Waste Connections (WCN) 10-K 13 Feb 25 2024 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2024	Feb. 03, 2025	Jun. 30, 2024
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2024
Document Fiscal Year Focus	2024
Document Transition Report	false
Securities Act 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
Entity Address, Address Line Two	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
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 45,132,941,596
Entity Common Stock, Shares Outstanding		258,085,200
Auditor Firm ID	248
Auditor Name	GRANT THORNTON LLP
Auditor Location	Houston, Texas
Entity Central Index Key	0001318220
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	FY
Amendment Flag	false

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Current assets:
Cash and equivalents	$ 62,366	$ 78,399
Accounts receivable, net of allowance for credit losses of $25,730 and $23,553 at December 31, 2024 and 2023, respectively	935,027	856,953
Prepaid expenses and other current assets	229,519	206,433
Total current assets	1,226,912	1,141,785
Restricted cash	135,807	105,639
Restricted investments	78,126	70,350
Property and equipment, net	8,035,929	7,228,331
Operating lease right-of-use assets	308,198	261,782
Goodwill	7,950,406	7,404,400
Intangible assets, net	1,991,619	1,603,541
Other assets, net	90,812	100,048
Total assets	19,817,809	17,915,876
Current liabilities:
Accounts payable	637,371	642,455
Book overdraft	14,628	14,855
Deferred revenue	382,501	355,203
Accrued liabilities	736,824	521,428
Current portion of operating lease liabilities	40,490	32,533
Current portion of contingent consideration	59,169	94,996
Current portion of long-term debt and notes payable	7,851	26,462
Total current liabilities	1,878,834	1,687,932
Long-term portion of debt and notes payable	8,072,928	6,724,771
Long-term portion of operating lease liabilities	272,107	238,440
Long-term portion of contingent consideration	27,993	20,034
Deferred income taxes	958,340	1,022,480
Other long-term liabilities	747,253	524,438
Total liabilities	11,957,455	10,218,095
Commitments and contingencies (Note 13)
Equity:
Common shares: 258,067,487 shares issued and 258,019,389 shares outstanding at December 31, 2024; 257,659,921 shares issued and 257,600,479 shares outstanding at December 31, 2023	3,283,161	3,276,661
Additional paid-in capital	325,928	284,284
Accumulated other comprehensive loss	(205,740)	(9,826)
Treasury shares: 48,098 and 59,442 shares at December 31, 2024 and 2023, respectively	0	0
Retained earnings	4,457,005	4,141,690
Total Waste Connections' equity	7,860,354	7,692,809
Noncontrolling interest in subsidiaries		4,972
Total equity	7,860,354	7,697,781
Total liabilities and equity	$ 19,817,809	$ 17,915,876

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Statement Of Financial Position [Abstract]
Allowance for credit losses	$ 25,730	$ 23,553
Common shares, shares issued	258,067,487	257,659,921
Common shares, shares outstanding	258,019,389	257,600,479
Treasury shares	48,098	59,442

CONSOLIDATED STATEMENTS OF NET

CONSOLIDATED STATEMENTS OF NET INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income Statement [Abstract]
Revenues	$ 8,919,591	$ 8,021,951	$ 7,211,859
Operating expenses:
Cost of operations	5,191,706	4,744,513	4,336,012
Selling, general and administrative	883,445	799,119	696,467
Depreciation	974,001	845,638	763,285
Amortization of intangibles	189,768	157,573	155,675
Impairments and other operating items	613,012	238,796	18,230
Operating income	1,067,659	1,236,312	1,242,190
Interest expense	(326,804)	(274,642)	(202,331)
Interest income	11,607	9,350	5,950
Other income, net	10,471	12,481	3,154
Income before income tax provision	762,933	983,501	1,048,963
Income tax provision	(146,363)	(220,675)	(212,962)
Net income	616,570	762,826	836,001
Plus (less): Net loss (income) attributable to noncontrolling interests	1,003	(26)	(339)
Net income attributable to Waste Connections	$ 617,573	$ 762,800	$ 835,662
Earnings per common share attributable to Waste Connections' common shareholders:
Basic	$ 2.39	$ 2.96	$ 3.25
Diluted	$ 2.39	$ 2.95	$ 3.24
Shares used in the per share calculations:
Basic	257,965,871	257,551,129	257,383,578
Diluted	258,662,190	258,149,244	258,038,801
Cash dividends per common share	$ 1.17	$ 1.05	$ 0.945

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Net income	$ 616,570	$ 762,826	$ 836,001
Other comprehensive income (loss), before tax:
Foreign currency translation adjustment	(189,402)	53,633	(157,336)
Other comprehensive income (loss), before tax	(198,262)	44,614	(74,449)
Income tax expense (benefit) related to items of other comprehensive income (loss)	2,348	2,390	(21,965)
Other comprehensive income (loss), net of tax	(195,914)	47,004	(96,414)
Comprehensive income	420,656	809,830	739,587
Plus (less): Comprehensive loss (income) attributable to noncontrolling interests	1,003	(26)	(339)
Comprehensive income attributable to Waste Connections	421,659	809,804	739,248
Interest rate swap
Other comprehensive income (loss), before tax:
Interest rate swap amounts reclassified into interest expense	(20,467)	(19,607)	6,551
Changes in fair value of interest rate swaps	$ 11,607	$ 10,588	$ 76,336

CONSOLIDATED STATEMENTS OF EQUI

CONSOLIDATED STATEMENTS OF EQUITY - USD ($) $ in Thousands	COMMON SHARES Deferred compensation plan	COMMON SHARES Performance shares	COMMON SHARES Deferred share units	COMMON SHARES	ADDITIONAL PAID-IN CAPITAL	ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)	TREASURY SHARES	RETAINED EARNINGS	NONCONTROLLING INTERESTS	Total
Beginning Balances at Dec. 31, 2021				$ 3,693,027	$ 199,482	$ 39,584		$ 3,056,845	$ 4,607	$ 6,993,545
Beginning Balances, shares at Dec. 31, 2021				260,212,496
Beginning Balance, treasury shares at Dec. 31, 2021							70,662
Sale of common shares held in trust				$ 660						660
Sale of common shares held in trust, shares				5,203			(5,203)
Vesting of restricted share units (shares)	19,509	57,677		318,851
Tax withholdings related to net share settlements of equity-based compensation					(18,358)					(18,358)
Tax withholdings related to net share settlements of equity-based compensation, shares				(210,700)
Equity-based compensation					62,952					62,952
Exercise of warrants				104,253
Issuance of shares under employee share purchase plan				$ 3,270						$ 3,270
Issuance of shares under employee share purchase plan, shares				26,582						26,582
Repurchase of common shares (shares)				(3,388,155)						(3,388,155)
Repurchase of common shares				$ (424,999)						$ (424,999)
Cash dividends on common shares								(243,013)		(243,013)
Amounts reclassified into earnings, net of taxes						4,815				4,815
Changes in fair value of cash flow hedges, net of taxes						56,107				56,107
Foreign currency translation adjustment						(157,336)				(157,336)
Net income (loss)								835,662	339	836,001
Ending Balances at Dec. 31, 2022				$ 3,271,958	244,076	(56,830)		3,649,494	4,946	7,113,644
Ending Balances, shares at Dec. 31, 2022				257,145,716
Ending Balance, treasury shares at Dec. 31, 2022							65,459
Sale of common shares held in trust				$ 794						794
Sale of common shares held in trust, shares				6,017			(6,017)
Vesting of restricted share units (shares)	32,223	195,665		378,121
Tax withholdings related to net share settlements of equity-based compensation					(31,009)					(31,009)
Tax withholdings related to net share settlements of equity-based compensation, shares				(353,385)
Equity-based compensation					71,217					71,217
Exercise of warrants				166,314
Issuance of shares under employee share purchase plan				$ 3,909						$ 3,909
Issuance of shares under employee share purchase plan, shares				29,808						29,808
Repurchase of common shares (shares)										0
Cash dividends on common shares								(270,604)		$ (270,604)
Amounts reclassified into earnings, net of taxes						(14,411)				(14,411)
Changes in fair value of cash flow hedges, net of taxes						7,782				7,782
Foreign currency translation adjustment						53,633				53,633
Net income (loss)								762,800	26	762,826
Ending Balances at Dec. 31, 2023				$ 3,276,661	284,284	(9,826)		4,141,690	4,972	$ 7,697,781
Ending Balances, shares at Dec. 31, 2023				257,600,479						257,600,479
Ending Balance, treasury shares at Dec. 31, 2023							59,442			59,442
Sale of common shares held in trust				$ 2,014						$ 2,014
Sale of common shares held in trust, shares				11,344			(11,344)
Vesting of restricted share units (shares)	19,149	153,555	4,602	343,530
Tax withholdings related to net share settlements of equity-based compensation					(32,928)					(32,928)
Tax withholdings related to net share settlements of equity-based compensation, shares				(329,155)
Equity-based compensation					74,603					74,603
Exercise of warrants				186,629
Issuance of shares under employee share purchase plan				$ 4,486						$ 4,486
Issuance of shares under employee share purchase plan, shares				29,256						29,256
Repurchase of common shares (shares)										0
Cash dividends on common shares								(302,258)		$ (302,258)
Amounts reclassified into earnings, net of taxes						(15,043)				(15,043)
Changes in fair value of cash flow hedges, net of taxes						8,531				8,531
Foreign currency translation adjustment						(189,402)				(189,402)
Purchase of noncontrolling interests					(31)				(3,969)	(4,000)
Net income (loss)								617,573	$ (1,003)	616,570
Ending Balances at Dec. 31, 2024				$ 3,283,161	$ 325,928	$ (205,740)		$ 4,457,005		$ 7,860,354
Ending Balances, shares at Dec. 31, 2024				258,019,389						258,019,389
Ending Balance, treasury shares at Dec. 31, 2024							48,098			48,098

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 616,570	$ 762,826	$ 836,001
Adjustments to reconcile net income to net cash provided by operating activities:
Loss from disposal of assets, impairments and other	122,641	38,877	9,519
Adjustment to closure and post-closure liabilities	480,786	159,547	0
Depreciation	974,001	845,638	763,285
Amortization of intangibles	189,768	157,573	155,675
Deferred income taxes, net of acquisitions	(57,285)	6,329	93,481
Current period provision for expected credit losses	20,243	17,430	17,353
Amortization of debt issuance costs	10,007	6,483	5,454
Share-based compensation	77,885	70,436	63,485
Interest accretion	36,001	22,720	17,668
Payment of contingent consideration recorded in earnings	(35,035)		(2,982)
Adjustments to contingent consideration	(3)	30,367	(1,030)
Other	2,656	(3,943)	(8,217)
Changes in operating assets and liabilities, net of effects from acquisitions:
Accounts receivable, net	(10,646)	(20,630)	(100,546)
Prepaid expenses and other current assets	(14,360)	10,262	(752)
Accounts payable	(33,323)	32,327	192,850
Deferred revenue	18,235	26,519	42,252
Accrued liabilities	90,035	21,753	(28,082)
Capping, closure and post-closure expenditures	(247,936)	(39,427)	(18,881)
Other long-term liabilities	(11,313)	(18,270)	(14,041)
Net cash provided by operating activities	2,228,927	2,126,817	2,022,492
CASH FLOWS FROM INVESTING ACTIVITIES:
Cash paid for current year acquisitions	(2,120,878)	(676,793)	(2,206,901)
Capital expenditures for property and equipment	(1,055,988)	(934,000)	(912,677)
Proceeds from disposal of assets	7,903	31,581	30,676
Proceeds from sale of investment in noncontrolling interests	37,000	0	0
Other	(27,213)	(1,867)	1,731
Net cash used in investing activities	(3,159,176)	(1,581,079)	(3,087,171)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from long-term debt	4,564,469	1,818,765	4,816,146
Principal payments on notes payable and long-term debt	(3,245,419)	(2,052,153)	(3,073,985)
Payment of contingent consideration recorded at acquisition date	(27,743)	(13,317)	(16,911)
Change in book overdraft	(227)	(790)	(1,076)
Payments for repurchase of common shares	0		(424,999)
Payments for cash dividends	(302,258)	(270,604)	(243,013)
Tax withholdings related to net share settlements of equity-based compensation	(32,928)	(31,009)	(18,358)
Debt issuance costs	(13,449)		(13,271)
Proceeds from issuance of shares under employee share purchase plan	4,486	3,909	3,270
Proceeds from sale of common shares held in trust	2,014	794	660
Other	(4,000)
Net cash provided by (used in) financing activities	944,945	(544,405)	1,028,463
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(561)	1,341	(2,035)
Net increase in cash, cash equivalents and restricted cash	14,135	2,674	(38,251)
Cash, cash equivalents and restricted cash at beginning of year	184,038	181,364	219,615
Cash, cash equivalents and restricted cash at end of year	198,173	184,038	181,364
SUPPLEMENTARY DISCLOSURES OF CASH FLOW INFORMATION AND NON-CASH TRANSACTIONS:
Cash paid for income taxes	215,997	207,020	100,156
Cash paid for interest	298,934	260,923	177,424
Changes in accrued capital expenditures for property and equipment	21,108	(41,505)	36,671
In connection with its acquisitions, the Company assumed liabilities as follows:
Fair value of assets acquired	2,352,337	813,136	2,471,202
Cash paid for current year acquisitions	(2,120,878)	(676,793)	(2,206,901)
Liabilities assumed and notes payable issued to sellers of businesses acquired	$ 231,459	$ 136,343	$ 264,301

Business

Business	12 Months Ended
	Dec. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [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, including by rail, along with resource recovery primarily through recycling and renewable

New Accounting Standards and Re

New Accounting Standards and Reclassifications	12 Months Ended
	Dec. 31, 2024
New Accounting Standards and Reclassifications [Abstract]
New Accounting Standards and Reclassifications	2. NEW ACCOUNTING STANDARDS AND RECLASSIFICATIONS Accounting Standards Adopted Disclosure of Significant Segment Expenses and Other Segment Items The Company adopted the amended guidance for its fiscal year 2024 annual financial statements and interim financial statements thereafter and have applied this standard retroactively for all prior periods presented in the financial statements. Accounting Standards Pending Adoption Additional Income Tax Disclosures Disaggregation of Income Statement Expenses standard retrospectively. Early adoption is permitted. The Company does not expect the adoption of this guidance to have a material impact on its consolidated financial statements.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2024
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. All references to “dollars” or “$” used herein refer to U.S. dollars, and all references to “CAD $” used herein refer to Canadian dollars, unless otherwise stated. Cash Equivalents The Company considers all highly liquid investments with original maturities of three months or less at purchase to be cash equivalents. As of December 31, 2024 and 2023, 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, ​ 2024 2023 2022 Commercial $ 2,670,549 ​ $ 2,476,891 $ 2,176,295 Residential ​ 2,258,911 ​ ​ 2,125,068 ​ ​ 1,891,108 Industrial and construction roll off ​ 1,403,313 ​ ​ 1,333,020 ​ ​ 1,183,624 Total collection ​ 6,332,773 ​ ​ 5,934,979 ​ ​ 5,251,027 Landfill ​ 1,557,872 ​ ​ 1,483,397 ​ ​ 1,328,942 Transfer ​ 1,349,080 ​ ​ 1,198,385 ​ ​ 1,026,050 Recycling ​ 241,873 ​ ​ 147,039 ​ ​ 204,876 E&P ​ 521,504 ​ ​ 232,211 ​ ​ 210,562 Intermodal and other ​ 191,887 ​ ​ 171,721 ​ ​ 188,471 Intercompany ​ (1,275,398) ​ ​ (1,145,781) ​ ​ (998,069) Total $ 8,919,591 ​ $ 8,021,951 $ 7,211,859 ​ 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, 2024 was recognized as revenue during the three months ended December 31, 2024 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, the method of transportation used 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, such as solid waste collection service contracts, are satisfied over time, and revenue is recognized based on the value provided to the customer during the period. In many of the Company’s markets, solid waste collection service contracts exist as exclusive franchise agreements or municipal contracts. 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. Such contracts are generally within the Company’s collection, recycling and other lines of business and have a weighted average remaining contract life of approximately five years, excluding certain exclusive and perpetual agreements, such as governmental certificates . 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, ​ ​ 2024 2023 Beginning balance ​ $ 23,553 ​ $ 22,939 Current period provision for expected credit losses ​ ​ 20,243 ​ ​ 17,430 Write-offs charged against the allowance ​ ​ (23,141) ​ ​ (22,743) Recoveries collected ​ ​ 5,255 ​ ​ 5,853 Impact of changes in foreign currency ​ ​ (180) ​ ​ 74 Ending balance ​ $ 25,730 ​ $ 23,553 ​ 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 Sheets, and are amortized to Selling, general and administrative expense over the estimated life of the relevant customer relationship, which ranges from one Company would have recognized is one year or less. The Company had $28,161 and $25,977 of deferred sales incentives at December 31, 2024 and 2023, respectively. During the years ended December 31, 2024, 2023 and 2022, the Company recorded a total of $25,047, $25,855 and $22,675, 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 5 – 12 years ​ 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 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 layers for final capping, closure and post-closure liabilities is based on its long-term credit adjusted risk-free rate. The Company’s discount rate assumption for purposes of computing 2024 and 2023 “layers” for final capping, closure and post-closure obligations was 5.50% for each of 2024 and 2023. The Company’s long-term inflation rate assumption was 2.75% for each of the years ended December 31, 2024 and 2023. 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. In the event that changes in an estimate for a closure and post-closure liability are associated with a significant change in facts and circumstances at a landfill or a non-operating section of a landfill, corresponding adjustments to recorded liabilities and Impairments and other operating items are made as soon as is practical. 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 one The following is a reconciliation of the Company’s final capping, closure and post-closure liability balance from December 31, 2022 to December 31, 2024: ​ ​ ​ ​ ​ Final capping, closure and post-closure liability at December 31, 2022 $ 344,606 Liability adjustments ​ 189,136 Accretion expense associated with landfill obligations ​ 19,418 Closure payments ​ (39,429) Assumption of closure liabilities from acquisitions ​ 7,687 Foreign currency translation adjustment ​ ​ 815 Final capping, closure and post-closure liability at December 31, 2023 ​ 522,233 Liability adjustments ​ 497,955 Accretion expense associated with landfill obligations ​ 29,373 Closure payments ​ (247,552) Assumption of closure liabilities from acquisitions ​ ​ 60,913 Foreign currency translation adjustment ​ (2,799) Final capping, closure and post-closure liability at December 31, 2024 ​ $ 860,123 ​ Liability adjustments of $497,955 and $189,136 for the years ended December 31, 2024 and 2023, 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. In the event that changes in an estimate for a closure and post-closure liability are associated with a significant change in facts and circumstances at a landfill or a non-operating section of a landfill, corresponding adjustments to recorded liabilities and Impairments and other operating items are made as soon as is practical. In 2023, the Company recorded an additional $159,547 of charges to adjust the carrying value of a closure and post-closure liability at an area of a landfill site that has been deemed to reach final capacity. Furthermore, during the quarter ended December 31, 2024, the Company recorded an additional $480,786 of charges to adjust the carrying value of the closure and post-closure liability at the same landfill, which ceased active waste disposal operations as of December 31, 2024. See “Final capping, closure and post-closure obligations” within this Note 3 for additional information regarding the Company’s accounting for landfills. - 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 4 to 51 years). The Company uses an accelerated or straight line basis for amortization, depending on the attributes of the related intangibles. 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. 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. The Company’s reporting units consisted of its six geographic solid waste operating segments at December 31, 2024, 2023 and 2022. 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 six geographic operating segments at December 31, 2024, 2023 and 2022 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 2024 discounted cash flow analyses were based on ten-year financial forecasts, which in turn were based on the 2025 annual budget developed internally by management. These forecasts reflect operating profit margins that were consistent with 2024 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 8.5%. 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 six geographic operating segments as a result of its annual goodwill and indefinite-lived intangible impairment tests for the years ended December 31, 2024, 2023 or 2022. 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 quarter ended December 31, 2024, the Company made the decision to cease active waste disposal operations as of December 31, 2024 at the Chiquita Canyon Landfill, and therefore recorded a charge of $116,090 to Impairments and other operating items in the Consolidated Statement of Net Income, which reduced the carrying value of property and equipment. During the years ended December 31, 2023 and 2022, the Company did not record any significant impairment charges for finite-lived intangible assets or property and equipment. 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 consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2024 ​ December 31, 2023 ​ ​ Restricted ​ Restricted ​ Restricted ​ Restricted ​ Cash Investments Cash Investments Settlement of insurance claims ​ $ 121,751 ​ $ — ​ $ 83,270 ​ $ — Landfill closure and post-closure obligations ​ ​ 8,852 ​ ​ 77,855 ​ ​ 13,546 ​ ​ 68,266 Other financial assurance requirements ​ ​ 5,204 ​ ​ 271 ​ ​ 8,823 ​ ​ 2,084 ​ ​ $ 135,807 ​ $ 78,126 ​ $ 105,639 ​ $ 70,350 ​ See Note 12 for further information on restricted cash and restricted investments. 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, 2024 and 2023, 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, 2024 and 2023, based on current borrowing rates, current

Use of Estimates and Assumption

Use of Estimates and Assumptions	12 Months Ended
	Dec. 31, 2024
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. 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, 2024
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, ​ 2024 2023 Income taxes receivable $ 37,599 $ 28,124 Parts and supplies ​ ​ 71,156 ​ ​ 61,673 Prepaid insurance ​ ​ 40,014 ​ ​ 26,607 Unrealized cash flow hedge gains ​ ​ 10,545 ​ ​ 15,842 Prepaid licenses and permits ​ ​ 14,141 ​ ​ 13,898 Other ​ ​ 56,064 ​ ​ 60,289 ​ $ 229,519 $ 206,433 ​

PROPERTY AND EQUIPMENT, NET

PROPERTY AND EQUIPMENT, NET	12 Months Ended
	Dec. 31, 2024
PROPERTY AND EQUIPMENT, NET
PROPERTY AND EQUIPMENT, NET	6. PROPERTY AND EQUIPMENT, NET Property and equipment, net consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2024 2023 Landfill site costs ​ $ 5,778,483 ​ $ 5,507,596 Rolling stock ​ 3,428,765 ​ 3,084,623 Land, buildings and improvements ​ 2,328,287 ​ 1,807,719 Containers ​ 1,364,624 ​ 1,277,594 Machinery and equipment ​ 1,539,394 ​ 1,222,792 Construction in progress ​ 191,404 ​ 167,025 ​ ​ 14,630,957 ​ 13,067,349 Less accumulated depreciation and depletion ​ (6,595,028) ​ (5,839,018) ​ ​ $ 8,035,929 ​ $ 7,228,331 ​ Machinery and equipment included $8,956 and $9,762, at December 31, 2024 and 2023, 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, 2024, 2023 and 2022, was $289,696, $254,633 and $232,251, respectively.

LEASES

LEASES	12 Months Ended
	Dec. 31, 2024
LEASES.
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, 2024, 2023 and 2022. 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, 2024, 2023 and 2022. 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. Lease cost for operating and finance leases for the years ended December 31, 2024, 2023 and 2022 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2024 ​ 2023 ​ 2022 Operating lease cost $ 53,329 ​ $ 47,840 ​ $ 41,891 Finance lease cost: ​ ​ ​ ​ ​ ​ ​ ​ Amortization of leased assets ​ 3,375 ​ ​ 2,852 ​ ​ 2,484 Interest on leased liabilities ​ 273 ​ ​ 228 ​ ​ 219 Total lease cost $ 56,977 ​ $ 50,920 ​ $ 44,594 ​ Supplemental cash flow information and non-cash activity related to the Company’s leases are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2024 ​ ​ 2023 ​ ​ 2022 Cash paid for amounts included in the measurement of lease liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating cash flows from operating leases ​ $ 50,837 ​ $ 46,688 ​ $ 40,782 Operating cash flows from finance leases ​ $ 273 ​ $ 228 ​ $ 219 Financing cash flows from finance leases ​ $ 3,356 ​ $ 2,817 ​ $ 2,427 Non-cash activity: ​ ​ ​ ​ ​ ​ ​ ​ ​ Right-of-use assets obtained in exchange for lease liabilities - operating leases ​ $ 62,922 ​ $ 92,503 ​ $ 63,648 Right-of-use assets obtained in exchange for lease liabilities - finance leases ​ $ 2,569 ​ $ 1,388 ​ $ 3,369 ​ Weighted-average remaining lease term and discount rate for the Company’s leases are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2024 ​ 2023 ​ 2022 Weighted average remaining lease term - operating leases ​ 9.7 years 10.9 years 8.9 years Weighted average remaining lease term - finance leases ​ 2.8 years ​ 3.4 years ​ 4.2 years Weighted average discount rate - operating leases ​ 4.34 % 4.04 % 2.93 % Weighted average discount rate - finance leases ​ 2.99 % ​ 2.36 % ​ 1.96 % ​ As of December 31, 2024, future minimum lease payments, reconciled to the respective lease liabilities, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating Leases ​ ​ Finance Leases 2025 $ 53,080 ​ $ 3,870 2026 ​ 50,343 ​ 3,284 2027 ​ 46,834 ​ 1,858 2028 ​ 39,682 ​ 540 2029 ​ 32,950 ​ 126 Thereafter ​ 170,462 ​ — Minimum lease payments ​ 393,351 ​ 9,678 Less: imputed interest ​ (80,754) ​ ​ (431) Present value of minimum lease payments ​ ​ 312,597 ​ ​ 9,247 Less: current portion of lease liabilities ​ ​ (40,490) ​ ​ (3,631) Long-term portion of lease liabilities ​ $ 272,107 ​ $ 5,616 ​ See Note 11 for further information regarding finance leases.

ACQUISITIONS

ACQUISITIONS	12 Months Ended
	Dec. 31, 2024
ACQUISITIONS
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 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 20 immaterial non-hazardous solid waste collection, transfer, recycling and disposal businesses and four immaterial E&P waste treatment and disposal businesses during the year ended December 31, 2024. The total transaction-related expenses incurred during the year ended December 31, 2024 for these acquisitions were $26,059. These expenses are included in Selling, general and administrative expenses in the Company’s Consolidated Statements of Net Income. The Company acquired 12 immaterial non-hazardous solid waste collection, transfer, recycling and disposal businesses and one immaterial E&P disposal business during the year ended December 31, 2023. The total transaction-related expenses incurred during the year ended December 31, 2023 for these acquisitions were $10,653. These expenses are included in Selling, general and administrative expenses in the Company’s Consolidated Statements of Net Income. The Company acquired 24 immaterial non-hazardous solid waste collection, transfer, recycling and disposal businesses during the year ended December 31, 2022. The total transaction-related expenses incurred during the year ended December 31, 2022 for these acquisitions were $24,933. These expenses are included in Selling, general and administrative expenses in the Company’s Consolidated Statements of Net Income. 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, 2024, 2023 and 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2024 2023 2022 ​ ​ Acquisitions ​ Acquisitions ​ Acquisitions Fair value of consideration transferred: ​ ​ ​ Cash ​ $ 2,120,878 ​ $ 676,793 ​ $ 2,206,901 Debt assumed ​ 77,766 ​ 76,001 ​ 127,136 ​ ​ 2,198,644 ​ 752,794 ​ 2,334,037 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired: ​ ​ ​ ​ ​ Accounts receivable ​ 100,995 ​ ​ 18,006 ​ 49,696 Prepaid expenses and other current assets ​ 13,513 ​ ​ 5,025 ​ 9,428 Restricted investments ​ ​ — ​ ​ 5,462 ​ ​ 7,469 Operating lease right-of-use assets ​ ​ 24,700 ​ ​ 15,364 ​ ​ 4,707 Property and equipment ​ 913,729 ​ ​ 207,164 ​ 1,073,155 Long-term franchise agreements and contracts ​ 159,028 ​ ​ 76,401 ​ 239,866 Customer lists ​ 214,459 ​ ​ 19,719 ​ 74,940 Permits and other intangibles ​ ​ 224,728 ​ ​ 3,050 ​ ​ 187,107 Other assets ​ 1,671 ​ ​ 24 ​ 243 Accounts payable and accrued liabilities ​ (27,902) ​ ​ (14,596) ​ (56,633) Current portion of operating lease liabilities ​ ​ (2,875) ​ ​ (712) ​ ​ (1,546) Deferred revenue ​ (12,148) ​ ​ (3,443) ​ (10,761) Contingent consideration ​ (28,885) ​ ​ (13,450) ​ (6,642) Long-term portion of operating lease liabilities ​ ​ (14,774) ​ ​ (14,652) ​ ​ (3,161) Other long-term liabilities ​ (67,109) ​ ​ (10,277) ​ (6,915) Deferred income taxes ​ — ​ ​ (3,212) ​ (51,507) Total identifiable net assets ​ 1,499,130 ​ 289,873 ​ 1,509,446 Goodwill ​ $ 699,514 ​ $ 462,921 ​ $ 824,591 ​ Goodwill acquired in 2024, 2023 and 2022 totaling $699,514, $372,671 and $510,755, respectively, is expected to be deductible for tax purposes. The fair value of acquired working capital related to seven immaterial acquisitions completed during the year ended December 31, 2024, 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 seven acquisitions are not expected to be material to the Company’s financial position. The adjustments recorded during the year ended December 31, 2024 relating to finalizing the acquired working capital for the immaterial acquisitions completed during the year ended December 31, 2023 were not material to the Company’s financial position. The gross amount of trade receivables due under contracts acquired during the year ended December 31, 2024, was $106,259, of which $5,264 was expected to be uncollectible. The gross amount of trade receivables due under contracts acquired during the year ended December 31, 2023, was $19,202, of which $1,196 was expected to be uncollectible. The gross amount of trade receivables due under contracts acquired during the year ended December 31, 2022, was $54,332, of which $4,636 was expected to be uncollectible. The Company did not acquire any other class of receivable as a result of the acquisition of these businesses.

INTANGIBLE ASSETS, NET

INTANGIBLE ASSETS, NET	12 Months Ended
	Dec. 31, 2024
INTANGIBLE ASSETS, NET
INTANGIBLE ASSETS, NET	9. INTANGIBLE ASSETS, NET Intangible assets, exclusive of goodwill, consisted of the following at December 31, 2024: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ ​ Accumulated Net ​ ​ Carrying ​ Accumulated ​ Impairment ​ Carrying ​ ​ Amount ​ Amortization ​ Loss ​ Amount Finite-lived intangible assets: ​ ​ ​ ​ Long-term franchise agreements and contracts ​ $ 1,104,585 ​ $ (400,674) ​ $ — ​ $ 703,911 Customer lists ​ 1,005,355 ​ (693,594) ​ — ​ 311,761 Permits and other ​ 999,357 ​ (164,239) ​ (40,784) ​ 794,334 ​ ​ 3,109,297 ​ (1,258,507) ​ (40,784) ​ 1,810,006 Indefinite-lived intangible assets: ​ ​ ​ ​ Solid waste collection and transportation permits ​ 181,613 ​ — ​ — ​ 181,613 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Intangible assets, exclusive of goodwill ​ $ 3,290,910 ​ $ (1,258,507) ​ $ (40,784) ​ $ 1,991,619 ​ The weighted-average amortization period of long-term franchise agreements and contracts acquired during the year ended December 31, 2024 was 14.8 years. The weighted-average amortization period of customer lists acquired during the year ended December 31, 2024 was 10.1 years. The weighted-average amortization period of finite-lived permits and other acquired during the year ended December 31, 2024 was 37.8 years. ​ Intangible assets, exclusive of goodwill, consisted of the following at December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ ​ Accumulated Net ​ ​ Carrying ​ Accumulated ​ Impairment ​ Carrying ​ ​ Amount ​ Amortization ​ Loss ​ Amount Finite-lived intangible assets: ​ ​ ​ ​ Long-term franchise agreements and contracts ​ $ 960,033 ​ $ (343,099) ​ $ — ​ $ 616,934 Customer lists ​ 806,257 ​ (606,192) ​ — ​ 200,065 Permits and other ​ 784,905 ​ (139,192) ​ (40,784) ​ 604,929 ​ ​ 2,551,195 ​ (1,088,483) ​ (40,784) ​ 1,421,928 Indefinite-lived intangible assets: ​ ​ ​ ​ Solid waste collection and transportation permits ​ 181,613 ​ — ​ — ​ 181,613 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Intangible assets, exclusive of goodwill ​ $ 2,732,808 ​ $ (1,088,483) ​ $ (40,784) ​ $ 1,603,541 ​ Estimated future amortization expense for the next five years relating to finite-lived intangible assets owned as of December 31, 2024 is as follows: ​ ​ ​ ​ ​ For the year ending December 31, 2025 $ 180,792 For the year ending December 31, 2026 ​ $ 157,827 For the year ending December 31, 2027 ​ $ 137,790 For the year ending December 31, 2028 ​ $ 122,230 For the year ending December 31, 2029 ​ $ 110,584 ​

ACCRUED LIABILITIES

ACCRUED LIABILITIES	12 Months Ended
	Dec. 31, 2024
ACCRUED LIABILITIES
ACCRUED LIABILITIES	10. ACCRUED LIABILITIES Accrued liabilities consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2024 2023 Insurance claims and premiums ​ $ 244,536 ​ $ 184,403 Final capping, closure and post-closure liability ​ ​ 199,736 ​ ​ 92,946 Payroll and payroll-related ​ 127,518 ​ 108,423 Interest payable ​ 68,455 ​ 52,726 Property taxes ​ ​ 17,548 ​ ​ 15,545 Environmental remediation reserves ​ 8,808 ​ 10,860 Cell processing reserves ​ 2,148 ​ 3,246 Transaction-related expenses ​ ​ 1,471 ​ ​ 958 Other ​ 66,604 ​ 52,321 ​ ​ $ 736,824 ​ $ 521,428 ​

Long-Term Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2024
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, 2024 and 2023: ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2024 2023 Revolving Credit Agreement, bearing interest ranging from 4.59% to 7.50% (a) $ 2,164,325 ​ $ — Revolver under 2021 Revolving and Term Credit Agreement, bearing interest ranging from 6.40% to 8.50% (b) ​ — ​ ​ 453,245 Term loan under 2021 Revolving and Term Credit Agreement, bearing interest at 6.50% (b) — ​ ​ 650,000 Term loan under 2022 Term Loan Agreement, bearing interest at 6.44% (b), (c) ​ — ​ ​ 800,000 4.25% Senior Notes due 2028 ​ 500,000 ​ ​ 500,000 3.50% Senior Notes due 2029 ​ 500,000 ​ ​ 500,000 4.50% Senior Notes due 2029 ​ 347,500 ​ ​ — 2.60% Senior Notes due 2030 ​ 600,000 ​ ​ 600,000 2.20% Senior Notes due 2032 ​ 650,000 ​ ​ 650,000 3.20% Senior Notes due 2032 ​ 500,000 ​ ​ 500,000 4.20% Senior Notes due 2033 ​ 750,000 ​ ​ 750,000 5.00% Senior Notes due 2034 ​ 750,000 ​ ​ — 3.05% Senior Notes due 2050 ​ 500,000 ​ ​ 500,000 2.95% Senior Notes due 2052 ​ 850,000 ​ ​ 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 2044 (a) 30,641 ​ ​ 48,774 Finance leases, bearing interest ranging from 1.89% to 5.07%, with lease expiration dates ranging from 2026 to 2029 (a) ​ 9,247 ​ ​ 10,034 ​ 8,151,713 ​ 6,812,053 Less – current portion (7,851) ​ ​ (26,462) Less – unamortized debt discount and issuance costs (70,934) ​ ​ (60,820) Long-term portion of debt and notes payable $ 8,072,928 ​ $ 6,724,771 (a) Interest rates represent the interest rates incurred at December 31, 2024. (b) Interest rates represent the interest rates incurred at December 31, 2023. (c) Interest rate margin for term loan under 2022 Term Loan Agreement was 1.00% at December 31, 2023. Revolving Credit Agreement The Company, as borrower, 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, and the other lenders and financial institutions from time to time party thereto (the “Lenders”) are party to that certain Revolving Credit Agreement, dated as of February 27, 2024 (as amended, restated, supplemented or otherwise modified from time to time, the “Revolving Credit Agreement”), pursuant to which the Lenders provide loans and other credit extensions to the Company under a revolving credit facility. Borrowings under the Revolving Credit Agreement are unsecured and there are no subsidiary guarantors under the Revolving Credit Agreement. ​ The Revolving Credit Agreement (i) has a scheduled maturity date of February 27, 2029 (subject to certain extension mechanics therein by which the Company may request two additional one-year maturity date extensions), (ii) provides for revolving advances up to an aggregate principal amount of $3,000,000 at any one time outstanding (subject to satisfaction of certain conditions at the time advances are made) and (iii) provides for, at the Company’s discretion, flexibility for an uncommitted upsize of the aggregate principal amount by up to $1,000,000 (to an aggregate principal amount of up to $4,000,000). As of December 31, 2024, there are no commitments by lenders for any such increases in aggregate principal amount of revolving advances described in the preceding sentence. The Revolving Credit Agreement provides for letters of credit in an aggregate amount not to exceed $320,000 and swing line loans in an aggregate amount not to exceed $100,000, in each case, to be issued at the request of the Company subject to the terms therein and with such sublimits included in the aggregate commitments of the credit facility. The Company has $4,401 of debt issuance costs related to the revolver under the Revolving Credit Agreement recorded in Other assets, net in the Consolidated Balance Sheets at December 31, 2024, which are being amortized through the maturity date, or February 27, 2029. Advances are available under the Revolving Credit Agreement in U.S. dollars and Canadian dollars. Interest accrues on revolving advances, at the Company’s option, (i) at a term rate based on the Secured Overnight Financing Rate as administered by the Federal Reserve Bank of New York (or a successor administrator thereof) (“term SOFR”) or a base rate for U.S. dollar borrowings, plus an applicable margin, and (ii) at a term rate based on the Canadian Overnight Repo Rate Average as administered and published by the Bank of Canada (or a successor administrator thereof) (“term CORRA”) or at the Canadian prime rate for Canadian dollar borrowings, plus an applicable margin. Interest for term SOFR loans has a credit spread adjustment of 0.10% for all applicable interest periods and interest for term CORRA loans has a credit spread adjustment of 0.29547% for an interest period of one month’s duration and 0.32138% for an interest period of three months’ duration. Fees for letters of credit in U.S. 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 term SOFR loans, term CORRA loans and 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 commitment 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 Revolving 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 Revolving Credit Agreement to be due and payable. The Revolving 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 Revolving Credit Agreement) as of such date to (b) Consolidated EBITDA (as defined in the Revolving 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, 2024, the Company was in compliance with all applicable covenants in the Revolving Credit Agreement. ​ Details of the Revolving Credit Agreement at December 31, 2024 and details of the 2021 Revolving and Term Credit Agreement (as defined below) at December 31, 2023 are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2024 2023 Revolver ​ ​ ​ Available $ 778,374 ​ $ 1,357,013 ​ Letters of credit outstanding $ 57,301 ​ $ 39,742 ​ Total amount drawn, as follows: $ 2,164,325 ​ $ 453,245 ​ Amount drawn – U.S. Term SOFR rate loan $ 800,000 ​ $ 90,000 ​ Interest rate applicable – U.S. Term SOFR rate loan ​ 5.65 % ​ 6.46 % Interest rate margin – U.S. Term SOFR rate loan ​ 1.00 % ​ 1.00 % Amount drawn – U.S. Term SOFR rate loan $ 500,000 ​ $ 150,000 ​ Interest rate applicable – U.S. Term SOFR rate loan ​ 5.69 % ​ 6.50 % Interest rate margin – U.S. Term SOFR rate loan ​ 1.00 % ​ 1.00 % Amount drawn – U.S. Term SOFR rate loan $ 50,000 ​ $ — ​ Interest rate applicable – U.S. Term SOFR rate loan ​ 5.46 % ​ — % Interest rate margin – U.S. Term SOFR rate loan ​ 1.00 % ​ — % Amount drawn – U.S. base rate loan $ 95,000 ​ $ 28,000 ​ Interest rate applicable – U.S. base rate loan ​ 7.50 % ​ 8.50 % Interest rate margin – U.S. base rate loan ​ — % ​ — % Amount drawn – Canadian Term CORRA loan $ 590,750 ​ $ — ​ Interest rate applicable - Canadian term CORRA loan ​ 5.24 % ​ — % Interest rate margin – Canadian term CORRA loan ​ 1.00 % ​ — % Amount drawn – Canadian Term CORRA loan $ 86,875 ​ $ — ​ Interest rate applicable - Canadian term CORRA loan ​ 4.59 % ​ — % Interest rate margin – Canadian term CORRA loan ​ 1.00 % ​ — % Amount drawn – Canadian prime rate loan $ 41,700 ​ $ 15,122 ​ Interest rate applicable - Canadian prime rate loan 5.45 % 7.20 % Interest rate margin – Canadian prime rate loan — % — % Amount drawn – Canadian bankers’ acceptance $ — ​ $ 153,111 ​ Interest rate applicable – Canadian bankers’ acceptance — % 6.46 % Interest rate acceptance fee – Canadian bankers’ acceptance — % 1.00 % Amount drawn – Canadian bankers’ acceptance $ — ​ $ 17,012 ​ Interest rate applicable – Canadian bankers’ acceptance ​ — % ​ 6.40 % Interest rate acceptance fee – Canadian bankers’ acceptance ​ — % ​ 1.00 % Commitment – rate applicable 0.09 % 0.09 % Term loan ​ ​ ​ ​ Amount drawn – U.S. Term SOFR rate loan $ — ​ $ 650,000 ​ Interest rate applicable – U.S. Term SOFR rate loan ​ — % ​ 6.50 % Interest rate margin – U.S. Term SOFR rate loan ​ — % ​ 1.00 % ​ In addition to the $57,301 of letters of credit at December 31, 2024 issued and outstanding under the Revolving Credit Agreement, the Company has issued and outstanding letters of credit totaling $113,385 under facilities other than the Revolving Credit Agreement. 2021 Revolving Credit and Term Loan Agreement On February 27, 2024, the Company used a portion of the proceeds from borrowings under the Revolving Credit Agreement to (i) prepay the amounts outstanding under that certain Second Amended and Restated Revolving Credit and Term Loan Agreement, dated as of July 30, 2021 (as amended, restated, supplemented or otherwise modified from time to time, the “2021 Revolving and Term Credit Agreement”), among the Company, as borrower, 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, and the lenders and any other financial institutions from time to time party thereto and (ii) terminate the 2021 Revolving and Term Credit Agreement and the loan documents associated therewith. 2022 Term Loan Agreement On February 27, 2024, the Company used a portion of the proceeds from borrowings under the Revolving Credit Agreement to (i) prepay the amounts outstanding under that certain Term Loan Agreement, dated as of October 31, 2022 (as amended, restated, supplemented or otherwise modified from time to time, the “2022 Term Loan Agreement”), among the Company, as borrower, Bank of America, N.A., as administrative agent, and the lenders and any other financial institutions from time to time party thereto and (ii) terminate the 2022 Term Loan Agreement and the loan documents associated therewith. Senior Notes On November 16, 2018, the Company completed an underwritten public offering of $500,000 aggregate principal amount of 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 $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 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 $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”). 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. On March 9, 2022, the Company completed an underwritten public offering of $500,000 aggregate principal amount of 3.20% Senior Notes due June 1, 2032 (the “New 2032 Senior Notes”). The New 2032 Senior Notes were issued under the Indenture, as supplemented through the Sixth Supplemental Indenture, dated as of March 9, 2022. The Company is amortizing a $375 debt discount and $4,668 of debt issuance costs through the maturity date of the New 2032 Senior Notes. The Company may redeem some or all of the New 2032 Senior Notes at its option prior to March 1, 2032 (three months before the maturity date) (the “New 2032 Senior Notes Par Call 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 New 2032 Senior Notes redeemed, or the sum of the present values of the remaining scheduled payments of principal and interest on the New 2032 Senior Notes redeemed discounted to the redemption date (assuming the New 2032 Senior Notes matured on the New 2032 Senior Notes Par Call Date), plus, in either case, accrued and unpaid interest thereon to the redemption date. Commencing on March 1, 2032 (three months before the maturity date), the Company may redeem some or all of the New 2032 Senior Notes, at any time and from time to time, at a redemption price equal to the principal amount of the New 2032 Senior Notes being redeemed plus accrued and unpaid interest thereon to the redemption date. On August 18, 2022, the Company completed an underwritten public offering of $750,000 aggregate principal amount of 4.20% Senior Notes due January 15, 2033 (the “2033 Senior Notes”). The 2033 Senior Notes were issued under the Indenture, as supplemented through the Seventh Supplemental Indenture, dated as of August 18, 2022. The Company is amortizing a $2,040 debt discount and $6,878 of debt issuance costs through the maturity date of the 2033 Senior Notes. The Company may redeem some or all of the 2033 Senior Notes at its option prior to October 15, 2032 (three months before the maturity date) (the “2033 Senior Notes Par Call 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 2033 Senior Notes redeemed, or the sum of the present values of the remaining scheduled payments of principal and interest on the 2033 Senior Notes redeemed discounted to the redemption date (assuming the 2033 Senior Notes matured on the 2033 Senior Notes Par Call Date), plus, in either case, accrued and unpaid interest thereon to the redemption date. Commencing on October 15, 2032 (three months before the maturity date), the Company may redeem some or all of the 2033 Senior Notes, at any time and from time to time, at a redemption price equal to the principal amount of the 2033 Senior Notes being redeemed plus accrued and unpaid interest thereon to the redemption date. On February 21, 2024, the Company completed an underwritten public offering of $750,000 aggregate principal amount of 5.00% Senior Notes due March 1, 2034 (the “2034 Senior Notes”). The 2034 Senior Notes were issued under an Indenture, as supplemented by the Eighth Supplemental Indenture, dated as of February 21, 2024. The Company is amortizing a $8,738 debt discount and $6,978 of debt issuance costs through the maturity date of the 2034 Senior Notes. The Company may, prior to December 1, 2033 (three months before the maturity date) (the “2034 Senior Notes Par Call Date”), redeem some or all of the 2034 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 2034 Senior Notes redeemed, or the sum of the present values of the remaining scheduled payments of principal and interest on the 2034 Senior Notes redeemed discounted to the redemption date (assuming the 2034 Senior Notes matured on the 2034 Senior Notes Par Call Date), plus, in either case, accrued and unpaid interest thereon to the redemption date. Commencing on December 1, 2033 (three months before the maturity date), the Company may redeem some or all of the 2034 Senior Notes, at any time and from time to time, at a redemption price equal to the principal amount of the 2034 Senior Notes being redeemed plus accrued and unpaid interest thereon to the redemption date. On June 13, 2024, the Company completed an underwritten public offering of CAD $500,000,000 aggregate principal amount of 4.50% Senior Notes due June 14, 2029 (the “New 2029 Senior Notes” and, together with the 2028 Senior Notes, the 2029 Senior Notes, the 2030 Senior Notes, the 2032 Senior Notes, the New 2032 Senior Notes, the 2033 Senior Notes, the 2034 Senior Notes, the 2050 Senior Notes and the 2052 Senior Notes, the “Senior Notes”). The New 2029 Senior Notes were issued under the Indenture, as supplemented by the Ninth Supplemental Indenture, dated as of June 13, 2024. The Company is amortizing a $245 debt discount and $2,656 of debt issuance costs through the maturity date of the New 2029 Senior Notes. The Company may, prior to May 14, 2029 (one month before the maturity date) (the “New 2029 Senior Notes Par Call Date”), redeem some or all of the New 2029 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 New 2029 Senior Notes redeemed, and the sum of the present values of the remaining scheduled payments of principal and interest (not including any portion of the payments of interest accrued as of the date of redemption) on the New 2029 Senior Notes redeemed discounted to the redemption date (assuming the New 2029 Senior Notes matured on the New 2029 Senior Notes Par Call Date), plus, in either case, accrued and unpaid interest, if any, thereon to, but excluding, the redemption date. Commencing on May 14, 2029 (one month before the maturity date), the Company may redeem some or all of the New 2029 Senior Notes, at any time and from time to time, at a redemption price equal to the principal amount of the New 2029 Senior Notes being redeemed plus accrued and unpaid interest thereon, but excluding, to the redemption date. 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 accrued and unpaid interest, if any, 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. 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, 2024, aggregate contractual future principal payments by calendar year on long-term debt are due as follows: ​ ​ ​ ​ ​ 2025 $ 7,851 2026 ​ 7,249 2027 ​ 6,030 2028 ​ 504,864 2029 ​ 3,016,290 Thereafter ​ 4,609,429 ​ ​ $ 8,151,713 ​

FAIR VALUE OF FINANCIAL INSTRUM

FAIR VALUE OF FINANCIAL INSTRUMENTS	12 Months Ended
	Dec. 31, 2024
FAIR VALUE OF FINANCIAL INSTRUMENTS
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, 2024 and 2023, 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 and bank time deposits. 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 U.S. government securities, agency securities and Canadian bankers’ acceptance notes. The Company’s assets and liabilities measured at fair value on a recurring basis at December 31, 2024 and 2023, were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurement at December 31, 2024 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 asset position ​ $ 13,929 ​ $ — ​ $ 13,929 ​ $ — Restricted cash ​ $ 135,807 ​ $ 135,807 ​ $ — ​ $ — Restricted investments ​ $ 77,900 ​ $ — ​ $ 77,900 ​ $ — Contingent consideration ​ $ (87,162) ​ $ — ​ $ — ​ $ (87,162) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurement at December 31, 2023 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 asset position ​ $ 22,787 ​ $ — ​ $ 22,787 ​ $ — Restricted cash ​ $ 105,639 ​ $ 105,639 ​ $ — ​ $ — Restricted investments ​ $ 70,658 ​ $ — ​ $ 70,658 ​ $ — Contingent consideration ​ $ (115,030) ​ $ — ​ $ — ​ $ (115,030) ​ ​ The following table summarizes the changes in the fair value for Level 3 liabilities related to contingent consideration for the years ended December 31, 2024 and 2023: ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2024 2023 Beginning balance $ 115,030 ​ $ 81,415 Contingent consideration recorded at acquisition date 28,885 ​ 13,450 Payment of contingent consideration recorded at acquisition date (27,743) ​ (13,317) Payment of contingent consideration recorded in earnings (35,035) ​ — Adjustments to contingent consideration ​ (3) ​ ​ 30,367 Interest accretion expense 6,217 ​ 3,115 Foreign currency translation adjustment (189) ​ — Ending balance $ 87,162 ​ $ 115,030 ​

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	12 Months Ended
	Dec. 31, 2024
COMMITMENTS AND CONTINGENCIES.
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, 2024 and 2023, the Company had provided customers and various regulatory authorities with surety bonds in the aggregate amounts of approximately $934,330 and $901,283, respectively, to secure its asset closure and retirement requirements and $1,077,021 and $743,816, 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 $492,711 and $470,416 were outstanding as of December 31, 2024 and 2023, 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, 2024, the Company’s unconditional purchase obligations consist of multiple fixed-price fuel purchase contracts under which it has 59.7 million gallons remaining to be purchased for a total of $179,272. These fuel purchase contracts expire on or before September 30, 2029. During the years ended December 31, 2024, 2023 and 2022, the Company paid $139,973, $145,598 and $112,136, respectively, under the respective fuel purchase contracts then outstanding. As of December 31, 2024, future minimum purchase commitments, by calendar year, are as follows: ​ ​ ​ ​ ​ 2025 $ 140,123 2026 ​ 37,284 2027 ​ ​ 778 2028 ​ ​ 621 2029 ​ ​ 466 Thereafter ​ ​ — ​ ​ $ 179,272 ​ 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, 2024 and 2023, the current portion of remediation reserves was $8,808 and $10,860, respectively, which is included in Accrued liabilities in the Consolidated Balance Sheets. At December 31, 2024 and 2023, the long-term portion of remediation reserves was $7,186 and $4,289, 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 or sought 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 for disclosing environmental matters involving a governmental authority and 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, 2024, 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. Jefferson Parish, Louisiana Landfill Litigation Between June 2016 and December 31, 2020, one of the Company’s subsidiaries, Louisiana Regional Landfill Company (“LRLC”), conducted certain operations at a municipal solid waste landfill known as the Jefferson Parish Landfill (the “JP Landfill”), located in Avondale, Louisiana, near the City of New Orleans. LRLC’s operations were governed by an Operating Agreement entered into in May 2012 by LRLC under its previous name, IESI LA Landfill Corporation, and the owner of the JP Landfill, Jefferson Parish (the “Parish”). The Parish also holds the State of Louisiana permit for the operation of the JP Landfill. Aptim Corporation, and later River Birch, LLC, operated the landfill gas collection system at the JP Landfill under a separate contract with the Parish. In July and August 2018, four separate lawsuits seeking class action status were filed against LRLC and certain other Company subsidiaries, the Parish, and Aptim Corporation in Louisiana state court, and subsequently removed to the United States District Court for the Eastern District of Louisiana, before Judge Susie Morgan in New Orleans. The court later consolidated the claims of the putative class action plaintiffs (the “ Ictech-Bendeck Addison Addison Addison Addison Addison The Ictech-Bendeck Ictech-Bendeck The court held an eight-day trial on general causation during January and February 2022. On November 29, 2022, the court issued a 45-page decision on the general causation trial. The court concluded that all putative class plaintiffs established general causation—specifically that emissions and gases from the JP Landfill were capable of causing certain damages alleged by the plaintiffs. The court held that it only needed to determine the level of exposure necessary to result in injuries and that the level existed somewhere offsite, and that it was not required to delineate this level of exposure within a geographic area. The court did, however, limit the time period for damages, to between July 2017 and December 2019, and the types of alleged injuries for which the plaintiffs are able to seek damages, to headaches, nausea, vomiting, loss of appetite, sleep disruption, dizziness, fatigue, anxiety and worry, a decrease in quality of life, and loss of enjoyment or use of property. After the general causation decision, extensive discovery occurred in 2023 and 2024. On May 15, 2024, the Ictech-Bendeck On August 8, 2024, Jefferson Parish and the Ictech-Bendeck Ictech-Bendeck the Ictech-Bendeck The Company believes it has defenses to certification of the putative class actions and is continuing to vigorously defend itself; however, at this time, the Company is not able to determine the likelihood of any outcome regarding the underlying claims in the class action, including the allocation of any potential liability among the Company, the Parish, and Aptim Corporation. 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 “CC Landfill”). The CC Landfill has operated since 1972, and as a regional landfill, accepted approximately 2.25 million tons of materials for disposal and beneficial use in 2024. The CC Landfill was the second largest landfill in the County and played a vital role in the County’s ability to safely and quickly gather, process, and dispose of thousands of tons of waste, six days a week. The Application requested expansion of the existing waste footprint on CCL’s contiguous property, an increase in maximum elevation, creation of a new entrance and new 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 reduced the historical landfill operations and represented 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 (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. Following extensive litigation in 2018 and 2019 on the permissible scope of CCL’s challenge, 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 CC Landfill. On October 11, 2022, CCL and the County entered into a settlement agreement that requires CCL to file a CUP modification application with the County embodying the terms of the settlement agreement. CCL filed the CUP modification application on November 10, 2022, an addendum to CCL’s environmental impact report in accordance with the California Environmental Quality Act on January 12, 2024, and a revised addendum on September 30, 2024. The next steps contemplated by the settlement agreement include: completion of review by the County; scheduling the CUP modification application for a hearing before the Los Angeles County Regional Planning Commission; if appealed, a hearing before the County Board of Supervisors; and, upon approval by the County Board of Supervisors of the CUP modification application and satisfaction of certain other contingencies, CCL would dismiss this lawsuit. At a meeting between the County and the Company on September 23, 2024, the County first stated that it would not be possible to complete the environmental review and present the CUP modification to the Regional Planning Commission in 2024. Absent approval of the modified CUP, beginning January 1, 2025, the CUP requires CCL to reduce its maximum annual solid waste tonnage capacity from approximately two million tons of solid waste per year to approximately one million tons of solid waste per year. CCL and the County are required under the settlement agreement to cooperate to take additional lawful and reasonable measures to effectuate the basic terms and goals of the settlement agreement, which include modifying this tonnage reduction to a gradual step-down in tonnage. However, because the County was unable to fully implement the settlement agreement or provide a viable alternative solution to address the severe tonnage restrictions that took effect on January 1, 2025, maintaining ongoing operations at the Landfill was no longer economically viable. Thus, CCL closed active waste disposal operations as of December 31, 2024. On January 10, 2025, CCL and the County appeared before the Superior Court for a trial setting conference and the Court set the remaining claims for a bench trial, beginning October 13, 2025. At this time, 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 CC 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 the noncompliance fee of $0.75. The court indicated that the NOV case would be coordinated with the CUP lawsuit. On October 11, 2022, CCL and the County entered into the settlement agreement, described above under paragraph A. However, as described above, CCL has now closed the Chiquita Canyon Landfill for the acceptance of waste as of December 31, 2024, and CCL’s remaining claims have been set for trial. A status conference and order to show cause in this case is currently set for May 8, 2025. At this time, the Company is not able to determine the likelihood of any outcome in this matter. Elevated Temperature Landfill Event Beginning in May 2023, the Company’s subsidiary, Chiquita Canyon, LLC (“CCL”), began receiving notices of violation (“NOVs”) from the South Coast Air Quality Management District (“SCAQMD”) for alleged violations of Section 41700 of the California Health & Safety Code and SCAQMD Rule 402 based on complaints from the public of odors, which SCAQMD inspectors stated that they verified were from the Chiquita Canyon Landfill (the “CC Landfill”). Each Rule 402 NOV alleges the CC Landfill is “discharging such quantities of air contaminants to cause injury, detriment, nuisance or annoyance to a considerable number of persons.” CCL’s retained expert consultants in Elevated Temperature Landfill (“ETLF”) events have attributed the odors and other impacts to an ETLF event that is occurring in a lined, non-active area of the CC Landfill. Since May 2023, CCL has received approximately 301 NOVs for alleged violations of SCAQMD Rule 402. CCL has also received sixteen additional NOVs from SCAQMD alleging violations of the Stipulated Order for Abatement, the California Health & Safety Code, other SCAQMD rules, and CCL’s Title V permit. On August 15, 2023, SCAQMD petitioned its Hearing Board for an Order for Abatement in Hearing Board Case No. 6177-4 to address the Rule 402 NOVs issued by SCAQMD inspectors as a result of the ETLF event. SCAQMD and CCL negotiated a Stipulated Order for Abatement (the “Stipulated Order”), which was issued by the Hearing Board on September 6, 2023. Modifications to the Stipulated Order were approved by the Hearing Board after hearings on January 16 and 17, March 21, April 24, August 17, 20, and 27, and November 13, 2024. The modified Stipulated Order contains 96 conditions. The next status and modification hearing is scheduled for April 16 and 17, 2025. On November 22, 2023, CCL received an NOV from the Los Angeles Regional Water Quality Control Board (“Water Board”) for alleged violations of CCL’s Waste Discharge Requirements Order No. R4-2018-0172, including the Monitoring and Reporting Program. The allegations relate to increased leachate production and leachate seeps caused by the ETLF event. CCL has received three more NOVs from the Water Board regarding alleged discharges, reporting, and other compliance violations. CCL has submitted full responses to each of the November 22, 2023, and January 24, March 28, and April 9, 2024 NOVs from the Water Board. On June 27, 2024, CCL received a fifth NOV from the Water Board for alleged non-compliance with a March 20, 2024 Investigative Order issued by the Water Board pursuant to California Water Code §§ 13267 and 13383. CCL has provided a full response to the alleged violations. On February 15 and March 29, 2024, CCL received two Summaries of Violations (“SOV”) from the Department of Toxic Substances Control (“DTSC”). The SOVs allege violations of California’s hazardous waste control laws and their implementing regulations related to three incidents in which offsite shipments of leachate, which tested above a regulatory threshold, were shipped to non-hazardous waste treatment and disposal facilities. CCL has submitted full responses to both SOVs from DTSC. On June 4, 2024, CCL received a Finding of Violation (“FOV”) from the U.S. Environmental Protection Agency, alleging violations of the New Source Performance Standards (“NSPS”) and National Emission Standards for Hazardous Air Pollutants (“NESHAP”) for municipal solid waste landfills, the NSPS and NESHAP General Provisions, and certain conditions of CCL’s Title V permit. CCL has submitted a full response to the alleged violations. At this time, CCL is not able to determine the likely penalties that the regulatory agencies will seek for these alleged violations, but they could be substantial. CCL also is incurring substantial costs in conjunction with efforts to address the ETLF event and any related impacts, including attendant air emissions, and to manage the increased production and changing composition of the liquids. At this time, the Company is not able to determine the likelihood of any outcome of the resolution of these alleged violations, including the amount of penalties. In addition to, and distinct from these alleged violations, CCL had been seeking regulatory approvals to allow the use of new cells needed for waste disposal within the CC Landfill’s existing waste footprint permitted under the CUP. However, the Water Board had not yet granted the final approval needed for CCL to access otherwise permitted and constructed airspace when the CC Landfill closed to active waste disposal operations as of December 31, 2024. Chiquita Canyon Landfill Civil Litigation Given the facts related to the ETLF event and the alleged violations described above, a number of civil lawsuits have been filed against CCL and other Company subsidiaries, including Chiquita Canyon, Inc., Waste Connections of California, Inc., Waste Connections Management Services Inc. and Waste Connections US, Inc. These began with Howse et al. v. Chiquita Canyon, LLC, et al. (Los Angeles Co. Superior Court; filed September 5, 2023, removed to U.S.D.C. C.D. Cal. October 4, 2023). That case included class action claims, but in May 2024, those claims were dropped and the case continues as a mass tort case in federal district court. In November 2024, Judge Frimpong in the Central District of California consolidated Howse . There are approximately 9,200 total plaintiffs in these civil lawsuits as of February 5, 2025, which includes some from cases filed but not yet served, and the Company expects additional complaints and plaintiffs in the future. The claims in the ongoing cases allege, among other things, nuisance odors, chemical exposures and other torts, including private nuisance (continuing and permanent), public nuisance (continuing and permanent), negligence, negligence per se, strict liability for ultrahazardous activities, and a violation of Health and Safety Code § 41700. Plaintiffs seek damages for physical injury, fear of future physical injury, increased risk of future injury, including the need for medical monitoring, emotional distress, harm to real and personal property, medical expenses, relocation expenses, and punitive damages. Plaintiffs seek all costs of suits and attorneys’ fees. Some of the cases allege that officers and directors and/or agents of the Company’s subsidiaries had advance knowledge that failure to properly maintain and operate the CC Landfill would result in the sorts of harms that the plaintiffs allegedly suffered. Some of the cases seek injunctive relief to prevent further harm to the plaintiffs or to close the CC Landfill. The additional cases include: Suggs et al. v. Chiquita Canyon, LLC, et al. (Los Angeles Superior Court; filed February 2, 2024, removed to U.S.D.C. C.D. Cal. March 25, 2024)‎; Siryani et al. v. Chiquita Canyon, LLC, et al. (Los Angeles Superior Court; filed March 27, 2024, removed to U.S.D.C. C.D. Cal. on April 29, 2024)‎; Adams Evans et al. v. Chiquita Canyon, LLC et al. (Los Angeles Superior Court; filed April 15, 2014, removed to U.S.D.C. C.D. Cal. on July 5, 2024)‎; Aleksanyan et al. v. Chiquita Canyon, LLC et al. (U.S.D.C. C.D. Cal.; filed May 20, 2024); Jolene Acosta et al., v. Chiquita Canyon, LLC et al. (Los Angeles Superior Court; filed May 29, 2024, removed to U.S.D.C. C.D. Cal. on July 12, 2024); Quaiden Fenstermaker et. al. v. Chiquita Canyon, LLC et al. (Los Angeles Superior Court; filed May 29, 2024, removed to U.S.D.C. C.D. Cal. on July 13, 2024)‎; Briana Mejia et al. v. Chiquita Canyon, LLC et al. (Los Angeles Superior Court; filed May 29, 2024, removed to U.S.D.C. C.D. Cal. on July 15, 2024); Araiza et al. v. Chiquita Canyon, LLC et al. (U.S.D.C. C.D. Cal.; filed June 3, 2024); Melineh Gasparians et al. v. Chiquita Canyon, LLC et al. (Los Angeles Superior Court; filed June 10, 2024; removed to U.S.D.C. C.D. Cal. on September 4, 2024); Claudia Rivera et al. v. Chiquita Canyon, LLC et al. (Los Angeles Superior Court; filed June 14, 2024, removed to U.S.D.C. C.D. Cal. on July 22, 2024)‎; Alejandra Suarez et al. v. Chiquita Canyon, LLC et al. (Los Angeles Superior Court; filed June 20, 2024; removed to U.S.D.C. C.D. Cal. on July 29, 2024) ; ‎ Geon Hwang, et al. v. Chiquita Canyon, LLC et al. (U.S.D.C. C.D. Cal.; filed July 8, 2024); Anabel Austin, et al. v. Chiquita Canyon, LLC et al. (Los Angeles Superior Court; filed July 9, 2024; removed to U.S.D.C. C.D. Cal. on August 16, 2024); Isabell ‎Dolores Palomino et al. v. Chiquita Canyon, LLC et al. (U.S.D.C. C.D. Cal.; filed July 12, 2024); Stephanie Audish et al. v. Chiquita Canyon, LLC (Los Angeles Superior Court; filed July 16, 2024); Scott Benjamin Siegal et. al. v. Chiquita Canyon, LLC et al. (Los Angeles Superior Court; filed July 16, 2024); Alina Hakopyan et al. v. Chiquita Canyon, LLC (Los Angeles Superior Court; filed August 6, 2024); Kaiden Alim et al. v. Chiquita Canyon, LLC et al. (Los Angeles Superior Court, filed September 27, 2024); Nicholas Difatta et al. v. Chiquita Canyon, LLC et al. (Los Angeles Superior Court, filed October 5, 2024); Jane Chun-Won Yang et al. v. Chiquita Canyon, LLC et al. . . Three cases have been filed, but not yet served: K.E. et al. v. Chiquita Canyon, LLC et al. The Company is continuing to vigorously defend itself in these lawsuits; however, at this time, the Company is not able to determine the likelihood of any outcome regarding the underlying claims. County of Los Angeles Litigation The County’s lawsuit alleges public nuisance under California statutes and Los Angeles County ordinances, public nuisance per se, and unfair business practices related to the alleged violation of ordinances referenced in the public nuisance claims. The County seeks an injunction to bring the CC Landfill into compliance with all local, state, and federal laws and regulations, including all necessary measures to “contain and extinguish” the ETLF, prevent odors and gases from reaching any residential zone, and eliminate leachate seeps; subsidize the relocation of affected citizens living near the Landfill; and subsidize mitigation measures undertaken by affected citizens living, working, or studying near the Landfill, such as the purchase of air purification systems, double paned windows, home hardening, and assistance with utility bills. Alternatively, the County requests the appointment of a receiver to take possession and control of the Landfill. The County also seeks to recover civil penalties and attorney’s fees. The Company is not able to determine the potential penalty amount that the County will seek in this lawsuit. The Company is continuing to vigorously defend itself in these lawsuits; however, at this time, the Company is not able to determine the likelihood of any outcome regarding the underlying claims. Collective Bargaining Agreements As of December 31, 2024, 3,774 employees, or approximately 16% of the Company’s workforce, were employed under collective bargaining agreements. The Company has 25 collective bargaining agreements covering 1,603 employees, or approximately 7% of its workforce, that have expired or are set to expire in 2025. The Company does not expect any significant disruption in its overall business in 2025 as a result of labor negotiations, employee strikes or organizational efforts.

Shareholders' Equity

Shareholders' Equity	12 Months Ended
	Dec. 31, 2024
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 29,256 of the Company’s common shares for $4,486 during the year ended December 31, 2024. Under the ESPP, employees purchased 29,808 of the Company’s common shares for $3,909 during the year ended December 31, 2023. Under the ESPP, employees purchased 26,582 of the Company’s common shares for $3,270 during the year ended December 31, 2022. 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 2024, the Company announced that its Board of Directors increased its regular quarterly cash dividend by $0.03, from $0.285 to $0.315 per Company common share. Cash dividends of $302,258, $270,604 and $243,013 were paid during the years ended December 31, 2024, 2023 and 2022, respectively. Normal Course Issuer Bid On July 23, 2024, 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 12,901,981 of the Company’s common shares during the period of August 12, 2024 to August 11, 2025 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, 2024. The Company received TSX approval for its annual renewal of the NCIB on August 6, 2024. 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 are limited to a maximum of 60,089 common shares, which represents 25% of the average daily trading volume on the TSX of 240,359 common shares for the period from February 1, 2024 to July 31, 2024. 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, any share buyback taxes applicable and overall market conditions. All common shares purchased under the NCIB will be immediately cancelled following their repurchase. For each of the years ended December 31, 2024 and 2023, the Company did not repurchase any common shares pursuant to the NCIB in effect during that period. For the year ended December 31, 2022, the Company repurchased 3,388,155 common shares pursuant to the NCIB in effect during that period at an aggregate cost of $424,999. As of December 31, 2024, the maximum number of shares available for repurchase under the current NCIB was 12,901,981. 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, 2024, the Company has reserved the following common shares for issuance: ​ ​ ​ ​ For outstanding RSUs, PSUs and warrants 2,083,109 For future grants under the 2016 Incentive Award Plan 1,993,310 For future grants under the Employee Share Purchase Plan ​ 903,541 ​ 4,979,960 ​ Common Shares Held in Trust Common shares held in trust at December 31, 2024 consist of 48,098 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, 2024, 2023 and 2022, the Company sold 11,344, 6,017 and 5,203 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, 2024, 2023 and 2022, 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, 2024, 2023 and 2022, 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. The 2014 Plan and the Consultant Plan have each automatically terminated. 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. 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, ​ 2024 2023 2022 Weighted average grant-date fair value of restricted share units granted ​ $ 164.93 ​ $ 133.65 ​ $ 121.26 Total fair value of restricted share units vested ​ $ 39,745 ​ $ 39,754 ​ $ 28,751 ​ A summary of activity related to RSUs during the year ended December 31, 2024, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ Grant Date Fair ​ Unvested Shares ​ Value Per Share Outstanding at December 31, 2023 936,267 ​ $ 120.97 Granted 371,343 ​ $ 164.93 Forfeited (51,520) ​ $ 138.91 Vested and issued (343,530) ​ $ 115.69 Outstanding at December 31, 2024 912,560 ​ $ 139.83 ​ 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, 2024, 2023 and 2022, the Company had 29,980, 49,129 and 81,352 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, ​ 2024 2023 2022 Weighted average grant-date fair value of PSUs granted ​ $ 138.29 ​ $ 133.83 ​ $ 117.94 Total fair value of PSUs vested ​ $ 14,948 ​ $ 20,196 ​ $ 4,674 ​ A summary of activity related to PSUs during the year ended December 31, 2024, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ Grant Date Fair ​ Unvested Shares ​ Value Per Share Outstanding at December 31, 2023 259,532 ​ $ 113.68 Granted 113,166 ​ $ 138.29 Vested and issued (153,555) ​ $ 97.35 Outstanding at December 31, 2024 219,143 ​ $ 137.83 ​ During the year ended December 31, 2024, 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, 2026. During the year ended December 31, 2023, 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, 2025. During the year ended December 31, 2022, 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, 2024. 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, 2024, expire between 2025 and 2029. A summary of warrant activity during the year ended December 31, 2024, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ Warrants ​ Exercise Price Outstanding at December 31, 2023 817,873 ​ $ 127.85 Granted 301,719 ​ $ 171.51 Forfeited (153,306) ​ $ 133.59 Exercised (44,860) ​ $ 107.04 Outstanding at December 31, 2024 921,426 ​ $ 142.21 ​ The following table summarizes information about warrants outstanding as of December 31, 2024 and 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value of ​ ​ ​ ​ ​ ​ Warrants ​ ​ ​ Warrants ​ Outstanding at December 31, Grant Date ​ Issued ​ Exercise Price ​ Issued ​ 2024 ​ 2023 Throughout 2019 ​ 151,008 ​ $74.25 to $95.61 ​ $ 2,634 ​ — ​ 25,490 Throughout 2020 ​ 164,890 ​ $72.65 to $104.89 ​ $ 3,140 ​ 85,293 ​ 145,586 Throughout 2021 ​ 218,166 ​ $99.33 to $135.97 ​ $ 5,584 ​ 191,155 ​ 191,155 Throughout 2022 ​ 380,478 ​ $125.32 to $143.95 ​ $ 12,972 ​ 289,276 ​ 326,085 Throughout 2023 ​ 129,557 ​ $129.75 to $142.93 ​ $ 5,133 ​ 106,649 ​ 129,557 Throughout 2024 ​ 301,719 ​ $149.27 to $192.47 ​ $ 14,651 ​ 249,053 ​ — ​ ​ ​ ​ ​ ​ ​ 921,426 817,873 ​ Deferred Share Units A summary of the Company’s deferred share units (“DSUs”) activity is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2024 ​ 2023 2022 Weighted average grant-date fair value of DSUs granted ​ $ 168.71 ​ $ 136.47 ​ $ 121.00 Total fair value of DSUs awarded ​ $ 632 ​ $ 538 ​ $ 253 ​ 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, 2024, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ Grant Date Fair ​ Vested Shares ​ Value Per Share Outstanding at December 31, 2023 30,481 ​ $ 77.34 Granted 3,746 ​ $ 168.71 Cash settled (9,207) ​ $ 61.65 Share settled (4,602) ​ $ 94.15 Outstanding at December 31, 2024 20,418 ​ $ 97.38 ​ 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 or other distribution events. A summary of activity related to Progressive Waste RSUs during the year ended December 31, 2024, is presented below: ​ ​ ​ ​ Outstanding at December 31, 2023 51,812 Cash settled (6,346) Outstanding at December 31, 2024 45,466 ​ 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.

Other Comprehensive Income (Los

Other Comprehensive Income (Loss)	12 Months Ended
	Dec. 31, 2024
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, 2024, 2023 and 2022, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2024 ​ Gross Tax Effect Net of Tax Interest rate swap amounts reclassified into interest expense ​ $ (20,467) ​ $ 5,424 ​ $ (15,043) Changes in fair value of interest rate swaps ​ 11,607 ​ (3,076) ​ 8,531 Foreign currency translation adjustment ​ (189,402) ​ — ​ (189,402) ​ ​ $ (198,262) ​ $ 2,348 ​ $ (195,914) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2023 ​ Gross Tax Effect Net of Tax Interest rate swap amounts reclassified into interest expense ​ $ (19,607) ​ $ 5,196 ​ $ (14,411) Changes in fair value of interest rate swaps ​ 10,588 ​ (2,806) ​ 7,782 Foreign currency translation adjustment ​ 53,633 ​ — ​ 53,633 ​ ​ $ 44,614 ​ $ 2,390 ​ $ 47,004 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2022 ​ Gross Tax Effect Net of Tax Interest rate swap amounts reclassified into interest expense ​ $ 6,551 ​ $ (1,736) ​ $ 4,815 Changes in fair value of interest rate swaps ​ 76,336 ​ (20,229) ​ 56,107 Foreign currency translation adjustment ​ ​ (157,336) ​ ​ — ​ ​ (157,336) ​ ​ $ (74,449) ​ $ (21,965) ​ $ (96,414) ​ 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, 2022 ​ $ 23,378 ​ $ (80,208) ​ $ (56,830) Amounts reclassified into earnings ​ (14,411) ​ — ​ (14,411) Changes in fair value ​ 7,782 ​ — ​ 7,782 Foreign currency translation adjustment ​ — ​ 53,633 ​ 53,633 Balance at December 31, 2023 ​ ​ 16,749 ​ ​ (26,575) ​ ​ (9,826) Amounts reclassified into earnings ​ ​ (15,043) ​ ​ — ​ ​ (15,043) Changes in fair value ​ ​ 8,531 ​ ​ — ​ ​ 8,531 Foreign currency translation adjustment ​ ​ — ​ ​ (189,402) ​ ​ (189,402) Balance at December 31, 2024 ​ $ 10,237 ​ $ (215,977) ​ $ (205,740) ​

INCOME TAXES

INCOME TAXES	12 Months Ended
	Dec. 31, 2024
INCOME TAXES
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, ​ 2024 2023 2022 U.S. ​ $ 343,255 ​ $ 622,041 ​ $ 734,126 Non – U.S. ​ 419,678 ​ 361,460 ​ 314,837 Income before income taxes ​ $ 762,933 ​ $ 983,501 ​ $ 1,048,963 ​ The provision for income taxes consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2024 2023 2022 Current: ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. Federal ​ $ 95,007 ​ $ 120,420 ​ $ 59,675 State ​ 42,725 ​ 50,713 ​ 28,770 Non – U.S. ​ 65,916 ​ 43,213 ​ 31,036 ​ ​ 203,648 ​ 214,346 ​ 119,481 Deferred: ​ ​ ​ U.S. Federal ​ (33,507) ​ 14,130 ​ 95,397 State ​ (5,833) ​ (1,931) ​ 16,840 Non – U.S. ​ (17,945) ​ (5,870) ​ (18,756) ​ ​ (57,285) ​ 6,329 ​ 93,481 Provision for income taxes ​ $ 146,363 ​ $ 220,675 ​ $ 212,962 ​ 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, ​ 2024 2023 2022 U.S. federal statutory rate ​ 21.0 % 21.0 % 21.0 % State taxes, net of federal benefit 4.1 4.3 4.2 ​ Deferred income tax liability adjustments 0.7 0.3 — ​ Effect of international operations (3.8) (3.9) (4.0) ​ Federal tax credits (1.5) — (0.1) ​ Share-based compensation (0.7) (0.3) (0.2) ​ Other (0.6) 1.0 (0.6) ​ ​ 19.2 % 22.4 % 20.3 % ​ 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. The significant components of deferred income tax assets and liabilities, reduced by valuation allowances as applicable, are presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2024 2023 Deferred income tax assets: ​ ​ Accrued expenses ​ $ 38,674 ​ $ 33,358 Compensation ​ 26,589 ​ 25,781 Contingent liabilities ​ 16,237 ​ 27,154 Tax credits and loss carryforwards ​ 15,477 ​ 23,877 Landfill closure and post-closure ​ ​ 90,240 ​ ​ 12,476 Finance costs ​ 4,032 ​ 6,968 Other ​ ​ 13,306 ​ ​ 14,036 Gross deferred income tax assets ​ 204,555 ​ 143,650 Less: Valuation allowance ​ — ​ — Total deferred income tax assets ​ 204,555 ​ 143,650 ​ ​ ​ ​ ​ ​ ​ Deferred income tax liabilities: ​ ​ ​ ​ ​ ​ Goodwill and other intangibles ​ (472,608) ​ (471,074) Property and equipment ​ (595,156) ​ (602,453) Prepaid expenses ​ (19,737) ​ (15,428) Investment in subsidiaries ​ (71,703) ​ (71,136) Interest rate swaps ​ (3,691) ​ (6,039) Total deferred income tax liabilities ​ (1,162,895) ​ (1,166,130) Net deferred income tax liability ​ $ (958,340) ​ $ (1,022,480) ​ The Company has $14,901 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, 2024, the Company had undistributed earnings of approximately $4,078,543 for which income taxes have not been provided on permanently reinvested earnings of approximately $2,903,543. Additionally, the Company has not recorded deferred taxes on the amount of financial reporting basis in excess of tax basis of approximately $401,204 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 2020. Additionally, the normal reassessment period for the Company has expired for all Canadian federal income tax matters for years through 2019. The Company did not have any unrecognized tax benefits recorded at December 31, 2024, 2023 or 2022. The Company does not anticipate the total amount of unrecognized tax benefits will significantly change by December 31, 2025. 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, 2024
SEGMENT REPORTING
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 single contract or customer accounted for more than 10% of the Company’s total revenues at the consolidated or reportable segment level during the periods presented. The Company manages its operations through the following six geographic solid waste operating segments: Western, Southern, Eastern, Central, Canada and MidSouth. The Company’s six 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. Certain corporate or regional overhead expense allocations may affect comparability of the segment information presented herein on a period-over-period basis. The Company’s Chief Operating Decision Maker (“CODM”) is the Company’s President and Chief Executive Officer. The CODM 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 and other income (expense). 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. Summarized financial information concerning the Company’s reportable segments for the years ended December 31, 2024, 2023 and 2022, is shown in the following tables: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2024 Western Southern Eastern Central Canada MidSouth Corporate (a), (f) Consolidated Revenue ​ $ 2,034,370 ​ $ 1,984,150 ​ $ 1,875,559 ​ $ 1,696,559 ​ $ 1,385,869 ​ $ 1,218,482 ​ $ — ​ $ 10,194,989 ​ Intercompany revenue (b) ​ ​ (235,701) ​ ​ (226,957) ​ ​ (311,348) ​ ​ (181,657) ​ ​ (124,889) ​ ​ (194,846) ​ ​ — ​ ​ (1,275,398) ​ Reported revenue ​ 1,798,669 ​ ​ 1,757,193 ​ ​ 1,564,211 ​ ​ 1,514,902 ​ ​ 1,260,980 ​ ​ 1,023,636 ​ ​ — ​ 8,919,591 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment expenses (c) ​ ​ (1,277,911) ​ ​ (1,200,768) ​ ​ (1,146,988) ​ ​ (972,101) ​ ​ (709,501) ​ ​ (740,227) ​ ​ (27,655) ​ ​ (6,075,151) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment EBITDA (d) ​ 520,758 ​ ​ 556,425 ​ ​ 417,223 ​ ​ 542,801 ​ ​ 551,479 ​ ​ 283,409 ​ ​ (27,655) ​ 2,844,440 ​ Segment EBITDA margin ​ 29.0 % ​ 31.7 % ​ 26.7 % ​ 35.8 % ​ 43.7 % ​ 27.7 % ​ ​ ​ 31.9 % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Depreciation and amortization ​ ​ (211,111) ​ ​ (203,445) ​ ​ (230,466) ​ ​ (170,424) ​ ​ (200,274) ​ ​ (138,671) ​ ​ (9,378) ​ ​ (1,163,769) ​ Other segment items (e) ​ ​ (596,463) ​ ​ (9,395) ​ ​ (4,398) ​ ​ 1,483 ​ ​ 944 ​ ​ (33) ​ ​ (309,876) ​ ​ (917,738) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Income before income tax provision ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 762,933 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Capital expenditures ​ $ 198,849 ​ $ 190,912 ​ $ 191,817 ​ $ 174,805 ​ $ 147,596 ​ $ 129,373 ​ $ 22,636 ​ $ 1,055,988 ​ Total assets (g) ​ $ 3,512,253 ​ $ 3,885,522 ​ $ 3,544,234 ​ $ 2,827,108 ​ $ 3,564,052 ​ $ 2,022,594 ​ $ 462,046 ​ $ 19,817,809 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 Western Southern Eastern Central Canada MidSouth Corporate (a), (f) Consolidated Revenue ​ $ 1,878,843 ​ $ 1,846,713 ​ $ 1,639,351 ​ $ 1,620,908 ​ $ 1,109,164 ​ $ 1,072,753 ​ $ — ​ $ 9,167,732 ​ Intercompany revenue (b) ​ ​ (209,554) ​ ​ (204,439) ​ ​ (259,118) ​ ​ (180,751) ​ ​ (113,322) ​ ​ (178,597) ​ ​ — ​ ​ (1,145,781) ​ Reported revenue ​ 1,669,289 ​ ​ 1,642,274 ​ ​ 1,380,233 ​ ​ 1,440,157 ​ ​ 995,842 ​ ​ 894,156 ​ ​ — ​ 8,021,951 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment expenses (c) ​ ​ (1,186,084) ​ ​ (1,124,272) ​ ​ (1,027,172) ​ ​ (927,874) ​ ​ (605,178) ​ ​ (648,020) ​ ​ (25,032) ​ ​ (5,543,632) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment EBITDA (d) ​ 483,205 ​ ​ 518,002 ​ ​ 353,061 ​ ​ 512,283 ​ ​ 390,664 ​ ​ 246,136 ​ ​ (25,032) ​ 2,478,319 ​ Segment EBITDA margin ​ 28.9 % ​ 31.5 % ​ 25.6 % ​ 35.6 % ​ 39.2 % ​ 27.5 % ​ ​ ​ 30.9 % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Depreciation and amortization ​ ​ (199,426) ​ ​ (179,948) ​ ​ (207,909) ​ ​ (169,370) ​ ​ (121,326) ​ ​ (117,397) ​ ​ (7,835) ​ ​ (1,003,211) ​ Other segment items (e) ​ ​ (160,351) ​ ​ (11,165) ​ ​ (2,492) ​ ​ 6,763 ​ ​ (2,930) ​ ​ 3,783 ​ ​ (325,215) ​ ​ (491,607) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Income before income tax provision ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 983,501 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Capital expenditures ​ $ 192,148 ​ $ 166,961 ​ $ 143,484 ​ $ 171,748 ​ $ 105,453 ​ $ 135,650 ​ $ 18,556 ​ $ 934,000 ​ Total assets (g) ​ $ 3,432,529 ​ $ 3,501,953 ​ $ 3,228,244 ​ $ 2,811,016 ​ $ 2,794,795 ​ $ 1,705,180 ​ $ 442,159 ​ $ 17,915,876 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2022 Western Southern Eastern Central Canada MidSouth Corporate (a), (f) Consolidated Revenue ​ $ 1,605,574 ​ $ 1,670,864 ​ $ 1,445,193 ​ $ 1,447,703 ​ $ 1,047,672 ​ $ 992,922 ​ $ — ​ $ 8,209,928 ​ Intercompany revenue (b) ​ ​ (177,543) ​ ​ (176,425) ​ ​ (211,498) ​ ​ (159,355) ​ ​ (107,048) ​ ​ (166,200) ​ ​ — ​ ​ (998,069) ​ Reported revenue ​ 1,428,031 ​ ​ 1,494,439 ​ ​ 1,233,695 ​ ​ 1,288,348 ​ ​ 940,624 ​ ​ 826,722 ​ ​ — ​ 7,211,859 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment expenses (c) ​ ​ (1,003,096) ​ ​ (1,027,920) ​ ​ (952,173) ​ ​ (842,033) ​ ​ (591,221) ​ ​ (591,017) ​ ​ (25,019) ​ ​ (5,032,479) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment EBITDA (d) ​ 424,935 ​ ​ 466,519 ​ ​ 281,522 ​ ​ 446,315 ​ ​ 349,403 ​ ​ 235,705 ​ ​ (25,019) ​ 2,179,380 ​ Segment EBITDA margin ​ 29.8 % ​ 31.2 % ​ 22.8 % ​ 34.6 % ​ 37.1 % ​ 28.5 % ​ ​ ​ 30.2 % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Depreciation and amortization ​ ​ (155,882) ​ ​ (175,614) ​ ​ (190,480) ​ ​ (156,895) ​ ​ (118,388) ​ ​ (112,866) ​ ​ (8,835) ​ ​ (918,960) ​ Other segment items (e) ​ ​ (738) ​ ​ (7,330) ​ ​ (4,154) ​ ​ 5,368 ​ ​ (1,118) ​ ​ (3,606) ​ ​ (199,879) ​ ​ (211,457) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Income before income tax provision ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 1,048,963 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Capital expenditures ​ $ 232,714 ​ $ 151,093 ​ $ 138,028 ​ $ 181,065 ​ $ 70,051 ​ $ 133,849 ​ $ 5,877 ​ $ 912,677 ​ Total assets (g) ​ $ 3,239,679 ​ $ 3,410,888 ​ $ 2,752,436 ​ $ 2,803,853 ​ $ 2,773,882 ​ $ 1,727,323 ​ $ 426,542 ​ $ 17,134,603 ​ (a) The majority of Corporate expenses are allocated to the six 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 six 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) Segment expenses consist of all expenses that directly impact the CODM's primary financial measure, segment EBITDA. These expenses include cost of operations and selling, general, and administrative expenses as presented in the Company’s consolidated statements of operations. (d) 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. (e) For all geographic operating segments, other segment items consist of gains and losses on: disposal of assets, disposal of operations, litigation settlements, environmental remediation, real estate leases, landfill closure adjustments, contingent liability adjustments, impairments, foreign currency gains/losses and interest income. See Note 3 for more information relating to landfill closure adjustments and impairments recorded in the Western segment from the Company’s decision to cease active waste disposal operations at its Chiquita Canyon Landfill. (f) Corporate assets include cash, debt issuance costs, equity investments, operating lease right-of-use assets and corporate facility leasehold improvements and equipment. (g) Goodwill is included within total assets for each of the Company’s six operating segments. The following table shows changes in goodwill during the years ended December 31, 2023 and 2024, by reportable segment: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Western Southern Eastern Central Canada MidSouth Total Balance as of December 31, 2022 ​ $ 732,335 ​ $ 1,547,894 ​ $ 1,189,111 ​ $ 1,003,470 ​ $ 1,684,670 ​ $ 744,817 ​ $ 6,902,297 Goodwill acquired ​ 47,120 ​ ​ 11,809 ​ ​ 398,380 ​ ​ 6,461 ​ ​ — ​ ​ 1,366 ​ 465,136 Goodwill acquisition adjustments ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ (2,215) ​ ​ — ​ ​ (2,215) Goodwill divested ​ ​ — ​ ​ — ​ ​ — ​ ​ (1,431) ​ ​ — ​ ​ — ​ ​ (1,431) Impact of changes in foreign currency ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 40,613 ​ ​ — ​ 40,613 Balance as of December 31, 2023 ​ ​ 779,455 ​ ​ 1,559,703 ​ ​ 1,587,491 ​ ​ 1,008,500 ​ ​ 1,723,068 ​ ​ 746,183 ​ ​ 7,404,400 Goodwill acquired ​ 85,147 ​ ​ 17,411 ​ ​ 148,093 ​ ​ 2,074 ​ ​ 343,531 ​ ​ 103,258 ​ 699,514 Impact of changes in foreign currency ​ — ​ — ​ — ​ — ​ (153,508) ​ — ​ (153,508) Balance as of December 31, 2024 ​ $ 864,602 ​ $ 1,577,114 ​ $ 1,735,584 ​ $ 1,010,574 ​ $ 1,913,091 ​ $ 849,441 ​ $ 7,950,406 ​ Property and equipment, net relating to operations in the United States and Canada are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2024 2023 United States ​ $ 6,870,901 ​ $ 6,456,319 Canada ​ 1,165,028 ​ 772,012 Total ​ $ 8,035,929 ​ $ 7,228,331 ​ ​

Net Income Per Share Informatio

Net Income Per Share Information	12 Months Ended
	Dec. 31, 2024
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, 2024, 2023 and 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2024 2023 2022 Numerator: ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income attributable to Waste Connections for basic and diluted earnings per share ​ $ 617,573 ​ $ 762,800 ​ $ 835,662 Denominator: ​ ​ ​ ​ ​ ​ Basic shares outstanding ​ 257,965,871 ​ 257,551,129 ​ 257,383,578 Dilutive effect of equity-based awards ​ 696,319 ​ 598,115 ​ 655,223 Diluted shares outstanding ​ 258,662,190 ​ 258,149,244 ​ 258,038,801 ​

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2024
Employee Benefit Plans [Abstract]
Employee Benefit Plans	19. EMPLOYEE BENEFIT PLANS Retirement Savings Plans: For eligible non-union Canadian employees, Waste Connections and its subsidiaries make a matching contribution to a deferred profit sharing plan (“DPSP”) of up to 5% of the employee’s eligible compensation, subject to certain limitations imposed by the Income Tax Act (Canada). 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 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. Total employer expenses, including employer matching contributions, for the DPSP and 401(k) Plans were $46,489, $42,100 and $37,165, respectively, during the years ended December 31, 2024, 2023 and 2022. 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 2024 2023 (b),(c) 2024 2023 2022 Agreement Western Conference of Teamsters Pension Trust 91-6145047 - 001 Green Green Not applicable ​ $ 9,676 ​ $ 8,747 ​ $ 5,803 12/31/2024 to 6/30/2028 Local 731, I.B. of T., Pension Fund 36-6513567 - 001 Green for the plan year beginning 10/1/2023 Green for the plan year beginning 10/1/2022 Not applicable ​ ​ 5,471 ​ ​ 4,939 ​ ​ 4,484 9/30/2028 Suburban Teamsters of Northern Illinois Pension Fund 36-6155778 - 001 Green Green Not applicable ​ 3,013 ​ 2,671 ​ 2,516 2/28/2029 Teamsters Local 301 Pension Fund 36-6492992 - 001 Green Green Not applicable ​ 1,314 ​ 1,183 ​ 1,310 9/30/2028 Midwest Operating Engineers Pension Plan 36-6140097 - 001 Green for the plan year beginning 4/1/2024 Green for the plan year beginning 4/1/2023 Not applicable ​ 774 ​ 704 ​ 542 10/31/2025 Automobile Mechanics’ Local No. 701 Union and Industry Pension Fund 36-6042061 - 001 Green Green Not applicable ​ 562 ​ 452 ​ 470 12/31/2025 Local 813 Pension Trust Fund 13-1975659 - 001 Critical and Declining for the plan year beginning 1/1/2024 Critical and Declining for the plan year beginning 1/1/2023 Implemented ​ 485 ​ 557 ​ 429 11/30/2027 IAM National Pension Fund 51-6031295 - 002 Critical Critical Implemented ​ 469 ​ 442 ​ 342 12/31/2025 Locals 302 & 612 of the IOUE - Employers Construction Industry Retirement Plan ​ 91-6028571 - 001 ​ Green ​ Green ​ Not applicable ​ ​ 355 ​ ​ 341 ​ ​ 338 ​ 11/30/2026 International Union of Operating Engineers Pension Trust 85512-1 Green as of 4/30/2022 Green as of 4/30/2022 Not applicable ​ 296 ​ 285 ​ 281 3/31/2025 to 3/31/2028 Multi-Sector Pension Plan 1085653 Critical as of 1/1/2022 Critical as of 1/1/2022 Not applicable ​ 274 ​ 246 ​ 249 12/31/2026 Recycling and General Industrial Union Local 108 Pension Fund ​ 13-6366378 - 001 ​ Green ​ Green ​ Not applicable ​ ​ 246 ​ ​ 225 ​ ​ 230 ​ 2/28/2027 Nurses and Local 813 IBT Retirement Plan ​ 13-3628926 - 001 ​ Green ​ Green ​ Not applicable ​ ​ 125 ​ ​ 121 ​ ​ 97 ​ 11/30/2027 Contributions to other multiemployer plans ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 98 ​ ​ 81 ​ ​ 65 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 23,158 ​ $ 20,994 ​ $ 17,156 ​ ​ ​ (a) Unless otherwise noted in the table above, the most recent Pension Protection Act zone status available in 2024 and 2023 is for the plans’ years ended December 31, 2023 and 2022, 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, 2024 and 2023 . (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, 2023, 2022 and 2021; 2) Suburban Teamsters of Northern Illinois Pension Plan for the plan years ending December 31, 2023, 2022 and 2021; 3) Teamsters Local 301 Pension Fund for plan years ending December 31, 2023, 2022 and 2021; 4) Local 813 Pension Trust Fund for the plan year ending December 31, 2023; and 5) Recycling and General Industrial Union Local 108 Pension Fund for the plan years ending December 31, 2023, 2022 and 2021. 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 Event

Subsequent Event	12 Months Ended
	Dec. 31, 2024
Subsequent Events [Abstract]
Subsequent Event	20. SUBSEQUENT EVENT On February 12, 2025, the Company announced that its Board of Directors approved a regular quarterly cash dividend of $0.315 per Company common share. The dividend will be paid on March 13, 2025, to shareholders of record on the close of business on February 27, 2025.

SCHEDULE II - Valuation and Qua

SCHEDULE II - Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2024
Valuation and Qualifying Accounts [Abstract]
Schedule II Valuation and Qualifying Accounts	SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS Years Ended December 31, 2024, 2023 and 2022 (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, 2024 ​ $ 23,553 ​ $ 20,063 ​ $ — ​ $ (17,886) ​ $ 25,730 Year Ended December 31, 2023 ​ $ 22,939 ​ $ 17,504 ​ $ — ​ $ (16,890) ​ $ 23,553 Year Ended December 31, 2022 ​ $ 18,480 ​ $ 17,259 ​ $ — ​ $ (12,800) ​ $ 22,939 ​

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Pay vs Performance Disclosure
Net Income (Loss)	$ 617,573	$ 762,800	$ 835,662

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Dec. 31, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Cybersecurity Risk Management a

Cybersecurity Risk Management and Strategy Disclosure	12 Months Ended
	Dec. 31, 2024
Cybersecurity Risk Management, Strategy, and Governance [Line Items]
Cybersecurity Risk Management Processes for Assessing, Identifying, and Managing Threats [Text Block]	We assess, identify and manage material risks from cybersecurity threats under our enterprise risk assessment framework, as well as several related policies and procedures addressing areas such as threat vulnerability management, cyber risk management, data protection and classification, network security, access control, incident response, security awareness, employee training and asset management. These policies and related standards require identification of all Information Technology (IT) and Operational Technology (OT) critical systems, assets and networks, and sufficient controls for IT and OT asset inventory, including responsibilities for assets, information owners, and asset disposition processes. From a security perspective, our Information Technology and Safety teams are responsible for protecting physical processes, safety, production, efficiency, and protection of employees. Our Information Security team is directed at protecting all aspects of data and how information is stored, transmitted, processed and used in business processes. Our Information Security team of the Information Technology department has the direct responsibility for developing, monitoring and enforcing information security standards and procedures; reviewing and approving all network interconnections for compliance to security standards; and assisting, consulting and training individuals throughout the Company in the use of appropriate information security practices. This group is responsible for ensuring that all IT and OT systems, assets and networks are aligned with the parent company and affiliate cybersecurity framework. We engage independent third-party consultants from time to time to assess the adequacy of our cybersecurity measures and assist in implementing any appropriate actions to address any vulnerabilities identified. The Senior Vice President – Chief Information Officer, or CIO, who reports to the Executive Vice President and Chief Operating Officer, oversees this group and is responsible for managing the program, in collaboration with our business and functions. Our CIO has served in that role with us since 2004 and has extensive experience with cybersecurity and information technology at the Company. Our vendor risk management process includes conducting risk assessments to identify and monitor cybersecurity risks associated with third-party service providers, including threat detection and security event notifications. We also have requirements for third-party service providers which include regulatory compliance and meeting NIST Cybersecurity Framework policy and standards. Our agreements with third-party service providers include cybersecurity provisions to address risks. Our Security Incident Response Plan is updated periodically and reviewed at least annually. This plan includes guidelines for the escalation and communication of cybersecurity incidents, including a requirement to timely report to executive leadership and the Board of Directors based on an assessment of the risk and other specified criteria. We have established a cyber incident response team to prepare for, mitigate and remediate cybersecurity incidents, which is integrated within our enterprise crisis management framework.
Cybersecurity Risk Management Processes Integrated [Flag]	true
Cybersecurity Risk Management Processes Integrated [Text Block]	Cybersecurity risks are integrated into our overall risk management process through the collaboration of the cybersecurity professionals and our risk management functions to assess threat levels at the subsidiary and parent company level and identify steps and resources appropriate to manage such risks.
Cybersecurity Risk Management Third Party Engaged [Flag]	true
Cybersecurity Risk Third Party Oversight and Identification Processes [Flag]	true
Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Flag]	false
Cybersecurity Risk Board of Directors Oversight [Text Block]	Cybersecurity risks are integrated into our overall risk management process through the collaboration of the cybersecurity professionals and our risk management functions to assess threat levels at the subsidiary and parent company level and identify steps and resources appropriate to manage such risks. The Board of Directors oversees the management of risks from cybersecurity threats through regular reports received from the CIO, which include updates on our performance with preparing, preventing, detecting, responding to, mitigating and recovering from cybersecurity incidents. Should a cybersecurity threat or incident pose a significant risk to the Company, our processes provide that the CIO, through the CEO, as appropriate, would promptly inform the Board regarding any such threat or incident. We are regularly the target of attempted cyber and other security threats and must continuously monitor and ‎develop our information technology networks and infrastructure to prevent, detect, address and mitigate the risk of ‎unauthorized access, misuse, computer viruses and other events that could have a security impact.‎ While to date the Company has not detected a significant compromise of its information and operating systems, significant data loss or any material financial losses related to cybersecurity attacks, it is possible that we could experience a significant event in the future. Risks and exposures related to cybersecurity attacks are expected to remain high for the foreseeable future due to the rapidly evolving nature and sophistication of these threats. See Item 1A. Risk Factors, “We are increasingly dependent on technology, including through the use of Artificial Intelligence (AI), in our operations and a failure of our technology could impact our ability ‎to service our customers and adversely affect our financial results, damage our reputation, and expose us to litigation ‎risk.”
Cybersecurity Risk Board Committee or Subcommittee Responsible for Oversight [Text Block]	Board of Directors
Cybersecurity Risk Process for Informing Board Committee or Subcommittee Responsible for Oversight [Text Block]	Our Security Incident Response Plan is updated periodically and reviewed at least annually. This plan includes guidelines for the escalation and communication of cybersecurity incidents, including a requirement to timely report to executive leadership and the Board of Directors based on an assessment of the risk and other specified criteria. We have established a cyber incident response team to prepare for, mitigate and remediate cybersecurity incidents, which is integrated within our enterprise crisis management framework.
Cybersecurity Risk Role of Management [Text Block]	We assess, identify and manage material risks from cybersecurity threats under our enterprise risk assessment framework, as well as several related policies and procedures addressing areas such as threat vulnerability management, cyber risk management, data protection and classification, network security, access control, incident response, security awareness, employee training and asset management. These policies and related standards require identification of all Information Technology (IT) and Operational Technology (OT) critical systems, assets and networks, and sufficient controls for IT and OT asset inventory, including responsibilities for assets, information owners, and asset disposition processes. From a security perspective, our Information Technology and Safety teams are responsible for protecting physical processes, safety, production, efficiency, and protection of employees. Our Information Security team is directed at protecting all aspects of data and how information is stored, transmitted, processed and used in business processes. Our Information Security team of the Information Technology department has the direct responsibility for developing, monitoring and enforcing information security standards and procedures; reviewing and approving all network interconnections for compliance to security standards; and assisting, consulting and training individuals throughout the Company in the use of appropriate information security practices. This group is responsible for ensuring that all IT and OT systems, assets and networks are aligned with the parent company and affiliate cybersecurity framework. We engage independent third-party consultants from time to time to assess the adequacy of our cybersecurity measures and assist in implementing any appropriate actions to address any vulnerabilities identified. The Senior Vice President – Chief Information Officer, or CIO, who reports to the Executive Vice President and Chief Operating Officer, oversees this group and is responsible for managing the program, in collaboration with our business and functions. Our CIO has served in that role with us since 2004 and has extensive experience with cybersecurity and information technology at the Company.
Cybersecurity Risk Management Positions or Committees Responsible [Flag]	true
Cybersecurity Risk Management Positions or Committees Responsible [Text Block]	The Senior Vice President – Chief Information Officer, or CIO
Cybersecurity Risk Management Expertise of Management Responsible [Text Block]	Our CIO has served in that role with us since 2004 and has extensive experience with cybersecurity and information technology at the Company.
Cybersecurity Risk Process for Informing Management or Committees Responsible [Text Block]	The Senior Vice President – Chief Information Officer, or CIO, who reports to the Executive Vice President and Chief Operating Officer, oversees this group and is responsible for managing the program, in collaboration with our business and functions.
Cybersecurity Risk Management Positions or Committees Responsible Report to Board [Flag]	true

New Accounting Standards and _2

New Accounting Standards and Reclassifications (Policy)	12 Months Ended
	Dec. 31, 2024
New Accounting Standards and Reclassifications [Abstract]
New Accounting Pronouncements	Accounting Standards Adopted Disclosure of Significant Segment Expenses and Other Segment Items The Company adopted the amended guidance for its fiscal year 2024 annual financial statements and interim financial statements thereafter and have applied this standard retroactively for all prior periods presented in the financial statements. Accounting Standards Pending Adoption Additional Income Tax Disclosures Disaggregation of Income Statement Expenses standard retrospectively. Early adoption is permitted. The Company does not expect the adoption of this guidance to have a material impact on its consolidated financial statements.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policy)	12 Months Ended
	Dec. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [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. All references to “dollars” or “$” used herein refer to U.S. dollars, and all references to “CAD $” used herein refer to Canadian dollars, unless otherwise stated.
Cash Equivalents	Cash Equivalents The Company considers all highly liquid investments with original maturities of three months or less at purchase to be cash equivalents. As of December 31, 2024 and 2023, 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, ​ 2024 2023 2022 Commercial $ 2,670,549 ​ $ 2,476,891 $ 2,176,295 Residential ​ 2,258,911 ​ ​ 2,125,068 ​ ​ 1,891,108 Industrial and construction roll off ​ 1,403,313 ​ ​ 1,333,020 ​ ​ 1,183,624 Total collection ​ 6,332,773 ​ ​ 5,934,979 ​ ​ 5,251,027 Landfill ​ 1,557,872 ​ ​ 1,483,397 ​ ​ 1,328,942 Transfer ​ 1,349,080 ​ ​ 1,198,385 ​ ​ 1,026,050 Recycling ​ 241,873 ​ ​ 147,039 ​ ​ 204,876 E&P ​ 521,504 ​ ​ 232,211 ​ ​ 210,562 Intermodal and other ​ 191,887 ​ ​ 171,721 ​ ​ 188,471 Intercompany ​ (1,275,398) ​ ​ (1,145,781) ​ ​ (998,069) Total $ 8,919,591 ​ $ 8,021,951 $ 7,211,859 ​ 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, 2024 was recognized as revenue during the three months ended December 31, 2024 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, the method of transportation used 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, such as solid waste collection service contracts, are satisfied over time, and revenue is recognized based on the value provided to the customer during the period. In many of the Company’s markets, solid waste collection service contracts exist as exclusive franchise agreements or municipal contracts. 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. Such contracts are generally within the Company’s collection, recycling and other lines of business and have a weighted average remaining contract life of approximately five years, excluding certain exclusive and perpetual agreements, such as governmental certificates . 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, ​ ​ 2024 2023 Beginning balance ​ $ 23,553 ​ $ 22,939 Current period provision for expected credit losses ​ ​ 20,243 ​ ​ 17,430 Write-offs charged against the allowance ​ ​ (23,141) ​ ​ (22,743) Recoveries collected ​ ​ 5,255 ​ ​ 5,853 Impact of changes in foreign currency ​ ​ (180) ​ ​ 74 Ending balance ​ $ 25,730 ​ $ 23,553
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 Sheets, and are amortized to Selling, general and administrative expense over the estimated life of the relevant customer relationship, which ranges from one Company would have recognized is one year or less. The Company had $28,161 and $25,977 of deferred sales incentives at December 31, 2024 and 2023, respectively. During the years ended December 31, 2024, 2023 and 2022, the Company recorded a total of $25,047, $25,855 and $22,675, 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 5 – 12 years
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 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 layers for final capping, closure and post-closure liabilities is based on its long-term credit adjusted risk-free rate. The Company’s discount rate assumption for purposes of computing 2024 and 2023 “layers” for final capping, closure and post-closure obligations was 5.50% for each of 2024 and 2023. The Company’s long-term inflation rate assumption was 2.75% for each of the years ended December 31, 2024 and 2023. 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. In the event that changes in an estimate for a closure and post-closure liability are associated with a significant change in facts and circumstances at a landfill or a non-operating section of a landfill, corresponding adjustments to recorded liabilities and Impairments and other operating items are made as soon as is practical. 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 one The following is a reconciliation of the Company’s final capping, closure and post-closure liability balance from December 31, 2022 to December 31, 2024: ​ ​ ​ ​ ​ Final capping, closure and post-closure liability at December 31, 2022 $ 344,606 Liability adjustments ​ 189,136 Accretion expense associated with landfill obligations ​ 19,418 Closure payments ​ (39,429) Assumption of closure liabilities from acquisitions ​ 7,687 Foreign currency translation adjustment ​ ​ 815 Final capping, closure and post-closure liability at December 31, 2023 ​ 522,233 Liability adjustments ​ 497,955 Accretion expense associated with landfill obligations ​ 29,373 Closure payments ​ (247,552) Assumption of closure liabilities from acquisitions ​ ​ 60,913 Foreign currency translation adjustment ​ (2,799) Final capping, closure and post-closure liability at December 31, 2024 ​ $ 860,123 ​ Liability adjustments of $497,955 and $189,136 for the years ended December 31, 2024 and 2023, 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. In the event that changes in an estimate for a closure and post-closure liability are associated with a significant change in facts and circumstances at a landfill or a non-operating section of a landfill, corresponding adjustments to recorded liabilities and Impairments and other operating items are made as soon as is practical. In 2023, the Company recorded an additional $159,547 of charges to adjust the carrying value of a closure and post-closure liability at an area of a landfill site that has been deemed to reach final capacity. Furthermore, during the quarter ended December 31, 2024, the Company recorded an additional $480,786 of charges to adjust the carrying value of the closure and post-closure liability at the same landfill, which ceased active waste disposal operations as of December 31, 2024. See “Final capping, closure and post-closure obligations” within this Note 3 for additional information regarding the Company’s accounting for landfills. - 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 4 to 51 years). The Company uses an accelerated or straight line basis for amortization, depending on the attributes of the related intangibles.
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. 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. The Company’s reporting units consisted of its six geographic solid waste operating segments at December 31, 2024, 2023 and 2022. 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 six geographic operating segments at December 31, 2024, 2023 and 2022 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 2024 discounted cash flow analyses were based on ten-year financial forecasts, which in turn were based on the 2025 annual budget developed internally by management. These forecasts reflect operating profit margins that were consistent with 2024 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 8.5%. 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 six geographic operating segments as a result of its annual goodwill and indefinite-lived intangible impairment tests for the years ended December 31, 2024, 2023 or 2022.
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 quarter ended December 31, 2024, the Company made the decision to cease active waste disposal operations as of December 31, 2024 at the Chiquita Canyon Landfill, and therefore recorded a charge of $116,090 to Impairments and other operating items in the Consolidated Statement of Net Income, which reduced the carrying value of property and equipment. During the years ended December 31, 2023 and 2022, the Company did not record any significant impairment charges for finite-lived intangible assets or property and equipment. 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, 2024 ​ December 31, 2023 ​ ​ Restricted ​ Restricted ​ Restricted ​ Restricted ​ Cash Investments Cash Investments Settlement of insurance claims ​ $ 121,751 ​ $ — ​ $ 83,270 ​ $ — Landfill closure and post-closure obligations ​ ​ 8,852 ​ ​ 77,855 ​ ​ 13,546 ​ ​ 68,266 Other financial assurance requirements ​ ​ 5,204 ​ ​ 271 ​ ​ 8,823 ​ ​ 2,084 ​ ​ $ 135,807 ​ $ 78,126 ​ $ 105,639 ​ $ 70,350 ​ 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, 2024 and 2023, 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, 2024 and 2023, 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, 2024 and 2023, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Carrying Value at ​ Fair Value (a) at ​ ​ December 31, ​ December 31, ​ December 31, ​ December 31, ​ 2024 2023 2024 2023 4.25% Senior Notes due 2028 ​ $ 500,000 ​ $ 500,000 ​ $ 488,500 ​ $ 496,800 3.50% Senior Notes due 2029 ​ $ 500,000 ​ $ 500,000 ​ $ 471,450 ​ $ 478,350 4.50% Senior Notes due 2029 ​ $ 347,500 ​ $ — ​ $ 359,168 ​ $ — 2.60% Senior Notes due 2030 ​ $ 600,000 ​ $ 600,000 ​ $ 536,220 ​ $ 539,460 2.20% Senior Notes due 2032 ​ $ 650,000 ​ $ 650,000 ​ $ 535,275 ​ $ 543,725 3.20% Senior Notes due 2032 ​ $ 500,000 ​ $ 500,000 ​ $ 437,150 ​ $ 450,200 4.20% Senior Notes due 2033 ​ $ 750,000 ​ $ 750,000 ​ $ 696,300 ​ $ 729,600 5.00% Senior Notes due 2034 ​ $ 750,000 ​ $ — ​ $ 731,625 ​ $ — 3.05% Senior Notes due 2050 ​ $ 500,000 ​ $ 500,000 ​ $ 321,700 ​ $ 362,600 2.95% Senior Notes due 2052 ​ $ 850,000 ​ $ 850,000 ​ $ 528,955 ​ $ 601,460 (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. 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 Revolving 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, 2024 were specifically designated to the Revolving Credit Agreement and accounted for as cash flow hedges. At December 31, 2024, the Company’s derivative instruments included four interest rate swap agreements as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fixed Variable ​ ​ ​ ​ Notional ​ Interest ​ Interest Rate ​ ​ ​ Expiration Date Entered ​ Amount ​ Rate Paid (a) ​ Received ​ Effective Date (b) ​ Date August 2017 ​ $ 200,000 2.1230 % 1-month Term SOFR November 2022 October 2025 June 2018 ​ $ 200,000 ​ 2.8480 % 1-month Term SOFR ​ November 2022 ​ October 2025 June 2018 ​ $ 200,000 ​ 2.8284 % 1-month Term SOFR ​ November 2022 ​ October 2025 December 2018 ​ $ 200,000 ​ 2.7715 % 1-month Term SOFR ​ November 2022 ​ July 2027 (a) Plus applicable margin. (b) In October 2022, the Company amended the reference rate in all of its outstanding interest rate swap contracts to replace One-Month LIBOR with One-Month Term SOFR and certain credit spread adjustments. The Company did not record any gains or losses upon the conversion of the reference rates in these interest rate swap contracts, and the Company believes these amendments will not have a material impact on its Consolidated Financial Statements. The fair values of derivative instruments designated as cash flow hedges at December 31, 2024, 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 (a) ​ $ 10,545 Accrued liabilities ​ $ — ​ Other assets, net ​ 3,384 ​ ​ ​ ​ Total derivatives designated as cash flow hedges ​ ​ ​ $ 13,929 ​ ​ ​ $ — (a) Represents the estimated amount of the existing unrealized gains on interest rate swaps as of December 31, 2024 (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, 2023, 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 ​ $ 15,842 Accrued liabilities ​ $ — ​ Other assets, net ​ 6,945 ​ ​ ​ Total derivatives designated as cash flow hedges ​ ​ ​ $ 22,787 ​ ​ ​ $ — ​ 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, 2024, 2023 and 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 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, ​ 2024 2023 2022 ​ 2024 2023 2022 Interest rate swaps ​ $ 8,531 ​ $ 7,782 ​ $ 56,107 ​ Interest expense ​ $ (15,043) ​ $ (14,411) ​ $ 4,815 (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, 2024, 2023 and 2022, was $77,885 ($58,203 net of taxes), $70,436 ($52,708 net of taxes) and $63,485 ($47,503 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, 2024, related to unvested RSU awards was $83,706 and this future expense will be recognized over the remaining vesting period of the RSU awards, which extends to 2028. The weighted average remaining vesting period of the RSU awards is 1.2 years. The total unrecognized compensation cost at December 31, 2024, related to unvested PSU awards was $14,877 and this future expense will be recognized over the remaining vesting period of the PSU awards, which extends to 2027. The weighted average remaining vesting period of PSU awards is 1.1 years. Other Share-Based Awards As of December 31, 2024, 2023 and 2022, the Company had a liability of $8,068, $8,060 and $8,042, respectively, representing the December 31, 2024, 2023 and 2022 fair values, respectively, of outstanding Progressive Waste restricted share units which are expected to be cash settled. All remaining unvested Progressive Waste restricted share units vested during the year ended December 31, 2019.
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, 2024, 2023 and 2022, was $9,197, $9,097 and $8,335, 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, 2024 and 2023, the Company’s total accrual for self-insured liabilities was $243,764 and $183,546, respectively, which is included in Accrued liabilities in the Consolidated Balance Sheets. For the years ended December 31, 2024, 2023 and 2022, the Company recognized $323,760, $261,589 and $204,347, 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, 2024
LEASES.
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, 2024, 2023 and 2022. 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, 2024, 2023 and 2022. 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, 2024
Organization And Summary Of Significant Accounting Policies [Line Items]
Total Reported Revenues by Service Line	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2024 2023 2022 Commercial $ 2,670,549 ​ $ 2,476,891 $ 2,176,295 Residential ​ 2,258,911 ​ ​ 2,125,068 ​ ​ 1,891,108 Industrial and construction roll off ​ 1,403,313 ​ ​ 1,333,020 ​ ​ 1,183,624 Total collection ​ 6,332,773 ​ ​ 5,934,979 ​ ​ 5,251,027 Landfill ​ 1,557,872 ​ ​ 1,483,397 ​ ​ 1,328,942 Transfer ​ 1,349,080 ​ ​ 1,198,385 ​ ​ 1,026,050 Recycling ​ 241,873 ​ ​ 147,039 ​ ​ 204,876 E&P ​ 521,504 ​ ​ 232,211 ​ ​ 210,562 Intermodal and other ​ 191,887 ​ ​ 171,721 ​ ​ 188,471 Intercompany ​ (1,275,398) ​ ​ (1,145,781) ​ ​ (998,069) Total $ 8,919,591 ​ $ 8,021,951 $ 7,211,859
Allowance for Credit Loss	The following is a rollforward of the Company’s allowance for credit losses for the periods indicated: ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2024 2023 Beginning balance ​ $ 23,553 ​ $ 22,939 Current period provision for expected credit losses ​ ​ 20,243 ​ ​ 17,430 Write-offs charged against the allowance ​ ​ (23,141) ​ ​ (22,743) Recoveries collected ​ ​ 5,255 ​ ​ 5,853 Impact of changes in foreign currency ​ ​ (180) ​ ​ 74 Ending balance ​ $ 25,730 ​ $ 23,553
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 5 – 12 years
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, 2022 to December 31, 2024: ​ ​ ​ ​ ​ Final capping, closure and post-closure liability at December 31, 2022 $ 344,606 Liability adjustments ​ 189,136 Accretion expense associated with landfill obligations ​ 19,418 Closure payments ​ (39,429) Assumption of closure liabilities from acquisitions ​ 7,687 Foreign currency translation adjustment ​ ​ 815 Final capping, closure and post-closure liability at December 31, 2023 ​ 522,233 Liability adjustments ​ 497,955 Accretion expense associated with landfill obligations ​ 29,373 Closure payments ​ (247,552) Assumption of closure liabilities from acquisitions ​ ​ 60,913 Foreign currency translation adjustment ​ (2,799) Final capping, closure and post-closure liability at December 31, 2024 ​ $ 860,123
Restricted Cash and Restricted Investments	Restricted cash and restricted investments consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2024 ​ December 31, 2023 ​ ​ Restricted ​ Restricted ​ Restricted ​ Restricted ​ Cash Investments Cash Investments Settlement of insurance claims ​ $ 121,751 ​ $ — ​ $ 83,270 ​ $ — Landfill closure and post-closure obligations ​ ​ 8,852 ​ ​ 77,855 ​ ​ 13,546 ​ ​ 68,266 Other financial assurance requirements ​ ​ 5,204 ​ ​ 271 ​ ​ 8,823 ​ ​ 2,084 ​ ​ $ 135,807 ​ $ 78,126 ​ $ 105,639 ​ $ 70,350
Carrying Values and Fair Values of Debt Instruments	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Carrying Value at ​ Fair Value (a) at ​ ​ December 31, ​ December 31, ​ December 31, ​ December 31, ​ 2024 2023 2024 2023 4.25% Senior Notes due 2028 ​ $ 500,000 ​ $ 500,000 ​ $ 488,500 ​ $ 496,800 3.50% Senior Notes due 2029 ​ $ 500,000 ​ $ 500,000 ​ $ 471,450 ​ $ 478,350 4.50% Senior Notes due 2029 ​ $ 347,500 ​ $ — ​ $ 359,168 ​ $ — 2.60% Senior Notes due 2030 ​ $ 600,000 ​ $ 600,000 ​ $ 536,220 ​ $ 539,460 2.20% Senior Notes due 2032 ​ $ 650,000 ​ $ 650,000 ​ $ 535,275 ​ $ 543,725 3.20% Senior Notes due 2032 ​ $ 500,000 ​ $ 500,000 ​ $ 437,150 ​ $ 450,200 4.20% Senior Notes due 2033 ​ $ 750,000 ​ $ 750,000 ​ $ 696,300 ​ $ 729,600 5.00% Senior Notes due 2034 ​ $ 750,000 ​ $ — ​ $ 731,625 ​ $ — 3.05% Senior Notes due 2050 ​ $ 500,000 ​ $ 500,000 ​ $ 321,700 ​ $ 362,600 2.95% Senior Notes due 2052 ​ $ 850,000 ​ $ 850,000 ​ $ 528,955 ​ $ 601,460 (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.
Fair Value of Derivative Instrument Designated as Cash Flow Hedges	The fair values of derivative instruments designated as cash flow hedges at December 31, 2024, 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 (a) ​ $ 10,545 Accrued liabilities ​ $ — ​ Other assets, net ​ 3,384 ​ ​ ​ ​ Total derivatives designated as cash flow hedges ​ ​ ​ $ 13,929 ​ ​ ​ $ — (a) Represents the estimated amount of the existing unrealized gains on interest rate swaps as of December 31, 2024 (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, 2023, 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 ​ $ 15,842 Accrued liabilities ​ $ — ​ Other assets, net ​ 6,945 ​ ​ ​ Total derivatives designated as cash flow hedges ​ ​ ​ $ 22,787 ​ ​ ​ $ —
Impact of Cash Flow Hedges on Results of Operations, Comprehensive Income (Loss) and Accumulated Other Comprehensive Income (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, 2024, 2023 and 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 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, ​ 2024 2023 2022 ​ 2024 2023 2022 Interest rate swaps ​ $ 8,531 ​ $ 7,782 ​ $ 56,107 ​ Interest expense ​ $ (15,043) ​ $ (14,411) ​ $ 4,815 (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
Organization And Summary Of Significant Accounting Policies [Line Items]
Company's Derivative Instruments	At December 31, 2024, the Company’s derivative instruments included four interest rate swap agreements as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fixed Variable ​ ​ ​ ​ Notional ​ Interest ​ Interest Rate ​ ​ ​ Expiration Date Entered ​ Amount ​ Rate Paid (a) ​ Received ​ Effective Date (b) ​ Date August 2017 ​ $ 200,000 2.1230 % 1-month Term SOFR November 2022 October 2025 June 2018 ​ $ 200,000 ​ 2.8480 % 1-month Term SOFR ​ November 2022 ​ October 2025 June 2018 ​ $ 200,000 ​ 2.8284 % 1-month Term SOFR ​ November 2022 ​ October 2025 December 2018 ​ $ 200,000 ​ 2.7715 % 1-month Term SOFR ​ November 2022 ​ July 2027 (a) Plus applicable margin. (b) In October 2022, the Company amended the reference rate in all of its outstanding interest rate swap contracts to replace One-Month LIBOR with One-Month Term SOFR and certain credit spread adjustments. The Company did not record any gains or losses upon the conversion of the reference rates in these interest rate swap contracts, and the Company believes these amendments will not have a material impact on its Consolidated Financial Statements.

Prepaid Expenses and Other Cu_2

Prepaid Expenses and Other Current Assets (Tables)	12 Months Ended
	Dec. 31, 2024
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, ​ 2024 2023 Income taxes receivable $ 37,599 $ 28,124 Parts and supplies ​ ​ 71,156 ​ ​ 61,673 Prepaid insurance ​ ​ 40,014 ​ ​ 26,607 Unrealized cash flow hedge gains ​ ​ 10,545 ​ ​ 15,842 Prepaid licenses and permits ​ ​ 14,141 ​ ​ 13,898 Other ​ ​ 56,064 ​ ​ 60,289 ​ $ 229,519 $ 206,433 ​

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	12 Months Ended
	Dec. 31, 2024
PROPERTY AND EQUIPMENT, NET
Property and Equipment, Net	Property and equipment, net consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2024 2023 Landfill site costs ​ $ 5,778,483 ​ $ 5,507,596 Rolling stock ​ 3,428,765 ​ 3,084,623 Land, buildings and improvements ​ 2,328,287 ​ 1,807,719 Containers ​ 1,364,624 ​ 1,277,594 Machinery and equipment ​ 1,539,394 ​ 1,222,792 Construction in progress ​ 191,404 ​ 167,025 ​ ​ 14,630,957 ​ 13,067,349 Less accumulated depreciation and depletion ​ (6,595,028) ​ (5,839,018) ​ ​ $ 8,035,929 ​ $ 7,228,331

LEASES (Tables)

LEASES (Tables)	12 Months Ended
	Dec. 31, 2024
LEASES.
Summary of lease cost for operating and finance leases	Lease cost for operating and finance leases for the years ended December 31, 2024, 2023 and 2022 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2024 ​ 2023 ​ 2022 Operating lease cost $ 53,329 ​ $ 47,840 ​ $ 41,891 Finance lease cost: ​ ​ ​ ​ ​ ​ ​ ​ Amortization of leased assets ​ 3,375 ​ ​ 2,852 ​ ​ 2,484 Interest on leased liabilities ​ 273 ​ ​ 228 ​ ​ 219 Total lease cost $ 56,977 ​ $ 50,920 ​ $ 44,594 ​ Supplemental cash flow information and non-cash activity related to the Company’s leases are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2024 ​ ​ 2023 ​ ​ 2022 Cash paid for amounts included in the measurement of lease liabilities: ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating cash flows from operating leases ​ $ 50,837 ​ $ 46,688 ​ $ 40,782 Operating cash flows from finance leases ​ $ 273 ​ $ 228 ​ $ 219 Financing cash flows from finance leases ​ $ 3,356 ​ $ 2,817 ​ $ 2,427 Non-cash activity: ​ ​ ​ ​ ​ ​ ​ ​ ​ Right-of-use assets obtained in exchange for lease liabilities - operating leases ​ $ 62,922 ​ $ 92,503 ​ $ 63,648 Right-of-use assets obtained in exchange for lease liabilities - finance leases ​ $ 2,569 ​ $ 1,388 ​ $ 3,369 ​ Weighted-average remaining lease term and discount rate for the Company’s leases are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2024 ​ 2023 ​ 2022 Weighted average remaining lease term - operating leases ​ 9.7 years 10.9 years 8.9 years Weighted average remaining lease term - finance leases ​ 2.8 years ​ 3.4 years ​ 4.2 years Weighted average discount rate - operating leases ​ 4.34 % 4.04 % 2.93 % Weighted average discount rate - finance leases ​ 2.99 % ​ 2.36 % ​ 1.96 %
Summary of future minimum lease payments, operating leases	As of December 31, 2024, future minimum lease payments, reconciled to the respective lease liabilities, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating Leases ​ ​ Finance Leases 2025 $ 53,080 ​ $ 3,870 2026 ​ 50,343 ​ 3,284 2027 ​ 46,834 ​ 1,858 2028 ​ 39,682 ​ 540 2029 ​ 32,950 ​ 126 Thereafter ​ 170,462 ​ — Minimum lease payments ​ 393,351 ​ 9,678 Less: imputed interest ​ (80,754) ​ ​ (431) Present value of minimum lease payments ​ ​ 312,597 ​ ​ 9,247 Less: current portion of lease liabilities ​ ​ (40,490) ​ ​ (3,631) Long-term portion of lease liabilities ​ $ 272,107 ​ $ 5,616
Summary of future minimum lease payments, finance leases	As of December 31, 2024, future minimum lease payments, reconciled to the respective lease liabilities, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating Leases ​ ​ Finance Leases 2025 $ 53,080 ​ $ 3,870 2026 ​ 50,343 ​ 3,284 2027 ​ 46,834 ​ 1,858 2028 ​ 39,682 ​ 540 2029 ​ 32,950 ​ 126 Thereafter ​ 170,462 ​ — Minimum lease payments ​ 393,351 ​ 9,678 Less: imputed interest ​ (80,754) ​ ​ (431) Present value of minimum lease payments ​ ​ 312,597 ​ ​ 9,247 Less: current portion of lease liabilities ​ ​ (40,490) ​ ​ (3,631) Long-term portion of lease liabilities ​ $ 272,107 ​ $ 5,616

ACQUISITIONS (Tables)

ACQUISITIONS (Tables)	12 Months Ended
	Dec. 31, 2024
ACQUISITIONS
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, 2024, 2023 and 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2024 2023 2022 ​ ​ Acquisitions ​ Acquisitions ​ Acquisitions Fair value of consideration transferred: ​ ​ ​ Cash ​ $ 2,120,878 ​ $ 676,793 ​ $ 2,206,901 Debt assumed ​ 77,766 ​ 76,001 ​ 127,136 ​ ​ 2,198,644 ​ 752,794 ​ 2,334,037 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired: ​ ​ ​ ​ ​ Accounts receivable ​ 100,995 ​ ​ 18,006 ​ 49,696 Prepaid expenses and other current assets ​ 13,513 ​ ​ 5,025 ​ 9,428 Restricted investments ​ ​ — ​ ​ 5,462 ​ ​ 7,469 Operating lease right-of-use assets ​ ​ 24,700 ​ ​ 15,364 ​ ​ 4,707 Property and equipment ​ 913,729 ​ ​ 207,164 ​ 1,073,155 Long-term franchise agreements and contracts ​ 159,028 ​ ​ 76,401 ​ 239,866 Customer lists ​ 214,459 ​ ​ 19,719 ​ 74,940 Permits and other intangibles ​ ​ 224,728 ​ ​ 3,050 ​ ​ 187,107 Other assets ​ 1,671 ​ ​ 24 ​ 243 Accounts payable and accrued liabilities ​ (27,902) ​ ​ (14,596) ​ (56,633) Current portion of operating lease liabilities ​ ​ (2,875) ​ ​ (712) ​ ​ (1,546) Deferred revenue ​ (12,148) ​ ​ (3,443) ​ (10,761) Contingent consideration ​ (28,885) ​ ​ (13,450) ​ (6,642) Long-term portion of operating lease liabilities ​ ​ (14,774) ​ ​ (14,652) ​ ​ (3,161) Other long-term liabilities ​ (67,109) ​ ​ (10,277) ​ (6,915) Deferred income taxes ​ — ​ ​ (3,212) ​ (51,507) Total identifiable net assets ​ 1,499,130 ​ 289,873 ​ 1,509,446 Goodwill ​ $ 699,514 ​ $ 462,921 ​ $ 824,591

INTANGIBLE ASSETS, NET (Tables)

INTANGIBLE ASSETS, NET (Tables)	12 Months Ended
	Dec. 31, 2024
INTANGIBLE ASSETS, NET
Intangible Assets Exclusive of Goodwill	Intangible assets, exclusive of goodwill, consisted of the following at December 31, 2024: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ ​ Accumulated Net ​ ​ Carrying ​ Accumulated ​ Impairment ​ Carrying ​ ​ Amount ​ Amortization ​ Loss ​ Amount Finite-lived intangible assets: ​ ​ ​ ​ Long-term franchise agreements and contracts ​ $ 1,104,585 ​ $ (400,674) ​ $ — ​ $ 703,911 Customer lists ​ 1,005,355 ​ (693,594) ​ — ​ 311,761 Permits and other ​ 999,357 ​ (164,239) ​ (40,784) ​ 794,334 ​ ​ 3,109,297 ​ (1,258,507) ​ (40,784) ​ 1,810,006 Indefinite-lived intangible assets: ​ ​ ​ ​ Solid waste collection and transportation permits ​ 181,613 ​ — ​ — ​ 181,613 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Intangible assets, exclusive of goodwill ​ $ 3,290,910 ​ $ (1,258,507) ​ $ (40,784) ​ $ 1,991,619 Intangible assets, exclusive of goodwill, consisted of the following at December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ ​ Accumulated Net ​ ​ Carrying ​ Accumulated ​ Impairment ​ Carrying ​ ​ Amount ​ Amortization ​ Loss ​ Amount Finite-lived intangible assets: ​ ​ ​ ​ Long-term franchise agreements and contracts ​ $ 960,033 ​ $ (343,099) ​ $ — ​ $ 616,934 Customer lists ​ 806,257 ​ (606,192) ​ — ​ 200,065 Permits and other ​ 784,905 ​ (139,192) ​ (40,784) ​ 604,929 ​ ​ 2,551,195 ​ (1,088,483) ​ (40,784) ​ 1,421,928 Indefinite-lived intangible assets: ​ ​ ​ ​ Solid waste collection and transportation permits ​ 181,613 ​ — ​ — ​ 181,613 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Intangible assets, exclusive of goodwill ​ $ 2,732,808 ​ $ (1,088,483) ​ $ (40,784) ​ $ 1,603,541
Estimated Future Amortization Expense of Amortizable Intangible Assets	Estimated future amortization expense for the next five years relating to finite-lived intangible assets owned as of December 31, 2024 is as follows: ​ ​ ​ ​ ​ For the year ending December 31, 2025 $ 180,792 For the year ending December 31, 2026 ​ $ 157,827 For the year ending December 31, 2027 ​ $ 137,790 For the year ending December 31, 2028 ​ $ 122,230 For the year ending December 31, 2029 ​ $ 110,584 ​

ACCRUED LIABILITIES (Tables)

ACCRUED LIABILITIES (Tables)	12 Months Ended
	Dec. 31, 2024
ACCRUED LIABILITIES
Accrued liabilities	Accrued liabilities consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2024 2023 Insurance claims and premiums ​ $ 244,536 ​ $ 184,403 Final capping, closure and post-closure liability ​ ​ 199,736 ​ ​ 92,946 Payroll and payroll-related ​ 127,518 ​ 108,423 Interest payable ​ 68,455 ​ 52,726 Property taxes ​ ​ 17,548 ​ ​ 15,545 Environmental remediation reserves ​ 8,808 ​ 10,860 Cell processing reserves ​ 2,148 ​ 3,246 Transaction-related expenses ​ ​ 1,471 ​ ​ 958 Other ​ 66,604 ​ 52,321 ​ ​ $ 736,824 ​ $ 521,428 ​

Long-Term Debt (Tables)

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2024
Long-Term Debt [Abstract]
Long-Term Debt	The following table presents the Company’s long-term debt as of December 31, 2024 and 2023: ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2024 2023 Revolving Credit Agreement, bearing interest ranging from 4.59% to 7.50% (a) $ 2,164,325 ​ $ — Revolver under 2021 Revolving and Term Credit Agreement, bearing interest ranging from 6.40% to 8.50% (b) ​ — ​ ​ 453,245 Term loan under 2021 Revolving and Term Credit Agreement, bearing interest at 6.50% (b) — ​ ​ 650,000 Term loan under 2022 Term Loan Agreement, bearing interest at 6.44% (b), (c) ​ — ​ ​ 800,000 4.25% Senior Notes due 2028 ​ 500,000 ​ ​ 500,000 3.50% Senior Notes due 2029 ​ 500,000 ​ ​ 500,000 4.50% Senior Notes due 2029 ​ 347,500 ​ ​ — 2.60% Senior Notes due 2030 ​ 600,000 ​ ​ 600,000 2.20% Senior Notes due 2032 ​ 650,000 ​ ​ 650,000 3.20% Senior Notes due 2032 ​ 500,000 ​ ​ 500,000 4.20% Senior Notes due 2033 ​ 750,000 ​ ​ 750,000 5.00% Senior Notes due 2034 ​ 750,000 ​ ​ — 3.05% Senior Notes due 2050 ​ 500,000 ​ ​ 500,000 2.95% Senior Notes due 2052 ​ 850,000 ​ ​ 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 2044 (a) 30,641 ​ ​ 48,774 Finance leases, bearing interest ranging from 1.89% to 5.07%, with lease expiration dates ranging from 2026 to 2029 (a) ​ 9,247 ​ ​ 10,034 ​ 8,151,713 ​ 6,812,053 Less – current portion (7,851) ​ ​ (26,462) Less – unamortized debt discount and issuance costs (70,934) ​ ​ (60,820) Long-term portion of debt and notes payable $ 8,072,928 ​ $ 6,724,771 (a) Interest rates represent the interest rates incurred at December 31, 2024. (b) Interest rates represent the interest rates incurred at December 31, 2023. (c) Interest rate margin for term loan under 2022 Term Loan Agreement was 1.00% at December 31, 2023.
Details of the Company's Credit Agreement	Details of the Revolving Credit Agreement at December 31, 2024 and details of the 2021 Revolving and Term Credit Agreement (as defined below) at December 31, 2023 are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2024 2023 Revolver ​ ​ ​ Available $ 778,374 ​ $ 1,357,013 ​ Letters of credit outstanding $ 57,301 ​ $ 39,742 ​ Total amount drawn, as follows: $ 2,164,325 ​ $ 453,245 ​ Amount drawn – U.S. Term SOFR rate loan $ 800,000 ​ $ 90,000 ​ Interest rate applicable – U.S. Term SOFR rate loan ​ 5.65 % ​ 6.46 % Interest rate margin – U.S. Term SOFR rate loan ​ 1.00 % ​ 1.00 % Amount drawn – U.S. Term SOFR rate loan $ 500,000 ​ $ 150,000 ​ Interest rate applicable – U.S. Term SOFR rate loan ​ 5.69 % ​ 6.50 % Interest rate margin – U.S. Term SOFR rate loan ​ 1.00 % ​ 1.00 % Amount drawn – U.S. Term SOFR rate loan $ 50,000 ​ $ — ​ Interest rate applicable – U.S. Term SOFR rate loan ​ 5.46 % ​ — % Interest rate margin – U.S. Term SOFR rate loan ​ 1.00 % ​ — % Amount drawn – U.S. base rate loan $ 95,000 ​ $ 28,000 ​ Interest rate applicable – U.S. base rate loan ​ 7.50 % ​ 8.50 % Interest rate margin – U.S. base rate loan ​ — % ​ — % Amount drawn – Canadian Term CORRA loan $ 590,750 ​ $ — ​ Interest rate applicable - Canadian term CORRA loan ​ 5.24 % ​ — % Interest rate margin – Canadian term CORRA loan ​ 1.00 % ​ — % Amount drawn – Canadian Term CORRA loan $ 86,875 ​ $ — ​ Interest rate applicable - Canadian term CORRA loan ​ 4.59 % ​ — % Interest rate margin – Canadian term CORRA loan ​ 1.00 % ​ — % Amount drawn – Canadian prime rate loan $ 41,700 ​ $ 15,122 ​ Interest rate applicable - Canadian prime rate loan 5.45 % 7.20 % Interest rate margin – Canadian prime rate loan — % — % Amount drawn – Canadian bankers’ acceptance $ — ​ $ 153,111 ​ Interest rate applicable – Canadian bankers’ acceptance — % 6.46 % Interest rate acceptance fee – Canadian bankers’ acceptance — % 1.00 % Amount drawn – Canadian bankers’ acceptance $ — ​ $ 17,012 ​ Interest rate applicable – Canadian bankers’ acceptance ​ — % ​ 6.40 % Interest rate acceptance fee – Canadian bankers’ acceptance ​ — % ​ 1.00 % Commitment – rate applicable 0.09 % 0.09 % Term loan ​ ​ ​ ​ Amount drawn – U.S. Term SOFR rate loan $ — ​ $ 650,000 ​ Interest rate applicable – U.S. Term SOFR rate loan ​ — % ​ 6.50 % Interest rate margin – U.S. Term SOFR rate loan ​ — % ​ 1.00 %
Aggregate Contractual Future Principal Payments by Calendar Year on Long-Term Debt	As of December 31, 2024, aggregate contractual future principal payments by calendar year on long-term debt are due as follows: ​ ​ ​ ​ ​ 2025 $ 7,851 2026 ​ 7,249 2027 ​ 6,030 2028 ​ 504,864 2029 ​ 3,016,290 Thereafter ​ 4,609,429 ​ ​ $ 8,151,713 ​

FAIR VALUE OF FINANCIAL INSTR_2

FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)	12 Months Ended
	Dec. 31, 2024
FAIR VALUE OF FINANCIAL INSTRUMENTS
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, 2024 and 2023, were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurement at December 31, 2024 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 asset position ​ $ 13,929 ​ $ — ​ $ 13,929 ​ $ — Restricted cash ​ $ 135,807 ​ $ 135,807 ​ $ — ​ $ — Restricted investments ​ $ 77,900 ​ $ — ​ $ 77,900 ​ $ — Contingent consideration ​ $ (87,162) ​ $ — ​ $ — ​ $ (87,162) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurement at December 31, 2023 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 asset position ​ $ 22,787 ​ $ — ​ $ 22,787 ​ $ — Restricted cash ​ $ 105,639 ​ $ 105,639 ​ $ — ​ $ — Restricted investments ​ $ 70,658 ​ $ — ​ $ 70,658 ​ $ — Contingent consideration ​ $ (115,030) ​ $ — ​ $ — ​ $ (115,030)
Fair Value for Level 3 Liabilities	The following table summarizes the changes in the fair value for Level 3 liabilities related to contingent consideration for the years ended December 31, 2024 and 2023: ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2024 2023 Beginning balance $ 115,030 ​ $ 81,415 Contingent consideration recorded at acquisition date 28,885 ​ 13,450 Payment of contingent consideration recorded at acquisition date (27,743) ​ (13,317) Payment of contingent consideration recorded in earnings (35,035) ​ — Adjustments to contingent consideration ​ (3) ​ ​ 30,367 Interest accretion expense 6,217 ​ 3,115 Foreign currency translation adjustment (189) ​ — Ending balance $ 87,162 ​ $ 115,030 ​

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Tables)	12 Months Ended
	Dec. 31, 2024
COMMITMENTS AND CONTINGENCIES.
Future Minimum Purchase Commitments	As of December 31, 2024, future minimum purchase commitments, by calendar year, are as follows: ​ ​ ​ ​ ​ 2025 $ 140,123 2026 ​ 37,284 2027 ​ ​ 778 2028 ​ ​ 621 2029 ​ ​ 466 Thereafter ​ ​ — ​ ​ $ 179,272

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2024
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Common Stock Shares Reserved for Issuance	​ ​ ​ ​ For outstanding RSUs, PSUs and warrants 2,083,109 For future grants under the 2016 Incentive Award Plan 1,993,310 For future grants under the Employee Share Purchase Plan ​ 903,541 ​ 4,979,960
Restricted Stock Units Activity	A summary of the Company’s RSU activity is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2024 2023 2022 Weighted average grant-date fair value of restricted share units granted ​ $ 164.93 ​ $ 133.65 ​ $ 121.26 Total fair value of restricted share units vested ​ $ 39,745 ​ $ 39,754 ​ $ 28,751
Summary of Warrant Activity	A summary of warrant activity during the year ended December 31, 2024, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ Warrants ​ Exercise Price Outstanding at December 31, 2023 817,873 ​ $ 127.85 Granted 301,719 ​ $ 171.51 Forfeited (153,306) ​ $ 133.59 Exercised (44,860) ​ $ 107.04 Outstanding at December 31, 2024 921,426 ​ $ 142.21
Summarized Information about Warrants Outstanding	The following table summarizes information about warrants outstanding as of December 31, 2024 and 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value of ​ ​ ​ ​ ​ ​ Warrants ​ ​ ​ Warrants ​ Outstanding at December 31, Grant Date ​ Issued ​ Exercise Price ​ Issued ​ 2024 ​ 2023 Throughout 2019 ​ 151,008 ​ $74.25 to $95.61 ​ $ 2,634 ​ — ​ 25,490 Throughout 2020 ​ 164,890 ​ $72.65 to $104.89 ​ $ 3,140 ​ 85,293 ​ 145,586 Throughout 2021 ​ 218,166 ​ $99.33 to $135.97 ​ $ 5,584 ​ 191,155 ​ 191,155 Throughout 2022 ​ 380,478 ​ $125.32 to $143.95 ​ $ 12,972 ​ 289,276 ​ 326,085 Throughout 2023 ​ 129,557 ​ $129.75 to $142.93 ​ $ 5,133 ​ 106,649 ​ 129,557 Throughout 2024 ​ 301,719 ​ $149.27 to $192.47 ​ $ 14,651 ​ 249,053 ​ — ​ ​ ​ ​ ​ ​ ​ 921,426 817,873
Restricted stock units (RSUs)
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Summary of Activity Related to Restricted Share Units	A summary of activity related to RSUs during the year ended December 31, 2024, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ Grant Date Fair ​ Unvested Shares ​ Value Per Share Outstanding at December 31, 2023 936,267 ​ $ 120.97 Granted 371,343 ​ $ 164.93 Forfeited (51,520) ​ $ 138.91 Vested and issued (343,530) ​ $ 115.69 Outstanding at December 31, 2024 912,560 ​ $ 139.83
Performance shares
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, ​ 2024 2023 2022 Weighted average grant-date fair value of PSUs granted ​ $ 138.29 ​ $ 133.83 ​ $ 117.94 Total fair value of PSUs vested ​ $ 14,948 ​ $ 20,196 ​ $ 4,674
Summary of Performance-Based Restricted Share Units Activity and Related Information	A summary of activity related to PSUs during the year ended December 31, 2024, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ Grant Date Fair ​ Unvested Shares ​ Value Per Share Outstanding at December 31, 2023 259,532 ​ $ 113.68 Granted 113,166 ​ $ 138.29 Vested and issued (153,555) ​ $ 97.35 Outstanding at December 31, 2024 219,143 ​ $ 137.83
Deferred share units
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, ​ 2024 ​ 2023 2022 Weighted average grant-date fair value of DSUs granted ​ $ 168.71 ​ $ 136.47 ​ $ 121.00 Total fair value of DSUs awarded ​ $ 632 ​ $ 538 ​ $ 253
Summary of Activity Related to Restricted Share Units	A summary of activity related to DSUs during the year ended December 31, 2024, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ Grant Date Fair ​ Vested Shares ​ Value Per Share Outstanding at December 31, 2023 30,481 ​ $ 77.34 Granted 3,746 ​ $ 168.71 Cash settled (9,207) ​ $ 61.65 Share settled (4,602) ​ $ 94.15 Outstanding at December 31, 2024 20,418 ​ $ 97.38
Progressive Waste Solutions Ltd. | Restricted stock units (RSUs)
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Summary of Activity Related to Restricted Share Units	​ ​ ​ ​ Outstanding at December 31, 2023 51,812 Cash settled (6,346) Outstanding at December 31, 2024 45,466

Other Comprehensive Income (L_2

Other Comprehensive Income (Loss) (Tables)	12 Months Ended
	Dec. 31, 2024
Other Comprehensive Income (Loss) [Abstract]
Components of Other Comprehensive Income (Loss)	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2024 ​ Gross Tax Effect Net of Tax Interest rate swap amounts reclassified into interest expense ​ $ (20,467) ​ $ 5,424 ​ $ (15,043) Changes in fair value of interest rate swaps ​ 11,607 ​ (3,076) ​ 8,531 Foreign currency translation adjustment ​ (189,402) ​ — ​ (189,402) ​ ​ $ (198,262) ​ $ 2,348 ​ $ (195,914) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2023 ​ Gross Tax Effect Net of Tax Interest rate swap amounts reclassified into interest expense ​ $ (19,607) ​ $ 5,196 ​ $ (14,411) Changes in fair value of interest rate swaps ​ 10,588 ​ (2,806) ​ 7,782 Foreign currency translation adjustment ​ 53,633 ​ — ​ 53,633 ​ ​ $ 44,614 ​ $ 2,390 ​ $ 47,004 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2022 ​ Gross Tax Effect Net of Tax Interest rate swap amounts reclassified into interest expense ​ $ 6,551 ​ $ (1,736) ​ $ 4,815 Changes in fair value of interest rate swaps ​ 76,336 ​ (20,229) ​ 56,107 Foreign currency translation adjustment ​ ​ (157,336) ​ ​ — ​ ​ (157,336) ​ ​ $ (74,449) ​ $ (21,965) ​ $ (96,414)
Amounts Included in Accumulated Other Comprehensive Income (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, 2022 ​ $ 23,378 ​ $ (80,208) ​ $ (56,830) Amounts reclassified into earnings ​ (14,411) ​ — ​ (14,411) Changes in fair value ​ 7,782 ​ — ​ 7,782 Foreign currency translation adjustment ​ — ​ 53,633 ​ 53,633 Balance at December 31, 2023 ​ ​ 16,749 ​ ​ (26,575) ​ ​ (9,826) Amounts reclassified into earnings ​ ​ (15,043) ​ ​ — ​ ​ (15,043) Changes in fair value ​ ​ 8,531 ​ ​ — ​ ​ 8,531 Foreign currency translation adjustment ​ ​ — ​ ​ (189,402) ​ ​ (189,402) Balance at December 31, 2024 ​ $ 10,237 ​ $ (215,977) ​ $ (205,740) ​

INCOME TAXES (Tables)

INCOME TAXES (Tables)	12 Months Ended
	Dec. 31, 2024
INCOME TAXES
Income (Loss) Before Provision (Benefit) for Income Taxes	Income before provision for income taxes consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2024 2023 2022 U.S. ​ $ 343,255 ​ $ 622,041 ​ $ 734,126 Non – U.S. ​ 419,678 ​ 361,460 ​ 314,837 Income before income taxes ​ $ 762,933 ​ $ 983,501 ​ $ 1,048,963
Provision (Benefit) for Income Taxes	The provision for income taxes consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2024 2023 2022 Current: ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. Federal ​ $ 95,007 ​ $ 120,420 ​ $ 59,675 State ​ 42,725 ​ 50,713 ​ 28,770 Non – U.S. ​ 65,916 ​ 43,213 ​ 31,036 ​ ​ 203,648 ​ 214,346 ​ 119,481 Deferred: ​ ​ ​ U.S. Federal ​ (33,507) ​ 14,130 ​ 95,397 State ​ (5,833) ​ (1,931) ​ 16,840 Non – U.S. ​ (17,945) ​ (5,870) ​ (18,756) ​ ​ (57,285) ​ 6,329 ​ 93,481 Provision for income taxes ​ $ 146,363 ​ $ 220,675 ​ $ 212,962
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, ​ ​ 2024 2023 Deferred income tax assets: ​ ​ Accrued expenses ​ $ 38,674 ​ $ 33,358 Compensation ​ 26,589 ​ 25,781 Contingent liabilities ​ 16,237 ​ 27,154 Tax credits and loss carryforwards ​ 15,477 ​ 23,877 Landfill closure and post-closure ​ ​ 90,240 ​ ​ 12,476 Finance costs ​ 4,032 ​ 6,968 Other ​ ​ 13,306 ​ ​ 14,036 Gross deferred income tax assets ​ 204,555 ​ 143,650 Less: Valuation allowance ​ — ​ — Total deferred income tax assets ​ 204,555 ​ 143,650 ​ ​ ​ ​ ​ ​ ​ Deferred income tax liabilities: ​ ​ ​ ​ ​ ​ Goodwill and other intangibles ​ (472,608) ​ (471,074) Property and equipment ​ (595,156) ​ (602,453) Prepaid expenses ​ (19,737) ​ (15,428) Investment in subsidiaries ​ (71,703) ​ (71,136) Interest rate swaps ​ (3,691) ​ (6,039) Total deferred income tax liabilities ​ (1,162,895) ​ (1,166,130) Net deferred income tax liability ​ $ (958,340) ​ $ (1,022,480)
Differences between Income Tax Provision in Statements of Net Income and Income Tax Provision Computed at Federal Statutory Rate	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2024 2023 2022 U.S. federal statutory rate ​ 21.0 % 21.0 % 21.0 % State taxes, net of federal benefit 4.1 4.3 4.2 ​ Deferred income tax liability adjustments 0.7 0.3 — ​ Effect of international operations (3.8) (3.9) (4.0) ​ Federal tax credits (1.5) — (0.1) ​ Share-based compensation (0.7) (0.3) (0.2) ​ Other (0.6) 1.0 (0.6) ​ ​ 19.2 % 22.4 % 20.3 %

SEGMENT REPORTING (Tables)

SEGMENT REPORTING (Tables)	12 Months Ended
	Dec. 31, 2024
SEGMENT REPORTING
Summary of Financial Information Concerning Company's Reportable Segments	Summarized financial information concerning the Company’s reportable segments for the years ended December 31, 2024, 2023 and 2022, is shown in the following tables: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2024 Western Southern Eastern Central Canada MidSouth Corporate (a), (f) Consolidated Revenue ​ $ 2,034,370 ​ $ 1,984,150 ​ $ 1,875,559 ​ $ 1,696,559 ​ $ 1,385,869 ​ $ 1,218,482 ​ $ — ​ $ 10,194,989 ​ Intercompany revenue (b) ​ ​ (235,701) ​ ​ (226,957) ​ ​ (311,348) ​ ​ (181,657) ​ ​ (124,889) ​ ​ (194,846) ​ ​ — ​ ​ (1,275,398) ​ Reported revenue ​ 1,798,669 ​ ​ 1,757,193 ​ ​ 1,564,211 ​ ​ 1,514,902 ​ ​ 1,260,980 ​ ​ 1,023,636 ​ ​ — ​ 8,919,591 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment expenses (c) ​ ​ (1,277,911) ​ ​ (1,200,768) ​ ​ (1,146,988) ​ ​ (972,101) ​ ​ (709,501) ​ ​ (740,227) ​ ​ (27,655) ​ ​ (6,075,151) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment EBITDA (d) ​ 520,758 ​ ​ 556,425 ​ ​ 417,223 ​ ​ 542,801 ​ ​ 551,479 ​ ​ 283,409 ​ ​ (27,655) ​ 2,844,440 ​ Segment EBITDA margin ​ 29.0 % ​ 31.7 % ​ 26.7 % ​ 35.8 % ​ 43.7 % ​ 27.7 % ​ ​ ​ 31.9 % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Depreciation and amortization ​ ​ (211,111) ​ ​ (203,445) ​ ​ (230,466) ​ ​ (170,424) ​ ​ (200,274) ​ ​ (138,671) ​ ​ (9,378) ​ ​ (1,163,769) ​ Other segment items (e) ​ ​ (596,463) ​ ​ (9,395) ​ ​ (4,398) ​ ​ 1,483 ​ ​ 944 ​ ​ (33) ​ ​ (309,876) ​ ​ (917,738) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Income before income tax provision ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 762,933 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Capital expenditures ​ $ 198,849 ​ $ 190,912 ​ $ 191,817 ​ $ 174,805 ​ $ 147,596 ​ $ 129,373 ​ $ 22,636 ​ $ 1,055,988 ​ Total assets (g) ​ $ 3,512,253 ​ $ 3,885,522 ​ $ 3,544,234 ​ $ 2,827,108 ​ $ 3,564,052 ​ $ 2,022,594 ​ $ 462,046 ​ $ 19,817,809 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 Western Southern Eastern Central Canada MidSouth Corporate (a), (f) Consolidated Revenue ​ $ 1,878,843 ​ $ 1,846,713 ​ $ 1,639,351 ​ $ 1,620,908 ​ $ 1,109,164 ​ $ 1,072,753 ​ $ — ​ $ 9,167,732 ​ Intercompany revenue (b) ​ ​ (209,554) ​ ​ (204,439) ​ ​ (259,118) ​ ​ (180,751) ​ ​ (113,322) ​ ​ (178,597) ​ ​ — ​ ​ (1,145,781) ​ Reported revenue ​ 1,669,289 ​ ​ 1,642,274 ​ ​ 1,380,233 ​ ​ 1,440,157 ​ ​ 995,842 ​ ​ 894,156 ​ ​ — ​ 8,021,951 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment expenses (c) ​ ​ (1,186,084) ​ ​ (1,124,272) ​ ​ (1,027,172) ​ ​ (927,874) ​ ​ (605,178) ​ ​ (648,020) ​ ​ (25,032) ​ ​ (5,543,632) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment EBITDA (d) ​ 483,205 ​ ​ 518,002 ​ ​ 353,061 ​ ​ 512,283 ​ ​ 390,664 ​ ​ 246,136 ​ ​ (25,032) ​ 2,478,319 ​ Segment EBITDA margin ​ 28.9 % ​ 31.5 % ​ 25.6 % ​ 35.6 % ​ 39.2 % ​ 27.5 % ​ ​ ​ 30.9 % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Depreciation and amortization ​ ​ (199,426) ​ ​ (179,948) ​ ​ (207,909) ​ ​ (169,370) ​ ​ (121,326) ​ ​ (117,397) ​ ​ (7,835) ​ ​ (1,003,211) ​ Other segment items (e) ​ ​ (160,351) ​ ​ (11,165) ​ ​ (2,492) ​ ​ 6,763 ​ ​ (2,930) ​ ​ 3,783 ​ ​ (325,215) ​ ​ (491,607) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Income before income tax provision ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 983,501 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Capital expenditures ​ $ 192,148 ​ $ 166,961 ​ $ 143,484 ​ $ 171,748 ​ $ 105,453 ​ $ 135,650 ​ $ 18,556 ​ $ 934,000 ​ Total assets (g) ​ $ 3,432,529 ​ $ 3,501,953 ​ $ 3,228,244 ​ $ 2,811,016 ​ $ 2,794,795 ​ $ 1,705,180 ​ $ 442,159 ​ $ 17,915,876 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2022 Western Southern Eastern Central Canada MidSouth Corporate (a), (f) Consolidated Revenue ​ $ 1,605,574 ​ $ 1,670,864 ​ $ 1,445,193 ​ $ 1,447,703 ​ $ 1,047,672 ​ $ 992,922 ​ $ — ​ $ 8,209,928 ​ Intercompany revenue (b) ​ ​ (177,543) ​ ​ (176,425) ​ ​ (211,498) ​ ​ (159,355) ​ ​ (107,048) ​ ​ (166,200) ​ ​ — ​ ​ (998,069) ​ Reported revenue ​ 1,428,031 ​ ​ 1,494,439 ​ ​ 1,233,695 ​ ​ 1,288,348 ​ ​ 940,624 ​ ​ 826,722 ​ ​ — ​ 7,211,859 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment expenses (c) ​ ​ (1,003,096) ​ ​ (1,027,920) ​ ​ (952,173) ​ ​ (842,033) ​ ​ (591,221) ​ ​ (591,017) ​ ​ (25,019) ​ ​ (5,032,479) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Segment EBITDA (d) ​ 424,935 ​ ​ 466,519 ​ ​ 281,522 ​ ​ 446,315 ​ ​ 349,403 ​ ​ 235,705 ​ ​ (25,019) ​ 2,179,380 ​ Segment EBITDA margin ​ 29.8 % ​ 31.2 % ​ 22.8 % ​ 34.6 % ​ 37.1 % ​ 28.5 % ​ ​ ​ 30.2 % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Depreciation and amortization ​ ​ (155,882) ​ ​ (175,614) ​ ​ (190,480) ​ ​ (156,895) ​ ​ (118,388) ​ ​ (112,866) ​ ​ (8,835) ​ ​ (918,960) ​ Other segment items (e) ​ ​ (738) ​ ​ (7,330) ​ ​ (4,154) ​ ​ 5,368 ​ ​ (1,118) ​ ​ (3,606) ​ ​ (199,879) ​ ​ (211,457) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Income before income tax provision ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 1,048,963 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Capital expenditures ​ $ 232,714 ​ $ 151,093 ​ $ 138,028 ​ $ 181,065 ​ $ 70,051 ​ $ 133,849 ​ $ 5,877 ​ $ 912,677 ​ Total assets (g) ​ $ 3,239,679 ​ $ 3,410,888 ​ $ 2,752,436 ​ $ 2,803,853 ​ $ 2,773,882 ​ $ 1,727,323 ​ $ 426,542 ​ $ 17,134,603 ​ (a) The majority of Corporate expenses are allocated to the six 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 six 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) Segment expenses consist of all expenses that directly impact the CODM's primary financial measure, segment EBITDA. These expenses include cost of operations and selling, general, and administrative expenses as presented in the Company’s consolidated statements of operations. (d) 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. (e) For all geographic operating segments, other segment items consist of gains and losses on: disposal of assets, disposal of operations, litigation settlements, environmental remediation, real estate leases, landfill closure adjustments, contingent liability adjustments, impairments, foreign currency gains/losses and interest income. See Note 3 for more information relating to landfill closure adjustments and impairments recorded in the Western segment from the Company’s decision to cease active waste disposal operations at its Chiquita Canyon Landfill. (f) Corporate assets include cash, debt issuance costs, equity investments, operating lease right-of-use assets and corporate facility leasehold improvements and equipment. (g) Goodwill is included within total assets for each of the Company’s six operating segments.
Changes in Goodwill by Reportable Segment	The following table shows changes in goodwill during the years ended December 31, 2023 and 2024, by reportable segment: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Western Southern Eastern Central Canada MidSouth Total Balance as of December 31, 2022 ​ $ 732,335 ​ $ 1,547,894 ​ $ 1,189,111 ​ $ 1,003,470 ​ $ 1,684,670 ​ $ 744,817 ​ $ 6,902,297 Goodwill acquired ​ 47,120 ​ ​ 11,809 ​ ​ 398,380 ​ ​ 6,461 ​ ​ — ​ ​ 1,366 ​ 465,136 Goodwill acquisition adjustments ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ (2,215) ​ ​ — ​ ​ (2,215) Goodwill divested ​ ​ — ​ ​ — ​ ​ — ​ ​ (1,431) ​ ​ — ​ ​ — ​ ​ (1,431) Impact of changes in foreign currency ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 40,613 ​ ​ — ​ 40,613 Balance as of December 31, 2023 ​ ​ 779,455 ​ ​ 1,559,703 ​ ​ 1,587,491 ​ ​ 1,008,500 ​ ​ 1,723,068 ​ ​ 746,183 ​ ​ 7,404,400 Goodwill acquired ​ 85,147 ​ ​ 17,411 ​ ​ 148,093 ​ ​ 2,074 ​ ​ 343,531 ​ ​ 103,258 ​ 699,514 Impact of changes in foreign currency ​ — ​ — ​ — ​ — ​ (153,508) ​ — ​ (153,508) Balance as of December 31, 2024 ​ $ 864,602 ​ $ 1,577,114 ​ $ 1,735,584 ​ $ 1,010,574 ​ $ 1,913,091 ​ $ 849,441 ​ $ 7,950,406
Property and Equipment, Net for Reportable Segments	Property and equipment, net relating to operations in the United States and Canada are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2024 2023 United States ​ $ 6,870,901 ​ $ 6,456,319 Canada ​ 1,165,028 ​ 772,012 Total ​ $ 8,035,929 ​ $ 7,228,331 ​

Net Income Per Share Informat_2

Net Income Per Share Information (Tables)	12 Months Ended
	Dec. 31, 2024
Net Income Per Share Information [Abstract]
Basic and Diluted Net Income 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, 2024, 2023 and 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2024 2023 2022 Numerator: ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income attributable to Waste Connections for basic and diluted earnings per share ​ $ 617,573 ​ $ 762,800 ​ $ 835,662 Denominator: ​ ​ ​ ​ ​ ​ Basic shares outstanding ​ 257,965,871 ​ 257,551,129 ​ 257,383,578 Dilutive effect of equity-based awards ​ 696,319 ​ 598,115 ​ 655,223 Diluted shares outstanding ​ 258,662,190 ​ 258,149,244 ​ 258,038,801 ​

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2024
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 2024 2023 (b),(c) 2024 2023 2022 Agreement Western Conference of Teamsters Pension Trust 91-6145047 - 001 Green Green Not applicable ​ $ 9,676 ​ $ 8,747 ​ $ 5,803 12/31/2024 to 6/30/2028 Local 731, I.B. of T., Pension Fund 36-6513567 - 001 Green for the plan year beginning 10/1/2023 Green for the plan year beginning 10/1/2022 Not applicable ​ ​ 5,471 ​ ​ 4,939 ​ ​ 4,484 9/30/2028 Suburban Teamsters of Northern Illinois Pension Fund 36-6155778 - 001 Green Green Not applicable ​ 3,013 ​ 2,671 ​ 2,516 2/28/2029 Teamsters Local 301 Pension Fund 36-6492992 - 001 Green Green Not applicable ​ 1,314 ​ 1,183 ​ 1,310 9/30/2028 Midwest Operating Engineers Pension Plan 36-6140097 - 001 Green for the plan year beginning 4/1/2024 Green for the plan year beginning 4/1/2023 Not applicable ​ 774 ​ 704 ​ 542 10/31/2025 Automobile Mechanics’ Local No. 701 Union and Industry Pension Fund 36-6042061 - 001 Green Green Not applicable ​ 562 ​ 452 ​ 470 12/31/2025 Local 813 Pension Trust Fund 13-1975659 - 001 Critical and Declining for the plan year beginning 1/1/2024 Critical and Declining for the plan year beginning 1/1/2023 Implemented ​ 485 ​ 557 ​ 429 11/30/2027 IAM National Pension Fund 51-6031295 - 002 Critical Critical Implemented ​ 469 ​ 442 ​ 342 12/31/2025 Locals 302 & 612 of the IOUE - Employers Construction Industry Retirement Plan ​ 91-6028571 - 001 ​ Green ​ Green ​ Not applicable ​ ​ 355 ​ ​ 341 ​ ​ 338 ​ 11/30/2026 International Union of Operating Engineers Pension Trust 85512-1 Green as of 4/30/2022 Green as of 4/30/2022 Not applicable ​ 296 ​ 285 ​ 281 3/31/2025 to 3/31/2028 Multi-Sector Pension Plan 1085653 Critical as of 1/1/2022 Critical as of 1/1/2022 Not applicable ​ 274 ​ 246 ​ 249 12/31/2026 Recycling and General Industrial Union Local 108 Pension Fund ​ 13-6366378 - 001 ​ Green ​ Green ​ Not applicable ​ ​ 246 ​ ​ 225 ​ ​ 230 ​ 2/28/2027 Nurses and Local 813 IBT Retirement Plan ​ 13-3628926 - 001 ​ Green ​ Green ​ Not applicable ​ ​ 125 ​ ​ 121 ​ ​ 97 ​ 11/30/2027 Contributions to other multiemployer plans ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 98 ​ ​ 81 ​ ​ 65 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 23,158 ​ $ 20,994 ​ $ 17,156 ​ ​ ​ (a) Unless otherwise noted in the table above, the most recent Pension Protection Act zone status available in 2024 and 2023 is for the plans’ years ended December 31, 2023 and 2022, 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, 2024 and 2023 . (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, 2023, 2022 and 2021; 2) Suburban Teamsters of Northern Illinois Pension Plan for the plan years ending December 31, 2023, 2022 and 2021; 3) Teamsters Local 301 Pension Fund for plan years ending December 31, 2023, 2022 and 2021; 4) Local 813 Pension Trust Fund for the plan year ending December 31, 2023; and 5) Recycling and General Industrial Union Local 108 Pension Fund for the plan years ending December 31, 2023, 2022 and 2021.

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Revenue and Accounts Receivable - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Organization And Summary Of Significant Accounting Policies [Line Items]
Weighted average remaining contract life	5 years
Capitalized contract costs	$ 28,161	$ 25,977
Sales incentives amortization expense	$ 25,047	$ 25,855	$ 22,675
Minimum
Organization And Summary Of Significant Accounting Policies [Line Items]
Estimated life of relevant customer relationship	1 year
Maximum
Organization And Summary Of Significant Accounting Policies [Line Items]
Estimated life of relevant customer relationship	5 years
Landfill and transfer station | Minimum
Organization And Summary Of Significant Accounting Policies [Line Items]
Standard customer service agreement period	1 year
Landfill and transfer station | Maximum
Organization And Summary Of Significant Accounting Policies [Line Items]
Standard customer service agreement period	10 years
Collection | Minimum
Organization And Summary Of Significant Accounting Policies [Line Items]
Standard customer service agreement period	1 year
Collection | Maximum
Organization And Summary Of Significant Accounting Policies [Line Items]
Standard customer service agreement period	5 years

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Revenues by Service Line (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Revenue from External Customer [Line Items]
Revenues	$ 8,919,591	$ 8,021,951	$ 7,211,859
Reportable Segments | Collection
Revenue from External Customer [Line Items]
Revenues	6,332,773	5,934,979	5,251,027
Reportable Segments | Collection | Commercial
Revenue from External Customer [Line Items]
Revenues	2,670,549	2,476,891	2,176,295
Reportable Segments | Collection | Residential
Revenue from External Customer [Line Items]
Revenues	2,258,911	2,125,068	1,891,108
Reportable Segments | Collection | Industrial and construction roll off
Revenue from External Customer [Line Items]
Revenues	1,403,313	1,333,020	1,183,624
Reportable Segments | Landfill
Revenue from External Customer [Line Items]
Revenues	1,557,872	1,483,397	1,328,942
Reportable Segments | Transfer
Revenue from External Customer [Line Items]
Revenues	1,349,080	1,198,385	1,026,050
Reportable Segments | Recycling
Revenue from External Customer [Line Items]
Revenues	241,873	147,039	204,876
Reportable Segments | E&P
Revenue from External Customer [Line Items]
Revenues	521,504	232,211	210,562
Reportable Segments | Intermodal and other
Revenue from External Customer [Line Items]
Revenues	191,887	171,721	188,471
Intercompany Revenue
Revenue from External Customer [Line Items]
Revenues	$ (1,275,398)	$ (1,145,781)	$ (998,069)

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Allowance for Credit Losses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Summary of Significant Accounting Policies [Abstract]
Allowance for credit losses, beginning balance	$ 23,553	$ 22,939
Current period provision for expected credit losses	20,243	17,430	$ 17,353
Write-offs charged against the allowance	(23,141)	(22,743)
Recoveries collected	5,255	5,853
Impact of changes in foreign currency	(180)	74
Allowance for credit losses, ending balance	$ 25,730	$ 23,553	$ 22,939

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Property Plant and Equipment Estimated Useful Lives (Details)	Dec. 31, 2024
Buildings | Minimum
Property, Plant and Equipment [Line Items]
Useful life	10 years
Buildings | Maximum
Property, Plant and Equipment [Line Items]
Useful life	20 years
Leasehold and land improvements | Minimum
Property, Plant and Equipment [Line Items]
Useful life	3 years
Leasehold and land improvements | Maximum
Property, Plant and Equipment [Line Items]
Useful life	20 years
Machinery and equipment | Minimum
Property, Plant and Equipment [Line Items]
Useful life	3 years
Machinery and equipment | Maximum
Property, Plant and Equipment [Line Items]
Useful life	20 years
Rolling stock | Minimum
Property, Plant and Equipment [Line Items]
Useful life	3 years
Rolling stock | Maximum
Property, Plant and Equipment [Line Items]
Useful life	10 years
Containers | Minimum
Property, Plant and Equipment [Line Items]
Useful life	5 years
Containers | Maximum
Property, Plant and Equipment [Line Items]
Useful life	12 years

Summary of Significant Accoun_8

Summary of Significant Accounting Policies - Landfill Accounting - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Organization And Summary Of Significant Accounting Policies [Line Items]
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	381 years
Percentage of projected annual disposal volume from landfills with remaining lives within threshold period	90%
Threshold period used for measurement of projected annual disposal volume from landfills	70 years
Liability adjustments	$ 497,955	$ 189,136
Landfill
Organization And Summary Of Significant Accounting Policies [Line Items]
Inflation rate for purposes of computing layers for final capping, closure and post-closure obligations	2.75%	2.75%
Additional charges to adjust the carrying value of a closure and post-closure liability	$ 480,786	$ 159,547
Landfill | Measurement input, discount rate
Organization And Summary Of Significant Accounting Policies [Line Items]
Discount rate for purposes of computing layers for final capping, closure and post-closure obligations	5.50%	5.50%

Summary of Significant Accoun_9

Summary of Significant Accounting Policies - Final Capping, Closure and Post-Closure Liability Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Final capping, closure and post-closure liability at the beginning of the period	$ 522,233	$ 344,606
Liability adjustments	497,955	189,136
Accretion expense associated with landfill obligations	29,373	19,418
Closure payments	(247,552)	(39,429)
Assumption of closure liabilities from acquisitions	60,913	7,687
Foreign currency translation adjustment	(2,799)	815
Final capping, closure and post-closure liability at the end of the period	$ 860,123	$ 522,233

Summary of Significant Accou_10

Summary of Significant Accounting Policies - Intangible Assets - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($) segment	Dec. 31, 2023 USD ($) segment	Dec. 31, 2022 USD ($) segment
Organization And Summary Of Significant Accounting Policies [Line Items]
Number of reportable segments | segment	6	6	6
Forecasts period used for discounted cash flow analyses	10 years
Perpetual revenue growth rate	4.50%
Market participant rate	8.50%
Number of reporting units | segment	6	6	6
Impairments and other operating items	$ 613,012	$ 238,796	$ 18,230
Geographic Operating Segments
Organization And Summary Of Significant Accounting Policies [Line Items]
Impairment loss	0	$ 0	$ 0
Landfill | Chiquita Canyon, LLC
Organization And Summary Of Significant Accounting Policies [Line Items]
Impairment of long lived asset	$ 116,090
Minimum
Organization And Summary Of Significant Accounting Policies [Line Items]
Expected term of related agreements	4 years
Maximum
Organization And Summary Of Significant Accounting Policies [Line Items]
Expected term of related agreements	51 years

Summary of Significant Accou_11

Summary of Significant Accounting Policies - Restricted Cash and Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Restricted cash	$ 135,807	$ 105,639
Restricted investments	78,126	70,350
Restricted Settlement of insurance claims
Restricted cash	121,751	83,270
Restricted Landfill closure and post-closure obligations
Restricted cash	8,852	13,546
Restricted investments	77,855	68,266
Restricted Other financial assurance requirements
Restricted cash	5,204	8,823
Restricted investments	$ 271	$ 2,084

Summary of Significant Accou_12

Summary of Significant Accounting Policies - Fair Value of Financial Instruments - Carrying Values and Fair Values of Debt Instruments (Details) - Senior Notes - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Senior Notes due 2028
Debt Instrument [Line Items]
Carrying value of senior notes	$ 500,000	$ 500,000
Fair value of senior notes	$ 488,500	$ 496,800
Interest rate	4.25%	4.25%
Senior Notes due 2029
Debt Instrument [Line Items]
Carrying value of senior notes	$ 500,000	$ 500,000
Fair value of senior notes	$ 471,450	$ 478,350
Interest rate	3.50%	3.50%
New Senior Notes due 2029
Debt Instrument [Line Items]
Carrying value of senior notes	$ 347,500	$ 0
Fair value of senior notes	$ 359,168	0
Interest rate	4.50%
Senior Notes due 2030
Debt Instrument [Line Items]
Carrying value of senior notes	$ 600,000	600,000
Fair value of senior notes	$ 536,220	$ 539,460
Interest rate	2.60%	2.60%
Senior Notes due 2032
Debt Instrument [Line Items]
Carrying value of senior notes	$ 650,000	$ 650,000
Fair value of senior notes	$ 535,275	$ 543,725
Interest rate	2.20%	2.20%
New Senior Notes due 2032
Debt Instrument [Line Items]
Carrying value of senior notes	$ 500,000	$ 500,000
Fair value of senior notes	$ 437,150	$ 450,200
Interest rate	3.20%	3.20%
Senior Notes due 2033
Debt Instrument [Line Items]
Carrying value of senior notes	$ 750,000	$ 750,000
Fair value of senior notes	$ 696,300	$ 729,600
Interest rate	4.20%	4.20%
Senior Notes due 2034
Debt Instrument [Line Items]
Carrying value of senior notes	$ 750,000	$ 0
Fair value of senior notes	$ 731,625	0
Interest rate	5%
Senior Notes due 2050
Debt Instrument [Line Items]
Carrying value of senior notes	$ 500,000	500,000
Fair value of senior notes	$ 321,700	$ 362,600
Interest rate	3.05%	3.05%
Senior Notes due 2052
Debt Instrument [Line Items]
Carrying value of senior notes	$ 850,000	$ 850,000
Fair value of senior notes	$ 528,955	$ 601,460
Interest rate	2.95%	2.95%

Summary of Significant Accou_13

Summary of Significant Accounting Policies - Derivative Financial Instruments - Interest Rate Swaps (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($) agreement
Derivative [Line Items]
Number of interest rate swap agreements | agreement	4
Interest Rate Swap One
Derivative [Line Items]
Date entered	2017-08
Notional amount	$ 200,000
Fixed interest rate paid	2.123%
Variable interest rate received	1-month Term SOFR
Effective date	2022-11
Expiration date	2025-10
Interest Rate Swap Two
Derivative [Line Items]
Date entered	2018-06
Notional amount	$ 200,000
Fixed interest rate paid	2.848%
Variable interest rate received	1-month Term SOFR
Effective date	2022-11
Expiration date	2025-10
Interest Rate Swap Three
Derivative [Line Items]
Date entered	2018-06
Notional amount	$ 200,000
Fixed interest rate paid	2.8284%
Variable interest rate received	1-month Term SOFR
Effective date	2022-11
Expiration date	2025-10
Interest Rate Swap Four
Derivative [Line Items]
Date entered	2018-12
Notional amount	$ 200,000
Fixed interest rate paid	2.7715%
Variable interest rate received	1-month Term SOFR
Effective date	2022-11
Expiration date	2027-07

Summary of Significant Accou_14

Summary of Significant Accounting Policies - Derivative Financial Instruments - FV of Cash Flow Hedges (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Derivatives, Fair Value [Line Items]
Derivatives designated as cash flow hedges, asset derivatives	$ 13,929	$ 22,787
Interest rate swap
Derivatives, Fair Value [Line Items]
Derivatives designated as cash flow hedges, asset derivatives	10,545	15,842
Interest rate swap | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivatives designated as cash flow hedges, asset derivatives	10,545	15,842
Interest rate swap | Other assets
Derivatives, Fair Value [Line Items]
Derivatives designated as cash flow hedges, asset derivatives	$ 3,384	$ 6,945

Summary of Significant Accou_15

Summary of Significant Accounting Policies - Impact of CF Hedges on Operations, Comp Income and AOCIL (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized as AOCIL on Derivatives, Net of Tax	$ 8,531	$ 7,782	$ 56,107
Amount of (Gain) or Loss Reclassified from AOCIL into Earnings, Net of Tax	(15,043)	(14,411)	4,815
Interest rate swap
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized as AOCIL on Derivatives, Net of Tax	8,531	7,782	56,107
Amount of (Gain) or Loss Reclassified from AOCIL into Earnings, Net of Tax	(15,043)	(14,411)	4,815
Cash Flow Hedging | Interest rate swap
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized as AOCIL on Derivatives, Net of Tax	8,531	7,782	56,107
Cash Flow Hedging | Interest expense
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Gain) or Loss Reclassified from AOCIL into Earnings, Net of Tax	$ (15,043)	$ (14,411)	$ 4,815

Summary of Significant Accou_16

Summary of Significant Accounting Policies - Share-Based Compensation - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Organization And Summary Of Significant Accounting Policies [Line Items]
Contractual life of warrants	5 years
Share-based compensation expense, gross	$ 77,885	$ 70,436	$ 63,485
Share-based compensation expense, net of taxes	58,203	52,708	47,503
Restricted stock units (RSUs)
Organization And Summary Of Significant Accounting Policies [Line Items]
Unrecognized compensation cost related to unvested awards	$ 83,706
Restricted stock unit awards, vesting final year	2028
Weighted average remaining vesting period	1 year 2 months 12 days
Restricted stock units (RSUs) | Progressive Waste Plans
Organization And Summary Of Significant Accounting Policies [Line Items]
Share-based compensation liability	$ 8,068	$ 8,060	$ 8,042
Performance shares
Organization And Summary Of Significant Accounting Policies [Line Items]
Unrecognized compensation cost related to unvested awards	$ 14,877
Restricted stock unit awards, vesting final year	2027
Weighted average remaining vesting period	1 year 1 month 6 days
2020 Employee Share Purchase Plan | Minimum
Organization And Summary Of Significant Accounting Policies [Line Items]
Exercise price percentage of closing price of common shares	85%
2020 Employee Share Purchase Plan | Maximum
Organization And Summary Of Significant Accounting Policies [Line Items]
Exercise price percentage of closing price of common shares	95%

Summary of Significant Accou_17

Summary of Significant Accounting Policies - Advertising Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Advertising costs	$ 9,197	$ 9,097	$ 8,335

Summary of Significant Accou_18

Summary of Significant Accounting Policies - Insurance Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accrual for self insured liabilities	$ 243,764	$ 183,546
Self-insurance expense	$ 323,760	$ 261,589	$ 204,347

Prepaid Expenses and Other Cu_3

Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Prepaid Expenses And Other Current Assets [Line Items]
Income taxes receivable	$ 37,599	$ 28,124
Parts and supplies	71,156	61,673
Prepaid insurance	40,014	26,607
Unrealized cash flow hedge gains	13,929	22,787
Prepaid licenses and permits	14,141	13,898
Other	56,064	60,289
Total prepaid expenses and other current assets	229,519	206,433
Interest rate swap
Prepaid Expenses And Other Current Assets [Line Items]
Unrealized cash flow hedge gains	$ 10,545	$ 15,842

PROPERTY AND EQUIPMENT, NET - N

PROPERTY AND EQUIPMENT, NET - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Machinery and equipment
PROPERTY AND EQUIPMENT, NET
Finance lease right-of-use assets	$ 8,956	$ 9,762
Landfill
PROPERTY AND EQUIPMENT, NET
Landfill depletion expense	$ 289,696	$ 254,633	$ 232,251

PROPERTY AND EQUIPMENT, NET - P

PROPERTY AND EQUIPMENT, NET - Property and Equipment Schedule (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
PROPERTY AND EQUIPMENT, NET
Property and equipment gross	$ 14,630,957	$ 13,067,349
Less accumulated depreciation and depletion	(6,595,028)	(5,839,018)
Property, Plant and Equipment, Net, Total	8,035,929	7,228,331
Landfill
PROPERTY AND EQUIPMENT, NET
Property and equipment gross	5,778,483	5,507,596
Rolling stock
PROPERTY AND EQUIPMENT, NET
Property and equipment gross	3,428,765	3,084,623
Land, Buildings and Improvements [Member]
PROPERTY AND EQUIPMENT, NET
Property and equipment gross	2,328,287	1,807,719
Containers
PROPERTY AND EQUIPMENT, NET
Property and equipment gross	1,364,624	1,277,594
Machinery and equipment
PROPERTY AND EQUIPMENT, NET
Property and equipment gross	1,539,394	1,222,792
Construction in Progress [Member]
PROPERTY AND EQUIPMENT, NET
Property and equipment gross	$ 191,404	$ 167,025

LEASES - Narrative (Details)

LEASES - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
LEASES.
Operating lease impairment charge	$ 0	$ 0	$ 0
Finance lease impairment charge	$ 0	$ 0	$ 0

LEASES - Operating and Financin

LEASES - Operating and Financing Lease Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Lease, Cost [Abstract]
Operating lease cost	$ 53,329	$ 47,840	$ 41,891
Amortization of leased assets	3,375	2,852	2,484
Interest on leased liabilities	273	228	219
Total lease cost	$ 56,977	$ 50,920	$ 44,594

LEASES - Supplemental Cash Flow

LEASES - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
LEASES.
Operating cash flows from operating leases	$ 50,837	$ 46,688	$ 40,782
Operating cash flows from finance leases	273	228	219
Financing cash flows from finance leases	3,356	2,817	2,427
Right-of-use assets obtained in exchange for lease liabilities - operating leases	62,922	92,503	63,648
Right-of-use assets obtained in exchange for lease liabilities - finance leases	$ 2,569	$ 1,388	$ 3,369

LEASES - Weighted-Average Remai

LEASES - Weighted-Average Remaining Lease Term And Discount Rate (Details)	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
LEASES.
Weighted average remaining lease term - operating leases	9 years 8 months 12 days	10 years 10 months 24 days	8 years 10 months 24 days
Weighted average remaining lease term - finance leases	2 years 9 months 18 days	3 years 4 months 24 days	4 years 2 months 12 days
Weighted average discount rate - operating leases	4.34%	4.04%	2.93%
Weighted average discount rate - finance leases	2.99%	2.36%	1.96%

LEASES - Future Minimum Lease P

LEASES - Future Minimum Lease Payments (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Future Minimum Lease Payments, Operating Leases
2025	$ 53,080
2026	50,343
2027	46,834
2028	39,682
2029	32,950
Thereafter (year five)	170,462
Minimum lease payments	393,351
Less: imputed interest	(80,754)
Present value of minimum lease payments	312,597
Less: current portion of operating lease liabilities	(40,490)	$ (32,533)
Long-term portion of operating lease liabilities	272,107	238,440
Future Minimum Lease Payments, Finance Leases
2025	3,870
2026	3,284
2027	1,858
2028	540
2029	126
Minimum lease payments	9,678
Less: imputed interest, finance leases	(431)
Present value of minimum lease payments, finance leases	$ 9,247	$ 10,034
Finance Lease, Liability, Statement of Financial Position	Long-term portion of debt and notes payable, Current portion of long-term debt and notes payable	Long-term portion of debt and notes payable, Current portion of long-term debt and notes payable
Less: current portion of finance lease liabilities	$ (3,631)
Finance Lease, Liability, Current, Statement of Financial Position	Current portion of long-term debt and notes payable
Long-term portion of finance lease liabilities	$ 5,616
Finance Lease, Liability, Noncurrent, Statement of Financial Position	Long-term portion of debt and notes payable

ACQUISITIONS - Narrative (Detai

ACQUISITIONS - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($)	Dec. 31, 2024 USD ($) entity	Dec. 31, 2024 USD ($) agreement	Dec. 31, 2023 USD ($) entity	Dec. 31, 2022 USD ($) entity
ACQUISITIONS
Number of immaterial businesses acquired in period | entity					24
Acquisition-related costs	$ 26,059			$ 10,653	$ 24,933
Goodwill expected to be deductible for tax purposes	699,514	$ 699,514	$ 699,514	372,671	510,755
Trade receivables acquired in business combination gross contractual amount	106,259	106,259	106,259	19,202	54,332
Trade receivables acquired in business combination expected to be uncollectible amount	5,264	$ 5,264	$ 5,264	1,196	4,636
Number of individually immaterial acquisitions		7	7
Payment of contingent consideration recorded at acquisition date	$ 27,743			$ 13,317	$ 16,911
Solid waste
ACQUISITIONS
Number of immaterial businesses acquired in period | entity		20		12
E&P
ACQUISITIONS
Number of immaterial businesses acquired in period | entity		4		1

ACQUISITIONS - Consideration Tr

ACQUISITIONS - Consideration Transferred to Acquire Businesses and Assets Acquired, Liabilities Assumed Schedule (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($)	Dec. 31, 2024 USD ($) entity	Dec. 31, 2024 USD ($) agreement	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Fair value of consideration transferred:
Cash	$ 2,120,878			$ 676,793	$ 2,206,901
Debt assumed	77,766			76,001	127,136
Consideration transferred	2,198,644			752,794	2,334,037
Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired:
Accounts receivable	100,995	$ 100,995	$ 100,995	18,006	49,696
Prepaid expenses and other current assets	13,513	13,513	13,513	5,025	9,428
Restricted investments	0	0	0	5,462	7,469
Operating lease right-of-use assets	24,700	24,700	24,700	15,364	4,707
Property and equipment	913,729	913,729	913,729	207,164	1,073,155
Other assets	1,671	1,671	1,671	24	243
Accounts payable and accrued liabilities	(27,902)	(27,902)	(27,902)	(14,596)	(56,633)
Current portion of operating lease liabilities	(2,875)	(2,875)	(2,875)	(712)	(1,546)
Deferred revenue	(12,148)	(12,148)	(12,148)	(3,443)	(10,761)
Contingent consideration	(28,885)	(28,885)	(28,885)	(13,450)	(6,642)
Long-term portion of operating lease liabilities	(14,774)	(14,774)	(14,774)	(14,652)	(3,161)
Other long-term liabilities	(67,109)	(67,109)	(67,109)	(10,277)	(6,915)
Deferred income taxes				(3,212)	(51,507)
Total identifiable net assets	1,499,130	1,499,130	1,499,130	289,873	1,509,446
Goodwill	699,514			462,921	824,591
Goodwill expected to be deductible for tax purposes	699,514	$ 699,514	$ 699,514	372,671	510,755
Number of individually immaterial acquisitions		7	7
Trade receivables acquired in business combination gross contractual amount	106,259	$ 106,259	$ 106,259	19,202	54,332
Trade receivables acquired in business combination expected to be uncollectible amount	5,264	5,264	5,264	1,196	4,636
Long Term Franchise Agreements And Contracts
Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired:
Intangibles	159,028	159,028	159,028	76,401	239,866
Customer Lists
Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired:
Intangibles	214,459	214,459	214,459	19,719	74,940
Permits and Other
Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired:
Intangibles	$ 224,728	$ 224,728	$ 224,728	$ 3,050	$ 187,107

INTANGIBLE ASSETS, NET - Narrat

INTANGIBLE ASSETS, NET - Narrative (Details)	12 Months Ended
	Dec. 31, 2024
Long-term Franchise Agreements and Contracts
INTANGIBLE ASSETS, NET
Weighted average amortization period of acquired intangible assets	14 years 9 months 18 days
Customer Lists
INTANGIBLE ASSETS, NET
Weighted average amortization period of acquired intangible assets	10 years 1 month 6 days
Permits and Other
INTANGIBLE ASSETS, NET
Weighted average amortization period of acquired intangible assets	37 years 9 months 18 days

INTANGIBLE ASSETS, NET - Intang

INTANGIBLE ASSETS, NET - Intangible Assets Exclusive of Goodwill (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
INTANGIBLE ASSETS, NET
Gross Carrying Amount, Finite-Lived Intangible Assets	$ 3,109,297	$ 2,551,195
Gross Carrying Amount, Intangible Assets, Exclusive of Goodwill	3,290,910	2,732,808
Accumulated Amortization, Finite-Lived Intangible Assets	(1,258,507)	(1,088,483)
Accumulated Impairment Loss, Finite-Lived Intangible Assets	(40,784)	(40,784)
Net Carrying Amount, Finite-Lived Intangible Assets	1,810,006	1,421,928
Net Carrying Amount, Intangible Assets	1,991,619	1,603,541
Solid Waste Collection and Transportation Permits
INTANGIBLE ASSETS, NET
Net Carrying Amount, Indefinite-Lived Intangible Assets	181,613	181,613
Long-term Franchise Agreements and Contracts
INTANGIBLE ASSETS, NET
Gross Carrying Amount, Finite-Lived Intangible Assets	1,104,585	960,033
Accumulated Amortization, Finite-Lived Intangible Assets	(400,674)	(343,099)
Net Carrying Amount, Finite-Lived Intangible Assets	703,911	616,934
Customer Lists
INTANGIBLE ASSETS, NET
Gross Carrying Amount, Finite-Lived Intangible Assets	1,005,355	806,257
Accumulated Amortization, Finite-Lived Intangible Assets	(693,594)	(606,192)
Net Carrying Amount, Finite-Lived Intangible Assets	311,761	200,065
Permits and Other
INTANGIBLE ASSETS, NET
Gross Carrying Amount, Finite-Lived Intangible Assets	999,357	784,905
Accumulated Amortization, Finite-Lived Intangible Assets	(164,239)	(139,192)
Accumulated Impairment Loss, Finite-Lived Intangible Assets	(40,784)	(40,784)
Net Carrying Amount, Finite-Lived Intangible Assets	$ 794,334	$ 604,929

INTANGIBLE ASSETS, NET - Estima

INTANGIBLE ASSETS, NET - Estimated Future Amortization Expense, Intangible Assets (Details) $ in Thousands	Dec. 31, 2024 USD ($)
INTANGIBLE ASSETS, NET
For the year ending December 31, 2025	$ 180,792
For the year ending December 31, 2026	157,827
For the year ending December 31, 2027	137,790
For the year ending December 31, 2028	122,230
For the year ending December 31, 2029	$ 110,584

ACCRUED LIABILITIES (Details)

ACCRUED LIABILITIES (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
ACCRUED LIABILITIES
Insurance claims and premiums	$ 244,536	$ 184,403
Payroll and payroll-related	127,518	108,423
Interest payable	68,455	52,726
Final capping, closure and post-closure liability - current portion	199,736	92,946
Property taxes	17,548	15,545
Environmental remediation reserve - current portion	8,808	10,860
Environmental remediation reserve - non current portion	$ 7,186	$ 4,289
Environmental Loss Contingency, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other Liabilities, Noncurrent	Other Liabilities, Noncurrent
Cell processing reserve - current portion	$ 2,148	$ 3,246
Transaction-related expenses	1,471	958
Other	66,604	52,321
Accrued Liabilities, Current, Total	$ 736,824	$ 521,428

Long-Term Debt - Schedule of LT

Long-Term Debt - Schedule of LTD and Lease Obligations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2024
Debt Instrument [Line Items]
Finance leases	$ 10,034	$ 9,247
Total debt and lease obligations	6,812,053	8,151,713
Less - current portion	(26,462)	(7,851)
Less - unamortized debt discount and issuance costs	(60,820)	(70,934)
Long-term portion of debt and notes payable	6,724,771	$ 8,072,928
Minimum
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Finance leases interest rate		1.89%
Maximum
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Finance leases interest rate		5.07%
Revolving Credit Agreement | Revolving Credit Facility
Debt Instrument [Line Items]
Long term debt	0	$ 2,164,325
Revolving Credit Agreement | Revolving Credit Facility | Minimum
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Line of credit, interest rate		4.59%
Revolving Credit Agreement | Revolving Credit Facility | Maximum
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Line of credit, interest rate		7.50%
Revolving And Term Credit Agreement 2021 | Revolving Credit Facility
Debt Instrument [Line Items]
Long term debt	$ 453,245	$ 0
Revolving And Term Credit Agreement 2021 | Revolving Credit Facility | Minimum
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Line of credit, interest rate	6.40%
Revolving And Term Credit Agreement 2021 | Revolving Credit Facility | Maximum
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Line of credit, interest rate	8.50%
Notes Payable to Sellers and Other Third Parties
Debt Instrument [Line Items]
Long term debt	$ 48,774	$ 30,641
Notes Payable to Sellers and Other Third Parties | Minimum
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Interest rate		2.42%
Notes Payable to Sellers and Other Third Parties | Maximum
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Interest rate		10.35%
Term Loan Facility | Revolving And Term Credit Agreement 2021
Debt Instrument [Line Items]
Long term debt	$ 650,000	$ 0
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Line of credit, interest rate	6.50%
Term Loan Facility | Term Loan Agreement 2022
Debt Instrument [Line Items]
Long term debt	$ 800,000	0
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Line of credit, interest rate	6.44%
Margin rate for loans	1%
Senior Notes | Senior Notes due 2028
Debt Instrument [Line Items]
Long term debt	$ 500,000	$ 500,000
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Interest rate	4.25%	4.25%
Senior Notes | Senior Notes due 2029
Debt Instrument [Line Items]
Long term debt	$ 500,000	$ 500,000
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Interest rate	3.50%	3.50%
Senior Notes | New Senior Notes due 2029
Debt Instrument [Line Items]
Long term debt	$ 0	$ 347,500
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Interest rate		4.50%
Senior Notes | Senior Notes due 2030
Debt Instrument [Line Items]
Long term debt	$ 600,000	$ 600,000
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Interest rate	2.60%	2.60%
Senior Notes | Senior Notes due 2032
Debt Instrument [Line Items]
Long term debt	$ 650,000	$ 650,000
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Interest rate	2.20%	2.20%
Senior Notes | New Senior Notes due 2032
Debt Instrument [Line Items]
Long term debt	$ 500,000	$ 500,000
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Interest rate	3.20%	3.20%
Senior Notes | Senior Notes due 2033
Debt Instrument [Line Items]
Long term debt	$ 750,000	$ 750,000
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Interest rate	4.20%	4.20%
Senior Notes | Senior Notes due 2034
Debt Instrument [Line Items]
Long term debt	$ 0	$ 750,000
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Interest rate		5%
Senior Notes | Senior Notes due 2050
Debt Instrument [Line Items]
Long term debt	$ 500,000	$ 500,000
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Interest rate	3.05%	3.05%
Senior Notes | Senior Notes due 2052
Debt Instrument [Line Items]
Long term debt	$ 850,000	$ 850,000
Debt Instrument, Interest Rate, Stated Percentage [Abstract]
Interest rate	2.95%	2.95%

Long-Term Debt - Revolving Cred

Long-Term Debt - Revolving Credit Agreement Schedule (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Revolving Credit Agreement | SOFR
Debt Instrument [Line Items]
Margin rate for loans	0.10%
Revolving Credit Agreement | Revolving Credit Facility
Debt Instrument [Line Items]
Available	$ 778,374
Amount drawn	$ 2,164,325	$ 0
Commitment - rate applicable	0.09%
Revolving Credit Agreement | Revolving Credit Facility | SOFR | Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Amount drawn	$ 800,000
Interest rate applicable	5.65%
Margin rate for loans	1%
Revolving Credit Agreement | Revolving Credit Facility | SOFR | Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Amount drawn	$ 500,000
Interest rate applicable	5.69%
Margin rate for loans	1%
Revolving Credit Agreement | Revolving Credit Facility | SOFR | Debt Instrument, Redemption, Period Three
Debt Instrument [Line Items]
Amount drawn	$ 50,000
Interest rate applicable	5.46%
Margin rate for loans	1%
Revolving Credit Agreement | Revolving Credit Facility | Base Rate
Debt Instrument [Line Items]
Amount drawn	$ 95,000
Interest rate applicable	7.50%
Margin rate for loans	0%
Revolving Credit Agreement | Revolving Credit Facility | CORRA | Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Amount drawn	$ 590,750
Interest rate applicable	5.24%
Margin rate for loans	1%
Revolving Credit Agreement | Revolving Credit Facility | CORRA | Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Amount drawn	$ 86,875
Interest rate applicable	4.59%
Margin rate for loans	1%
Revolving Credit Agreement | Revolving Credit Facility | Canadian Prime Rate
Debt Instrument [Line Items]
Amount drawn	$ 41,700
Interest rate applicable	5.45%
Margin rate for loans	0%
Revolving Credit Agreement | Revolving Credit Facility | Canadian Bankers Acceptance Loan | Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Amount drawn	$ 0
Interest rate applicable	0%
Margin rate for loans	0%
Revolving Credit Agreement | Revolving Credit Facility | Canadian Bankers Acceptance Loan | Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Amount drawn	$ 0
Interest rate applicable	0%
Margin rate for loans	0%
Revolving Credit Agreement | Letter of Credit
Debt Instrument [Line Items]
Letter of credit	$ 57,301
Revolving Credit Agreement | Term Loan Facility | SOFR
Debt Instrument [Line Items]
Amount drawn	$ 0
Interest rate applicable	0%
Margin rate for loans	0%
Revolving And Term Credit Agreement 2021 | Revolving Credit Facility
Debt Instrument [Line Items]
Available		1,357,013
Amount drawn	$ 0	$ 453,245
Commitment - rate applicable		0.09%
Revolving And Term Credit Agreement 2021 | Revolving Credit Facility | SOFR | Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Amount drawn		$ 90,000
Interest rate applicable		6.46%
Margin rate for loans		1%
Revolving And Term Credit Agreement 2021 | Revolving Credit Facility | SOFR | Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Amount drawn		$ 150,000
Interest rate applicable		6.50%
Margin rate for loans		1%
Revolving And Term Credit Agreement 2021 | Revolving Credit Facility | SOFR | Debt Instrument, Redemption, Period Three
Debt Instrument [Line Items]
Amount drawn		$ 0
Interest rate applicable		0%
Margin rate for loans		0%
Revolving And Term Credit Agreement 2021 | Revolving Credit Facility | Base Rate
Debt Instrument [Line Items]
Amount drawn		$ 28,000
Interest rate applicable		8.50%
Margin rate for loans		0%
Revolving And Term Credit Agreement 2021 | Revolving Credit Facility | CORRA | Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Amount drawn		$ 0
Interest rate applicable		0%
Margin rate for loans		0%
Revolving And Term Credit Agreement 2021 | Revolving Credit Facility | CORRA | Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Amount drawn		$ 0
Interest rate applicable		0%
Margin rate for loans		0%
Revolving And Term Credit Agreement 2021 | Revolving Credit Facility | Canadian Prime Rate
Debt Instrument [Line Items]
Amount drawn		$ 15,122
Interest rate applicable		7.20%
Margin rate for loans		0%
Revolving And Term Credit Agreement 2021 | Revolving Credit Facility | Canadian Bankers Acceptance Loan | Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Amount drawn		$ 153,111
Interest rate applicable		6.46%
Margin rate for loans		1%
Revolving And Term Credit Agreement 2021 | Revolving Credit Facility | Canadian Bankers Acceptance Loan | Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Amount drawn		$ 17,012
Interest rate applicable		6.40%
Margin rate for loans		1%
Revolving And Term Credit Agreement 2021 | Letter of Credit
Debt Instrument [Line Items]
Letter of credit		$ 39,742
Revolving And Term Credit Agreement 2021 | Term Loan Facility | SOFR
Debt Instrument [Line Items]
Amount drawn		$ 650,000
Interest rate applicable		6.50%
Margin rate for loans		1%

Long-Term Debt - Revolving Cr_2

Long-Term Debt - Revolving Credit Agreement Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
SOFR Loans, CORRA Loans, and Letters of Credit | Minimum
Debt Instrument [Line Items]
Margin rate for loans	0.75%
SOFR Loans, CORRA Loans, and Letters of Credit | Maximum
Debt Instrument [Line Items]
Margin rate for loans	1.25%
Revolving Credit Agreement
Debt Instrument [Line Items]
Covenant description	as of the last day of each fiscal quarter, the ratio of (a) Consolidated Total Funded Debt (as defined in the Revolving Credit Agreement) as of such date to (b) Consolidated EBITDA (as defined in the Revolving 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).
Debt Instrument, Covenant Compliance	As of December 31, 2024, the Company was in compliance with all applicable covenants in the Revolving Credit Agreement
Revolving Credit Agreement | Other assets
Debt Instrument [Line Items]
Prepaid expense, debt issuance costs	$ 4,401
Revolving Credit Agreement | Maximum
Debt Instrument [Line Items]
Required Leverage Ratio	3.75
Required leverage ratio during material acquisition period	4.25
Revolving Credit Agreement | CORRA | One Month
Debt Instrument [Line Items]
Margin rate for loans	0.29547%
Revolving Credit Agreement | CORRA | Three Months
Debt Instrument [Line Items]
Margin rate for loans	0.32138%
Revolving Credit Agreement | SOFR
Debt Instrument [Line Items]
Margin rate for loans	0.10%
Revolving Credit Agreement | Letter of Credit
Debt Instrument [Line Items]
Letter of credit	$ 57,301
Revolving Credit Agreement | Letter of Credit | Maximum
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity	$ 320,000
Revolving Credit Agreement | Revolving Credit Facility
Debt Instrument [Line Items]
Maturity date	Feb. 27, 2029
Credit facility maximum borrowing capacity	$ 3,000,000
Upsize available to credit facility maximum borrowing capacity	$ 1,000,000
Revolving Credit Agreement | Revolving Credit Facility | Minimum
Debt Instrument [Line Items]
Commitment Fee, Percentage	0.065%
Revolving Credit Agreement | Revolving Credit Facility | Maximum
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity	$ 4,000,000
Commitment Fee, Percentage	0.15%
Revolving Credit Agreement | Revolving Credit Facility | Base Rate
Debt Instrument [Line Items]
Margin rate for loans	0%
Revolving Credit Agreement | Revolving Credit Facility | Canadian Prime Rate
Debt Instrument [Line Items]
Margin rate for loans	0%
Revolving Credit Agreement | Swing Line Loans | Maximum
Debt Instrument [Line Items]
Swing line loans	$ 100,000
Revolving And Term Credit Agreement 2021 | Letter of Credit
Debt Instrument [Line Items]
Letter of credit		$ 39,742
Revolving And Term Credit Agreement 2021 | Revolving Credit Facility | Base Rate
Debt Instrument [Line Items]
Margin rate for loans		0%
Revolving And Term Credit Agreement 2021 | Revolving Credit Facility | Canadian Prime Rate
Debt Instrument [Line Items]
Margin rate for loans		0%
Facilities Other Than Revolving Credit Agreement | Letter of Credit
Debt Instrument [Line Items]
Letter of credit	$ 113,385
Canadian Prime Rate Loans and Swing Line Loans | Base Rate | Minimum
Debt Instrument [Line Items]
Margin rate for loans	0%
Canadian Prime Rate Loans and Swing Line Loans | Base Rate | Maximum
Debt Instrument [Line Items]
Margin rate for loans	0.25%

Long-Term Debt - Senior Notes N

Long-Term Debt - Senior Notes Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($)	Dec. 31, 2023	Jun. 13, 2024 CAD ($)	Feb. 21, 2024 USD ($)	Aug. 18, 2022 USD ($)	Mar. 09, 2022 USD ($)	Sep. 20, 2021 USD ($)	Mar. 13, 2020 USD ($)	Jan. 23, 2020 USD ($)	Apr. 16, 2019 USD ($)	Nov. 16, 2018 USD ($)
Revolving Credit Agreement | SOFR
Debt Instrument [Line Items]
Margin rate for loans	0.10%
Revolving Credit Agreement | Revolving Credit Facility
Debt Instrument [Line Items]
Maturity date	Feb. 27, 2029
Commitment - rate applicable	0.09%
Revolving Credit Agreement | Revolving Credit Facility | Canadian Prime Rate
Debt Instrument [Line Items]
Margin rate for loans	0%
Revolving Credit Agreement | Term Loan Facility | SOFR
Debt Instrument [Line Items]
Margin rate for loans	0%
Revolving And Term Credit Agreement 2021 | Revolving Credit Facility
Debt Instrument [Line Items]
Commitment - rate applicable		0.09%
Revolving And Term Credit Agreement 2021 | Revolving Credit Facility | Canadian Prime Rate
Debt Instrument [Line Items]
Margin rate for loans		0%
Revolving And Term Credit Agreement 2021 | Term Loan Facility | SOFR
Debt Instrument [Line Items]
Margin rate for loans		1%
Senior Notes
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage	100%
Senior Notes | Minimum
Debt Instrument [Line Items]
Percentage of principal amount redeemed	25%
Senior Notes | Maximum
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage	101%
Senior Notes | Senior Notes due 2028
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage	100%
Aggregate principal amount											$ 500,000
Interest rate	4.25%	4.25%
Maturity date	Dec. 01, 2028
Debt issuance costs	$ 5,792
Debt instrument, redemption period	Sep. 01, 2028
Senior Notes | Senior Notes due 2029
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage	100%
Aggregate principal amount										$ 500,000
Interest rate	3.50%	3.50%
Maturity date	May 01, 2029
Debt issuance costs	$ 5,954
Debt instrument, redemption period	Feb. 01, 2029
Senior Notes | New Senior Notes due 2029
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage	100%
Aggregate principal amount			$ 500,000,000
Interest rate	4.50%
Maturity date	Jun. 14, 2029
Debt issuance costs	$ 2,656
Debt discount	$ 245
Debt instrument, redemption period	May 14, 2029
Senior Notes | Senior Notes due 2030
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage	100%
Aggregate principal amount									$ 600,000
Interest rate	2.60%	2.60%
Maturity date	Feb. 01, 2030
Debt issuance costs	$ 5,435
Debt instrument, redemption period	Nov. 01, 2029
Senior Notes | Senior Notes due 2032
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage	100%
Aggregate principal amount							$ 650,000
Interest rate	2.20%	2.20%
Maturity date	Jan. 15, 2032
Debt issuance costs	$ 5,979
Debt discount	$ 1,066
Debt instrument, redemption period	Oct. 15, 2031
Senior Notes | New Senior Notes due 2032
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage	100%
Aggregate principal amount						$ 500,000
Interest rate	3.20%	3.20%
Maturity date	Jun. 01, 2032
Debt issuance costs	$ 4,668
Debt discount	$ 375
Debt instrument, redemption period	Mar. 01, 2032
Senior Notes | Senior Notes due 2033
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage	100%
Aggregate principal amount					$ 750,000
Interest rate	4.20%	4.20%
Maturity date	Jan. 15, 2033
Debt issuance costs	$ 6,878
Debt discount	$ 2,040
Debt instrument, redemption period	Oct. 15, 2032
Senior Notes | Senior Notes due 2034
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage	100%
Aggregate principal amount				$ 750,000
Interest rate	5%
Maturity date	Mar. 01, 2034
Debt issuance costs	$ 6,978
Debt discount	$ 8,738
Debt instrument, redemption period	Dec. 01, 2033
Senior Notes | Senior Notes due 2050
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage	100%
Aggregate principal amount								$ 500,000
Interest rate	3.05%	3.05%
Maturity date	Apr. 01, 2050
Debt issuance costs	$ 5,682
Debt discount	$ 7,375
Debt instrument, redemption period	Oct. 01, 2049
Senior Notes | Senior Notes due 2052
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage	100%
Aggregate principal amount							$ 850,000
Interest rate	2.95%	2.95%
Maturity date	Jan. 15, 2052
Debt issuance costs	$ 9,732
Debt discount	$ 12,742
Debt instrument, redemption period	Jul. 15, 2051

Long-Term Debt - Future Princip

Long-Term Debt - Future Principal Payments Schedule (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Long-Term Debt [Abstract]
2025	$ 7,851
2026	7,249
2027	6,030
2028	504,864
2029	3,016,290
Thereafter	4,609,429
Total debt and lease obligations	$ 8,151,713	$ 6,812,053

FAIR VALUE OF FINANCIAL INSTR_3

FAIR VALUE OF FINANCIAL INSTRUMENTS - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
FAIR VALUE OF FINANCIAL INSTRUMENTS
Restricted cash	$ 135,807	$ 105,639
Fair Value, Measurements, Recurring
FAIR VALUE OF FINANCIAL INSTRUMENTS
Restricted cash	135,807	105,639
Restricted investments	77,900	70,658
Contingent consideration	(87,162)	(115,030)
Fair Value, Measurements, Recurring | Interest rate swap
FAIR VALUE OF FINANCIAL INSTRUMENTS
Derivative instrument - net	13,929	22,787
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1
FAIR VALUE OF FINANCIAL INSTRUMENTS
Restricted cash	135,807	105,639
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
FAIR VALUE OF FINANCIAL INSTRUMENTS
Restricted investments	77,900	70,658
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Interest rate swap
FAIR VALUE OF FINANCIAL INSTRUMENTS
Derivative instrument - net	13,929	22,787
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3
FAIR VALUE OF FINANCIAL INSTRUMENTS
Contingent consideration	$ (87,162)	$ (115,030)

FAIR VALUE OF FINANCIAL INSTR_4

FAIR VALUE OF FINANCIAL INSTRUMENTS - Change in FV for Level 3 Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
FAIR VALUE OF FINANCIAL INSTRUMENTS
Beginning balance	$ 115,030	$ 81,415
Contingent consideration recorded at acquisition date	28,885	13,450
Payment of contingent consideration recorded at acquisition date	(27,743)	$ (13,317)
Payment of contingent consideration recorded in earnings	$ (35,035)
Payment of contingent consideration recorded in earnings, location	Impairments and other operating items	Impairments and other operating items
Adjustments to contingent consideration	$ (3)	$ 30,367	$ (1,030)
Interest accretion expense	6,217	3,115
Foreign currency translation adjustment	(189)
Ending balance	$ 87,162	$ 115,030	$ 81,415

COMMITMENTS AND CONTINGENCIES -

COMMITMENTS AND CONTINGENCIES - Narrative (Details) T in Thousands, gal in Millions				7 Months Ended	12 Months Ended
	Aug. 09, 2024 USD ($)	Aug. 10, 2018 USD ($)	Mar. 06, 2018 USD ($)	Jul. 25, 2017 USD ($)	Dec. 31, 2024 USD ($) employee agreement T gal	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
COMMITMENTS AND CONTINGENCIES
Amount of surety bonds to secure asset closure and retirement requirements					$ 934,330,000	$ 901,283,000
Amount of surety bonds to secure performance under collection contracts and landfill operating agreements					$ 1,077,021,000	743,816,000
Percentage of interest in company that issues financial surety bonds					9.90%
Outstanding amount of financial surety bonds					$ 492,711,000	470,416,000
Unrecorded unconditional purchase obligation, remaining volume | gal					59.7
Purchase commitment					$ 179,272,000
Purchase obligation company paid					139,973,000	$ 145,598,000	$ 112,136,000
Threshold used for disclosing environmental matters involving potential monetary sanctions					$ 1,000,000
Collective bargaining agreements number of employees | employee					3,774
Collective bargaining agreements percentage of workforce					16%
Number of collective bargaining agreements expired or set to expire | agreement					25
Collective bargaining agreements of workforce					7%
Workforce Subject to Collective-Bargaining Arrangements Expiring within One Year [Member]
COMMITMENTS AND CONTINGENCIES
Collective bargaining agreements of employees | employee					1,603
Bridge and Thoroughfare Fee
COMMITMENTS AND CONTINGENCIES
Loss contingency amount sought			$ 83,000	$ 11,600,000
Noncompliance fee			$ 750
Jefferson Parish, Louisiana Landfill Litigation
COMMITMENTS AND CONTINGENCIES
Loss contingency amount sought	$ 4,500,000
Chiquita Canyon, LLC
COMMITMENTS AND CONTINGENCIES
Annual tons of waste accepted at landfill | T					2,250
Estimate of total new fees and other new taxes over the life of the conditional use permit					$ 300,000,000
Penalties | Bridge and Thoroughfare Fee
COMMITMENTS AND CONTINGENCIES
Fee paid		$ 83,000
Fees | Bridge and Thoroughfare Fee
COMMITMENTS AND CONTINGENCIES
Fee paid		$ 750

COMMITMENTS AND CONTINGENCIES_2

COMMITMENTS AND CONTINGENCIES - Future Minimum Purchase Commitments (Details) $ in Thousands	Dec. 31, 2024 USD ($)
COMMITMENTS AND CONTINGENCIES.
2025	$ 140,123
2026	37,284
2027	778
2028	621
2029	466
Thereafter	0
Total purchase commitment	$ 179,272

Shareholders' Equity - Narrativ

Shareholders' Equity - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended	5 Months Ended	6 Months Ended	12 Months Ended			103 Months Ended
	Oct. 31, 2024	Sep. 30, 2024	Dec. 31, 2024	Jul. 31, 2024	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2024	Jul. 23, 2024	Jun. 01, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of shares under employee share purchase plan, shares					29,256	29,808	26,582
Issuance of shares under employee share purchase plan					$ 4,486	$ 3,909	$ 3,270
Cash dividend per common share, increase	$ 0.03
Cash dividend per share	$ 0.315	$ 0.285			$ 1.17	$ 1.05	$ 0.945
Maximum number of shares authorized for repurchase									12,901,981
Share repurchase plan expiration date			Aug. 11, 2025
Daily repurchase of shares, maximum				60,089
Daily Shares Repurchase (as percentage)			25%		25%			25%
Repurchase of common stock (shares)					0	0	3,388,155
Common shares, shares issued			258,067,487		258,067,487	257,659,921		258,067,487
Preferred stock, shares issued			0		0	0	0	0
Average daily trading volume during period				240,359
Aggregate cost of stock repurchased							$ 424,999
Aggregate cost of common stock repurchase			$ 0		$ 0	$ 0		$ 0
Maximum remaining number of shares available for repurchase			12,901,981		12,901,981			12,901,981
Cash dividends on common stock					$ 302,258	$ 270,604	$ 243,013
Shares reserved for issuance			4,979,960		4,979,960			4,979,960
2020 Employee Share Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum percent of eligible compensation to purchase shares			1%		1%			1%
Maximum percent of eligible compensation to purchase shares			10%		10%			10%
Maximum number of share authorized to be issued under plan			1,000,000		1,000,000			1,000,000
2016 Incentive Award Plan
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
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant expiration					2025
Minimum | 2020 Employee Share Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price percentage of closing price of common shares					85%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant expiration					2029
Maximum | 2020 Employee Share Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price percentage of closing price of common shares					95%
Restricted stock units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested deferred RSUs outstanding			29,980		29,980	49,129	81,352	29,980
Weighted average grant-date fair value of award					$ 164.93	$ 133.65	$ 121.26
Units granted in period					371,343
Restricted stock units (RSUs) | 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) | Progressive Waste Solutions Ltd.
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted in period								0
Performance shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant-date fair value of award					$ 138.29	$ 133.83	$ 117.94
Units granted in period					113,166
Performance shares | 2022 Performance-Based Restricted Share Units, Plan One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award							3 years
Performance period end date							Dec. 31, 2024
Performance shares | 2023 Performance-Based Restricted Share Units, Plan One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award						3 years
Performance period end date						Dec. 31, 2025
Performance shares | 2024 Performance-Based Restricted Share Units, Plan One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award					3 years
Performance period end date					Dec. 31, 2026
Special Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares, shares issued			0		0	0	0	0
Deferred share units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested deferred RSUs outstanding			20,418		20,418	30,481		20,418
Weighted average grant-date fair value of award					$ 168.71	$ 136.47	$ 121
Units granted in period					3,746
Restricted Share Units and Deferred Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Sale of common shares held in trust, shares					11,344	6,017	5,203
Restricted Share Units and Deferred Share Units | Progressive Waste Solutions Ltd.
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Acquired common shares held in trust			48,098		48,098			48,098		735,171
2016 Incentive Award Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance			1,993,310		1,993,310			1,993,310
2020 Employee Share Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance			903,541		903,541			903,541
Restricted Stock Units Performance Share Units and Warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance			2,083,109		2,083,109			2,083,109
Progressive Waste Solutions Ltd. | Restricted stock units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested deferred RSUs outstanding			45,466		45,466	51,812		45,466

Shareholders' Equity - Restrict

Shareholders' Equity - Restricted Stock Units Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Restricted stock units (RSUs)
Schedule of Share based Compensation Arrangements by Share based Payment Award, Equity Instruments, Other Than Options, Restricted Stock Units [Line Items]
Stock units granted	371,343
Weighted average grant-date fair value of award	$ 164.93	$ 133.65	$ 121.26
Total fair value of share units vested	$ 39,745	$ 39,754	$ 28,751
Performance shares
Schedule of Share based Compensation Arrangements by Share based Payment Award, Equity Instruments, Other Than Options, Restricted Stock Units [Line Items]
Stock units granted	113,166
Weighted average grant-date fair value of award	$ 138.29	$ 133.83	$ 117.94
Total fair value of share units vested	$ 14,948	$ 20,196	$ 4,674
Deferred share units
Schedule of Share based Compensation Arrangements by Share based Payment Award, Equity Instruments, Other Than Options, Restricted Stock Units [Line Items]
Stock units granted	3,746
Weighted average grant-date fair value of award	$ 168.71	$ 136.47	$ 121
Total fair value of share units awarded	$ 632	$ 538	$ 253

10-K Shareholders' Equity (Summ

10-K Shareholders' Equity (Summary of Activity Related to Restricted Stock Units) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Restricted stock units (RSUs)
Unvested shares
Outstanding at beginning	49,129	81,352
Outstanding, shares at beginning	936,267
Granted	371,343
Forfeited	(51,520)
Vested and issued	343,530
Outstanding at ending	29,980	49,129	81,352
Outstanding, shares at ending	912,560	936,267
Weighted-Average Grant Date Fair Value Per Share
Outstanding, beginning balance	$ 120.97
Granted, per Share	164.93	$ 133.65	$ 121.26
Forfeited, per Share	138.91
Vested and Issued, per Share	115.69
Outstanding, ending balance, per Share	$ 139.83	$ 120.97
Performance shares
Unvested shares
Outstanding, shares at beginning	259,532
Granted	113,166
Vested and issued	153,555
Outstanding, shares at ending	219,143	259,532
Weighted-Average Grant Date Fair Value Per Share
Outstanding, beginning balance	$ 113.68
Granted, per Share	138.29	$ 133.83	117.94
Vested and Issued, per Share	97.35
Outstanding, ending balance, per Share	$ 137.83	$ 113.68
Deferred share units
Unvested shares
Outstanding at beginning	30,481
Granted	3,746
Cash settled	(9,207)
Share settled	(4,602)
Outstanding at ending	20,418	30,481
Weighted-Average Grant Date Fair Value Per Share
Outstanding, beginning balance, per Share	$ 77.34
Granted, per Share	168.71	$ 136.47	$ 121
Cash Settled, per Share	61.65
Share Settled, per Share	94.15
Outstanding, ending balance, per Share	$ 97.38	$ 77.34
Progressive Waste Solutions Ltd. | Restricted stock units (RSUs)
Unvested shares
Outstanding at beginning	51,812
Cash settled	(6,346)
Outstanding at ending	45,466	51,812

Shareholders' Equity - Warrant

Shareholders' Equity - Warrant Activity Schedule (Details) - Stock Purchase Warrants	12 Months Ended
	Dec. 31, 2024 $ / shares shares
Instruments Other Than Options
Outstanding at beginning | shares	817,873
Granted | shares	301,719
Forfeited | shares	(153,306)
Exercised | shares	(44,860)
Outstanding at ending | shares	921,426
Weighed Average Exercise Price
Outstanding beginning balance | $ / shares	$ 127.85
Granted | $ / shares	171.51
Forfeited | $ / shares	133.59
Exercised | $ / shares	107.04
Outstanding ending balance | $ / shares	$ 142.21

Shareholders' Equity - Warrants

Shareholders' Equity - Warrants Outstanding Schedule (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Class of Warrant or Right [Line Items]
Outstanding, ending balance	921,426	817,873
Stock Purchase Warrants 2019 Issuance
Class of Warrant or Right [Line Items]
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	0	25,490
Stock Purchase Warrants 2020 Issuance
Class of Warrant or Right [Line Items]
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	85,293	145,586
Stock Purchase Warrants 2021 Issuance
Class of Warrant or Right [Line Items]
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	191,155	191,155
Stock Purchase Warrants 2022 Issuance
Class of Warrant or Right [Line Items]
Warrants issued	380,478
Exercise price, lower limit	$ 125.32
Exercise price, upper limit	$ 143.95
Fair value of warrants issued	$ 12,972
Outstanding, ending balance	289,276	326,085
Stock Purchase Warrants 2023 Issuance
Class of Warrant or Right [Line Items]
Warrants issued	129,557
Exercise price, lower limit	$ 129.75
Exercise price, upper limit	$ 142.93
Fair value of warrants issued	$ 5,133
Outstanding, ending balance	106,649	129,557
Stock Purchase Warrants 2024 Issuance
Class of Warrant or Right [Line Items]
Warrants issued	301,719
Exercise price, lower limit	$ 149.27
Exercise price, upper limit	$ 192.47
Fair value of warrants issued	$ 14,651
Outstanding, ending balance	249,053	0

Other Comprehensive Income (L_3

Other Comprehensive Income (Loss) - Components of Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest rate swap amounts reclassified into interest expense, Net of Tax	$ (15,043)	$ (14,411)	$ 4,815
Changes in fair value of interest rate swaps, Net of Tax	8,531	7,782	56,107
Foreign currency translation adjustment, Gross	(189,402)	53,633	(157,336)
Foreign currency translation adjustment, Net of Tax	(189,402)	53,633	(157,336)
Other comprehensive income (loss), before tax	(198,262)	44,614	(74,449)
Other Comprehensive Income (Loss), Tax	(2,348)	(2,390)	21,965
Other comprehensive income (loss), net of tax	(195,914)	47,004	(96,414)
Interest rate swap
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest rate swap amounts reclassified into interest expense, Gross	(20,467)	(19,607)	6,551
Interest rate swap amounts reclassified into interest expense, Tax Effect	5,424	5,196	(1,736)
Interest rate swap amounts reclassified into interest expense, Net of Tax	(15,043)	(14,411)	4,815
Changes in fair value of interest rate swaps	11,607	10,588	76,336
Changes in fair value of interest rate swaps, Tax Effect	(3,076)	(2,806)	(20,229)
Changes in fair value of interest rate swaps, Net of Tax	$ 8,531	$ 7,782	$ 56,107

Other Comprehensive Income (L_4

Other Comprehensive Income (Loss) - Amounts Included in AOCIL (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity Attributable to Parent, Beginning Balance	$ 7,692,809
Foreign currency translation adjustment	(189,402)	$ 53,633	$ (157,336)
Stockholders' Equity Attributable to Parent, Ending Balance	7,860,354	7,692,809
ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity Attributable to Parent, Beginning Balance	(9,826)	(56,830)
Amounts reclassified into earnings	(15,043)	(14,411)
Change in fair value	8,531	7,782
Foreign currency translation adjustment	(189,402)	53,633	(157,336)
Stockholders' Equity Attributable to Parent, Ending Balance	(205,740)	(9,826)	(56,830)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Interest rate swap
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity Attributable to Parent, Beginning Balance	16,749	23,378
Amounts reclassified into earnings	(15,043)	(14,411)
Change in fair value	8,531	7,782
Stockholders' Equity Attributable to Parent, Ending Balance	10,237	16,749	23,378
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Foreign Currency Translation Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity Attributable to Parent, Beginning Balance	(26,575)	(80,208)
Foreign currency translation adjustment	(189,402)	53,633
Stockholders' Equity Attributable to Parent, Ending Balance	$ (215,977)	$ (26,575)	$ (80,208)

INCOME TAXES - Narrative (Detai

INCOME TAXES - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
INCOME TAXES
Statutory income tax rate	21%	21%	21%
Unrecognized tax benefits	$ 0	$ 0	$ 0
Deferred tax liabilities, undistributed earnings	2,903,543
Deferred tax liability not recognized, undistributed earnings of foreign subsidiaries	401,204
Undistributed earnings	$ 4,078,543
Canada Revenue Agency
INCOME TAXES
Foreign Statutory income tax rate	27%
Operating loss carryforwards	$ 14,901

INCOME TAXES - Income (Loss) Be

INCOME TAXES - Income (Loss) Before Provision (Benefit) for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
INCOME TAXES
U.S.	$ 343,255	$ 622,041	$ 734,126
Non-U.S.	419,678	361,460	314,837
Income before income tax provision	$ 762,933	$ 983,501	$ 1,048,963

INCOME TAXES - Provision Benefi

INCOME TAXES - Provision Benefit for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Current:
U.S. Federal	$ 95,007	$ 120,420	$ 59,675
State	42,725	50,713	28,770
Non - U.S.	65,916	43,213	31,036
Current income tax expense (benefit), total	203,648	214,346	119,481
Deferred:
U.S. Federal	(33,507)	14,130	95,397
State	(5,833)	(1,931)	16,840
Non - U.S.	(17,945)	(5,870)	(18,756)
Deferred Income Tax Expense (Benefit), Total	(57,285)	6,329	93,481
Income Tax Expense (Benefit), Total	$ 146,363	$ 220,675	$ 212,962

INCOME TAXES - Differences betw

INCOME TAXES - Differences between Income Tax Provision in Statements of Net Income and Income Tax Provision Computed at Federal Statutory Rate (Details)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
INCOME TAXES
U.S. federal statutory rate	21%	21%	21%
State taxes, net of federal benefit	4.10%	4.30%	4.20%
Deferred income tax liability adjustments	0.70%	0.30%
Effect of international operations	(3.80%)	(3.90%)	(4.00%)
Federal tax credits	(1.50%)		(0.10%)
Share-based compensation	(0.70%)	(0.30%)	(0.20%)
Other	(0.60%)	1%	(0.60%)
Effective income tax rate, total	19.20%	22.40%	20.30%

INCOME TAXES - Significant Comp

INCOME TAXES - Significant Components of Deferred Income Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Deferred income tax assets:
Accrued expenses	$ 38,674	$ 33,358
Compensation	26,589	25,781
Contingent liabilities	16,237	27,154
Tax credits and loss carryforwards	15,477	23,877
Landfill closure and post-closure	90,240	12,476
Finance costs	4,032	6,968
Other	13,306	14,036
Gross deferred income tax assets	204,555	143,650
Less: Valuation allowance
Total deferred income tax assets	204,555	143,650
Deferred income tax liabilities:
Goodwill and other intangibles	(472,608)	(471,074)
Property and equipment	(595,156)	(602,453)
Prepaid expenses	(19,737)	(15,428)
Interest rate swaps	(3,691)	(6,039)
Investment in subsidiaries	(71,703)	(71,136)
Total deferred income tax liabilities	(1,162,895)	(1,166,130)
Net deferred income tax liability	$ (958,340)	$ (1,022,480)

SEGMENT REPORTING - Narrative (

SEGMENT REPORTING - Narrative (Details) - segment	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
SEGMENT REPORTING
Number of contracts or customers accounted for more than 10% of the Company's total revenues at the consolidated or reportable segment level	No single contract or customer accounted for more than 10% of the Company’s total revenues at the consolidated or reportable segment level during the periods presented
Number of operating segments	6
Number of reportable segments	6	6	6

SEGMENT REPORTING - Summary of

SEGMENT REPORTING - Summary of Financial Information of Reportable Segments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
SEGMENT REPORTING
Revenue	$ 8,919,591	$ 8,021,951	$ 7,211,859
Segment expenses	(6,075,151)	(5,543,632)	(5,032,479)
Segment EBITDA	$ 2,844,440	$ 2,478,319	$ 2,179,380
Segment EBITDA margin	31.90%	30.90%	30.20%
Depreciation and amortization	$ (1,163,769)	$ (1,003,211)	$ (918,960)
Other segment items	(917,738)	(491,607)	(211,457)
Income before income tax provision	762,933	983,501	1,048,963
Capital expenditures	1,055,988	934,000	912,677
Total assets	19,817,809	17,915,876	17,134,603
Intercompany Revenue
SEGMENT REPORTING
Revenue	(1,275,398)	(1,145,781)	(998,069)
Reportable Segments
SEGMENT REPORTING
Revenue	10,194,989	9,167,732	8,209,928
Corporate
SEGMENT REPORTING
Segment expenses	(27,655)	(25,032)	(25,019)
Segment EBITDA	(27,655)	(25,032)	(25,019)
Depreciation and amortization	(9,378)	(7,835)	(8,835)
Other segment items	(309,876)	(325,215)	(199,879)
Capital expenditures	22,636	18,556	5,877
Total assets	462,046	442,159	426,542
Western
SEGMENT REPORTING
Revenue	1,798,669	1,669,289	1,428,031
Western | Intercompany Revenue
SEGMENT REPORTING
Revenue	(235,701)	(209,554)	(177,543)
Western | Reportable Segments
SEGMENT REPORTING
Revenue	2,034,370	1,878,843	1,605,574
Segment expenses	(1,277,911)	(1,186,084)	(1,003,096)
Segment EBITDA	$ 520,758	$ 483,205	$ 424,935
Segment EBITDA margin	29%	28.90%	29.80%
Depreciation and amortization	$ (211,111)	$ (199,426)	$ (155,882)
Other segment items	(596,463)	(160,351)	(738)
Capital expenditures	198,849	192,148	232,714
Total assets	3,512,253	3,432,529	3,239,679
Southern
SEGMENT REPORTING
Revenue	1,757,193	1,642,274	1,494,439
Southern | Intercompany Revenue
SEGMENT REPORTING
Revenue	(226,957)	(204,439)	(176,425)
Southern | Reportable Segments
SEGMENT REPORTING
Revenue	1,984,150	1,846,713	1,670,864
Segment expenses	(1,200,768)	(1,124,272)	(1,027,920)
Segment EBITDA	$ 556,425	$ 518,002	$ 466,519
Segment EBITDA margin	31.70%	31.50%	31.20%
Depreciation and amortization	$ (203,445)	$ (179,948)	$ (175,614)
Other segment items	(9,395)	(11,165)	(7,330)
Capital expenditures	190,912	166,961	151,093
Total assets	3,885,522	3,501,953	3,410,888
Eastern
SEGMENT REPORTING
Revenue	1,564,211	1,380,233	1,233,695
Eastern | Intercompany Revenue
SEGMENT REPORTING
Revenue	(311,348)	(259,118)	(211,498)
Eastern | Reportable Segments
SEGMENT REPORTING
Revenue	1,875,559	1,639,351	1,445,193
Segment expenses	(1,146,988)	(1,027,172)	(952,173)
Segment EBITDA	$ 417,223	$ 353,061	$ 281,522
Segment EBITDA margin	26.70%	25.60%	22.80%
Depreciation and amortization	$ (230,466)	$ (207,909)	$ (190,480)
Other segment items	(4,398)	(2,492)	(4,154)
Capital expenditures	191,817	143,484	138,028
Total assets	3,544,234	3,228,244	2,752,436
Central
SEGMENT REPORTING
Revenue	1,514,902	1,440,157	1,288,348
Central | Intercompany Revenue
SEGMENT REPORTING
Revenue	(181,657)	(180,751)	(159,355)
Central | Reportable Segments
SEGMENT REPORTING
Revenue	1,696,559	1,620,908	1,447,703
Segment expenses	(972,101)	(927,874)	(842,033)
Segment EBITDA	$ 542,801	$ 512,283	$ 446,315
Segment EBITDA margin	35.80%	35.60%	34.60%
Depreciation and amortization	$ (170,424)	$ (169,370)	$ (156,895)
Other segment items	1,483	6,763	5,368
Capital expenditures	174,805	171,748	181,065
Total assets	2,827,108	2,811,016	2,803,853
Canada
SEGMENT REPORTING
Revenue	1,260,980	995,842	940,624
Canada | Intercompany Revenue
SEGMENT REPORTING
Revenue	(124,889)	(113,322)	(107,048)
Canada | Reportable Segments
SEGMENT REPORTING
Revenue	1,385,869	1,109,164	1,047,672
Segment expenses	(709,501)	(605,178)	(591,221)
Segment EBITDA	$ 551,479	$ 390,664	$ 349,403
Segment EBITDA margin	43.70%	39.20%	37.10%
Depreciation and amortization	$ (200,274)	$ (121,326)	$ (118,388)
Other segment items	944	(2,930)	(1,118)
Capital expenditures	147,596	105,453	70,051
Total assets	3,564,052	2,794,795	2,773,882
MidSouth
SEGMENT REPORTING
Revenue	1,023,636	894,156	826,722
MidSouth | Intercompany Revenue
SEGMENT REPORTING
Revenue	(194,846)	(178,597)	(166,200)
MidSouth | Reportable Segments
SEGMENT REPORTING
Revenue	1,218,482	1,072,753	992,922
Segment expenses	(740,227)	(648,020)	(591,017)
Segment EBITDA	$ 283,409	$ 246,136	$ 235,705
Segment EBITDA margin	27.70%	27.50%	28.50%
Depreciation and amortization	$ (138,671)	$ (117,397)	$ (112,866)
Other segment items	(33)	3,783	(3,606)
Capital expenditures	129,373	135,650	133,849
Total assets	$ 2,022,594	$ 1,705,180	$ 1,727,323

SEGMENT REPORTING - Changes in

SEGMENT REPORTING - Changes in Goodwill by Reportable Segment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
SEGMENT REPORTING
Goodwill, Beginning Balance	$ 7,404,400	$ 6,902,297
Goodwill acquired	699,514	465,136
Goodwill acquisition adjustments		(2,215)
Goodwill divested		(1,431)
Impact of changes in foreign currency	(153,508)	40,613
Goodwill, Ending Balance	7,950,406	7,404,400
Western | Reportable Segments
SEGMENT REPORTING
Goodwill, Beginning Balance	779,455	732,335
Goodwill acquired	85,147	47,120
Goodwill, Ending Balance	864,602	779,455
Southern | Reportable Segments
SEGMENT REPORTING
Goodwill, Beginning Balance	1,559,703	1,547,894
Goodwill acquired	17,411	11,809
Goodwill, Ending Balance	1,577,114	1,559,703
Eastern | Reportable Segments
SEGMENT REPORTING
Goodwill, Beginning Balance	1,587,491	1,189,111
Goodwill acquired	148,093	398,380
Goodwill, Ending Balance	1,735,584	1,587,491
Central | Reportable Segments
SEGMENT REPORTING
Goodwill, Beginning Balance	1,008,500	1,003,470
Goodwill acquired	2,074	6,461
Goodwill divested		(1,431)
Goodwill, Ending Balance	1,010,574	1,008,500
Canada | Reportable Segments
SEGMENT REPORTING
Goodwill, Beginning Balance	1,723,068	1,684,670
Goodwill acquired	343,531
Goodwill acquisition adjustments		(2,215)
Impact of changes in foreign currency	(153,508)	40,613
Goodwill, Ending Balance	1,913,091	1,723,068
MidSouth | Reportable Segments
SEGMENT REPORTING
Goodwill, Beginning Balance	746,183	744,817
Goodwill acquired	103,258	1,366
Goodwill, Ending Balance	$ 849,441	$ 746,183

SEGMENT REPORTING - Property an

SEGMENT REPORTING - Property and Equipment in US and Canada (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
SEGMENT REPORTING
Property and equipment	$ 8,035,929	$ 7,228,331
United States
SEGMENT REPORTING
Property and equipment	6,870,901	6,456,319
Canada
SEGMENT REPORTING
Property and equipment	$ 1,165,028	$ 772,012

SEGMENT REPORTING - Reconciliat

SEGMENT REPORTING - Reconciliation of Segment EBITDA to Income Before Income Tax Provision (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
SEGMENT REPORTING
Segment EBITDA	$ 2,844,440	$ 2,478,319	$ 2,179,380
Depreciation	(974,001)	(845,638)	(763,285)
Amortization of intangibles	(189,768)	(157,573)	(155,675)
Impairments and other operating items	(613,012)	(238,796)	(18,230)
Interest expense	(326,804)	(274,642)	(202,331)
Interest income	11,607	9,350	5,950
Other income, net	10,471	12,481	3,154
Income before income tax provision	762,933	983,501	1,048,963
Corporate
SEGMENT REPORTING
Segment EBITDA	(27,655)	(25,032)	(25,019)
Western | Reportable Segments
SEGMENT REPORTING
Segment EBITDA	520,758	483,205	424,935
Southern | Reportable Segments
SEGMENT REPORTING
Segment EBITDA	556,425	518,002	466,519
Eastern | Reportable Segments
SEGMENT REPORTING
Segment EBITDA	417,223	353,061	281,522
Central | Reportable Segments
SEGMENT REPORTING
Segment EBITDA	542,801	512,283	446,315
Canada | Reportable Segments
SEGMENT REPORTING
Segment EBITDA	551,479	390,664	349,403
MidSouth | Reportable Segments
SEGMENT REPORTING
Segment EBITDA	$ 283,409	$ 246,136	$ 235,705

Net Income Per Share Informat_3

Net Income Per Share Information - Basic and Diluted Net Income Per Common Share (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Numerator:
Net income attributable to Waste Connections for basic and diluted earnings per share	$ 617,573	$ 762,800	$ 835,662
Denominator:
Basic shares outstanding	257,965,871	257,551,129	257,383,578
Dilutive effect of equity-based awards	696,319	598,115	655,223
Diluted shares outstanding	258,662,190	258,149,244	258,038,801

Employee Benefit Plans - Narrat

Employee Benefit Plans - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($) agreement	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Multiemployer Plan [Line Items]
Percentage of every dollar of a participating employee's pre-tax contributions as matching contribution to 401(k) Plan	100%
Number of multiemployer pension plans | agreement	16
Deferred Compensation Plan
Multiemployer Plan [Line Items]
Percentage of every dollar of a participating employee's pre-tax contributions as matching contribution to 401(k) Plan	100%	100%	100%
Percentage of employee's eligible compensation that represents the maximum amount of employer matching contribution to plan	5%	5%	5%
Percentage of salary that may voluntarily be elected to be deferred	80%
Percentage of bonuses, commissions and restricted share unit grants that may voluntarily be elected to be deferred	100%
Total liability for deferred compensation	$ 36,006	$ 42,270
Voluntary Savings And Investment Plan
Multiemployer Plan [Line Items]
Total employer expenses, including employer matching contributions	$ 46,489	$ 42,100	$ 37,165
Maximum
Multiemployer Plan [Line Items]
Percentage of employee's eligible compensation that represents the maximum amount of employer matching contribution to plan	5%
Maximum | Retirement Savings Plan
Multiemployer Plan [Line Items]
Contribution to a deferred profit sharing plan	5%

Employee Benefit Plans - Plan C

Employee Benefit Plans - Plan Contributions (Details) - USD ($) $ in Thousands			3 Months Ended	9 Months Ended		12 Months Ended
	Apr. 30, 2022	Jan. 01, 2022	Jun. 30, 2023	Dec. 31, 2024	Mar. 31, 2024	Dec. 31, 2024	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Dec. 31, 2022
Multiemployer Plan [Line Items]
Company Contributions						$ 23,158		$ 20,994		$ 17,156
Western Conference of Teamsters Pension Trust
Multiemployer Plan [Line Items]
EIN/Pension Plan Number/Registration Number						91-6145047 - 001
Pension Protection Act Zone Status						Green		Green
FIP/RP Status						NA
Company Contributions						$ 9,676		$ 8,747		5,803
Western Conference of Teamsters Pension Trust | Minimum
Multiemployer Plan [Line Items]
Expiration Date of Collective Bargaining Agreement						Dec. 31, 2024
Western Conference of Teamsters Pension Trust | Maximum
Multiemployer Plan [Line Items]
Expiration Date of Collective Bargaining Agreement						Jun. 30, 2028
Local 731, I.B. of T., Pension Fund
Multiemployer Plan [Line Items]
EIN/Pension Plan Number/Registration Number						36-6513567 - 001
Pension Protection Act Zone Status							Green		Green
FIP/RP Status						NA
Company Contributions						$ 5,471		$ 4,939		4,484
Expiration Date of Collective Bargaining Agreement						Sep. 30, 2028
Suburban Teamsters of Northern Illinois Pension Fund
Multiemployer Plan [Line Items]
EIN/Pension Plan Number/Registration Number						36-6155778 - 001
Pension Protection Act Zone Status						Green		Green
FIP/RP Status						NA
Company Contributions						$ 3,013		$ 2,671		2,516
Expiration Date of Collective Bargaining Agreement						Feb. 28, 2029
Teamster Local 301 Pension Fund
Multiemployer Plan [Line Items]
EIN/Pension Plan Number/Registration Number						36-6492992 - 001
Pension Protection Act Zone Status						Green		Green
FIP/RP Status						NA
Company Contributions						$ 1,314		$ 1,183		1,310
Expiration Date of Collective Bargaining Agreement						Sep. 30, 2028
Midwest Operating Engineers Pension Plan
Multiemployer Plan [Line Items]
EIN/Pension Plan Number/Registration Number						36-6140097 - 001
Pension Protection Act Zone Status			Green	Green	Green
FIP/RP Status						NA
Company Contributions						$ 774		$ 704		542
Expiration Date of Collective Bargaining Agreement						Oct. 31, 2025
Automobile Mechanics' Local No. 701 Union and Industry Pension Fund
Multiemployer Plan [Line Items]
EIN/Pension Plan Number/Registration Number						36-6042061 - 001
Pension Protection Act Zone Status						Green		Green
FIP/RP Status						NA
Company Contributions						$ 562		$ 452		470
Expiration Date of Collective Bargaining Agreement						Dec. 31, 2025
Local 813 Pension Trust Fund
Multiemployer Plan [Line Items]
EIN/Pension Plan Number/Registration Number						13-1975659 - 001
Pension Protection Act Zone Status						Red		Red
FIP/RP Status						Implemented
Company Contributions						$ 485		$ 557		429
Expiration Date of Collective Bargaining Agreement						Nov. 30, 2027
IAM National Pension Fund
Multiemployer Plan [Line Items]
EIN/Pension Plan Number/Registration Number						51-6031295 - 002
Pension Protection Act Zone Status						Red		Red
FIP/RP Status						Implemented
Company Contributions						$ 469		$ 442		342
Expiration Date of Collective Bargaining Agreement						Dec. 31, 2025
Locals 302 & 612 of the IOUE - Employers Construction Industry Retirement Plan
Multiemployer Plan [Line Items]
EIN/Pension Plan Number/Registration Number						91-6028571 - 001
Pension Protection Act Zone Status						Green		Green
FIP/RP Status						NA
Company Contributions						$ 355		$ 341		338
Expiration Date of Collective Bargaining Agreement						Nov. 30, 2026
International Union of Operating Engineers Pension Trust
Multiemployer Plan [Line Items]
EIN/Pension Plan Number/Registration Number						85512-1
Pension Protection Act Zone Status	Green
FIP/RP Status						NA
Company Contributions						$ 296		285		281
International Union of Operating Engineers Pension Trust | Minimum
Multiemployer Plan [Line Items]
Expiration Date of Collective Bargaining Agreement						Mar. 31, 2025
International Union of Operating Engineers Pension Trust | Maximum
Multiemployer Plan [Line Items]
Expiration Date of Collective Bargaining Agreement						Mar. 31, 2028
Multi-Sector Pension Plan
Multiemployer Plan [Line Items]
EIN/Pension Plan Number/Registration Number						1085653
Pension Protection Act Zone Status		Red
FIP/RP Status						NA
Company Contributions						$ 274		$ 246		249
Expiration Date of Collective Bargaining Agreement						Dec. 31, 2026
Recycling and General Industrial Union Local 108 Pension Fund
Multiemployer Plan [Line Items]
EIN/Pension Plan Number/Registration Number						13-6366378 - 001
Pension Protection Act Zone Status						Green		Green
FIP/RP Status						NA
Company Contributions						$ 246		$ 225		230
Expiration Date of Collective Bargaining Agreement						Feb. 28, 2027
Nurses and Local 813 IBT Retirement Plan
Multiemployer Plan [Line Items]
EIN/Pension Plan Number/Registration Number						13-3628926 - 001
Pension Protection Act Zone Status						Green		Green
FIP/RP Status						NA
Company Contributions						$ 125		$ 121		97
Expiration Date of Collective Bargaining Agreement						Nov. 30, 2027
Contributions to other multiemployer plans
Multiemployer Plan [Line Items]
Company Contributions						$ 98		$ 81		$ 65

Subsequent Event (Details)

Subsequent Event (Details) - Q1 2025 Dividend - Subsequent Event - $ / shares		1 Months Ended
	Feb. 12, 2025	Feb. 12, 2025
Subsequent Event [Line Items]
Dividends, declared date	Feb. 12, 2025
Dividends per share amount		$ 0.315
Dividends, date to be paid	Mar. 13, 2025
Dividends, date of record	Feb. 27, 2025

SCHEDULE II - Valuation and Q_2

SCHEDULE II - Valuation and Qualifying Accounts (Details) - SEC Schedule, 12-09, Allowance, Credit Loss [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation allowances and reserves, balance	$ 23,553	$ 22,939	$ 18,480
Valuation allowances and reserves, charged to cost and expense	20,063	17,504	17,259
Valuation allowances and reserves, deductions	(17,886)	(16,890)	(12,800)
Valuation allowances and reserves, balance	$ 25,730	$ 23,553	$ 22,939