service Line	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 2020 2019 Commercial $ 1,813,426 ​ $ 1,610,313 $ 1,593,217 Residential ​ ​ 1,673,819 ​ ​ 1,528,217 ​ ​ 1,380,763 Industrial and construction roll off ​ ​ 954,181 ​ ​ 833,148 ​ ​ 841,173 Total collection ​ ​ 4,441,426 ​ ​ 3,971,678 ​ ​ 3,815,153 Landfill ​ ​ 1,233,499 ​ ​ 1,146,732 ​ ​ 1,132,935 Transfer ​ ​ 859,113 ​ ​ 777,754 ​ ​ 771,316 Recycling ​ ​ 205,076 ​ ​ 86,389 ​ ​ 64,245 E&P ​ ​ 138,707 ​ ​ 159,438 ​ ​ 271,887 Intermodal and other ​ ​ 152,194 ​ ​ 118,396 ​ ​ 121,137 Intercompany ​ ​ (878,654) ​ ​ (814,397) ​ ​ (787,994) Total $ 6,151,361 ​ $ 5,445,990 $ 5,388,679
Allowance for Credit Losses	The following is a rollforward of the Company’s allowance for credit losses for the periods indicated: ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2021 2020 Beginning balance ​ $ 19,380 ​ $ 16,432 Current period provision for expected credit losses ​ ​ 9,719 ​ ​ 15,509 Write-offs charged against the allowance ​ ​ (15,545) ​ ​ (18,318) Recoveries collected ​ ​ 4,918 ​ ​ 5,720 Impact of changes in foreign currency ​ ​ 8 ​ ​ 37 Ending balance ​ $ 18,480 ​ $ 19,380
Property Plant and Equipment Estimated Useful Lives	The estimated useful lives are as follows: ​ ​ ​ ​ Buildings 10 Leasehold and land improvements 3 Machinery and equipment 3 Rolling stock 3 Containers 3
Reconciliation of Final Capping, Closure and Post-Closure Liability Balance	The following is a reconciliation of the Company’s final capping, closure and post-closure liability balance from December 31, 2019 to December 31, 2021: ​ ​ ​ ​ ​ Final capping, closure and post-closure liability at December 31, 2019 $ 291,474 Liability adjustments ​ 2,490 Accretion expense associated with landfill obligations ​ 14,874 Closure payments ​ (6,488) Assumption of closure liabilities from acquisitions ​ 2,136 Disposition of closure liabilities from divested operations ​ ​ (3,413) Foreign currency translation adjustment ​ ​ 823 Final capping, closure and post-closure liability at December 31, 2020 ​ 301,896 Liability adjustments ​ (1,081) Accretion expense associated with landfill obligations ​ 14,333 Closure payments ​ (21,040) Assumption of closure liabilities from acquisitions ​ ​ 11,380 Disposition of closure liabilities from divested operations ​ ​ (3,566) Foreign currency translation adjustment ​ 615 Final capping, closure and post-closure liability at December 31, 2021 ​ $ 302,537
Restricted Cash and Restricted Investments	Restricted cash and restricted investments consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021 ​ December 31, 2020 ​ ​ Restricted ​ Restricted ​ Restricted ​ Restricted ​ Cash Investments Cash Investments Settlement of insurance claims ​ $ 52,906 ​ $ — ​ $ 78,335 ​ $ — Landfill closure and post-closure obligations ​ ​ 12,609 ​ ​ 56,289 ​ ​ 12,533 ​ ​ 54,833 Other financial assurance requirements ​ ​ 6,659 ​ ​ 2,725 ​ ​ 6,227 ​ ​ 2,683 ​ ​ $ 72,174 ​ $ 59,014 ​ $ 97,095 ​ $ 57,516
Carrying Values and Fair Values of Debt Instruments	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Carrying Value at ​ Fair Value (a) at ​ ​ December 31, ​ December 31, ​ December 31, ​ December 31, ​ 2021 2020 2021 2020 4.64% Senior Notes due 2021 ​ $ — ​ $ 100,000 ​ $ — ​ $ 100,850 2.39% Senior Notes due 2021 ​ $ — ​ $ 150,000 ​ $ — ​ $ 150,695 3.09% Senior Notes due 2022 (b) ​ $ — ​ $ 125,000 ​ $ — ​ $ 128,482 2.75% Senior Notes due 2023 (b) ​ $ — ​ $ 200,000 ​ $ — ​ $ 206,204 3.24% Senior Notes due 2024 (b) ​ $ — ​ $ 150,000 ​ $ — ​ $ 158,140 3.41% Senior Notes due 2025 (b) ​ $ — ​ $ 375,000 ​ $ — ​ $ 403,025 3.03% Senior Notes due 2026 (b) ​ $ — ​ $ 400,000 ​ $ — ​ $ 424,874 3.49% Senior Notes due 2027 (b) ​ $ — ​ $ 250,000 ​ $ — ​ $ 271,198 4.25% Senior Notes due 2028 ​ $ 500,000 ​ $ 500,000 ​ $ 561,350 ​ $ 597,050 3.50% Senior Notes due 2029 ​ $ 500,000 ​ $ 500,000 ​ $ 539,500 ​ $ 570,450 2.60% Senior Notes due 2030 ​ $ 600,000 ​ $ 600,000 ​ $ 610,440 ​ $ 644,520 2.20% Senior Notes due 2032 ​ $ 650,000 ​ $ — ​ $ 637,065 ​ $ — 3.05% Senior Notes due 2050 ​ $ 500,000 ​ $ 500,000 ​ $ 496,350 ​ $ 540,050 2.95% Senior Notes due 2052 ​ $ 850,000 ​ $ — ​ $ 828,580 ​ $ — (a) Senior Notes are classified as Level 2 within the fair value hierarchy. Fair value inputs include third-party calculations of the market interest rate of notes with similar ratings in similar industries over the remaining note terms. (b) All of the outstanding Senior Notes issued pursuant to the 2008 and 2016 master note purchase agreements were redeemed by the Company on September 20, 2021.
Fair Value of Derivative Instrument Designated as Cash Flow Hedges	The fair values of derivative instruments designated as cash flow hedges as of December 31, 2021, were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivatives Designated as Cash ​ Asset Derivatives ​ Liability Derivatives Flow Hedges Balance Sheet Location Fair Value Balance Sheet Location Fair Value Interest rate swaps Prepaid expenses and other current assets ​ $ — Accrued liabilities (a) ​ $ (18,675) ​ ​ ​ ​ Other long-term liabilities ​ ​ (32,406) Total derivatives designated as cash flow hedges ​ ​ ​ $ — ​ ​ ​ $ (51,081) (a) Represents the estimated amount of the existing unrealized losses on interest rate swaps as of December 31, 2021 (based on the interest rate yield curve at that date), included in AOCIL expected to be reclassified into pre-tax earnings within the next 12 months. The actual amounts reclassified into earnings are dependent on future movements in interest rates. The fair values of derivative instruments designated as cash flow hedges as of December 31, 2020, were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivatives Designated as Cash ​ Asset Derivatives ​ Liability Derivatives Flow Hedges Balance Sheet Location Fair Value Balance Sheet Location Fair Value Interest rate swaps Prepaid expenses and other current assets ​ $ — Accrued liabilities ​ $ (20,023) ​ ​ ​ ​ Other long-term liabilities ​ (74,666) Total derivatives designated as cash flow hedges ​ ​ ​ $ — ​ ​ ​ $ (94,689)
Impact of Cash Flow Hedges on Results of Operations, Comprehensive Income and Accumulated Other Comprehensive Loss	The following table summarizes the impact of the Company’s cash flow hedges on the results of operations, comprehensive income (loss) and AOCIL for the years ended December 31, 2021, 2020 and 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivatives ​ ​ ​ Statement of ​ Amount of (Gain) or Loss Reclassified Designated as Cash ​ Amount of Gain or (Loss) Recognized ​ Net Income ​ from AOCIL into Earnings, Flow Hedges ​ as AOCIL on Derivatives, Net of Tax (a) ​ Classification ​ Net of Tax (b) ​ ​ Years Ended December 31, ​ ​ ​ Years Ended December 31, ​ 2021 2020 2019 ​ 2021 2020 2019 Interest rate swaps ​ $ 17,116 ​ $ (47,528) ​ $ (32,247) ​ Interest expense ​ $ 14,936 ​ $ 7,187 ​ $ (5,900) (a) In accordance with the derivatives and hedging guidance, the changes in fair values of interest rate swaps have been recorded in equity as a component of AOCIL. As the critical terms of the interest rate swaps match the underlying debt being hedged, all unrealized changes in fair value are recorded in AOCIL. (b) Amounts reclassified from AOCIL into earnings related to realized gains and losses on interest rate swaps are recognized when interest payments or receipts occur related to the swap contracts, which correspond to when interest payments are made on the Company’s hedged debt.
Interest Rate Swap [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Company's Derivative Instruments	At December 31, 2021, the Company’s derivative instruments included six interest rate swap agreements as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fixed Variable ​ ​ ​ ​ Notional ​ Interest ​ Interest Rate ​ ​ ​ Expiration Date Entered ​ Amount ​ Rate Paid* ​ Received ​ Effective Date ​ Date August 2017 ​ $ 100,000 1.900 % 1-month LIBOR July 2019 July 2022 August 2017 ​ $ 200,000 2.200 % 1-month LIBOR October 2020 October 2025 August 2017 ​ $ 150,000 1.950 % 1-month LIBOR February 2020 February 2023 June 2018 ​ $ 200,000 ​ 2.925 % 1-month LIBOR ​ October 2020 ​ October 2025 June 2018 ​ $ 200,000 ​ 2.925 % 1-month LIBOR ​ October 2020 ​ October 2025 December 2018 ​ $ 200,000 ​ 2.850 % 1-month LIBOR ​ July 2022 ​ July 2027 * Plus applicable margin.
Employee Stock Option [Member] | Progressive Waste Plans [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair Value Assumptions	The fair value of the Progressive Waste share based options outstanding was calculated using a Black-Scholes pricing model with the following weighted average assumptions for the years ended December 31, 2021, 2020 and 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2021 ​ 2020 ​ 2019 Expected remaining life 1.00 year ​ 0.50 to 1.00 year ​ 1.50 years Share volatility 15.04% ​ 17.72% to 33.54% ​ 16.14% Discount rate 0.41% ​ 0.06% to 0.12% ​ 1.61% Annual dividend rate 0.68% ​ 0.80% ​ 0.82%

Prepaid Expenses and Other Cu_2

Prepaid Expenses and Other Current Assets (Tables)	12 Months Ended
	Dec. 31, 2021
Prepaid Expenses and Other Current Assets [Abstract]
Prepaid expenses and other current assets	Prepaid expenses and other current assets consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2021 2020 Income taxes receivable $ 61,305 $ 50,062 Inventory ​ ​ 44,257 ​ ​ 36,729 Prepaid insurance ​ ​ 22,471 ​ ​ 17,552 Prepaid licenses and permits ​ ​ 10,683 ​ ​ 9,847 Other ​ ​ 37,006 ​ ​ 46,524 ​ $ 175,722 $ 160,714

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	12 Months Ended
	Dec. 31, 2021
Property and Equipment, Net [Abstract]
Property and Equipment, Net	Property and equipment, net consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2021 2020 Landfill site costs ​ $ 4,447,530 ​ $ 4,205,968 Rolling stock ​ 2,483,294 ​ 2,227,951 Land, buildings and improvements ​ 1,339,542 ​ 1,147,358 Containers ​ 983,602 ​ 845,386 Machinery and equipment ​ 940,723 ​ 820,533 Construction in progress ​ 82,187 ​ 41,668 ​ ​ 10,276,878 ​ 9,288,864 Less accumulated depreciation and depletion ​ (4,554,929) ​ (4,004,358) ​ ​ $ 5,721,949 ​ $ 5,284,506

Intangible Assets, Net (Tables)

Intangible Assets, Net (Tables)	12 Months Ended
	Dec. 31, 2021
Intangible Assets, Net [Abstract]
Intangible Assets Exclusive of Goodwill	Intangible assets, exclusive of goodwill, consisted of the following at December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ ​ Accumulated Net ​ ​ Carrying ​ Accumulated ​ Impairment ​ Carrying ​ ​ Amount ​ Amortization ​ Loss ​ Amount Finite-lived intangible assets: ​ ​ ​ ​ Long-term franchise agreements and contracts ​ $ 724,128 ​ $ (278,827) ​ $ — ​ $ 445,301 Customer lists ​ 711,047 ​ (450,109) ​ — ​ 260,938 Permits and other ​ 538,481 ​ (94,807) ​ — ​ 443,674 ​ ​ 1,973,656 ​ (823,743) ​ — ​ 1,149,913 Indefinite-lived intangible assets: ​ ​ ​ ​ Solid waste collection and transportation permits ​ 181,613 ​ — ​ — ​ 181,613 E&P facility permits ​ 59,855 ​ — ​ (40,784) ​ 19,071 ​ ​ 241,468 ​ — ​ (40,784) ​ 200,684 Intangible assets, exclusive of goodwill ​ $ 2,215,124 ​ $ (823,743) ​ $ (40,784) ​ $ 1,350,597 Intangible assets, exclusive of goodwill, consisted of the following at December 31, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ ​ Accumulated Net ​ ​ Carrying ​ Accumulated ​ Impairment ​ Carrying ​ ​ Amount ​ Amortization ​ Loss ​ Amount Finite-lived intangible assets: ​ ​ ​ ​ Long-term franchise agreements and contracts ​ $ 600,674 ​ $ (234,972) ​ $ — ​ $ 365,702 Customer lists ​ 636,035 ​ (382,020) ​ — ​ 254,015 Permits and other ​ 378,952 ​ (79,277) ​ — ​ 299,675 ​ ​ 1,615,661 ​ (696,269) ​ — ​ 919,392 Indefinite-lived intangible assets: ​ ​ ​ ​ ​ ​ Solid waste collection and transportation permits ​ 172,056 ​ — ​ — ​ 172,056 Material recycling facility permits ​ 42,283 ​ — ​ — ​ 42,283 E&P facility permits ​ 59,855 ​ — ​ (38,507) ​ 21,348 ​ ​ 274,194 ​ — ​ (38,507) ​ 235,687 Intangible assets, exclusive of goodwill ​ $ 1,889,855 ​ $ (696,269) ​ $ (38,507) ​ $ 1,155,079
Estimated Future Amortization Expense of Amortizable Intangible Assets	Estimated future amortization expense for the next five years relating to finite-lived intangible assets is as follows: ​ ​ ​ ​ ​ For the year ending December 31, 2022 $ 137,771 For the year ending December 31, 2023 ​ $ 119,458 For the year ending December 31, 2024 ​ $ 103,820 For the year ending December 31, 2025 ​ $ 89,002 For the year ending December 31, 2026 ​ $ 75,122

Acquisitions (Tables)

Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2021
Acquisitions [Abstract]
Summary of Consideration Transferred to Acquire Businesses and Amounts of Identifiable Assets Acquired, Liabilities Assumed and Noncontrolling Interests	The following table summarizes the consideration transferred to acquire these businesses and the amounts of identifiable assets acquired and liabilities assumed at the acquisition dates for the acquisitions consummated in the years ended December 31, 2021, 2020 and 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2021 2020 2019 ​ ​ Acquisitions ​ Acquisitions ​ Acquisitions Fair value of consideration transferred: ​ ​ ​ Cash ​ $ 960,449 ​ $ 388,789 ​ $ 736,610 Debt assumed ​ 108,345 ​ 91,349 ​ 95,809 Change in open working capital settlements at year end ​ ​ — ​ ​ 1,505 ​ ​ 5,272 ​ ​ 1,068,794 ​ 481,643 ​ 837,691 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired: ​ ​ ​ Accounts receivable ​ 33,236 ​ 13,759 ​ 25,220 Prepaid expenses and other current assets ​ 4,866 ​ 4,509 ​ 4,970 Operating lease right-of-use assets ​ ​ 5,972 ​ ​ 5,247 ​ ​ 3,616 Property and equipment ​ 394,687 ​ 173,394 ​ 294,037 Long-term franchise agreements and contracts ​ 134,827 ​ 59,149 ​ 78,312 Indefinite-lived intangibles ​ 9,557 ​ 13,465 ​ — Customer lists ​ 75,612 ​ 48,512 ​ 52,422 Permits and other intangibles ​ ​ 116,967 ​ ​ 10,507 ​ ​ 48,141 Other assets ​ 77 ​ 389 ​ 7 Accounts payable and accrued liabilities ​ (37,827) ​ (14,174) ​ (19,209) Current portion of operating lease liabilities ​ ​ (1,370) ​ ​ (509) ​ ​ (658) Deferred revenue ​ (8,389) ​ (1,821) ​ (17,245) Contingent consideration ​ (31,616) ​ (4,688) ​ (14,038) Long-term portion of operating lease liabilities ​ ​ (4,602) ​ ​ (4,738) ​ ​ (2,958) Other long-term liabilities ​ (13,976) ​ (2,136) ​ (8,707) Deferred income taxes ​ (63,822) ​ (4,525) ​ (13,287) Total identifiable net assets ​ 614,199 ​ 296,340 ​ 430,623 Goodwill ​ $ 454,595 ​ $ 185,303 ​ $ 407,068

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2021
Lessee Disclosure [Abstract]
Summary of lease cost	Lease cost for operating and finance leases for the years ended December 31, 2021, 2020 and 2019 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2021 ​ 2020 ​ 2019 Operating lease cost ​ $ 40,381 ​ $ 39,411 ​ $ 38,710 Finance lease cost: ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortization of leased assets ​ ​ 3,424 ​ ​ — ​ ​ — Interest on leased liabilities ​ ​ 152 ​ ​ — ​ ​ — Total lease cost ​ $ 43,957 ​ $ 39,411 ​ $ 38,710 ​ Supplemental cash flow information and non-cash activity related to the Company’s leases are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2021 ​ ​ 2020 ​ ​ 2019 Cash paid for amounts included in the measurement of lease liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating cash flows from operating leases ​ $ 40,249 ​ $ 39,212 ​ $ 38,226 Operating cash flows from finance leases ​ $ 152 ​ $ — ​ $ — Financing cash flows from finance leases ​ $ 3,133 ​ $ — ​ $ — Non-cash activity: ​ ​ ​ ​ ​ ​ ​ ​ ​ Right-of-use assets obtained in exchange for lease liabilities - operating leases ​ $ 17,933 ​ $ 15,117 ​ $ 17,774 Right-of-use assets obtained in exchange for lease liabilities - finance leases ​ $ 10,012 ​ $ 3,754 ​ $ — ​ Weighted-average remaining lease term and discount rate for the Company’s leases are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 ​ 2020 ​ 2019 Weighted average remaining lease term - operating leases ​ 8.0 years 8.6 years 8.7 years Weighted average remaining lease term - finance leases ​ 4.9 years ​ 5.4 years ​ Not applicable ​ Weighted average discount rate - operating leases ​ 3.37 % 3.86 % 3.99 % Weighted average discount rate - finance leases ​ 1.89 % ​ 1.89 % ​ Not applicable ​
Summary of future minimum lease payments, operating leases	As of December 31, 2021, future minimum lease payments, reconciled to the respective lease liabilities, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating Leases ​ ​ Finance Leases 2022 $ 38,956 ​ $ 2,162 2023 ​ 34,060 ​ 2,162 2024 ​ 26,066 ​ 2,162 2025 ​ 19,310 ​ 2,162 2026 ​ 14,455 ​ 2,161 Thereafter ​ 62,747 ​ 234 Minimum lease payments ​ 195,594 ​ 11,043 Less: imputed interest ​ (27,949) ​ (524) Present value of minimum lease payments ​ ​ 167,645 ​ ​ 10,519 Less: current portion of lease liabilities ​ ​ (38,017) ​ ​ (2,061) Long-term portion of lease liabilities ​ $ 129,628 ​ $ 8,458
Summary of future minimum lease payments, finance leases	As of December 31, 2021, future minimum lease payments, reconciled to the respective lease liabilities, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating Leases ​ ​ Finance Leases 2022 $ 38,956 ​ $ 2,162 2023 ​ 34,060 ​ 2,162 2024 ​ 26,066 ​ 2,162 2025 ​ 19,310 ​ 2,162 2026 ​ 14,455 ​ 2,161 Thereafter ​ 62,747 ​ 234 Minimum lease payments ​ 195,594 ​ 11,043 Less: imputed interest ​ (27,949) ​ (524) Present value of minimum lease payments ​ ​ 167,645 ​ ​ 10,519 Less: current portion of lease liabilities ​ ​ (38,017) ​ ​ (2,061) Long-term portion of lease liabilities ​ $ 129,628 ​ $ 8,458

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	12 Months Ended
	Dec. 31, 2021
Accrued Liabilities [Abstract]
Accrued Liabilities	Accrued liabilities consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2021 2020 Insurance claims and premiums ​ $ 149,864 ​ $ 147,188 Payroll and payroll-related ​ 141,877 ​ 141,371 Interest payable ​ 28,729 ​ 29,580 Final capping, closure and post-closure liability ​ ​ 19,925 ​ ​ 19,925 Unrealized cash flow hedge losses ​ 18,675 ​ 20,023 Property taxes ​ ​ 8,833 ​ ​ 6,381 Cell processing reserve ​ 3,364 ​ 3,344 Transaction-related expenses ​ ​ 3,130 ​ ​ 3,304 Share-based compensation plan liability ​ 2,423 ​ 868 Environmental remediation reserve ​ 2,300 ​ 2,300 Other ​ 63,476 ​ 30,639 ​ ​ $ 442,596 ​ $ 404,923

Long-Term Debt (Tables)

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2021
Long-Term Debt [Abstract]
Long-Term Debt	The following table presents the Company’s long-term debt as of December 31, 2021 and 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2021 2020 Revolver under Credit Agreement, bearing interest ranging from 1.10% to 3.25% (a) ​ $ 803,944 ​ $ 203,927 Term loan under Credit Agreement, bearing interest at 1.10% (a) ​ 650,000 ​ ​ 650,000 4.64% Senior Notes due 2021 ​ — ​ ​ 100,000 2.39% Senior Notes due 2021 ​ — ​ ​ 150,000 3.09% Senior Notes due 2022 ​ — ​ ​ 125,000 2.75% Senior Notes due 2023 ​ — ​ ​ 200,000 3.24% Senior Notes due 2024 ​ — ​ ​ 150,000 3.41% Senior Notes due 2025 ​ — ​ ​ 375,000 3.03% Senior Notes due 2026 ​ — ​ ​ 400,000 3.49% Senior Notes due 2027 ​ — ​ ​ 250,000 4.25% Senior Notes due 2028 ​ ​ 500,000 ​ ​ 500,000 3.50% Senior Notes due 2029 ​ ​ 500,000 ​ ​ 500,000 2.60% Senior Notes due 2030 ​ ​ 600,000 ​ ​ 600,000 2.20% Senior Notes due 2032 ​ ​ 650,000 ​ ​ — 3.05% Senior Notes due 2050 ​ ​ 500,000 ​ ​ 500,000 2.95% Senior Notes due 2052 ​ ​ 850,000 ​ ​ — Notes payable to sellers and other third parties, bearing interest ranging from 2.42% to 10.35%, principal and interest payments due periodically with due dates ranging from 2028 to 2036 (a) ​ 37,508 ​ ​ 43,131 Finance leases, bearing interest at 1.89% with a lease expiration date of 2027 (a) ​ ​ 10,519 ​ ​ 3,754 ​ ​ 5,101,971 ​ 4,750,812 Less – current portion ​ (6,020) ​ ​ (8,268) Less – unamortized debt discount and issuance costs ​ (55,451) ​ ​ (33,866) ​ ​ $ 5,040,500 ​ $ 4,708,678 (a) Interest rates represent the interest rates incurred at December 31, 2021.
Details of the Company's Credit Agreement	Details of the Credit Agreement are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2021 2020 Revolver under Credit Agreement ​ ​ ​ Available $ 933,775 ​ $ 1,238,937 ​ Letters of credit outstanding $ 112,281 ​ $ 119,636 ​ Total amount drawn, as follows: $ 803,944 ​ $ 203,927 ​ Amount drawn - U.S. LIBOR rate loan $ 631,000 ​ $ 200,000 ​ Interest rate applicable - U.S. LIBOR rate loan ​ 1.10 % ​ 1.35 % Interest rate margin - U.S. LIBOR rate loan ​ 1.00 % ​ 1.20 % Amount drawn - U.S. base rate loan $ 158,000 ​ $ — ​ Interest rate applicable - U.S. base rate loan ​ 3.25 % ​ — % Interest rate margin - U.S. base rate loan ​ 0.00 % ​ — % Amount drawn - U.S. swingline loan $ 11,000 ​ $ — ​ Interest rate applicable - U.S. swingline loan ​ 3.25 % ​ — % Interest rate margin - U.S. swingline loan ​ 0.00 % ​ — % Amount drawn – Canadian bankers’ acceptance $ 3,944 ​ $ 3,927 ​ Interest rate applicable – Canadian bankers’ acceptance 1.45 % 1.66 % Interest rate acceptance fee – Canadian bankers’ acceptance 1.00 % 1.20 % Commitment – rate applicable 0.09 % 0.15 % Term loan under Credit Agreement ​ ​ ​ ​ Amount drawn – U.S. based LIBOR loan $ 650,000 ​ $ 650,000 ​ Interest rate applicable – U.S. based LIBOR loan 1.10 % 1.35 % Interest rate margin – U.S. based LIBOR loan 1.00 % 1.20 %
Aggregate Contractual Future Principal Payments by Calendar Year on Long-Term Debt	As of December 31, 2021, aggregate contractual future principal payments by calendar year on long-term debt are due as follows: ​ ​ ​ ​ ​ 2022 $ 6,020 2023 ​ 6,090 2024 ​ 6,239 2025 ​ 6,391 2026 ​ 1,460,243 Thereafter ​ 3,616,988 ​ ​ $ 5,101,971

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2021
Fair Value of Financial Instruments [Abstract]
Assets and Liabilities Measured At Fair Value on Recurring Basis	The Company’s assets and liabilities measured at fair value on a recurring basis at December 31, 2021 and 2020, were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurement at December 31, 2021 Using ​ ​ ​ Quoted Prices in Significant ​ ​ ​ ​ ​ ​ ​ Active Markets ​ Other ​ Significant ​ ​ ​ ​ ​ for Identical ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Assets ​ Inputs ​ Inputs ​ ​ Total ​ (Level 1) ​ (Level 2) ​ (Level 3) Interest rate swap derivative instruments – net liability position ​ $ (51,081) ​ $ — ​ $ (51,081) ​ $ — Restricted cash ​ $ 72,174 ​ $ 72,174 ​ $ — ​ $ — Restricted investments ​ $ 58,797 ​ $ — ​ $ 58,797 ​ $ — Contingent consideration ​ $ (94,308) ​ $ — ​ $ — ​ $ (94,308) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurement at December 31, 2020 Using ​ ​ ​ Quoted Prices in Significant ​ ​ ​ ​ ​ ​ ​ Active Markets ​ Other ​ Significant ​ ​ ​ ​ ​ for Identical ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Assets ​ Inputs ​ Inputs ​ ​ Total ​ (Level 1) ​ (Level 2) ​ (Level 3) Interest rate swap derivative instruments – net liability position ​ $ (94,689) ​ $ — ​ $ (94,689) ​ $ — Restricted cash ​ $ 97,095 ​ $ 97,095 ​ $ — ​ $ — Restricted investments ​ $ 58,181 ​ $ — ​ $ 58,181 ​ $ — Contingent consideration ​ $ (71,736) ​ $ — ​ $ — ​ $ (71,736)
Changes in the Fair Value for Level 3 Liabilities Related to Contingent Consideration	The following table summarizes the changes in the fair value for Level 3 liabilities related to contingent consideration for the years ended December 31, 2021 and 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 2020 Beginning balance ​ $ 71,736 ​ $ 69,484 Contingent consideration recorded at acquisition date ​ 31,616 ​ 4,688 Payment of contingent consideration recorded at acquisition date ​ (12,934) ​ (12,566) Payment of contingent consideration recorded in earnings ​ (520) ​ (10,371) Adjustments to contingent consideration ​ ​ 2,954 ​ ​ 18,418 Interest accretion expense ​ 1,470 ​ 2,006 Foreign currency translation adjustment ​ (14) ​ 77 Ending balance ​ $ 94,308 ​ $ 71,736

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2021
Commitments and Contingencies [Abstract]
Future Minimum Purchase Commitments	As of December 31, 2021, future minimum purchase commitments, by calendar year, are as follows: ​ ​ ​ ​ ​ 2022 $ 98,655 2023 ​ 51,289 2024 ​ ​ 1,789 ​ ​ $ 151,733

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common Stock Shares Reserved for Issuance	​ ​ ​ ​ For outstanding RSUs, PSUs and warrants 1,933,004 For future grants under the 2016 Incentive Award Plan 4,066,471 For future grants under the Employee Share Purchase Plan ​ 989,187 ​ 6,988,662
Restricted Stock Units Activity	A summary of the Company’s RSU activity is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 2020 2019 Weighted average grant-date fair value of restricted share units granted ​ $ 100.27 ​ $ 101.79 ​ $ 81.24 Total fair value of restricted share units vested ​ $ 26,711 ​ $ 23,742 ​ $ 21,136
Summary of Warrant Activity	A summary of warrant activity during the year ended December 31, 2021, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ Warrants ​ Exercise Price Outstanding at December 31, 2020 489,748 ​ $ 86.41 Granted 218,166 ​ $ 110.91 Forfeited (82,779) ​ $ 81.35 Exercised (46,730) ​ $ 72.88 Outstanding at December 31, 2021 578,405 ​ $ 104.82
Summarized Information about Warrants Outstanding	The following table summarizes information about warrants outstanding as of December 31, 2021 and 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value of ​ ​ ​ ​ ​ ​ Warrants ​ ​ ​ Warrants ​ Outstanding at December 31, Grant Date ​ Issued ​ Exercise Price ​ Issued ​ 2021 ​ 2020 Throughout 2016 15,666 ​ $42.22 to $51.55 ​ $ 189 — 7,158 Throughout 2017 35,382 ​ $53.65 to $69.96 ​ $ 595 1,521 33,551 Throughout 2018 163,995 ​ $70.91 to $80.90 ​ $ 2,591 112,756 133,141 Throughout 2019 ​ 151,008 ​ $74.25 to $95.61 ​ $ 2,634 ​ 101,977 ​ 151,008 Throughout 2020 ​ 164,890 ​ $72.65 to $104.89 ​ $ 3,140 ​ 146,386 ​ 164,890 Throughout 2021 ​ 218,166 ​ $99.33 to $135.97 ​ $ 5,584 ​ 215,765 ​ — ​ ​ ​ ​ ​ ​ ​ 578,405 489,748
Restricted Stock Units (RSUs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Summary of Activity Related to Restricted Stock Units	A summary of activity related to RSUs during the year ended December 31, 2021, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ Grant Date Fair ​ Unvested Shares ​ Value Per Share Outstanding at December 31, 2020 772,625 ​ $ 84.61 Granted 498,078 ​ $ 100.27 Forfeited (65,528) ​ $ 94.63 Vested and issued (343,480) ​ $ 77.76 Outstanding at December 31, 2021 861,695 ​ $ 95.63
Performance Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance-Based Restricted Share Units Activity	A summary of the Company’s PSU activity is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 2020 2019 Weighted average grant-date fair value of PSUs granted ​ $ 96.99 ​ $ 87.19 ​ $ 80.85 Total fair value of PSUs vested ​ $ 10,954 ​ $ 15,628 ​ $ 7,683
Summary of Performance-Based Restricted Stock Units Activity and Related Information	A summary of activity related to PSUs during the year ended December 31, 2021, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ Grant Date Fair ​ Unvested Shares ​ Value Per Share Outstanding at December 31, 2020 434,558 ​ $ 82.60 Granted 116,784 ​ $ 96.99 Forfeited (5,048) ​ $ 68.58 Vested and issued (154,251) ​ $ 71.01 Outstanding at December 31, 2021 392,043 ​ $ 91.63
Deferred Share Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted Stock Units Activity	A summary of the Company’s deferred share units (“DSUs”) activity is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 ​ 2020 2019 Weighted average grant-date fair value of DSUs granted ​ $ 99.80 ​ $ 103.81 ​ $ 83.80 Total fair value of DSUs awarded ​ $ 285 ​ $ 272 ​ $ 319
Summary of Activity Related to Restricted Stock Units	A summary of activity related to DSUs during the year ended December 31, 2021, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ Grant Date Fair ​ Vested Shares ​ Value Per Share Outstanding at December 31, 2020 21,586 ​ $ 59.32 Granted 2,856 ​ $ 99.80 Outstanding at December 31, 2021 24,442 ​ $ 64.05
Progressive Waste Solutions Ltd. [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Summary of Stock Option Activity and Related Information	​ ​ ​ ​ Outstanding at December 31, 2020 51,200 Cash settled (5,331) Outstanding at December 31, 2021 45,869
Progressive Waste Solutions Ltd. [Member] | Restricted Stock Units (RSUs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Summary of Activity Related to Restricted Stock Units	​ ​ ​ ​ Outstanding at December 31, 2020 66,554 Cash settled (3,522) Outstanding at December 31, 2021 63,032

Other Comprehensive Income (L_2

Other Comprehensive Income (Loss) (Tables)	12 Months Ended
	Dec. 31, 2021
Other Comprehensive Income (Loss) [Abstract]
Components of Other Comprehensive Income (Loss)	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2021 ​ Gross Tax Effect Net of Tax Interest rate swap amounts reclassified into interest expense ​ $ 20,321 ​ $ (5,385) ​ $ 14,936 Changes in fair value of interest rate swaps ​ 23,287 ​ (6,171) ​ 17,116 Foreign currency translation adjustment ​ 8,183 ​ — ​ 8,183 ​ ​ $ 51,791 ​ $ (11,556) ​ $ 40,235 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2020 ​ Gross Tax Effect Net of Tax Interest rate swap amounts reclassified into interest expense ​ $ 9,778 ​ $ (2,591) ​ $ 7,187 Changes in fair value of interest rate swaps ​ (64,664) ​ 17,136 ​ (47,528) Foreign currency translation adjustment ​ 50,653 ​ — ​ 50,653 ​ ​ $ (4,233) ​ $ 14,545 ​ $ 10,312 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2019 ​ Gross Tax Effect Net of Tax Interest rate swap amounts reclassified into interest expense ​ $ (8,027) ​ $ 2,127 ​ $ (5,900) Changes in fair value of interest rate swaps ​ (43,873) ​ 11,626 ​ (32,247) Foreign currency translation adjustment ​ ​ 101,970 ​ ​ — ​ ​ 101,970 ​ ​ $ 50,070 ​ $ 13,753 ​ $ 63,823
Amounts Included in Accumulated Other Comprehensive Loss	A roll forward of the amounts included in AOCIL, net of taxes, is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Foreign Accumulated ​ ​ ​ ​ ​ Currency ​ Other ​ ​ Interest ​ Translation ​ Comprehensive ​ ​ Rate Swaps ​ Adjustment ​ Income (Loss) Balance at December 31, 2019 ​ $ (29,255) ​ $ 18,292 ​ $ (10,963) Amounts reclassified into earnings ​ 7,187 ​ — ​ 7,187 Changes in fair value ​ (47,528) ​ — ​ (47,528) Foreign currency translation adjustment ​ — ​ 50,653 ​ 50,653 Balance at December 31, 2020 ​ ​ (69,596) ​ ​ 68,945 ​ ​ (651) Amounts reclassified into earnings ​ ​ 14,936 ​ ​ — ​ ​ 14,936 Changes in fair value ​ ​ 17,116 ​ ​ — ​ ​ 17,116 Foreign currency translation adjustment ​ ​ — ​ ​ 8,183 ​ ​ 8,183 Balance at December 31, 2021 ​ $ (37,544) ​ $ 77,128 ​ $ 39,584

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2021
Income Taxes [Abstract]
Income (Loss) Before Provision (Benefit) for Income Taxes	Income before provision for income taxes consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 2020 2019 U.S. ​ $ 574,737 ​ $ 22,349 ​ $ 477,203 Non – U.S. ​ 196,005 ​ 231,565 ​ 228,688 Income before income taxes ​ $ 770,742 ​ $ 253,914 ​ $ 705,891
Provision (Benefit) for Income Taxes	The provision for income taxes consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 2020 2019 Current: ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. Federal ​ $ 71,180 ​ $ 65,143 ​ $ 45,475 State ​ 34,439 ​ 28,325 ​ 27,528 Non – U.S. ​ 32,071 ​ 6,941 ​ 11,570 ​ ​ 137,690 ​ 100,409 ​ 84,573 Deferred: ​ ​ ​ U.S. Federal ​ 51,534 ​ (36,659) ​ 58,291 State ​ 5,093 ​ (8,762) ​ 6,331 Non – U.S. ​ (42,064) ​ (5,066) ​ (9,985) ​ ​ 14,563 ​ (50,487) ​ 54,637 Provision for income taxes ​ $ 152,253 ​ $ 49,922 ​ $ 139,210
Significant Components of Deferred Income Tax Assets and Liabilities	The significant components of deferred income tax assets and liabilities, reduced by valuation allowances as applicable, are presented below. ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2021 2020 Deferred income tax assets: ​ ​ Accrued expenses ​ $ 31,840 ​ $ 26,600 Compensation ​ 22,545 ​ 18,150 Contingent liabilities ​ 21,268 ​ 17,652 Tax credits and loss carryforwards ​ 24,415 ​ 24,044 Interest rate and fuel hedges ​ 13,536 ​ 25,093 Finance costs ​ 24,264 ​ — Other ​ ​ — ​ ​ 872 Gross deferred income tax assets ​ 137,868 ​ 112,411 Less: Valuation allowance ​ — ​ — Total deferred income tax assets ​ 137,868 ​ 112,411 ​ ​ ​ ​ ​ ​ ​ Deferred income tax liabilities: ​ ​ ​ ​ ​ ​ Goodwill and other intangibles ​ (397,855) ​ (332,097) Property and equipment ​ (484,519) ​ (440,019) Landfill closure/post-closure ​ (18,597) ​ (13,846) Prepaid expenses ​ (11,534) ​ (14,990) Investment in subsidiaries ​ (69,286) ​ (69,391) Finance costs ​ ​ — ​ ​ (2,112) Other ​ ​ (6,998) ​ ​ — Total deferred income tax liabilities ​ (988,789) ​ (872,455) Net deferred income tax liability ​ $ (850,921) ​ $ (760,044)
Differences between Income Tax Provision in Statements of Net Income and Income Tax Provision Computed at Federal Statutory Rate	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 2020 2019 U.S. federal statutory rate ​ 21.0 % 21.0 % 21.0 % State taxes, net of federal benefit 4.7 4.5 4.4 ​ Deferred income tax liability adjustments 0.3 1.6 0.6 ​ Effect of international operations (6.3) (7.0) (6.3) ​ Other 0.1 (0.4) — ​ ​ 19.8 % 19.7 % 19.7 %

Segment Reporting (Tables)

Segment Reporting (Tables)	12 Months Ended
	Dec. 31, 2021
Segment Reporting [Abstract]
Summary of Financial Information Concerning Company's Reportable Segments	Summarized financial information concerning the Company’s reportable segments for the years ended December 31, 2021, 2020 and 2019, is shown in the following tables: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ Intercompany ​ Reported ​ Segment ​ Depreciation and ​ Capital ​ ​ ​ December 31, 2021 Revenue Revenue (b) Revenue EBITDA (c) Amortization Expenditures Total Assets (e) Eastern ​ $ 1,807,563 ​ $ (286,275) ​ $ 1,521,288 ​ $ 404,493 ​ $ 239,130 ​ $ 174,350 ​ $ 3,652,311 Southern ​ ​ 1,633,402 ​ ​ (186,656) ​ ​ 1,446,746 ​ ​ 394,982 ​ ​ 188,977 ​ ​ 156,527 ​ ​ 3,513,355 Western ​ 1,434,844 ​ (154,656) ​ 1,280,188 ​ 405,778 ​ 129,988 ​ 152,149 ​ 2,260,222 Central ​ 1,188,501 ​ (142,085) ​ 1,046,416 ​ 359,434 ​ 134,078 ​ 144,458 ​ 2,332,564 Canada ​ 965,705 ​ (108,982) ​ 856,723 ​ 339,859 ​ 111,458 ​ 68,183 ​ 2,513,608 Corporate (a), (d) ​ — ​ — ​ — ​ (19,596) ​ 9,378 ​ 48,648 ​ 427,864 ​ ​ $ 7,030,015 ​ $ (878,654) ​ $ 6,151,361 ​ $ 1,884,950 ​ $ 813,009 ​ $ 744,315 ​ $ 14,699,924 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ Intercompany ​ Reported ​ Segment ​ Depreciation and ​ Capital ​ ​ ​ December 31, 2020 Revenue Revenue (b) Revenue EBITDA (c) Amortization Expenditures Total Assets (e) Eastern ​ $ 1,601,980 ​ $ (266,115) ​ $ 1,335,865 ​ $ 343,446 ​ $ 222,934 ​ $ 181,787 ​ $ 3,134,462 Southern ​ ​ 1,552,687 ​ ​ (183,107) ​ ​ 1,369,580 ​ ​ 369,445 ​ ​ 189,726 ​ ​ 131,831 ​ ​ 3,402,081 Western ​ 1,291,882 ​ (142,120) ​ 1,149,762 ​ 364,790 ​ 115,151 ​ 132,344 ​ 1,861,079 Central ​ 1,008,081 ​ (127,758) ​ 880,323 ​ 313,033 ​ 113,004 ​ 102,966 ​ 2,160,246 Canada ​ 805,757 ​ (95,297) ​ 710,460 ​ 256,119 ​ 103,334 ​ 109,886 ​ 2,544,379 Corporate (a), (d) ​ — ​ — ​ — ​ (15,283) ​ 8,255 ​ 5,747 ​ 890,117 ​ ​ $ 6,260,387 ​ $ (814,397) ​ $ 5,445,990 ​ $ 1,631,550 ​ $ 752,404 ​ $ 664,561 ​ $ 13,992,364 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ Intercompany ​ Reported ​ Segment ​ Depreciation and ​ Capital ​ ​ ​ December 31, 2019 Revenue Revenue (b) Revenue EBITDA (c) Amortization Expenditures Total Assets (e) Eastern ​ $ 1,524,648 ​ $ (255,684) ​ $ 1,268,964 ​ $ 330,578 ​ $ 204,221 ​ $ 154,218 ​ $ 3,099,283 Southern ​ ​ 1,623,614 ​ ​ (174,614) ​ ​ 1,449,000 ​ ​ 441,425 ​ ​ 208,967 ​ ​ 178,127 ​ ​ 3,952,449 Western ​ 1,234,669 ​ (135,820) ​ 1,098,849 ​ 338,563 ​ 102,067 ​ 147,893 ​ 1,718,015 Central ​ 958,139 ​ (119,555) ​ 838,584 ​ 292,111 ​ 106,391 ​ 116,831 ​ 1,885,468 Canada ​ 835,603 ​ (102,321) ​ 733,282 ​ 256,405 ​ 113,944 ​ 61,119 ​ 2,490,291 Corporate (a), (d) ​ — ​ — ​ — ​ (15,438) ​ 8,328 ​ 7,901 ​ 592,189 ​ ​ $ 6,176,673 ​ $ (787,994) ​ $ 5,388,679 ​ $ 1,643,644 ​ $ 743,918 ​ $ 666,089 ​ $ 13,737,695 (a) The majority of Corporate expenses are allocated to the five operating segments. Direct acquisition expenses, expenses associated with common shares held in the deferred compensation plan exchanged for other investment options and share-based compensation expenses associated with Progressive Waste share-based grants outstanding at June 1, 2016 that were continued by the Company are not allocated to the five operating segments and comprise the net EBITDA of the Company’s Corporate segment for the periods presented. (b) Intercompany revenues reflect each segment’s total intercompany sales, including intercompany sales within a segment and between segments. Transactions within and between segments are generally made on a basis intended to reflect the market value of the service. (c) For those items included in the determination of segment EBITDA, the accounting policies of the segments are the same as those described in Note 3. (d) Corporate assets include cash, debt issuance costs, equity investments, operating lease right-of-use assets and corporate facility leasehold improvements and equipment. (e) Goodwill is included within total assets for each of the Company’s five operating segments.
Changes in Goodwill by Reportable Segment	The following table shows changes in goodwill during the years ended December 31, 2020 and 2021, by reportable segment: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Eastern Southern Western Central Canada Total Balance as of December 31, 2019 ​ $ 1,331,180 ​ $ 1,528,225 ​ $ 400,037 ​ $ 729,470 ​ $ 1,521,939 ​ $ 5,510,851 Goodwill acquired ​ 43,397 ​ 3,990 ​ 42,825 ​ 94,883 ​ 208 ​ 185,303 Goodwill divested ​ ​ — ​ ​ — ​ ​ — ​ ​ (149) ​ ​ — ​ ​ (149) Impact of changes in foreign currency ​ — ​ — ​ — ​ — ​ 30,645 ​ 30,645 Balance as of December 31, 2020 ​ ​ 1,374,577 ​ ​ 1,532,215 ​ ​ 442,862 ​ ​ 824,204 ​ ​ 1,552,792 ​ ​ 5,726,650 Goodwill acquired ​ 233,146 ​ 56,576 ​ ​ 96,870 ​ 68,005 ​ ​ — ​ 454,597 Goodwill acquisition adjustments ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ (2) ​ ​ (2) Goodwill divested ​ — ​ (324) ​ — ​ — ​ — ​ (324) Impact of changes in foreign currency ​ — ​ — ​ — ​ — ​ 6,722 ​ 6,722 Balance as of December 31, 2021 ​ $ 1,607,723 ​ $ 1,588,467 ​ $ 539,732 ​ $ 892,209 ​ $ 1,559,512 ​ $ 6,187,643
Property and Equipment, Net Relating to Operations	Property and equipment, net relating to operations in the United States and Canada are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2021 2020 United States ​ $ 5,075,184 ​ $ 4,589,144 Canada ​ 646,765 ​ 695,362 Total ​ $ 5,721,949 ​ $ 5,284,506
Reconciliation of Primary Measure of Segment Profitability to Income before Income Tax Provision	A reconciliation of the Company’s primary measure of segment profitability (segment EBITDA) to Income before income tax provision in the Consolidated Statements of Net Income is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years ended December 31, ​ 2021 2020 2019 Eastern segment EBITDA ​ $ 404,493 ​ $ 343,446 ​ $ 330,578 Southern segment EBITDA ​ ​ 394,982 ​ ​ 369,445 ​ ​ 441,425 Western segment EBITDA ​ 405,778 ​ 364,790 ​ 338,563 Central segment EBITDA ​ 359,434 ​ 313,033 ​ 292,111 Canada segment EBITDA ​ 339,859 ​ 256,119 ​ 256,405 Subtotal reportable segments ​ 1,904,546 ​ 1,646,833 ​ 1,659,082 Unallocated corporate overhead ​ (19,596) ​ (15,283) ​ (15,438) Depreciation ​ (673,730) ​ (621,102) ​ (618,396) Amortization of intangibles ​ (139,279) ​ (131,302) ​ (125,522) Impairments and other operating items ​ (32,316) ​ (466,718) ​ (61,948) Interest expense ​ (162,796) ​ (162,375) ​ (147,368) Interest income ​ 2,916 ​ 5,253 ​ 9,777 Other income (expense), net ​ 6,285 ​ (1,392) ​ 5,704 Loss on early extinguishment of debt ​ ​ (115,288) ​ ​ — ​ ​ — Income before income tax provision ​ $ 770,742 ​ $ 253,914 ​ $ 705,891

Net Income Per Share Informat_2

Net Income Per Share Information (Tables)	12 Months Ended
	Dec. 31, 2021
Net Income Per Share Information [Abstract]
Basic and Diluted Net Income (Loss) Per Common Share	The following table sets forth the calculation of the numerator and denominator used in the computation of basic and diluted net income per common share attributable to the Company’s shareholders for the years ended December 31, 2021, 2020 and 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2021 2020 2019 Numerator: ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income attributable to Waste Connections for basic and diluted earnings per share ​ $ 618,047 ​ $ 204,677 ​ $ 566,841 Denominator: ​ ​ ​ ​ ​ ​ Basic shares outstanding ​ 261,166,723 ​ 263,189,699 ​ 263,792,693 Dilutive effect of equity-based awards ​ 561,747 ​ 497,840 ​ 733,868 Diluted shares outstanding ​ 261,728,470 ​ 263,687,539 ​ 264,526,561

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2021
Employee Benefit Plans [Abstract]
Multiemployer Pension Plan	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Expiration ​ ​ EIN/Pension Plan ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Date of ​ ​ Number/ ​ Pension Protection Act ​ FIP/RP ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Collective ​ ​ Registration ​ Zone Status (a) ​ Status ​ Company Contributions (d) ​ Bargaining Plan Name Number 2021 2020 (b),(c) 2021 2020 2019 Agreement Western Conference of Teamsters Pension Trust 91-6145047 - 001 Green Green Not applicable ​ $ 4,963 ​ $ 4,841 ​ $ 4,550 12/31/2021 to 6/30/2025 Local 731, I.B. of T., Pension Fund 36-6513567 - 001 Green for the plan year beginning 10/1/2021 Green for the plan year beginning 10/1/2019 Not applicable ​ ​ 4,504 ​ ​ 4,628 ​ ​ 4,570 9/30/2023 Suburban Teamsters of Northern Illinois Pension Fund 36-6155778 - 001 Green Green Not applicable ​ 2,300 ​ 2,080 ​ 1,844 2/29/2024 Teamsters Local 301 Pension Fund 36-6492992 - 001 Green Green Not applicable ​ 841 ​ 673 ​ 624 9/30/2023 Automobile Mechanics’ Local No. 701 Union and Industry Pension Fund 36-6042061 - 001 Green Green Not applicable ​ 439 ​ 457 ​ 492 12/31/2022 Midwest Operating Engineers Pension Plan 36-6140097 - 001 Green for the plan year beginning 4/1/2021 Green for the plan year beginning 4/1/2020 Not applicable ​ 424 ​ 316 ​ 339 10/31/2025 Locals 302 & 612 of the IOUE - Employers Construction Industry Retirement Plan 91-6028571 - 001 Green Green Not applicable ​ 313 ​ 298 ​ 290 11/16/2022 IAM National Pension Fund ​ 51-6031295 - 002 ​ Critical ​ Critical ​ Implemented ​ ​ 299 ​ ​ 310 ​ ​ 256 ​ 12/31/2022 International Union of Operating Engineers Pension Trust 85512-1 Green as of 4/30/2020 Green as of 4/30/2018 Not applicable ​ 295 ​ 279 ​ 238 3/31/2021 to 3/31/2024 Multi-Sector Pension Plan 1085653 Green as of 1/1/2021 Green as of 1/1/2020 Not applicable ​ 265 ​ 196 ​ 202 12/31/2023 Local 813 Pension Trust Fund 13-1975659 - 001 Critical for the plan year beginning 1/1/2021 Critical Implemented ​ 258 ​ 183 ​ 281 11/30/2022 Recycling and General Industrial Union Local 108 Pension Fund ​ 13-6366378 ​ Green ​ Green ​ Not applicable ​ ​ 217 ​ ​ 269 ​ ​ 337 ​ 2/28/2022 Nurses and Local 813 IBT Retirement Plan ​ 13-3628926 - 001 ​ Green ​ Green ​ Not applicable ​ ​ 58 ​ ​ 52 ​ ​ 87 ​ 11/30/2022 Contributions to other multiemployer plans ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 75 ​ ​ 10 ​ ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 15,251 ​ $ 14,592 ​ $ 14,110 ​ ​ ​ (a) Unless otherwise noted in the table above, the most recent Pension Protection Act zone status available in 2021 and 2020 is for the plans’ years ended December 31, 2020 and 2019, respectively. (b) The “FIP/RP Status” column indicates plans for which a Funding Improvement Plan (“FIP”) or a Rehabilitation Plan (“RP”) has been implemented. (c) A multiemployer defined benefit pension plan that has been certified as endangered, seriously endangered or critical may begin to levy a statutory surcharge on contribution rates. Once authorized, the surcharge is at the rate of 5% for the first 12 months and 10% for any periods thereafter, until certain conditions are met. The Company was not required to pay a surcharge to these plans during the years ended December 31, 2021 and 2020. (d) Of the Multiemployer Pension Plans considered to be individually significant, the Company was listed in the Form 5500 as providing more than 5% of the total contributions for the following: 1) Local No. 731, I.B. of T., Pension Fund for plan years ending September 30, 2020, 2019 and 2018; 2) Teamsters Local 301 Pension Fund for plan years ending December 31, 2020, 2019 and 2018; 3) Suburban Teamsters of Northern Illinois Pension Plan for the plan year ending December 31, 2020; and 4) Recycling and General Industrial Union Local 108 Pension Fund for the plan years ending December 31, 2020, 2019 and 2018.

New Accounting Standards and _3

New Accounting Standards and Reclassifications (New Accounting Standards) (Details) - Credit Agreement [Member] - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Term Loan Facility [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Long term debt	$ 650,000	$ 650,000
Revolving Credit Facility [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Long term debt	803,944	203,927
Revolving Credit Facility [Member] | Base Rate [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Long term debt	158,000
Revolving Credit Facility [Member] | LIBOR [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Long term debt	631,000	200,000
Revolving Credit Facility [Member] | LIBOR [Member] | Term Loan Facility [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Long term debt	1,281,000
Revolving Credit Facility [Member] | Canadian Bankers Acceptance Loan [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Long term debt	3,944	$ 3,927
Maximum [Member] | Revolving Credit Facility [Member] | Term Loan Facility [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Increase in annual interest expense estimated from reference rate reform change	$ 1,000

Summary of Significant Accoun_4

Summary of Significant Accounting Policies (Narrative) (Details) $ in Thousands	Sep. 28, 2020USD ($)item	Jul. 01, 2020segment	Dec. 31, 2021USD ($)agreementsite	Jun. 30, 2020USD ($)	Dec. 31, 2021USD ($)segmentagreementsite	Dec. 31, 2020USD ($)segmentitem	Dec. 31, 2019USD ($)segment	Dec. 31, 2020USD ($)segment	Dec. 31, 2018USD ($)
Organization And Summary Of Significant Accounting Policies [Line Items]
Deferred sales incentives			$ 18,954		$ 18,954	$ 19,669		$ 19,669
Sales incentives amortization expense					$ 23,671	17,138	$ 19,673
Life of Company's owned landfills and landfills operated under life of site operating agreements min range					1 year
Life of Company's owned landfills and landfills operated under life of site operating agreements max range					282 years
Threshold period used for measurement of projected annual disposal volume from landfills					70 years
Restricted cash			72,174		$ 72,174	97,095		97,095
Restricted investments			59,014		59,014	57,516		57,516
Cell processing reserve, current			$ 3,364		$ 3,364	3,344		3,344
Perpetual revenue growth rate					4.50%
Weighted average cost of capital			6.10%		6.10%
Goodwill			$ 6,187,643		$ 6,187,643	5,726,650	5,510,851	5,726,650
Number of operating segments | segment					5
Number of operating segments aggregated | segment		2
Intangible assets			1,350,597		$ 1,350,597	1,155,079		$ 1,155,079
Adjustments to contingent consideration					2,954	18,418	1,498
Liability adjustments					(1,081)	$ 2,490
Carrying of liability-classified contingent consideration			$ 31,616		$ 31,616		$ 14,038
Number of geographic operating segments | segment					5	5	5	5
Forecasts period used for discounted cash flow analyses					10 years
Number of interest rate swap agreements | agreement			6		6
Percentage of projected annual disposal volume from landfills with remaining lives within threshold period			90.00%		90.00%
Contractual life of warrants					5 years
Share-based compensation expense					$ 58,221	$ 45,751	$ 42,671
Share-based compensation expense, net of taxes					43,495	34,197	31,926
Advertising costs					7,155	4,870	5,410
Accrual for self insured liabilities			$ 147,757		147,757	140,182		$ 140,182
Self-insurance expense					$ 179,250	$ 164,099	$ 155,748
Statutory income tax rate					21.00%	21.00%	21.00%
Cumulative effect adjustment from adoption of new accounting pronouncement			6,993,545		$ 6,993,545	$ 6,863,438	$ 6,938,354	6,863,438	$ 6,460,188
Deferred income taxes			850,921		850,921	760,044		760,044
Operating lease liability			167,645		167,645
Lease right-of-use assets			160,567		$ 160,567	170,923		170,923
Minimum [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Estimated life of relevant customer relationship					1 year
Expected term of related agreements					1 year
Maximum [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Estimated life of relevant customer relationship					5 years
Expected term of related agreements					40 years
Interest Rate Swap [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Number of derivatives terminated | item	4
Payments to terminate derivative	$ 853
Interest Rate Swap Terminated One [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Notional amount	150,000
Interest Rate Swap Terminated Two [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Notional amount	150,000
Interest Rate Swap Terminated Three [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Notional amount	50,000
Interest Rate Swap Terminated Four [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Notional amount	$ 50,000
Interest Rate Swap One [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Notional amount			100,000		$ 100,000
Interest Rate Swap Two [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Notional amount			200,000		200,000
Interest Rate Swap Three [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Notional amount			150,000		150,000
Interest Rate Swap Four [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Notional amount			200,000		200,000
Restricted Stock Units (RSUs) [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Unrecognized compensation cost related to unvested awards			57,822		$ 57,822
Restricted stock unit awards, vesting final year					2026
Weighted average remaining vesting period					1 year 4 months 24 days
Restricted Stock Units (RSUs) [Member] | Progressive Waste Plans [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Share-based compensation liability			9,008		$ 9,008	7,237	$ 7,178	7,237
Performance Shares [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Unrecognized compensation cost related to unvested awards			20,621		$ 20,621
Restricted stock unit awards, vesting final year					2024
Weighted average remaining vesting period					1 year 1 month 6 days
Employee Stock Option [Member] | Progressive Waste Plans [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Contractual life of warrants					1 year		1 year 6 months
Share-based compensation liability			4,088		$ 4,088	$ 3,556	$ 8,559	3,556
Employee Stock Option [Member] | Minimum [Member] | Progressive Waste Plans [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Contractual life of warrants						6 months
Employee Stock Option [Member] | Maximum [Member] | Progressive Waste Plans [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Contractual life of warrants						1 year
Western [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Goodwill			539,732		539,732	$ 442,862	400,037	442,862
Central [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Goodwill			892,209		892,209	824,204	729,470	824,204
Eastern [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Goodwill			1,607,723		1,607,723	1,374,577	1,331,180	1,374,577
Southern [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Goodwill			1,588,467		1,588,467	1,532,215	1,528,225	1,532,215
Canada Segment [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Goodwill			$ 1,559,512		1,559,512	1,552,792	1,521,939	1,552,792
Exploration and Production [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Goodwill						0	0	$ 0
Adjustments to contingent consideration						$ 4,145
Impairment charges							8,000
Exploration and Production [Member] | Certain Basins [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Percentage decline in revenue from prior year period						56.00%
Exploration and Production [Member] | Four Landfill [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Impairment of property and equipment						$ 417,384
Impairment of intangible assets				$ 0
Intangible assets				$ 0
Exploration and Production [Member] | Valuation Technique, Discounted Cash Flow [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Number of landfills impaired | item						4
Impairment of property and equipment						$ 417,384
Exploration and Production [Member] | Valuation Technique, Discounted Cash Flow [Member] | Four Landfill [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Impairment charge if estimated annual cash flows was changed by ten percent						3,000
Exploration and Production and Sothern [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Number of sites impaired | site			2
Impairment of property and equipment					16,379
Indefinite-lived intangible asset write-down			$ 2,277
Geographic Operating Segments [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Impairment loss					$ 0	0	0
Indefinite-lived intangible asset write-down						$ 0	$ 0
Landfill and Transfer Station [Member] | Minimum [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Standard customer service agreement period					1 year
Landfill and Transfer Station [Member] | Maximum [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Standard customer service agreement period					10 years
Solid Waste Collection | Minimum [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Standard customer service agreement period					1 year
Solid Waste Collection | Maximum [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Standard customer service agreement period					3 years
Landfill Site Costs [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Inflation rate for purposes of computing layers for final capping, closure and post-closure obligations					2.25%	2.50%
E&P Waste Treatment, Recovery and Disposal [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Change in revenue						$ 112,114
E&P Waste Treatment, Recovery and Disposal [Member] | Southern [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Number of sites impaired | site					3
Measurement Input, Expected Term [Member] | Exploration and Production [Member] | Valuation Technique, Discounted Cash Flow [Member] | Four Landfill [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Useful life						40 years
Measurement Input, Discount Rate [Member] | Exploration and Production [Member] | Valuation Technique, Discounted Cash Flow [Member] | Four Landfill [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Derivative Asset (Liability) Net, Measurement Input						0.12		0.12
Measurement Input, Discount Rate [Member] | Landfill Site Costs [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Discount rate			3.25%		3.25%	4.75%		4.75%
Employee Share Purchase Plan 2020 [Member] | Minimum [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Exercise price percentage of closing price of common share					85.00%
Employee Share Purchase Plan 2020 [Member] | Maximum [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Exercise price percentage of closing price of common share					95.00%

Summary of Significant Accoun_5

Summary of Significant Accounting Policies (Total Reported Revenues by Service Line) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue from External Customer [Line Items]
Revenues	$ 6,151,361	$ 5,445,990	$ 5,388,679
Operating Segments [Member] | Solid Waste Collection
Revenue from External Customer [Line Items]
Revenues	4,441,426	3,971,678	3,815,153
Operating Segments [Member] | Solid Waste Collection | Commercial [Member]
Revenue from External Customer [Line Items]
Revenues	1,813,426	1,610,313	1,593,217
Operating Segments [Member] | Solid Waste Collection | Residential [Member]
Revenue from External Customer [Line Items]
Revenues	1,673,819	1,528,217	1,380,763
Operating Segments [Member] | Solid Waste Collection | Industrial and Construction Roll Off [Member]
Revenue from External Customer [Line Items]
Revenues	954,181	833,148	841,173
Operating Segments [Member] | Landfill Site Costs [Member]
Revenue from External Customer [Line Items]
Revenues	1,233,499	1,146,732	1,132,935
Operating Segments [Member] | Transfer [Member]
Revenue from External Customer [Line Items]
Revenues	859,113	777,754	771,316
Operating Segments [Member] | Recycling
Revenue from External Customer [Line Items]
Revenues	205,076	86,389	64,245
Operating Segments [Member] | E&P Waste Treatment, Recovery and Disposal [Member]
Revenue from External Customer [Line Items]
Revenues	138,707	159,438	271,887
Operating Segments [Member] | Intermodal and Other
Revenue from External Customer [Line Items]
Revenues	152,194	118,396	121,137
Intercompany Revenues [Member]
Revenue from External Customer [Line Items]
Revenues	$ (878,654)	$ (814,397)	$ (787,994)

Summary of Significant Accoun_6

Summary of Significant Accounting Policies (Allowance for Credit Losses) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Summary of Significant Accounting Policies [Abstract]
Beginning balance	$ 19,380	$ 16,432
Current period provision for expected credit losses	9,719	15,509	$ 11,973
Write-offs charged against the allowance	(15,545)	(18,318)
Recoveries collected	4,918	5,720
Impact of changes in foreign currency	8	37
Ending balance	$ 18,480	$ 19,380	$ 16,432

Summary of Significant Accoun_7

Summary of Significant Accounting Policies (Property Plant and Equipment Estimated Useful Lives) (Detail)	12 Months Ended
	Dec. 31, 2021
Buildings [Member] | Minimum [Member]
Property Plant and Equipment Estimated Useful Lives [Line Items]
Property, Plant and Equipment	10 years
Buildings [Member] | Maximum [Member]
Property Plant and Equipment Estimated Useful Lives [Line Items]
Property, Plant and Equipment	20 years
Leasehold and Land Improvements [Member] | Minimum [Member]
Property Plant and Equipment Estimated Useful Lives [Line Items]
Property, Plant and Equipment	3 years
Leasehold and Land Improvements [Member] | Maximum [Member]
Property Plant and Equipment Estimated Useful Lives [Line Items]
Property, Plant and Equipment	10 years
Machinery and Equipment [Member] | Minimum [Member]
Property Plant and Equipment Estimated Useful Lives [Line Items]
Property, Plant and Equipment	3 years
Machinery and Equipment [Member] | Maximum [Member]
Property Plant and Equipment Estimated Useful Lives [Line Items]
Property, Plant and Equipment	12 years
Rolling Stock [Member] | Minimum [Member]
Property Plant and Equipment Estimated Useful Lives [Line Items]
Property, Plant and Equipment	3 years
Rolling Stock [Member] | Maximum [Member]
Property Plant and Equipment Estimated Useful Lives [Line Items]
Property, Plant and Equipment	10 years
Containers [Member] | Minimum [Member]
Property Plant and Equipment Estimated Useful Lives [Line Items]
Property, Plant and Equipment	3 years
Containers [Member] | Maximum [Member]
Property Plant and Equipment Estimated Useful Lives [Line Items]
Property, Plant and Equipment	12 years

Summary of Significant Accoun_8

Summary of Significant Accounting Policies (Reconciliation of Final Capping, Closure and Post-Closure Liability Balance) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Business [Abstract]
Final capping, closure and post-closure liability at the beginning of the period	$ 301,896	$ 291,474
Liability adjustments	(1,081)	2,490
Accretion expense associated with landfill obligations	14,333	14,874
Closure payments	(21,040)	(6,488)
Assumption of closure liabilities from acquisitions	11,380	2,136
Disposition of closure liabilities from divested operations	(3,566)	(3,413)
Foreign currency translation adjustment	615	823
Final capping, closure and post-closure liability at the end of the period	$ 302,537	$ 301,896

Summary of Significant Accoun_9

Summary of Significant Accounting Policies (Restricted Cash and Investments) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Restricted cash	$ 72,174	$ 97,095
Restricted investments	59,014	57,516
Restricted Settlement of Insurance Claims [Member]
Restricted cash	52,906	78,335
Restricted Landfill Closure and Post-Closure Obligations [Member]
Restricted cash	12,609	12,533
Restricted investments	56,289	54,833
Restricted Other Financial Assurance Requirements [Member]
Restricted cash	6,659	6,227
Restricted investments	$ 2,725	$ 2,683

Summary of Significant Accou_10

Summary of Significant Accounting Policies (Carrying Values and Fair Values of Debt Instruments) (Details) - Senior Notes [Member] - USD ($)	12 Months Ended
	Dec. 31, 2021	Sep. 20, 2021	Aug. 31, 2021	Dec. 31, 2020	Jan. 23, 2020
Senior Notes due 2021 [Member]
Debt Instrument [Line Items]
Carrying value of senior notes	$ 100,000,000			$ 100,000,000
Fair value of senior notes				$ 100,850,000
Interest rate of senior notes				4.64%
Senior note year due	2021
New Senior Notes due 2021 [Member]
Debt Instrument [Line Items]
Carrying value of senior notes			$ 150,000,000	$ 150,000,000
Fair value of senior notes				$ 150,695,000
Interest rate of senior notes				2.39%
Senior note year due	2021
Senior Notes due 2022 [Member]
Debt Instrument [Line Items]
Carrying value of senior notes	$ 125,000,000			$ 125,000,000
Fair value of senior notes				$ 128,482,000
Interest rate of senior notes				3.09%
Senior note year due	2022
Senior Notes due 2023 [Member]
Debt Instrument [Line Items]
Carrying value of senior notes	$ 200,000,000			$ 200,000,000
Fair value of senior notes				$ 206,204,000
Interest rate of senior notes				2.75%
Senior note year due	2023
Senior Notes due 2024 [Member]
Debt Instrument [Line Items]
Carrying value of senior notes			150,000,000	$ 150,000,000
Fair value of senior notes				$ 158,140,000
Interest rate of senior notes				3.24%
Senior note year due	2024
Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Carrying value of senior notes	$ 375,000,000			$ 375,000,000
Fair value of senior notes				$ 403,025,000
Interest rate of senior notes				3.41%
Senior note year due	2025
Senior Notes due 2026 [Member]
Debt Instrument [Line Items]
Carrying value of senior notes			400,000,000	$ 400,000,000
Fair value of senior notes				$ 424,874,000
Interest rate of senior notes				3.03%
Senior note year due	2026
Senior Notes due 2027 [Member]
Debt Instrument [Line Items]
Carrying value of senior notes			$ 250,000,000	$ 250,000,000
Fair value of senior notes				$ 271,198,000
Interest rate of senior notes				3.49%
Senior note year due	2027
Senior Notes due 2028 [Member]
Debt Instrument [Line Items]
Carrying value of senior notes	$ 500,000,000			$ 500,000,000
Fair value of senior notes	$ 561,350,000			$ 597,050,000
Interest rate of senior notes	4.25%			4.25%
Senior note year due	2028
Senior Notes due 2029 [Member]
Debt Instrument [Line Items]
Carrying value of senior notes	$ 500,000,000			$ 500,000,000
Fair value of senior notes	$ 539,500,000			$ 570,450,000
Interest rate of senior notes	3.50%			3.50%
Senior note year due	2029
Senior Notes due 2030 [Member]
Debt Instrument [Line Items]
Carrying value of senior notes	$ 600,000,000			$ 600,000,000
Fair value of senior notes	$ 610,440,000			$ 644,520,000
Interest rate of senior notes	2.60%			2.60%	2.60%
Senior note year due	2030
Senior Notes due 2032 [Member]
Debt Instrument [Line Items]
Carrying value of senior notes	$ 650,000,000
Fair value of senior notes	$ 637,065,000
Interest rate of senior notes	2.20%	2.20%
Senior note year due	2032
Senior Notes due 2050 [Member]
Debt Instrument [Line Items]
Carrying value of senior notes	$ 500,000,000			$ 500,000,000
Fair value of senior notes	$ 496,350,000			$ 540,050,000
Interest rate of senior notes	3.05%			3.05%
Senior note year due	2050
Senior Notes due 2052 [Member]
Debt Instrument [Line Items]
Carrying value of senior notes	$ 850,000,000
Fair value of senior notes	$ 828,580,000
Interest rate of senior notes	2.95%	2.95%
Senior note year due	2052

Summary of Significant Accou_11

Summary of Significant Accounting Policies (Company's Derivative Instruments of Interest Rate Swaps) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021USD ($)
Interest Rate Swap One [Member]
Derivative [Line Items]
Date entered	2017-08
Notional amount	$ 100,000
Fixed interest rate paid	1.90%
Description of variable rate basis	1-month LIBOR
Effective date	2019-07
Expiration date	2022-07
Interest Rate Swap Two [Member]
Derivative [Line Items]
Date entered	2017-08
Notional amount	$ 200,000
Fixed interest rate paid	2.20%
Description of variable rate basis	1-month LIBOR
Effective date	2020-10
Expiration date	2025-10
Interest Rate Swap Three [Member]
Derivative [Line Items]
Date entered	2017-08
Notional amount	$ 150,000
Fixed interest rate paid	1.95%
Description of variable rate basis	1-month LIBOR
Effective date	2020-02
Expiration date	2023-02
Interest Rate Swap Four [Member]
Derivative [Line Items]
Date entered	2018-06
Notional amount	$ 200,000
Fixed interest rate paid	2.925%
Description of variable rate basis	1-month LIBOR
Effective date	2020-10
Expiration date	2025-10
Interest Rate Swap Five [Member]
Derivative [Line Items]
Date entered	2018-06
Notional amount	$ 200,000
Fixed interest rate paid	2.925%
Description of variable rate basis	1-month LIBOR
Effective date	2020-10
Expiration date	2025-10
Interest Rate Swap Six [Member]
Derivative [Line Items]
Date entered	2018-12
Notional amount	$ 200,000
Fixed interest rate paid	2.85%
Description of variable rate basis	1-month LIBOR
Effective date	2022-07
Expiration date	2027-07

Summary of Significant Accou_12

Summary of Significant Accounting Policies (Fair Values of Derivative Instruments Designated as Cash Flow Hedges) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Derivatives designated as cash flow hedges, liability derivatives	$ (51,081)	$ (94,689)
Other Long-term Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivatives designated as cash flow hedges, liability derivatives		(74,666)
Interest Rate Swap [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivatives designated as cash flow hedges, liability derivatives	(18,675)	$ (20,023)
Interest Rate Swap [Member] | Other Long-term Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivatives designated as cash flow hedges, liability derivatives	$ (32,406)

Summary of Significant Accou_13

Summary of Significant Accounting Policies (Impact of Cash Flow Hedges on Results of Operations, Comprehensive Income and Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized as AOCIL on Derivatives, Net of Tax	$ 17,116	$ (47,528)	$ (32,247)
Amount of Gain or (Loss) Recognized from AOCIL into Earnings, Net of Tax	(14,936)	(7,187)	5,900
Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized as AOCIL on Derivatives, Net of Tax	17,116	(47,528)	(32,247)
Amount of Gain or (Loss) Recognized from AOCIL into Earnings, Net of Tax	14,936	7,187	(5,900)
Cash Flow Hedging | Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized as AOCIL on Derivatives, Net of Tax	17,116	(47,528)	(32,247)
Cash Flow Hedging | Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized from AOCIL into Earnings, Net of Tax	$ 14,936	$ 7,187	$ (5,900)

Summary of Significant Accou_14

Summary of Significant Accounting Policies (Fair Value Assumptions) (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected remaining life	5 years
Progressive Waste Plans [Member] | Employee Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected remaining life	1 year		1 year 6 months
Share volatility	15.04%		16.14%
Share volatility, minimum		17.72%
Share volatility, maximum		33.54%
Discount rate	0.41%		1.61%
Annual dividend rate	0.68%	0.80%	0.82%
Minimum [Member] | Progressive Waste Plans [Member] | Employee Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected remaining life		6 months
Discount rate		0.06%
Maximum [Member] | Progressive Waste Plans [Member] | Employee Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected remaining life		1 year
Discount rate		0.12%

Prepaid Expenses and Other cu_3

Prepaid Expenses and Other current Assets (Schedule of Prepaid Expenses and Other Current Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Prepaid Expenses and Other Current Assets [Abstract]
Income taxes receivable	$ 61,305	$ 50,062
Inventory	44,257	36,729
Prepaid insurance	22,471	17,552
Prepaid licenses and permits	10,683	9,847
Other	37,006	46,524
Total prepaid expenses and other current assets	$ 175,722	$ 160,714

Property and Equipment, Net (Na

Property and Equipment, Net (Narrative) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Finance lease right-of-use assets	$ 10,342	$ 3,754
Landfill Site Costs [Member]
Property, Plant and Equipment [Line Items]
Landfill depletion expense	$ 212,898	$ 200,374	$ 225,687

Property and Equipment, Net (Pr

Property and Equipment, Net (Property and Equipment) (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and equipment gross	$ 10,276,878	$ 9,288,864
Less accumulated depreciation and depletion	(4,554,929)	(4,004,358)
Property and equipment net	5,721,949	5,284,506
Landfill Site Costs [Member]
Property, Plant and Equipment [Line Items]
Property and equipment gross	4,447,530	4,205,968
Rolling Stock [Member]
Property, Plant and Equipment [Line Items]
Property and equipment gross	2,483,294	2,227,951
Land, Buildings and Improvements
Property, Plant and Equipment [Line Items]
Property and equipment gross	1,339,542	1,147,358
Containers [Member]
Property, Plant and Equipment [Line Items]
Property and equipment gross	983,602	845,386
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment gross	940,723	820,533
Construction in Progress
Property, Plant and Equipment [Line Items]
Property and equipment gross	$ 82,187	$ 41,668

Intangible Assets, Net (Narrati

Intangible Assets, Net (Narrative) (Detail)	12 Months Ended
	Dec. 31, 2021
Long-term Franchise Agreements and Contracts
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average amortization period of acquired intangible assets	20 years 1 month 6 days
Customer Lists [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average amortization period of acquired intangible assets	11 years 7 months 6 days
Permits and Other [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average amortization period of acquired intangible assets	40 years

Intangible Assets, Net (Intangi

Intangible Assets, Net (Intangible Assets Exclusive of Goodwill) (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying amount	$ 1,973,656	$ 1,615,661
Finite-lived intangible assets, accumulated amortization	(823,743)	(696,269)
Intangible assets, accumulated impairment	(40,784)	(38,507)
Finite-lived intangible assets, net carrying amount	1,149,913	919,392
Intangible assets, net, exclusive of goodwill	1,350,597	1,155,079
Intangible assets, exclusive of goodwill	2,215,124	1,889,855
Indefinite-lived intangible assets, gross carrying amount	241,468	274,194
Indefinite-lived intangible assets	200,684	235,687
Solid Waste Collection and Transportation Permits
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Indefinite-lived intangible assets, gross carrying amount	181,613	172,056
Indefinite-lived intangible assets	181,613	172,056
Material Recycling Facility Permits
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Indefinite-lived intangible assets, gross carrying amount		42,283
Indefinite-lived intangible assets		42,283
Exploration and Production Facility Permits
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Intangible assets, accumulated impairment	(40,784)	(38,507)
Indefinite-lived intangible assets, gross carrying amount	59,855	59,855
Indefinite-lived intangible assets	19,071	21,348
Long-term Franchise Agreements and Contracts
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying amount	724,128	600,674
Finite-lived intangible assets, accumulated amortization	(278,827)	(234,972)
Finite-lived intangible assets, net carrying amount	445,301	365,702
Customer Lists [Member]
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying amount	711,047	636,035
Finite-lived intangible assets, accumulated amortization	(450,109)	(382,020)
Finite-lived intangible assets, net carrying amount	260,938	254,015
Permits and Other [Member]
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying amount	538,481	378,952
Finite-lived intangible assets, accumulated amortization	(94,807)	(79,277)
Finite-lived intangible assets, net carrying amount	$ 443,674	$ 299,675

Intangible Assets, Net (Estimat

Intangible Assets, Net (Estimated Future Amortization Expense of Amortizable Intangible Assets) (Detail) $ in Thousands	Dec. 31, 2021USD ($)
Intangible Assets, Net [Abstract]
For the year ending December 31, 2022	$ 137,771
For the year ending December 31, 2023	119,458
For the year ending December 31, 2024	103,820
For the year ending December 31, 2025	89,002
For the year ending December 31, 2026	$ 75,122

Acquisitions (Narrative) (Detai

Acquisitions (Narrative) (Details)	12 Months Ended
	Dec. 31, 2021USD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2021USD ($)entity	Dec. 31, 2021USD ($)agreement	Dec. 31, 2020USD ($)entity	Dec. 31, 2019USD ($)agreemententity
Business Acquisition [Line Items]
Cash consideration, net of cash acquired		$ 960,449,000			$ 388,789,000	$ 736,610,000
Contingent considerations	$ 31,616,000	31,616,000	$ 31,616,000	$ 31,616,000		14,038,000
Increase in contingent consideration		2,954,000			18,418,000	$ 1,498,000
Number of businesses acquired with contingent consideration | agreement				9		5
Acquisition related costs		11,318,000			9,803,000	$ 12,335,000
Payment of contingent consideration recorded at acquisition date		12,934,000			$ 12,566,000	$ 3,200,000
Number of individual businesses acquired in period | entity			30		21	21
Revenues		6,151,361,000			$ 5,445,990,000	$ 5,388,679,000
Income before income tax provision		770,742,000			253,914,000	705,891,000
Impairments and other operating items		32,316,000			466,718,000	61,948,000
Goodwill expected to be deductible for tax purposes	187,287,000	187,287,000	$ 187,287,000	$ 187,287,000	169,147,000	266,310,000
Trade receivables acquired in business combination gross contractual amount	36,645,000	36,645,000	36,645,000	36,645,000	13,854,000	27,297,000
Trade receivables acquired In business combination expected to be uncollectible amount	$ 3,409,000	$ 3,409,000	$ 3,409,000	$ 3,409,000	95,000	$ 2,077,000
Fair value of acquired working capital is provisional			19	19
Measurement Input, Discount Rate [Member]
Business Acquisition [Line Items]
Contingent consideration measurement input	1.5	1.5	1.5	1.5		2.3
Maximum [Member]
Business Acquisition [Line Items]
Contingent consideration payable period	2 years					4 years
Minimum [Member]
Business Acquisition [Line Items]
Contingent consideration payable period	1 year					1 year
Other Acquisition [Member]
Business Acquisition [Line Items]
Increase in contingent consideration					3,327,000
Debt [Member]
Business Acquisition [Line Items]
Liabilities incurred		$ 108,345,000			$ 91,349,000	$ 95,809,000

Acquisitions (Summary of Consid

Acquisitions (Summary of Consideration Transferred to Acquire Businesses and Amounts of Identifiable Assets Acquired, Liabilities Assumed and Noncontrolling Interests) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Fair value of consideration transferred:
Cash	$ 960,449	$ 388,789	$ 736,610
Change in open working capital settlements at year end		1,505	5,272
Consideration transferred	1,068,794	481,643	837,691
Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired:
Accounts receivable	33,236	13,759	25,220
Prepaid expenses and other current assets	4,866	4,509	4,970
Operating lease right-of-use assets	5,972	5,247	3,616
Property and equipment	394,687	173,394	294,037
Indefinite-lived intangibles	9,557	13,465
Other assets	77	389	7
Current portion of operating lease liabilities	(1,370)	(509)	(658)
Deferred revenue	(8,389)	(1,821)	(17,245)
Long-term portion of operating lease liablities	(4,602)	(4,738)	(2,958)
Other long-term liabilities	(13,976)	(2,136)	(8,707)
Deferred income taxes	(63,822)	(4,525)	(13,287)
Total identifiable net assets	614,199	296,340	430,623
Goodwill	454,595	185,303	407,068
Accounts Payable and Accrued Liabilities [Member]
Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired:
Accounts payable and accrued liabilities	(37,827)	(14,174)	(19,209)
Debt [Member]
Fair value of consideration transferred:
Liabilities incurred	108,345	91,349	95,809
Contingent Consideration [Member]
Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired:
Contingent consideration	(31,616)	(4,688)	(14,038)
Long-Term Franchise Agreements and Contracts [Member]
Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired:
Intangibles	134,827	59,149	78,312
Customer Lists [Member]
Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired:
Intangibles	75,612	48,512	52,422
Permits and Other [Member]
Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired:
Intangibles	$ 116,967	$ 10,507	$ 48,141

Leases (Narrative) (Details)

Leases (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating lease impairment charge	$ 0	$ 0	$ 0
Finance lease impairment charge	0	0	0
Remeasurements of lease	0	0	$ 0
Remeasurements of ROU assets	$ 10,012	$ 3,754

Leases (Leases) (Details)

Leases (Leases) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Lease cost for operating leases
Operating lease cost	$ 40,381	$ 39,411	$ 38,710
Amortization of leased assets	3,424
Interest on leased liabilities	152
Total lease cost	43,957	39,411	38,710
Operating cash flow information: Cash paid for amounts included in the measurement of lease liabilities	40,249	39,212	38,226
Operating cash flows from finance leases	152
Financing cash flows from finance leases	3,133
Right-of-use assets obtained in exchange for lease liabilities - operating leases	17,933	15,117	$ 17,774
Right-of-use assets obtained in exchange for lease liabilities - finance lease	$ 10,012	$ 3,754
Weighted average remaining lease term - operating leases	8 years	8 years 7 months 6 days	8 years 8 months 12 days
Weighted average remaining lease term - finance leases	4 years 10 months 24 days	5 years 4 months 24 days
Weighted average discount rate - operating leases	3.37%	3.86%	3.99%
Weighted average discount rate - finance leases	1.89%	1.89%

Leases (Future Minimum Lease Pa

Leases (Future Minimum Lease Payments) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Future minimum lease payments as calculated under the new lease guidance, operating leases
2022	$ 38,956
2023	34,060
2024	26,066
2025	19,310
2026	14,455
Thereafter	62,747
Minimum lease payments	195,594
Less: imputed interest	(27,949)
Present value of minimum lease payments, operating leases	167,645
Less: current portion of operating lease liabilities	(38,017)	$ (30,671)
Long-term portion of lease liabilities	129,628	147,223
Future minimum lease payments as calculated under the new lease guidance, finance leases
2022	2,162
2023	2,162
2024	2,162
2025	2,162
2026	2,161
Thereafter	234
Minimum lease payments	11,043
Less: imputed interest, finance leases	(524)
Present value of minimum lease payments, finance leases	$ 10,519	$ 3,754
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Long Term Debt Current, Long Term Debt Noncurrent	Long Term Debt Current, Long Term Debt Noncurrent
Less: current portion of finance lease liabilities	$ (2,061)
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Long Term Debt Current
Long-term portion of finance lease liabilities	$ 8,458
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Long Term Debt Noncurrent

Accrued Liabilities (Detail)

Accrued Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Accrued Liabilities [Abstract]
Insurance claims and premiums	$ 149,864	$ 147,188
Payroll and payroll-related	141,877	141,371
Interest payable	28,729	29,580
Final capping, closure and post-closure liability - current portion	19,925	19,925
Unrealized cash flow hedge losses	18,675	20,023
Property taxes	8,833	6,381
Cell processing reserve - current portion	3,364	3,344
Transaction-related expenses	3,130	3,304
Environmental remediation reserve - current portion	2,300	2,300
Share-based compensation plan liability - current portion	2,423	868
Other	63,476	30,639
Accrued liabilities	$ 442,596	$ 404,923

Long-Term Debt (Narrative) (Det

Long-Term Debt (Narrative) (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Sep. 20, 2021	Aug. 31, 2021	Mar. 13, 2020	Jan. 23, 2020	Apr. 16, 2019	Dec. 31, 2018	Nov. 16, 2018
Debt Instrument [Line Items]
Cash and equivalents	$ 147,441,000	$ 147,441,000	$ 617,294,000
Cash and cash equivalents	219,615,000	219,615,000	714,389,000	$ 423,221,000						$ 403,966,000
Loss on early extinguishment of debt		$ (115,288,000)
Credit Agreement [Member]
Debt Instrument [Line Items]
Maturity date		Jul. 30, 2026
Credit facility	2,500,000,000	$ 2,500,000,000
Covenant description		as of the last day of each fiscal quarter, the ratio of (a) Consolidated Total Funded Debt (as defined in the Credit Agreement) as of such date to (b) Consolidated EBITDA (as defined in the Credit Agreement), measured for the preceding 12 months, to not more than 3.75 to 1.00 (or 4.25 to 1.00 during material acquisition periods, subject to certain limitations).
Covenant compliance		As of December 31, 2021 and 2020, the Company was in compliance with all applicable covenants in the Credit Agreement as in effect as of the applicable date.
Credit Agreement [Member] | Letter of Credit [Member]
Debt Instrument [Line Items]
Letter of credit	112,281,000	$ 112,281,000	119,636,000
Credit facility	320,000,000	320,000,000
Credit Agreement [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility	1,850,000,000	1,850,000,000
Long term debt	803,944,000	$ 803,944,000	$ 203,927,000
Commitment - rate applicable		0.09%	0.15%
Credit Agreement [Member] | Term Loan Facility [Member]
Debt Instrument [Line Items]
Credit facility	$ 650,000,000	$ 650,000,000
Credit Agreement [Member] | Minimum [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Interest rate applicable	1.10%	1.10%
Commitment - rate applicable		0.065%
Credit Agreement [Member] | Maximum [Member]
Debt Instrument [Line Items]
Required leverage ratio during material acquisition period		4.25
Required leverage ratio		3.75
Credit Agreement [Member] | Maximum [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Interest rate applicable	3.25%	3.25%
Commitment - rate applicable		0.15%
Credit Agreement [Member] | Maximum [Member] | Swing Line Loans [Member]
Debt Instrument [Line Items]
Swing line loans	$ 100,000,000	$ 100,000,000
Other Facilities not Affiliated with Credit Agreement [Member] | Letter of Credit [Member]
Debt Instrument [Line Items]
Letter of credit	13,527,000	13,527,000
Notes Payable to Sellers and Other Third Parties [Member]
Debt Instrument [Line Items]
Long term debt	$ 37,508,000	$ 37,508,000	$ 43,131,000
Notes Payable to Sellers and Other Third Parties [Member] | Minimum [Member]
Debt Instrument [Line Items]
Interest rate	2.42%	2.42%
Senior note year due		2028
Notes Payable to Sellers and Other Third Parties [Member] | Maximum [Member]
Debt Instrument [Line Items]
Interest rate	10.35%	10.35%
Senior note year due		2036
Senior Notes [Member]
Debt Instrument [Line Items]
Percentage of aggregate principal amount to be repurchased if change of control		100.00%
Covenant compliance		As of December 31, 2021 and 2020, the Company was in compliance with all applicable covenants in the Indenture
Senior Notes [Member] | Maximum [Member]
Debt Instrument [Line Items]
Percentage of aggregate principal amount to be repurchased if change of control		101.00%
Senior Notes [Member] | Senior Notes due 2021 [Member]
Debt Instrument [Line Items]
Interest rate			4.64%
Maturity date		Apr. 1, 2021
Long term debt	$ 100,000,000	$ 100,000,000	$ 100,000,000
Senior note year due		2021
Senior Notes [Member] | New Senior Notes due 2021 [Member]
Debt Instrument [Line Items]
Interest rate			2.39%
Maturity date		Jun. 1, 2021
Long term debt			$ 150,000,000			$ 150,000,000
Senior note year due		2021
Senior Notes [Member] | Senior Notes due 2022 [Member]
Debt Instrument [Line Items]
Interest rate			3.09%
Maturity date		Aug. 20, 2022
Long term debt	125,000,000	$ 125,000,000	$ 125,000,000
Senior note year due		2022
Senior Notes [Member] | Senior Notes due 2023 [Member]
Debt Instrument [Line Items]
Interest rate			2.75%
Maturity date		Jun. 1, 2023
Long term debt	200,000,000	$ 200,000,000	$ 200,000,000
Senior note year due		2023
Senior Notes [Member] | Senior Notes due 2024 [Member]
Debt Instrument [Line Items]
Interest rate			3.24%
Maturity date		Apr. 20, 2024
Long term debt			$ 150,000,000			150,000,000
Senior note year due		2024
Senior Notes [Member] | Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Interest rate			3.41%
Maturity date		Aug. 20, 2025
Long term debt	$ 375,000,000	$ 375,000,000	$ 375,000,000
Senior note year due		2025
Senior Notes [Member] | Senior Notes due 2026 [Member]
Debt Instrument [Line Items]
Interest rate			3.03%
Maturity date		Jun. 1, 2026
Long term debt			$ 400,000,000			400,000,000
Senior note year due		2026
Senior Notes [Member] | Senior Notes due 2027 [Member]
Debt Instrument [Line Items]
Interest rate			3.49%
Maturity date		Apr. 20, 2027
Long term debt			$ 250,000,000			$ 250,000,000
Senior note year due		2027
Senior Notes [Member] | Senior Notes due 2028 [Member]
Debt Instrument [Line Items]
Aggregate principal amount											$ 500,000,000
Interest rate	4.25%	4.25%	4.25%
Maturity date		Dec. 1, 2028
Redemption period end date		Sep. 1, 2028
Debt issuance costs	$ 5,792,000	$ 5,792,000
Percentage of aggregate principal amount to be repurchased if change of control		100.00%
Long term debt	$ 500,000,000	$ 500,000,000	$ 500,000,000
Senior note year due		2028
Senior Notes [Member] | Senior Notes due 2029 [Member]
Debt Instrument [Line Items]
Aggregate principal amount									$ 500,000,000
Interest rate	3.50%	3.50%	3.50%
Maturity date		May 1, 2029
Redemption period end date		Feb. 1, 2029
Debt issuance costs	$ 5,954,000	$ 5,954,000
Long term debt	$ 500,000,000	$ 500,000,000	$ 500,000,000
Senior note year due		2029
Senior Notes [Member] | Senior Notes due 2029 [Member] | Minimum [Member]
Debt Instrument [Line Items]
Percentage of aggregate principal amount to be repurchased if change of control		100.00%
Senior Notes [Member] | Senior Notes due 2030 [Member]
Debt Instrument [Line Items]
Aggregate principal amount								$ 600,000,000
Interest rate	2.60%	2.60%	2.60%					2.60%
Maturity date		Feb. 1, 2030
Redemption period end date		Nov. 1, 2029
Debt issuance costs	$ 5,435,000	$ 5,435,000
Percentage of aggregate principal amount to be repurchased if change of control		100.00%
Long term debt	$ 600,000,000	$ 600,000,000	$ 600,000,000
Senior note year due		2030
Senior Notes [Member] | Senior Notes due 2032 [Member]
Debt Instrument [Line Items]
Aggregate principal amount					$ 650,000,000
Interest rate	2.20%	2.20%			2.20%
Maturity date		Jan. 15, 2032
Redemption period end date		Oct. 15, 2031
Debt discount	$ 1,066,000	$ 1,066,000
Debt issuance costs	$ 5,979,000	5,979,000
Percentage of aggregate principal amount to be repurchased if change of control	100.00%
Long term debt	$ 650,000,000	$ 650,000,000
Senior note year due		2032
Senior Notes [Member] | Senior Notes due 2050 [Member]
Debt Instrument [Line Items]
Aggregate principal amount							$ 500,000,000
Interest rate	3.05%	3.05%	3.05%
Maturity date		Apr. 1, 2050
Redemption period end date		Oct. 1, 2049
Debt discount	$ 7,375,000	$ 7,375,000
Debt issuance costs	5,682,000	$ 5,682,000
Percentage of aggregate principal amount to be repurchased if change of control		100.00%
Long term debt	$ 500,000,000	$ 500,000,000	$ 500,000,000
Senior note year due		2050
Senior Notes [Member] | Senior Notes due 2052 [Member]
Debt Instrument [Line Items]
Aggregate principal amount					$ 850,000
Interest rate	2.95%	2.95%			2.95%
Maturity date		Jan. 15, 2052
Redemption period end date		Jul. 15, 2051
Debt discount	$ 12,742,000	$ 12,742,000
Debt issuance costs	$ 9,732,000	9,732,000
Percentage of aggregate principal amount to be repurchased if change of control	100.00%
Long term debt	$ 850,000,000	$ 850,000,000
Senior note year due		2052
Senior Notes [Member] | Private Placement Notes [Member]
Debt Instrument [Line Items]
Redeemed aggregate principal amount of notes		$ 1,500,000,000
Senior Notes [Member] | Private Placement Notes Make Whole Payment [Member]
Debt Instrument [Line Items]
Redeemed aggregate principal amount of notes		110,617,000
Term Loan Facility [Member] | Credit Agreement [Member]
Debt Instrument [Line Items]
Long term debt	$ 650,000,000	$ 650,000,000	650,000,000
Interest rate applicable	1.10%	1.10%
Term Loan Facility [Member] | Credit Agreement [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility maximum increase to borrowing capacity		$ 500,000,000
Maximum amount of increase in commitments under the credit agreement		3,000,000,000
Other Assets [Member] | Credit Agreement [Member]
Debt Instrument [Line Items]
Prepaid expense, debt issuance costs	$ 3,711,000	3,711,000
Debt [Member]
Debt Instrument [Line Items]
Liabilities incurred		108,345,000	91,349,000	$ 95,809,000
Base Rate [Member] | Credit Agreement [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long term debt	$ 158,000,000	$ 158,000,000
Margin rate for loans		0.00%
Interest rate applicable	3.25%	3.25%
Base Rate [Member] | Canadian Prime Rate Loans and Swing Line Loans [Member] | Minimum [Member]
Debt Instrument [Line Items]
Margin rate for loans		0.00%
Base Rate [Member] | Canadian Prime Rate Loans and Swing Line Loans [Member] | Maximum [Member]
Debt Instrument [Line Items]
Margin rate for loans		0.25%
LIBOR [Member] | Credit Agreement [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long term debt	$ 631,000,000	$ 631,000,000	$ 200,000,000
Margin rate for loans		1.00%	1.20%
Interest rate applicable	1.10%	1.10%	1.35%
LIBOR [Member] | Credit Agreement [Member] | Term Loan Facility [Member]
Debt Instrument [Line Items]
Long term debt	$ 650,000,000	$ 650,000,000	$ 650,000,000
Margin rate for loans		1.00%	1.20%
Interest rate applicable	1.10%	1.10%	1.35%
LIBOR [Member] | Drawing Fees for Bankers Acceptance and BA Equivalent Notes and Letter of Credit [Member] | Minimum [Member]
Debt Instrument [Line Items]
Margin rate for loans		0.75%
LIBOR [Member] | Drawing Fees for Bankers Acceptance and BA Equivalent Notes and Letter of Credit [Member] | Maximum [Member]
Debt Instrument [Line Items]
Margin rate for loans		1.25%
LIBOR [Member] | Term Loan Facility [Member] | Credit Agreement [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long term debt	$ 1,281,000,000	$ 1,281,000,000
Canadian Bankers Acceptance Loan [Member] | Credit Agreement [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long term debt	$ 3,944,000	$ 3,944,000	$ 3,927,000
Margin rate for loans		1.00%	1.20%
Interest rate applicable	1.45%	1.45%	1.66%

Long-Term Debt (Long-Term Debt)

Long-Term Debt (Long-Term Debt) (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2021	Sep. 20, 2021	Aug. 31, 2021	Dec. 31, 2020	Jan. 23, 2020
Debt Instrument [Line Items]
Total debt and lease obligations	$ 5,101,971,000			$ 4,750,812,000
Less - current portion	(6,020,000)			(8,268,000)
Finance leases	10,519,000			3,754,000
Less - current portion	(6,020,000)			(8,268,000)
Less - unamortized debt discount and issuance costs	(55,451,000)			(33,866,000)
Long-term portion of debt and notes payable	5,040,500,000			4,708,678,000
Long-term debt and lease obligation	$ 5,040,500,000			4,708,678,000
Finance leases, expiration year	2027
Finance leases interest rate	1.89%
Credit Agreement [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long term debt	$ 803,944,000			203,927,000
Credit Agreement [Member] | Revolving Credit Facility [Member] | Minimum [Member]
Debt Instrument [Line Items]
Bearing interest	1.10%
Credit Agreement [Member] | Revolving Credit Facility [Member] | Maximum [Member]
Debt Instrument [Line Items]
Bearing interest	3.25%
Credit Agreement [Member] | Term Loan Facility [Member]
Debt Instrument [Line Items]
Long term debt	$ 650,000,000			650,000,000
Bearing interest	1.10%
Senior Notes due 2021 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long term debt	$ 100,000,000			$ 100,000,000
Interest rate				4.64%
Senior note year due	2021
New Senior Notes due 2021 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long term debt			$ 150,000,000	$ 150,000,000
Interest rate				2.39%
Senior note year due	2021
Senior Notes due 2022 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long term debt	$ 125,000,000			$ 125,000,000
Interest rate				3.09%
Senior note year due	2022
Senior Notes due 2023 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long term debt	$ 200,000,000			$ 200,000,000
Interest rate				2.75%
Senior note year due	2023
Senior Notes due 2024 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long term debt			150,000,000	$ 150,000,000
Interest rate				3.24%
Senior note year due	2024
Senior Notes due 2025 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long term debt	$ 375,000,000			$ 375,000,000
Interest rate				3.41%
Senior note year due	2025
Senior Notes due 2026 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long term debt			400,000,000	$ 400,000,000
Interest rate				3.03%
Senior note year due	2026
Senior Notes due 2027 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long term debt			$ 250,000,000	$ 250,000,000
Interest rate				3.49%
Senior note year due	2027
Senior Notes due 2028 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long term debt	$ 500,000,000			$ 500,000,000
Interest rate	4.25%			4.25%
Senior note year due	2028
Senior Notes due 2029 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long term debt	$ 500,000,000			$ 500,000,000
Interest rate	3.50%			3.50%
Senior note year due	2029
Senior Notes due 2030 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long term debt	$ 600,000,000			$ 600,000,000
Interest rate	2.60%			2.60%	2.60%
Senior note year due	2030
Senior Notes due 2032 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long term debt	$ 650,000,000
Interest rate	2.20%	2.20%
Senior note year due	2032
Senior Notes due 2050 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long term debt	$ 500,000,000			$ 500,000,000
Interest rate	3.05%			3.05%
Senior note year due	2050
Senior Notes due 2052 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long term debt	$ 850,000,000
Interest rate	2.95%	2.95%
Senior note year due	2052
Notes Payable to Sellers and Other Third Parties [Member]
Debt Instrument [Line Items]
Long term debt	$ 37,508,000			$ 43,131,000
Notes Payable to Sellers and Other Third Parties [Member] | Minimum [Member]
Debt Instrument [Line Items]
Interest rate	2.42%
Senior note year due	2028
Notes Payable to Sellers and Other Third Parties [Member] | Maximum [Member]
Debt Instrument [Line Items]
Interest rate	10.35%
Senior note year due	2036

Long-Term Debt (Details of the

Long-Term Debt (Details of the Company's Credit Agreement) (Details) - Credit Agreement [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Available	$ 933,775	$ 1,238,937
Commitment - rate applicable	0.09%	0.15%
Long-term Debt	$ 803,944	$ 203,927
US Swing Line Loan [Member]
Line of Credit Facility [Line Items]
Interest rate applicable	3.25%
Margin rate for loans	0.00%
Long-term Debt	$ 11,000
Letter of Credit [Member]
Line of Credit Facility [Line Items]
Letter of credit	$ 112,281	$ 119,636
Base Rate [Member] | Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Interest rate applicable	3.25%
Margin rate for loans	0.00%
Long-term Debt	$ 158,000
LIBOR [Member] | Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Interest rate applicable	1.10%	1.35%
Margin rate for loans	1.00%	1.20%
Long-term Debt	$ 631,000	$ 200,000
LIBOR [Member] | Term Loan Facility [Member]
Line of Credit Facility [Line Items]
Interest rate applicable	1.10%	1.35%
Margin rate for loans	1.00%	1.20%
Long-term Debt	$ 650,000	$ 650,000
Canadian Bankers Acceptance Loan [Member] | Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Interest rate applicable	1.45%	1.66%
Margin rate for loans	1.00%	1.20%
Long-term Debt	$ 3,944	$ 3,927

Long-Term Debt (Aggregate Contr

Long-Term Debt (Aggregate Contractual Future Principal Payments by Calendar Year on Long-Term Debt) (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Long-Term Debt [Abstract]
2022	$ 6,020
2023	6,090
2024	6,239
2025	6,391
2026	1,460,243
Thereafter	3,616,988
Total debt and lease obligations	$ 5,101,971	$ 4,750,812

Fair Value of Financial Instr_3

Fair Value of Financial Instruments (Assets and Liabilities Measured at Fair Value on Recurring Basis) (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Restricted cash	$ 72,174	$ 97,095
Contingent consideration	(31,616)		$ (14,038)
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Restricted cash	72,174	97,095
Restricted investments	58,797	58,181
Contingent consideration	(94,308)	(71,736)
Fair Value, Measurements, Recurring | Interest Rate Swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative instrument - net	(51,081)	(94,689)
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Restricted cash	72,174	97,095
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Restricted investments	58,797	58,181
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Interest Rate Swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative instrument - net	(51,081)	(94,689)
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration	$ (94,308)	$ (71,736)

Fair Value of Financial Instr_4

Fair Value of Financial Instruments (Fair Value for Level 3 Liabilities) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Fair Value of Financial Instruments [Abstract]
Beginning balance	$ 71,736	$ 69,484
Contingent consideration recorded at acquisition date	31,616	4,688
Payment of contingent consideration recorded at acquisition date	(12,934)	(12,566)
Payment of contingent consideration recorded in earnings	$ (520)	(10,371)
Fair value, location of contingent consideration recorded in earnings	Interest Expense
Adjustments to contingent consideration	$ 2,954	18,418	$ 1,498
Interest accretion expense	1,470	2,006
Foreign currency translation adjustment	(14)	77
Ending balance	$ 94,308	$ 71,736	$ 69,484

Commitments and Contingencies_2

Commitments and Contingencies (Narrative) (Detail) gal in Millions, T in Millions	Aug. 10, 2018USD ($)	Mar. 06, 2018USD ($)	Jul. 25, 2017USD ($)	Dec. 31, 2021USD ($)agreementTgal	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2014USD ($)
Contingencies And Commitments [Line Items]
Amount of surety bonds to secure asset closure and retirement requirements				$ 744,037,000	$ 727,361,000
Amount of surety bonds to secure performance under collection contracts and landfill operating agreements				$ 556,570,000	482,262,000
Percentage of interest in company that issues financial surety bonds				9.90%
Outstanding amount of financial surety bonds				$ 410,378,000	413,970,000
Purchase Obligation				100,220,000	93,813,000	$ 73,269,000
Environmental remediation reserve - current portion				2,300,000	2,300,000
Environmental remediation reserve-Non-current portion				$ 20,483,000	$ 19,121,000
Unrecorded unconditional purchase obligation, remaining volume | gal				60
Purchase commitment				$ 151,733,000
Minimum required threshold for disclosing environmental matters involving potential monetary sanctions				300,000
Threshold used for disclosing environmental matters involving potential monetary sanctions				$ 1,000,000
Number of collective bargaining agreements expired or set to expire | agreement				22
Estimated clean up costs							$ 342,000,000
Bridge and Thoroughfare Fee [Member]
Contingencies And Commitments [Line Items]
Loss contingency amount sought		$ 83,000	$ 11,600,000
Noncompliance fee		$ 750
Chiquita Canyon LLC [Member]
Contingencies And Commitments [Line Items]
Annual tons of waste accepted at landfill | T				2.5
Estimate of total new fees and other new taxes over life of conditional use permit				$ 300,000,000
Environmental Remediation Expense
Contingencies And Commitments [Line Items]
Estimated period to implement clean-up				seven years
Required period of monitoring following the clean-up				10 years
Penalties [Member] | Bridge and Thoroughfare Fee [Member]
Contingencies And Commitments [Line Items]
Fee paid	$ 83,000
Monthly payment estimate	83,000
Fees [Member] | Bridge and Thoroughfare Fee [Member]
Contingencies And Commitments [Line Items]
Fee paid	750
Monthly payment estimate	$ 750

Commitments and Contingencies_3

Commitments and Contingencies (Future Minimum Purchase Commitments) (Details) $ in Thousands	Dec. 31, 2021USD ($)
Commitments and Contingencies [Abstract]
2022	$ 98,655
2023	51,289
2024	1,789
Total purchase commitment	$ 151,733

Shareholders' Equity (Narrative

Shareholders' Equity (Narrative) (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		5 Months Ended	6 Months Ended	12 Months Ended			67 Months Ended
	Oct. 31, 2021	Sep. 30, 2021	Dec. 31, 2021	Jul. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2021	Jul. 27, 2021	Jun. 01, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Repurchase of common shares					3,003,822	1,271,977	0
Aggregate cost of common shares repurchase					$ 338,993	$ 105,654
Aggregate cost of common stock repurchase
Cash dividend per share	$ 0.23	$ 0.205			$ 0.845	$ 0.760	$ 0.665
Cash dividend per common share, increase	$ 0.025
Cash dividends on common stock					$ 220,203	$ 199,883	$ 175,067
Maximum remaining number of shares available for repurchase			12,768,063		12,768,063			12,768,063
Maximum number of shares authorized for repurchase									13,025,895
Share repurchase plan expiration date			Aug. 9, 2022
Daily repurchase of shares maximum				75,704
Daily Shares Repurchase (as percentage)			25.00%		25.00%			25.00%
Average daily trading volume during period				302,816
Common shares, shares issued			260,283,158		260,283,158	262,899,174		260,283,158
Preferred stock, shares issued			0		0	0	0	0
Issuance of shares under employee share purchase plan, shares					10,813
Issuance of shares under employee share purchase plan					$ 1,222
Employee Share Purchase Plan 2020 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum percent of eligible compensation to purchase shares			1.00%		1.00%			1.00%
Maximum percent of eligible compensation to purchase shares			10.00%		10.00%			10.00%
Maximum number of share authorized to be issued under plan			1,000,000		1,000,000			1,000,000
2016 Incentive Award Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of share authorized to be issued under plan			7,500,000		7,500,000			7,500,000
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant expiration					2022
Minimum [Member] | Employee Share Purchase Plan 2020 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price percentage of closing price of common share					85.00%
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant expiration					2026
Maximum [Member] | Employee Share Purchase Plan 2020 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price percentage of closing price of common share					95.00%
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested deferred RSUs outstanding			100,861		100,861	177,760	247,999	100,861
Restricted Stock Units (RSUs) [Member] | 2004 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted in period					0	0	0
Restricted Stock Units (RSUs) [Member] | Progressive Waste Solutions Ltd. [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted in period								0
Performance Shares [Member] | 2019 Performance Based Restricted Share Units Plan One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award							3 years
Performance period end date							Dec. 31, 2021
Performance Shares [Member] | 2019 Performance-Based Restricted Share Units Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award							3 years
Performance Shares [Member] | 2021 Performance Based Restricted Share Units Plan One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award					3 years
Performance period end date					Dec. 31, 2023
Performance Shares [Member] | 2020 Performance Based Restricted Share Units Plan One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award						3 years
Performance period end date						Dec. 31, 2022
Performance Shares [Member] | 2020 Performance Based Restricted Share Units Plan Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award						3 years
Performance Shares [Member] | Minimum [Member] | 2019 Performance-Based Restricted Share Units Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award							1 year
Performance Shares [Member] | Minimum [Member] | 2020 Performance Based Restricted Share Units Plan Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award						1 year
Performance Shares [Member] | Maximum [Member] | 2019 Performance-Based Restricted Share Units Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award							4 years
Performance Shares [Member] | Maximum [Member] | 2020 Performance Based Restricted Share Units Plan Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award						4 years
Special Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares, shares issued			0		0	0	0	0
Deferred Share Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested deferred RSUs outstanding			24,442		24,442	21,586		24,442
Restricted Share Units and Deferred Share Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Sale of common shares held in trust, shares					3,522	7,330	48,375
Restricted Share Units and Deferred Share Units [Member] | Progressive Waste Solutions Ltd. [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Acquired common shares held in trust			70,662		70,662			70,662		735,171
Progressive Waste Solutions Ltd. [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested deferred RSUs outstanding			63,032		63,032	66,554		63,032
Progressive Waste Solutions Ltd. [Member] | Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option awards granted in period								0

Shareholders' Equity (Common St

Shareholders' Equity (Common Stock Shares Reserved for Issuances) (Detail)	Dec. 31, 2021shares
Class Of Stock [Line Items]
Shares reserved for issuance	6,988,662
Restricted Stock Units Performance Share Units and Warrants [Member]
Class Of Stock [Line Items]
Shares reserved for issuance	1,933,004
2016 Incentive Award Plan [Member]
Class Of Stock [Line Items]
Shares reserved for issuance	4,066,471
Employee Share Purchase Plan 2020 [Member]
Class Of Stock [Line Items]
Shares reserved for issuance	989,187

Shareholders' Equity (Restricte

Shareholders' Equity (Restricted Stock Units Activity) (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Restricted Stock Units (RSUs) [Member]
Schedule of Share based Compensation Arrangements by Share based Payment Award, Equity Instruments, Other Than Options, Restricted Stock Units [Line Items]
Stock units granted	498,078
Weighted average grant-date fair value of award	$ 100.27	$ 101.79	$ 81.24
Total fair value of share units vested	$ 26,711	$ 23,742	$ 21,136
Performance Shares [Member]
Schedule of Share based Compensation Arrangements by Share based Payment Award, Equity Instruments, Other Than Options, Restricted Stock Units [Line Items]
Stock units granted	116,784
Weighted average grant-date fair value of award	$ 96.99	$ 87.19	$ 80.85
Total fair value of share units vested	$ 10,954	$ 15,628	$ 7,683
Deferred Share Units [Member]
Schedule of Share based Compensation Arrangements by Share based Payment Award, Equity Instruments, Other Than Options, Restricted Stock Units [Line Items]
Stock units granted	2,856
Weighted average grant-date fair value of award	$ 99.80	$ 103.81	$ 83.80
Total fair value of share units awarded	$ 285	$ 272	$ 319

Shareholders' Equity (Summary o

Shareholders' Equity (Summary of Activity Related to Restricted Stock Units) (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Restricted Stock Units (RSUs) [Member]
Unvested shares
Outstanding shares beginning balance	177,760	247,999
Outstanding, shares beginning balance	772,625
Granted	498,078
Forfeited	(65,528)
Vested and issued	343,480
Outstanding, shares ending balance	100,861	177,760	247,999
Outstanding, shares, ending balance	861,695	772,625
Weighted-Average Grant Date Fair Value Per Share
Outstanding, beginning balance	$ 84.61
Granted	100.27	$ 101.79	$ 81.24
Forfeited	94.63
Vested and Issued	77.76
Outstanding, ending balance	$ 95.63	$ 84.61
Performance Shares [Member]
Unvested shares
Outstanding, shares beginning balance	434,558
Granted	116,784
Forfeited	(5,048)
Vested and issued	154,251
Outstanding, shares, ending balance	392,043	434,558
Weighted-Average Grant Date Fair Value Per Share
Outstanding, beginning balance	$ 82.60
Granted	96.99	$ 87.19	80.85
Forfeited	68.58
Vested and Issued	71.01
Outstanding, ending balance	$ 91.63	$ 82.60
Deferred Share Units [Member]
Unvested shares
Outstanding shares beginning balance	21,586
Granted	2,856
Outstanding, shares ending balance	24,442	21,586
Weighted-Average Grant Date Fair Value Per Share
Outstanding, beginning balance	$ 59.32
Granted	99.80	$ 103.81	$ 83.80
Outstanding, ending balance	$ 64.05	$ 59.32
Progressive Waste Solutions Ltd. [Member] | Restricted Stock Units (RSUs) [Member]
Unvested shares
Outstanding shares beginning balance	66,554
Cash settled	(3,522)
Outstanding, shares ending balance	63,032	66,554

Shareholders' Equity (Summary_2

Shareholders' Equity (Summary of Warrant Activity) (Detail) - Stock Purchase Warrants	12 Months Ended
	Dec. 31, 2021$ / sharesshares
Warrant
Outstanding shares beginning balance | shares	489,748
Granted | shares	218,166
Forfeited | shares	(82,779)
Exercised | shares	(46,730)
Outstanding, shares ending balance | shares	578,405
Weighed Average Exercise Price
Outstanding beginning balance | $ / shares	$ 86.41
Granted | $ / shares	110.91
Forfeited | $ / shares	81.35
Exercised | $ / shares	72.88
Outstanding ending balance | $ / shares	$ 104.82

Shareholders' Equity (Summarize

Shareholders' Equity (Summarized Information about Warrants Outstanding) (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Class of Warrant or Right [Line Items]
Outstanding, ending balance	578,405	489,748
Stock Purchase Warrants 2016 Issuance [Member]
Class of Warrant or Right [Line Items]
Grant date	2016
Warrants issued	15,666
Exercise price, lower limit	$ 42.22
Exercise price, upper limit	$ 51.55
Fair value of warrants issued	$ 189
Outstanding, ending balance		7,158
Stock Purchase Warrants 2017 Issuance [Member]
Class of Warrant or Right [Line Items]
Grant date	2017
Warrants issued	35,382
Exercise price, lower limit	$ 53.65
Exercise price, upper limit	$ 69.96
Fair value of warrants issued	$ 595
Outstanding, ending balance	1,521	33,551
Stock Purchase Warrants 2018 Issuance [Member]
Class of Warrant or Right [Line Items]
Grant date	2018
Warrants issued	163,995
Exercise price, lower limit	$ 70.91
Exercise price, upper limit	$ 80.90
Fair value of warrants issued	$ 2,591
Outstanding, ending balance	112,756	133,141
Stock Purchase Warrants 2019 Issuance [Member]
Class of Warrant or Right [Line Items]
Grant date	2019
Warrants issued	151,008
Exercise price, lower limit	$ 74.25
Exercise price, upper limit	$ 95.61
Fair value of warrants issued	$ 2,634
Outstanding, ending balance	101,977	151,008
Stock Purchase Warrants 2021 Issuance [Member]
Class of Warrant or Right [Line Items]
Grant date	2021
Warrants issued	218,166
Exercise price, lower limit	$ 99.33
Exercise price, upper limit	$ 135.97
Fair value of warrants issued	$ 5,584
Outstanding, ending balance	215,765
Stock Purchase Warrants 2020 Issuance [Member]
Class of Warrant or Right [Line Items]
Grant date	2020
Warrants issued	164,890
Exercise price, lower limit	$ 72.65
Exercise price, upper limit	$ 104.89
Fair value of warrants issued	$ 3,140
Outstanding, ending balance	146,386	164,890

Shareholders' Equity (Summary_3

Shareholders' Equity (Summary of Vesting Activity Related to Restricted Share Units) (Details)	12 Months Ended
	Dec. 31, 2021shares
Restricted Stock Units (RSUs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Forfeited	(65,528)
Restricted Stock Units (RSUs) [Member] | Progressive Waste Solutions Ltd. [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Cash settled	(3,522)
Performance Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Forfeited	(5,048)

Shareholders' Equity (Summary_4

Shareholders' Equity (Summary of Stock Option Activity and Related Information) (Detail) - Progressive Waste Solutions Ltd. [Member]	12 Months Ended
	Dec. 31, 2021shares
Number of Shares (Options)
Outstanding, shares beginning balance	51,200
Cash settled	(5,331)
Outstanding, shares ending balance	45,869

Other Comprehensive Income (L_3

Other Comprehensive Income (Loss) (Components of Other Comprehensive Income (Loss)) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amount of Gain or (Loss) Recognized from AOCIL into Earnings, Net of Tax	$ (14,936)	$ (7,187)	$ 5,900
Amount of Gain or (Loss) Recognized as AOCIL on Derivatives, Net of Tax	17,116	(47,528)	(32,247)
Foreign currency translation adjustment, gross	8,183	50,653	101,970
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Total	8,183	50,653	101,970
Other Comprehensive Income (Loss), before Tax	51,791	(4,233)	50,070
Other Comprehensive Income (Loss), Tax	11,556	(14,545)	(13,753)
Other comprehensive income (loss), net of tax	40,235	10,312	63,823
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amount of Gain or (Loss) Recognized from AOCIL into Earnings, Net of Tax	(14,936)	(7,187)	5,900
Amount of Gain or (Loss) Recognized as AOCIL on Derivatives, Net of Tax	17,116	(47,528)	(32,247)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Total	8,183	50,653	101,970
Interest Rate Swap [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	20,321	9,778	(8,027)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax	(5,385)	(2,591)	2,127
Amount of Gain or (Loss) Recognized from AOCIL into Earnings, Net of Tax	14,936	7,187	(5,900)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax	23,287	(64,664)	(43,873)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, Tax	(6,171)	17,136	11,626
Amount of Gain or (Loss) Recognized as AOCIL on Derivatives, Net of Tax	$ 17,116	$ (47,528)	$ (32,247)

Other Comprehensive Income (L_4

Other Comprehensive Income (Loss) (Amounts Included in Accumulated Other Comprehensive Income (Loss)) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Components of Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity Attributable to Parent, Beginning Balance	$ 6,859,273
Foreign currency translation adjustment	8,183	$ 50,653	$ 101,970
Stockholders' Equity Attributable to Parent, Ending Balance	6,988,938	6,859,273
Accumulated Other Comprehensive Income (Loss) [Member]
Components of Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity Attributable to Parent, Beginning Balance	(651)	(10,963)
Amounts reclassified into earnings	14,936	7,187
Change in fair value	17,116	(47,528)
Foreign currency translation adjustment	8,183	50,653	101,970
Stockholders' Equity Attributable to Parent, Ending Balance	39,584	(651)	(10,963)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member] | Interest Rate Swap [Member]
Components of Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity Attributable to Parent, Beginning Balance	(69,596)	(29,255)
Amounts reclassified into earnings	14,936	7,187
Change in fair value	17,116	(47,528)
Stockholders' Equity Attributable to Parent, Ending Balance	(37,544)	(69,596)	(29,255)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member] | Foreign Currency Translation Adjustment [Member]
Components of Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity Attributable to Parent, Beginning Balance	68,945	18,292
Foreign currency translation adjustment	8,183	50,653
Stockholders' Equity Attributable to Parent, Ending Balance	$ 77,128	$ 68,945	$ 18,292

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating Loss Carryforwards [Line Items]
Statutory income tax rate	21.00%	21.00%	21.00%
Inter-entity payments expense		$ 27,358
Deferred income tax expense		4,148
Non-deductible expenses, other			$ 3,805
Unrecognized tax benefits	$ 0	$ 0	$ 0
Deferred tax liabilities, undistributed earnings	1,685,889
Deferred tax liability not recognized, undistributed earnings of foreign subsidiaries	340,308
Undistributed earnings	$ 2,860,889
Canada Revenue Agency [Member]
Operating Loss Carryforwards [Line Items]
Foreign Statutory income tax rate	27.00%
Operating loss carryforwards	$ 47,966

Income Taxes (Income (Loss) Bef

Income Taxes (Income (Loss) Before Provision (Benefit) for Income Taxes) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Taxes [Abstract]
U.S.	$ 574,737	$ 22,349	$ 477,203
Non-U.S.	196,005	231,565	228,688
Income before income tax provision	$ 770,742	$ 253,914	$ 705,891

Income Taxes (Provision Benefit

Income Taxes (Provision Benefit for Income Taxes) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Current:
U.S. Federal	$ 71,180	$ 65,143	$ 45,475
State	34,439	28,325	27,528
Non - U.S.	32,071	6,941	11,570
Current income tax expense (benefit), total	137,690	100,409	84,573
Deferred:
U.S. Federal	51,534	(36,659)	58,291
State	5,093	(8,762)	6,331
Non - U.S.	(42,064)	(5,066)	(9,985)
Deferred income tax expense (benefit), total	14,563	(50,487)	54,637
Provision (benefit) for income taxes	$ 152,253	$ 49,922	$ 139,210

Income Taxes (Differences betwe

Income Taxes (Differences between Income Tax Provision in Statements of Net Income and Income Tax Provision Computed at Federal Statutory Rate) (Detail)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Taxes [Abstract]
U.S. federal statutory rate	21.00%	21.00%	21.00%
State taxes, net of federal benefit	4.70%	4.50%	4.40%
Deferred income tax liability adjustments	0.30%	1.60%	0.60%
Effect of international operations	(6.30%)	(7.00%)	(6.30%)
Other	0.10%	(0.40%)
Effective income tax rate, total	19.80%	19.70%	19.70%

Income Taxes (Significant Compo

Income Taxes (Significant Components of Deferred Income Tax Assets and Liabilities) (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred income tax assets:
Accrued expenses	$ 31,840	$ 26,600
Compensation	22,545	18,150
Contingent liabilities	21,268	17,652
Tax credits and loss carryforwards	24,415	24,044
Interest rate and fuel hedges	13,536	25,093
Finance costs	24,264
Other		872
Gross deferred income tax assets	137,868	112,411
Less: Valuation allowance
Total deferred income tax assets	137,868	112,411
Deferred income tax liabilities:
Goodwill and other intangibles	(397,855)	(332,097)
Property and equipment	(484,519)	(440,019)
Landfill closure/post-closure	(18,597)	(13,846)
Prepaid expenses	(11,534)	(14,990)
Investment in subsidiaries	(69,286)	(69,391)
Finance costs		(2,112)
Other	(6,998)
Total deferred income tax liabilities	(988,789)	(872,455)
Net deferred income tax liability	$ (850,921)	$ (760,044)

Segment Reporting (Narrative) (

Segment Reporting (Narrative) (Detail) - segment	12 Months Ended			24 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020
Segment Reporting [Abstract]
Number of major customers	0
Number of geographic operating segments	5	5	5	5
Number of operating segments	5
Number of reportable segments	5

Segment Reporting (Summary of F

Segment Reporting (Summary of Financial Information Concerning Company's Reportable Segments) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Revenue	$ 6,151,361	$ 5,445,990	$ 5,388,679
Segment EBITDA	1,884,950	1,631,550	1,643,644
Depreciation and amortization	813,009	752,404	743,918
Capital expenditures	744,315	664,561	666,089
Total assets	14,699,924	13,992,364	13,737,695
Intercompany Revenues [Member]
Segment Reporting Information [Line Items]
Revenue	(878,654)	(814,397)	(787,994)
Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	7,030,015	6,260,387	6,176,673
Segment EBITDA	1,904,546	1,646,833	1,659,082
Eastern [Member]
Segment Reporting Information [Line Items]
Revenue	1,521,288	1,335,865	1,268,964
Segment EBITDA	404,493	343,446	330,578
Depreciation and amortization	239,130	222,934	204,221
Capital expenditures	174,350	181,787	154,218
Total assets	3,652,311	3,134,462	3,099,283
Eastern [Member] | Intercompany Revenues [Member]
Segment Reporting Information [Line Items]
Revenue	(286,275)	(266,115)	(255,684)
Eastern [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	1,807,563	1,601,980	1,524,648
Segment EBITDA	404,493
Southern [Member]
Segment Reporting Information [Line Items]
Revenue	1,446,746	1,369,580	1,449,000
Segment EBITDA	394,982	369,445	441,425
Depreciation and amortization	188,977	189,726	208,967
Capital expenditures	156,527	131,831	178,127
Total assets	3,513,355	3,402,081	3,952,449
Southern [Member] | Intercompany Revenues [Member]
Segment Reporting Information [Line Items]
Revenue	(186,656)	(183,107)	(174,614)
Southern [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	1,633,402	1,552,687	1,623,614
Western [Member]
Segment Reporting Information [Line Items]
Revenue	1,280,188	1,149,762	1,098,849
Segment EBITDA	405,778	364,790	338,563
Depreciation and amortization	129,988	115,151	102,067
Capital expenditures	152,149	132,344	147,893
Total assets	2,260,222	1,861,079	1,718,015
Western [Member] | Intercompany Revenues [Member]
Segment Reporting Information [Line Items]
Revenue	(154,656)	(142,120)	(135,820)
Western [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	1,434,844	1,291,882	1,234,669
Segment EBITDA	405,778
Central [Member]
Segment Reporting Information [Line Items]
Revenue	1,046,416	880,323	838,584
Segment EBITDA	359,434	313,033	292,111
Depreciation and amortization	134,078	113,004	106,391
Capital expenditures	144,458	102,966	116,831
Total assets	2,332,564	2,160,246	1,885,468
Central [Member] | Intercompany Revenues [Member]
Segment Reporting Information [Line Items]
Revenue	(142,085)	(127,758)	(119,555)
Central [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	1,188,501	1,008,081	958,139
Segment EBITDA	359,434
Canada Segment [Member]
Segment Reporting Information [Line Items]
Revenue	856,723	710,460	733,282
Segment EBITDA	339,859	256,119	256,405
Depreciation and amortization	111,458	103,334	113,944
Capital expenditures	68,183	109,886	61,119
Total assets	2,513,608	2,544,379	2,490,291
Canada Segment [Member] | Intercompany Revenues [Member]
Segment Reporting Information [Line Items]
Revenue	(108,982)	(95,297)	(102,321)
Canada Segment [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	965,705	805,757	835,603
Segment EBITDA	339,859
Corporate [Member]
Segment Reporting Information [Line Items]
Segment EBITDA	(19,596)	(15,283)	(15,438)
Depreciation and amortization	9,378	8,255	8,328
Capital expenditures	48,648	5,747	7,901
Total assets	$ 427,864	$ 890,117	$ 592,189

Segment Reporting (Changes in G

Segment Reporting (Changes in Goodwill by Reportable Segment) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 5,726,650	$ 5,510,851
Goodwill acquired	454,597	185,303
Goodwill acquisition adjustments	2
Goodwill divested	(324)	(149)
Impact of changes in foreign currency	6,722	30,645
Goodwill, Ending Balance	6,187,643	5,726,650
Southern [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	1,532,215	1,528,225
Goodwill acquired	56,576	3,990
Goodwill divested	(324)
Goodwill, Ending Balance	1,588,467	1,532,215
Eastern [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	1,374,577	1,331,180
Goodwill acquired	233,146	43,397
Goodwill, Ending Balance	1,607,723	1,374,577
Western [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	442,862	400,037
Goodwill acquired	96,870	42,825
Goodwill, Ending Balance	539,732	442,862
Central [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	824,204	729,470
Goodwill acquired	68,005	94,883
Goodwill divested		(149)
Goodwill, Ending Balance	892,209	824,204
Canada Segment [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	1,552,792	1,521,939
Goodwill acquired		208
Goodwill acquisition adjustments	2
Impact of changes in foreign currency	6,722	30,645
Goodwill, Ending Balance	1,559,512	1,552,792
Exploration and Production [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 0	0
Goodwill, Ending Balance		$ 0

Segment Reporting (Property and

Segment Reporting (Property and Equipment, Net Relating to Operations) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Property and equipment	$ 5,721,949	$ 5,284,506
United States [Member]
Segment Reporting Information [Line Items]
Property and equipment	5,075,184	4,589,144
Canada [Member]
Segment Reporting Information [Line Items]
Property and equipment	$ 646,765	$ 695,362

Segment Reporting (Reconciliati

Segment Reporting (Reconciliation of Primary Measure of Segment Profitability to Income before Income Tax Provision) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Segment EBITDA	$ 1,884,950	$ 1,631,550	$ 1,643,644
Depreciation	(673,730)	(621,102)	(618,396)
Amortization of intangibles	(139,279)	(131,302)	(125,522)
Impairments and other operating items	(32,316)	(466,718)	(61,948)
Interest expense	(162,796)	(162,375)	(147,368)
Interest income	2,916	5,253	9,777
Other income (expense), net	6,285	(1,392)	5,704
Loss on early extinguishment of debt	(115,288)
Income before income tax provision	770,742	253,914	705,891
Operating Segments [Member]
Segment EBITDA	1,904,546	1,646,833	1,659,082
Southern [Member]
Segment EBITDA	394,982	369,445	441,425
Eastern [Member]
Segment EBITDA	404,493	343,446	330,578
Eastern [Member] | Operating Segments [Member]
Segment EBITDA	404,493
Western [Member]
Segment EBITDA	405,778	364,790	338,563
Western [Member] | Operating Segments [Member]
Segment EBITDA	405,778
Canada Segment [Member]
Segment EBITDA	339,859	256,119	256,405
Canada Segment [Member] | Operating Segments [Member]
Segment EBITDA	339,859
Central [Member]
Segment EBITDA	359,434	313,033	292,111
Central [Member] | Operating Segments [Member]
Segment EBITDA	359,434
Corporate [Member]
Segment EBITDA	$ (19,596)	$ (15,283)	$ (15,438)

Net Income Per Share Informat_3

Net Income Per Share Information (Basic and Diluted Net Income Per Common Share) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Numerator:
Net income attributable to Waste Connections for basic and diluted earnings per share	$ 618,047	$ 204,677	$ 566,841
Denominator:
Basic shares outstanding	261,166,723	263,189,699	263,792,693
Dilutive effect of equity-based awards	561,747	497,840	733,868
Diluted shares outstanding	261,728,470	263,687,539	264,526,561

Employee Benefit Plans (Narrati

Employee Benefit Plans (Narrative) (Detail) $ in Thousands	2 Months Ended	3 Months Ended	12 Months Ended
	May 31, 2020	Mar. 31, 2020	Dec. 31, 2021USD ($)agreement	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Employee Benefit Plan [Line Items]
Percentage of every dollar of a participating employee's pre-tax contributions as matching contribution to 401(k) Plan			100.00%
Number of multiemployer pension plans | agreement			15
Deferred Compensation Plan [Member]
Employee Benefit Plan [Line Items]
Percentage of every dollar of a participating employee's pre-tax contributions as matching contribution to 401(k) Plan	100.00%	100.00%	100.00%		100.00%
Percentage of employee's eligible compensation that represents the maximum amount of employer matching contribution to plan	5.00%	5.00%	5.00%		5.00%
Percentage of salary that may voluntarily be elected to be deferred			80.00%
Percentage of bonuses, commissions and restricted share unit grants that may voluntarily be elected to be deferred			100.00%
Total liability for deferred compensation			$ 50,738	$ 43,069
Voluntary Savings And Investment Plan
Employee Benefit Plan [Line Items]
Total employer expenses, including employer matching contributions			$ 31,834	$ 16,350	$ 26,111
Maximum [Member]
Employee Benefit Plan [Line Items]
Percentage of employee's eligible compensation that represents the maximum amount of employer matching contribution to plan			5.00%
Maximum [Member] | Retirement Savings Plan [Member]
Employee Benefit Plan [Line Items]
Contribution to a deferred profit sharing plan			5.00%

Employee Benefit Plans (Plan Co

Employee Benefit Plans (Plan Contributions) (Details) - USD ($) $ in Thousands	Apr. 30, 2020	Apr. 30, 2018	Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Multiemployer Plans [Line Items]
Company contributions					$ 15,251		$ 14,592		$ 14,110
Local 731 I b Of T Pension Fund [Member]
Multiemployer Plans [Line Items]
Registration number					36-6513567 - 001
Pension Protection Act zone status			Green					Green
FIP/RP status					NA
Company contributions					$ 4,504		$ 4,628		4,570
Collective-bargaining agreement, expiration date					Sep. 30, 2023
Western Conference of Teamsters Pension Trust [Member]
Multiemployer Plans [Line Items]
Registration number					91-6145047 - 001
Pension Protection Act zone status					Green		Green
FIP/RP status					NA
Company contributions					$ 4,963		$ 4,841		4,550
International Union of Operating Engineers Pension Trust [Member]
Multiemployer Plans [Line Items]
Registration number					85512-1
Pension Protection Act zone status	Green	Green
FIP/RP status					NA
Company contributions					$ 295		$ 279		238
Multi-Sector Pension Plan [Member]
Multiemployer Plans [Line Items]
Registration number					1085653
Pension Protection Act zone status					Green		Green
FIP/RP status					NA
Company contributions					$ 265		$ 196		202
Collective-bargaining agreement, expiration date					Dec. 31, 2023
Midwest Operating Engineers Pension Plan [Member]
Multiemployer Plans [Line Items]
Registration number					36-6140097 - 001
Pension Protection Act zone status				Green		Green
FIP/RP status					NA
Company contributions					$ 424		$ 316		339
Collective-bargaining agreement, expiration date					Oct. 31, 2025
Locals 302 & 612 of the IOUE - Employers Construction Industry Retirement Plan [Member]
Multiemployer Plans [Line Items]
Registration number					91-6028571 - 001
Pension Protection Act zone status					Green		Green
FIP/RP status					NA
Company contributions					$ 313		$ 298		290
Collective-bargaining agreement, expiration date					Nov. 16, 2022
Suburban Teamsters of Northern Illinois Pension Fund [Member]
Multiemployer Plans [Line Items]
Registration number					36-6155778 - 001
Pension Protection Act zone status					Green		Green
FIP/RP status					NA
Company contributions					$ 2,300		$ 2,080		1,844
Collective-bargaining agreement, expiration date					Feb. 29, 2024
Teamster Local 301 Pension Fund [Member]
Multiemployer Plans [Line Items]
Registration number					36-6492992 - 001
Pension Protection Act zone status					Green		Green
FIP/RP status					NA
Company contributions					$ 841		$ 673		624
Collective-bargaining agreement, expiration date					Sep. 30, 2023
Automobile Mechanics' Local No. 701 Union and Industry Pension Fund [Member]
Multiemployer Plans [Line Items]
Registration number					36-6042061 - 001
Pension Protection Act zone status					Green		Green
FIP/RP status					NA
Company contributions					$ 439		$ 457		492
Collective-bargaining agreement, expiration date					Dec. 31, 2022
IAM National Pension Fund [Member]
Multiemployer Plans [Line Items]
Registration number					51-6031295 - 002
Pension Protection Act zone status					Red		Red
FIP/RP status					NA
Company contributions					$ 299		$ 310		256
Collective-bargaining agreement, expiration date					Dec. 31, 2022
Local 813 Pension Trust Fund [Member]
Multiemployer Plans [Line Items]
Registration number					13-1975659 - 001
Pension Protection Act zone status					Red		Red
FIP/RP status					Implemented
Company contributions					$ 258		$ 183		281
Collective-bargaining agreement, expiration date					Nov. 30, 2022
Recycling and General Industrial Union Local 108 Pension Fund [Member]
Multiemployer Plans [Line Items]
Registration number					13-6366378
Pension Protection Act zone status					Green		Green
FIP/RP status					NA
Company contributions					$ 217		$ 269		337
Collective-bargaining agreement, expiration date					Feb. 28, 2022
Nurses and Local 813 IBT Retirement Plan [Member]
Multiemployer Plans [Line Items]
Registration number					13-3628926 - 001
Pension Protection Act zone status					Green		Green
FIP/RP status					NA
Company contributions					$ 58		$ 52		87
Collective-bargaining agreement, expiration date					Nov. 30, 2022
Other Multiemployer Plans [Member]
Multiemployer Plans [Line Items]
Company contributions					$ 75		$ 10		$ 0
Minimum [Member] | Western Conference of Teamsters Pension Trust [Member]
Multiemployer Plans [Line Items]
Collective-bargaining agreement, expiration date					Dec. 31, 2021
Minimum [Member] | International Union of Operating Engineers Pension Trust [Member]
Multiemployer Plans [Line Items]
Collective-bargaining agreement, expiration date					Mar. 31, 2021
Maximum [Member] | Western Conference of Teamsters Pension Trust [Member]
Multiemployer Plans [Line Items]
Collective-bargaining agreement, expiration date					Jun. 30, 2025
Maximum [Member] | International Union of Operating Engineers Pension Trust [Member]
Multiemployer Plans [Line Items]
Collective-bargaining agreement, expiration date					Mar. 31, 2024

Subsequent Events (Details)

Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Thousands	Feb. 16, 2022	Feb. 16, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Subsequent Event [Line Items]
Repurchase of common shares			3,003,822	1,271,977	0
Aggregate cost of common shares repurchase			$ 338,993	$ 105,654
Subsequent Event [Member]
Subsequent Event [Line Items]
Dividends, declared date	Feb. 16, 2022
Dividends per share amount	$ 0.23
Dividends, date to be paid	Mar. 16, 2022
Dividends, date of record	Mar. 2, 2022
Repurchase of common shares		3,388,155
Aggregate cost of common shares repurchase		$ 425,000

Valuation and Qualifying Acco_2

Valuation and Qualifying Accounts (Detail) - Allowance for Doubtful Accounts - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation allowances and reserves, balance	$ 19,380	$ 16,432	$ 16,760
Valuation allowances and reserves, charged to cost and expense	9,727	15,546	11,973
Valuation allowances and reserves, deductions	(10,627)	(12,598)	(12,301)
Valuation allowances and reserves, balance	$ 18,480	$ 19,380	$ 16,432