Waste Connections (WCN) 10-K 13 Feb 20 2019 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2019	Feb. 03, 2020	Jun. 30, 2019
Document Document and Entity Information [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2019
Document Transition Report	false
Entity File Number	1-34370
Entity Registrant Name	WASTE CONNECTIONS, INC.
Entity Incorporation, State or Country Code	A6
Entity Tax Identification Number	98-1202763
Entity Address, Address Line One	610 Applewood Crescent, 2nd Floor
Entity Address, City or Town	Vaughan
Entity Address, State or Province	ON
Entity Address, Country	CA
Entity Address, Postal Zip Code	L4K 0E3
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
Entity Shell Company	false
Entity Public Float			$ 25,124,471,729
Entity Common Stock, Shares Outstanding		263,689,637
Entity Central Index Key	0001318220
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2019
Amendment Flag	false

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and equivalents	$ 326,738	$ 319,305
Accounts receivable, net of allowance for doubtful accounts of $16,432 and $16,760 at December 31, 2019 and 2018, respectively	662,808	609,545
Prepaid expenses and other current assets	141,052	164,053
Total current assets	1,130,598	1,092,903
Restricted cash	96,483	84,661
Restricted investments	51,179	47,486
Property and equipment, net	5,516,347	5,168,996
Operating lease, right-of-use asset	183,220
Goodwill	5,510,851	5,031,685
Intangible assets, net	1,163,063	1,128,628
Other assets, net	85,954	72,970
Total assets	13,737,695	12,627,329
Current liabilities:
Accounts payable	436,970	359,967
Book overdraft	15,954	18,518
Accrued liabilities	281,308	315,670
Current portion of operating lease liabilities	29,929
Current portion of contingent consideration	26,159	11,612
Deferred revenue	216,443	179,282
Current portion of long-term debt and notes payable	465	1,786
Total current liabilities	1,007,228	886,835
Long-term debt and notes payable	4,353,782	4,153,465
Long-term portion of operating lease liabilities	160,033
Long-term portion of contingent consideration	42,825	43,003
Deferred income taxes	818,622	760,033
Other long-term liabilities	416,851	323,805
Total liabilities	6,799,341	6,167,141
Commitments and contingencies (Note 12)
Equity:
Common shares: 263,699,675 shares issued and 263,618,161 shares outstanding at December 31, 2019; 263,271,302 shares issued and 263,141,413 shares outstanding at December 31, 2018	4,135,343	4,131,307
Additional paid-in capital	154,917	133,577
Accumulated other comprehensive income (loss)	(10,963)	(74,786)
Treasury shares: 81,514 and 129,889 shares at December 31, 2019 and 2018, respectively
Retained earnings	2,654,207	2,264,510
Total Waste Connections' equity	6,933,504	6,454,608
Noncontrolling interest in subsidiaries	4,850	5,580
Total equity	6,938,354	6,460,188
Total liabilities and shareholders' equity	$ 13,737,695	$ 12,627,329

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts	$ 16,432	$ 16,760
Common shares, shares issued	263,699,675	263,271,302
Common shares, shares outstanding	263,618,161	263,141,413
Treasury shares	81,514	129,889

Condensed Consolidated Statemen

Condensed Consolidated Statements of Net Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Statement [Abstract]
Revenues	$ 5,388,679	$ 4,922,941	$ 4,630,488
Operating expenses:
Cost of operations	3,198,757	2,865,704	2,704,775
Selling, general and administrative	546,278	524,388	509,638
Depreciation	618,396	572,708	530,187
Amortization of intangibles	125,522	107,779	102,297
Impairments and other operating items	61,948	20,118	156,493
Operating income	837,778	832,244	627,098
Interest expense	(147,368)	(132,104)	(125,297)
Interest income	9,777	7,170	5,173
Other income (expense), net	5,704	(170)	1,536
Income before income tax provision	705,891	707,140	508,510
Income tax (provision) benefit	(139,210)	(159,986)	68,910
Net income	566,681	547,154	577,420
Less: Net income attributable to noncontrolling interests	160	(283)	(603)
Net income attributable to Waste Connections	$ 566,841	$ 546,871	$ 576,817
Earnings per common share attributable to Waste Connections' common stockholders:
Basic	$ 2.15	$ 2.07	$ 2.19
Diluted	$ 2.14	$ 2.07	$ 2.18
Shares used in the per share calculations:
Basic	263,792,693	263,650,155	263,682,608
Diluted	264,526,561	264,395,618	264,302,411
Cash dividends per common share	$ 0.665	$ 0.580	$ 0.500

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Net income	$ 566,681	$ 547,154	$ 577,420
Other comprehensive income (loss), before tax:
Foreign currency translation adjustment	101,970	(175,233)	142,486
Other comprehensive income (loss), before tax	50,070	(185,995)	157,270
Income tax (expense) benefit related to items of other comprehensive income (loss)	13,753	2,796	(5,856)
Other comprehensive income (loss), net of tax	63,823	(183,199)	151,414
Comprehensive income	630,504	363,955	728,834
Less: Comprehensive income attributable to noncontrolling interests	160	(283)	(603)
Comprehensive income attributable to Waste Connections	630,664	363,672	728,231
Interest Rate Swap [Member]
Other comprehensive income (loss), before tax:
Amounts reclassified, gross	(8,027)	(5,669)	2,805
Change in fair value, gross	$ (43,873)	(1,213)	7,835
Fuel [Member] | Commodity Contract [Member]
Other comprehensive income (loss), before tax:
Amounts reclassified, gross		(6,531)	2,818
Change in fair value, gross		$ 2,651	$ 1,326

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Equity - USD ($) $ in Thousands	Deferred Compensation Plan [Member]Common Stock [Member]	Performance Shares [Member]Common Stock [Member]	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]	Retained Earnings [Member]	Noncontrolling Interests [Member]	Total
Beginning Balances at Dec. 31, 2016			$ 4,174,808	$ 102,220	$ (43,001)		$ 1,413,488	$ 7,362	$ 5,654,877
Beginning Balances, shares at Dec. 31, 2016			262,803,271
Beginning Balance, treasury shares at Dec. 31, 2016						337,397
Sale of common shares held in trust			$ 10,814						10,814
Sale of common shares held in trust, shares			171,264			(171,264)
Vesting of restricted share units (shares)	37,263	122,786	545,238
Tax withholdings related to net share settlements of equity-based compensation				(13,994)					(13,994)
Tax withholdings related to net share settlements of equity-based compensation, shares			(251,738)
Equity-based compensation				25,435					25,435
Exercise of stock options and warrants			$ 1,946						$ 1,946
Exercise of stock options and warrants, shares			66,586
Repurchase of common shares, shares									0
Cash dividends on common shares							(131,975)		$ (131,975)
Amounts reclassified into earnings, net of taxes					4,174				4,174
Changes in fair value of cash flow hedges, net of taxes					4,754				4,754
Foreign currency translation adjustment					142,486				142,486
Acquisition of noncontrolling interest				698				(2,565)	(1,867)
Net income							576,817	603	577,420
Ending Balances at Dec. 31, 2017			$ 4,187,568	115,743	108,413		1,856,946	5,400	6,274,070
Ending Balances, Shares at Dec. 31, 2017			263,494,670
Ending Balance, treasury shares at Dec. 31, 2017						166,133
Cumulative effect adjustment from adoption of new accounting pronouncement				1,384			1,384
Sale of common shares held in trust			$ 2,667						2,667
Sale of common shares held in trust, shares			36,244			(36,244)
Vesting of restricted share units (shares)	5,069	154,181	483,232
Fair value adjustment for common shares in deferred compensation plan exchanged for other investment options				(1,734)					(1,734)
Tax withholdings related to net share settlements of equity-based compensation				(15,032)					(15,032)
Tax withholdings related to net share settlements of equity-based compensation, shares			(217,850)
Equity-based compensation				34,600					34,600
Exercise of warrants, shares			17,571
Repurchase of common shares			$ (58,928)						$ (58,928)
Repurchase of common shares, shares			(831,704)						(831,704)
Cash dividends on common shares							(152,550)		$ (152,550)
Amounts reclassified into earnings, net of taxes					(9,071)				(9,071)
Changes in fair value of cash flow hedges, net of taxes					1,105				1,105
Foreign currency translation adjustment					(175,233)				(175,233)
Distributions to noncontrolling interests								(103)	(103)
Net income							546,871	283	547,154
Ending Balances at Dec. 31, 2018			$ 4,131,307	133,577	(74,786)		2,264,510	5,580	$ 6,460,188
Ending Balances, Shares at Dec. 31, 2018			263,141,413						263,141,413
Ending Balance, treasury shares at Dec. 31, 2018						129,889			129,889
Cumulative effect adjustment from adoption of new accounting pronouncement							13,243		$ 13,243
Sale of common shares held in trust			$ 4,036						4,036
Sale of common shares held in trust, shares			48,375			(48,375)
Vesting of restricted share units (shares)	16,375	180,258	416,691
Tax withholdings related to net share settlements of equity-based compensation				(17,660)					(17,660)
Tax withholdings related to net share settlements of equity-based compensation, shares			(210,018)
Equity-based compensation				39,000					$ 39,000
Exercise of stock options and warrants, shares			25,067
Repurchase of common shares, shares									0
Cash dividends on common shares							(175,067)		$ (175,067)
Amounts reclassified into earnings, net of taxes					(5,900)				(5,900)
Changes in fair value of cash flow hedges, net of taxes					(32,247)				(32,247)
Foreign currency translation adjustment					101,970				101,970
Distributions to noncontrolling interests								(570)	(570)
Net income							566,841	(160)	566,681
Ending Balances at Dec. 31, 2019			$ 4,135,343	$ 154,917	$ (10,963)		2,654,207	$ 4,850	$ 6,938,354
Ending Balances, Shares at Dec. 31, 2019			263,618,161						263,618,161
Ending Balance, treasury shares at Dec. 31, 2019						81,514			81,514
Cumulative effect adjustment from adoption of new accounting pronouncement							$ (2,077)		$ (2,077)

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities:
Net income	$ 566,681	$ 547,154	$ 577,420
Adjustments to reconcile net income to net cash provided by operating activities:
Loss on disposal of assets and impairments	60,592	10,193	134,491
Depreciation	618,396	572,708	530,187
Amortization of intangibles	125,522	107,779	102,297
Amortization of leases	24,099
Deferred income taxes, net of acquisitions	54,637	77,859	(153,283)
Amortization of debt issuance costs	5,001	4,158	4,341
Share-based compensation	42,671	43,803	39,361
Interest accretion	16,426	14,861	13,822
Payment of contingent consideration recorded in earnings		(11)	(10,012)
Adjustments to contingent consideration	1,498	349	17,754
Other	(2,240)	943	1,611
Changes in operating assets and liabilities, net of effects from acquisitions:
Accounts receivable, net	(22,933)	(37,724)	(38,934)
Prepaid expenses and other current assets	9,135	39,758	(51,457)
Accounts payable	71,147	16,135	50,012
Deferred revenue	19,156	17,916	4,205
Accrued liabilities	(24,039)	1,314	(15,002)
Capping, closure and post-closure expenditures	(5,062)	(2,702)	(8,845)
Other long-term liabilities	(20,140)	(3,258)	(10,708)
Net cash provided by operating activities	1,540,547	1,411,235	1,187,260
Cash flows from investing activities:
Payments for acquisitions, net of cash acquired	(736,610)	(830,091)	(410,695)
Capital expenditures for property and equipment	(634,406)	(546,145)	(479,287)
Capital expenditure for purchase of greenfield landfill site	(31,683)
Investment in noncontrolling interest	(25,000)
Proceeds from disposal of assets	3,566	5,385	28,432
Change in restricted investments, net of interest income	(2,183)
Other	310	(969)	636
Net cash used in investing activities	(1,426,006)	(1,371,820)	(860,914)
Cash flows from financing activities:
Proceeds from long-term debt	1,575,795	1,022,737	973,754
Principal payments on notes payable and long-term debt	(1,470,711)	(970,773)	(770,106)
Payment of contingent consideration recorded at acquisition date	(3,200)	(6,127)	(17,158)
Change in book overdraft	(2,564)	(839)	8,241
Payments for repurchase of common shares		(58,928)
Payments for cash dividends	(175,067)	(152,550)	(131,975)
Tax withholdings related to net share settlements of equity-based compensation	(17,660)	(15,032)	(13,994)
Debt issuance costs	(5,953)	(8,630)	(3,667)
Proceeds from sale of common shares held in trust	4,036	2,667	10,814
Other	(570)	(103)	851
Net cash provided by (used in) financing activities	(95,894)	(187,578)	56,760
Effect of exchange rate changes on cash, cash equivalents and restricted cash	608	(1,290)	1,795
Net increase (decrease) in cash, cash equivalents and restricted cash	19,255	(149,453)	384,901
Cash, cash equivalents and restricted cash at beginning of year	403,966	553,227	168,476
Plus (less): change in cash held for sale		192	(150)
Cash, cash equivalents and restricted cash at end of year	423,221	403,966	553,227
SUPPLEMENTARY DISCLOSURES OF CASH FLOW INFORMATION AND NON-CASH TRANSACTIONS:
Cash paid for income taxes	81,049	52,464	155,532
Cash paid for interest	139,694	124,338	115,645
Changes in accrued capital expenditures for property and equipment	(7,528)	1,825	10,447
In connection with its acquisitions, the Company assumed liabilities as follows:
Fair value of assets acquired	910,177	1,100,880	635,361
Fair value of operations exchanged			(81,097)
Payments for acquisitions, net of cash acquired	(736,610)	(830,091)	(410,695)
Working capital settlements receivable	(5,272)	8,507
Liabilities assumed and notes payable issued to sellers of businesses acquired	$ 168,295	$ 279,296	143,569
Non-cash consideration received for asset sales			$ 12,573

Business

Business	12 Months Ended
	Dec. 31, 2019
Business [Abstract]
Business	1. BUSINESS The financial statements presented in this report represent the consolidation of Waste Connections, Inc., a corporation organized under the laws of Ontario, Canada, and its wholly-owned and majority-owned subsidiaries. When the terms the “Company” or “Waste Connections” are used in this document, those terms refer to Waste Connections, Inc. and its consolidated subsidiaries. All significant intercompany accounts and transactions have been eliminated in consolidation. The Company is an integrated solid waste services company that provides non-hazardous waste collection, transfer, disposal and recycling services in mostly exclusive and secondary markets in the U.S. and Canada. Through its R360 Environmental Solutions subsidiary, the Company is also a leading provider of non-hazardous exploration and production (“E&P”) waste treatment, recovery and disposal services in several of the most active natural resource producing areas in the U.S. The Company also provides intermodal services for the rail haul movement of cargo and solid waste containers in the Pacific Northwest through a network of intermodal facilities.

New Accounting Standards and Re

New Accounting Standards and Reclassifications	12 Months Ended
	Dec. 31, 2019
New Accounting Standards and Reclassifications [Abstract]
New Accounting Standards and Reclassifications	2. NEW ACCOUNTING STANDARDS AND RECLASSIFICATIONS Accounting Standards Adopted Lease Accounting The Company adopted the new standard on January 1, 2019 and elected to apply the new guidance at the effective date and recognize a cumulative-effect adjustment, without adjusting the comparative periods presented. The Company applied the package of practical expedients to leases that commenced before the effective date whereby the Company elected not to reassess the following: (1) whether any expired or existing contracts are or contain leases; (2) the lease classification for any expired or existing leases; and (3) whether initial direct costs exist for any existing leases. The Company also applied the (1) practical expedient for land easements where the Company elected to not apply the leases standard to certain existing land easements at transition and (2) practical expedient to include both the lease and nonlease components as a single component and account for it as a lease. The Company has completed its assessment of the provisions of the lease accounting guidance and implementation of its leasing software solution to manage and account for leases under the new standard. ​ ​ ​ ​ As Reported ​ Adoption of Lease Guidance ​ Balance Operating lease right-of-use assets $ - ​ $ 206,501 ​ $ 206,501 Total assets $ 12,627,329 ​ $ 206,501 ​ $ 12,833,830 Current portion of operating lease liabilities $ - ​ $ 29,640 ​ $ 29,640 Total current liabilities $ 886,835 ​ $ 29,640 ​ $ 916,475 Long-term portion of operating lease liabilities $ - ​ $ 180,005 ​ $ 180,005 Deferred income taxes $ 760,033 ​ $ (1,066) ​ $ 758,967 Total liabilities $ 6,167,141 ​ $ 208,579 ​ $ 6,375,720 Retained earnings $ 2,264,510 ​ $ (2,077) ​ $ 2,262,433 Total liabilities and equity $ 12,627,329 ​ $ 206,501 ​ $ 12,833,830 ​ The adoption of the new standard did not have a material impact on the Company’s consolidated statements of net income or consolidated statements of cash flows. See Note 8 for additional information and disclosures related to the adoption of this amended guidance. Derivatives and Hedging: Targeted Improvements to Accounting for Hedging Activities Derivatives and Hedging: Inclusion of the Secured Overnight Financing Rate (“SOFR”) Overnight Index Swap (“OIS”) Rate as a Benchmark Interest Rate for Hedge Accounting SEC modernizes and simplifies certain Regulation S-K disclosure requirements providing three years of financial statements to omit discussion of the earliest year and cross-reference its discussion in a previous filing; (3) removing the example risk factors in Regulation S-K to encourage more meaningful company-specific disclosure; (4) clarifying the description of property requirements to emphasize that those disclosures should only include properties that are material to the registrant; and (5) requiring XBRL data tagging for items on the cover pages of certain filings, as well as the use of hyperlinks for information that is incorporated by reference and available on EDGAR. The provisions regarding the redaction of confidential information in exhibits were effective upon publication in the Federal Register. The provisions requiring XBRL data tagging are subject to a three-year phase-in, depending on the filing status of the registrant, which, for the Company, were effective for the period ending June 30, 2019. All other provisions were effective on May 2, 2019. Accounting Standards Pending Adoption Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments . In June 2016, the FASB issued guidance which introduces a new forward-looking approach, based on expected losses, to estimate credit losses on certain types of financial instruments, including trade receivables , which will require entities to incorporate considerations of historical information, current information and reasonable and supportable forecasts. The standard will be effective for public business entities that are SEC filers for annual periods beginning after December 15, 2019 and interim periods within those years. Early adoption is permitted. Income Taxes – Simplifying the Accounting for Income Taxes . In December 2019, the FASB issued guidance that simplifies the accounting for income taxes as part of its overall initiative to reduce complexity in applying accounting standards while maintaining or improving the usefulness of the information provided to users of financial statements. The amendments include removal of certain exceptions to the general principles of income taxes, and simplification in several other areas such as accounting for a franchise tax that is partially based on income. The standard will be effective for public business entities that are SEC filers for annual periods beginning after December 15, 2020, and interim periods within those reporting periods. Early adoption is permitted. The Company has not yet assessed the potential impact of implementing this new guidance on its consolidated financial statements. Reclassification As disclosed within other footnotes of the financial statements, segment information reported in the Company’s prior year have been reclassified to conform with the 2019 presentation.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2019
Summary of Significant Accounting Policies [Abstract]
Summary of Significant Accounting Policies	3. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Reporting Currency The functional currency of the Company, as the parent corporate entity, and its operating subsidiaries in the United States, is the U.S. dollar. The functional currency of the Company’s Canadian operations is the Canadian dollar. The reporting currency of the Company is the U.S. dollar. The Company’s consolidated Canadian dollar financial position is translated to U.S. dollars by applying the foreign currency exchange rate in effect at the consolidated balance sheet date. The Company’s consolidated Canadian dollar results of operations and cash flows are translated to U.S. dollars by applying the average foreign currency exchange rate in effect during the reporting period. The resulting translation adjustments are included in other comprehensive income or loss. Gains and losses from foreign currency transactions are included in earnings for the period. Cash Equivalents The Company considers all highly liquid investments with a maturity of three months or less at purchase to be cash equivalents. As of December 31, 2019 and 2018, 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 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, non-hazardous exploration and production (“E&P”) waste treatment, recovery and disposal services, and intermodal services. The following table disaggregates the Company’s revenues by service line for the periods indicated: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 Commercial $ 1,593,217 ​ $ 1,452,831 $ 1,343,590 Residential ​ ​ 1,380,763 ​ ​ 1,189,148 ​ ​ 1,130,842 Industrial and construction roll off ​ ​ 841,173 ​ ​ 768,687 ​ ​ 707,015 Total collection ​ ​ 3,815,153 ​ ​ 3,410,666 ​ ​ 3,181,447 Landfill ​ ​ 1,132,935 ​ ​ 1,063,243 ​ ​ 988,092 Transfer ​ ​ 771,316 ​ ​ 670,129 ​ ​ 589,883 Recycling ​ ​ 64,245 ​ ​ 92,634 ​ ​ 161,730 E&P ​ ​ 271,887 ​ ​ 256,262 ​ ​ 203,473 Intermodal and other ​ ​ 121,137 ​ ​ 139,896 ​ ​ 146,749 Intercompany ​ ​ (787,994) ​ ​ (709,889) ​ ​ (640,886) Total $ 5,388,679 ​ $ 4,922,941 $ 4,630,488 ​ 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 16 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 recognized as of September 30, 2019 was recognized as revenue during the three months ended December 31, 2019 when the service was performed. Commercial customers are typically billed on a monthly basis based on the nature of the services provided during the period. Revenue recognized under these agreements is variable in nature based on the number of residential homes or businesses serviced during the period, the frequency of collection and the volume of waste collected. In addition, certain contracts have annual price escalation clauses that are tied to changes in an underlying base index such as a consumer price index which are unknown at contract inception. Solid waste collection revenue from sources other than customer contracts primarily relates to lease revenue associated with compactors. Revenue from these leasing arrangements was not material and represented an insignificant amount of total revenue for each of the reported periods. Landfill and Transfer Station Revenue at landfills is primarily generated by charging tipping fees on a per ton and/or per yard basis to third parties based on the volume disposed and the nature of the waste. In general, fees are variable in nature and revenue is recognized at the time the waste is disposed at the facility. Revenue at transfer stations is primarily generated by charging tipping or disposal fees on a per ton and/or per yard basis. The fees charged to third parties are based primarily on the market, type and volume or weight of the waste accepted, the distance to the disposal facility and the cost of disposal. In general, fees are billed and revenue is recognized at the time the service is performed. Revenue recognized under these agreements is variable in nature based on the volume of waste accepted at the transfer facility. Many of the Company’s landfill and transfer station customers have entered into one Solid Waste Recycling Solid waste recycling revenues 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 recycling operations and markets collected recyclable materials to third parties for processing before resale. 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 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 including closed loop collection systems, the transportation of waste to the disposal facility in certain markets and the sale of recovered products. E&P activity varies across market areas that are tied to the natural resource basins in which the drilling activity occurs and reflects the regulatory environment, pricing and disposal alternatives available in any given market. 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 generated from the Company’s MSW landfills. Revenue Recognition Service obligations of a long-term nature, e.g., solid waste collection service contracts, are satisfied over time, and revenue is recognized based on the value provided to the customer during the period. The amount billed to the customer is based on variable elements such as the number of residential homes or businesses for which collection services are provided, the volume of waste collected, transported and disposed, and the nature of the waste accepted. The Company does not disclose the value of unsatisfied performance obligations for these contracts as its right to consideration corresponds directly to the value provided to the customer for services completed to date and all future variable consideration is allocated to wholly unsatisfied performance obligations. Additionally, certain elements of long-term customer contracts are unknown upon entering into the contract, including the amount that will be billed in accordance with annual price escalation clauses, fuel recovery fee programs and commodity prices. The amount to be billed is often tied to changes in an underlying base index such as a consumer price index or a fuel or commodity index, and revenue is recognized once the index is established for the period. Accounts Receivable Accounts receivable are recorded when billed or accrued and represent claims against third parties that will be settled in cash. The carrying value of the Company’s receivables, net of the allowance for doubtful accounts, represents their estimated net realizable value. The Company estimates its allowance for doubtful accounts based on historical collection trends, type of customer such as municipal or non-municipal, the age of outstanding receivables and existing economic conditions. If events or changes in circumstances indicate that specific receivable balances may be impaired, further consideration is given to the collectability of those balances and the allowance is adjusted accordingly. Past-due receivable balances are written off when the Company’s internal collection efforts have been unsuccessful in collecting the amount due. Contract Acquisition Costs The incremental direct costs of obtaining a contract, which consist of sales incentives, are recognized as Other assets in the Company’s Consolidated Balance Sheet, and are amortized to Selling, general and administrative expense over the estimated life of the relevant customer relationship, which ranges from one Property and Equipment Property and equipment are stated at cost. Improvements or betterments, not considered to be maintenance and repair, which add new functionality or significantly extend the life of an asset are capitalized. Third-party expenditures related to pending development projects, such as legal and engineering expenses, are capitalized. Expenditures for maintenance and repair costs, including planned major maintenance activities, are charged to expense as incurred. The cost of assets retired or otherwise disposed of and the related accumulated depreciation are eliminated from the accounts in the year of disposal. Gains and losses resulting from disposals of property and equipment are recognized in the period in which the property and equipment is disposed. Depreciation is computed using the straight-line method over the estimated useful lives of the assets or the lease term, whichever is shorter. The estimated useful lives are as follows: ​ ​ ​ ​ Buildings 10 Leasehold and land improvements 3 Machinery and equipment 3 Rolling stock 3 Containers 3 ​ Landfill Accounting The Company utilizes the life cycle method of accounting for landfill costs. This method applies the costs to be capitalized associated with acquiring, developing, closing and monitoring the landfills over the associated consumption of landfill capacity. The Company utilizes the units of consumption method to amortize landfill development costs over the estimated remaining capacity of a landfill. Under this method, the Company includes future estimated construction costs using current dollars, as well as costs incurred to date, in the amortization base. When certain criteria are met, the Company includes expansion airspace, which has not been permitted, in the calculation of the total remaining capacity of the landfill. - Landfill development costs Total landfill costs include the development costs associated with expansion airspace. Expansion airspace is addressed below. - Final capping, closure and post-closure obligations The net present value of landfill final capping, closure and post-closure liabilities are calculated by estimating the total obligation in current dollars, inflating the obligation based upon the expected date of the expenditure and discounting the inflated total to its present value using a credit-adjusted risk-free rate. Any changes in expectations that result in an upward revision to the estimated undiscounted cash flows are treated as a new liability and are inflated and discounted at rates reflecting current market conditions. Any changes in expectations that result in a downward revision (or no revision) to the estimated undiscounted cash flows result in a liability that is inflated and discounted at rates reflecting the market conditions at the time the cash flows were originally estimated. This policy results in the Company’s final capping, closure and post-closure liabilities being recorded in “layers.” The Company’s discount rate assumption for purposes of computing 2019 and 2018 “layers” for final capping, closure and post-closure obligations was 4.75% for both years, which reflects the Company’s long-term credit adjusted risk free rate as of the end of both 2018 and 2017. The Company’s inflation rate assumption was 2.5% for the years ended December 31, 2019 and 2018. In accordance with the accounting guidance on asset retirement obligations, the final capping, closure and post-closure liability is recorded on the balance sheet along with an offsetting addition to site costs which is amortized to depletion expense on a units-of-consumption basis as remaining landfill airspace is consumed. The impact of changes determined to be changes in estimates, based on an annual update, is accounted for on a prospective basis. Depletion expense resulting from final capping, closure and post-closure obligations recorded as a component of landfill site costs will generally be less during the early portion of a landfill’s operating life and increase thereafter. Owned landfills and landfills operated under life-of-site agreements have estimated remaining lives, based on remaining permitted capacity, probable expansion capacity and projected annual disposal volumes, that range from approximately 1 to 176 years, with an average remaining life of approximately 29 years. The costs for final capping, closure and post-closure obligations at landfills the Company owns or operates under life-of-site agreements are generally estimated based on interpretations of current requirements and proposed or anticipated regulatory changes. The following is a reconciliation of the Company’s final capping, closure and post-closure liability balance from December 31, 2017 to December 31, 2019: ​ ​ ​ ​ ​ Final capping, closure and post-closure liability at December 31, 2017 $ 237,817 Liabilities incurred ​ 2,640 Accretion expense associated with landfill obligations ​ 12,777 Closure payments ​ (2,731) Assumption of closure liabilities from acquisitions ​ 4,408 Foreign currency translation adjustment ​ ​ (3,129) Final capping, closure and post-closure liability at December 31, 2018 ​ 251,782 Liabilities incurred ​ 19,846 Accretion expense associated with landfill obligations ​ 14,251 Closure payments ​ (5,059) Assumption of closure liabilities from acquisitions ​ ​ 8,707 Foreign currency translation adjustment ​ 1,947 Final capping, closure and post-closure liability at December 31, 2019 ​ $ 291,474 ​ Liabilities incurred of $19,846 and $2,640 for the years ended December 31, 2019 and 2018, respectively, represent non-cash increases to final capping, closure and post-closure liabilities and are recorded on the Condensed Consolidated Balance Sheets along with an offsetting addition to site costs, which is amortized to depletion expense as the remaining landfill airspace is consumed. The final capping, closure and post-closure liability is included in Other long-term liabilities in the Consolidated Balance Sheets. The Company performs its annual review of its cost and capacity estimates in the first quarter of each year. - Disposal capacity 1) whether the land where the expansion is being sought is contiguous to the current disposal site, and the Company either owns the expansion property or has rights to it under an option, purchase, operating or other similar agreement; 2) whether total development costs, final capping costs, and closure/post-closure costs have been determined; 3) whether internal personnel have performed a financial analysis of the proposed expansion site and have determined that it has a positive financial and operational impact; 4) whether internal personnel or external consultants are actively working to obtain the necessary approvals to obtain the landfill expansion permit; and 5) whether the Company considers it probable that the Company will achieve the expansion (for a pursued expansion to be considered probable, there must be no significant known technical, legal, community, business, or political restrictions or similar issues existing that the Company believes are more likely than not to impair the success of the expansion). It is possible that the Company’s estimates or assumptions could ultimately be significantly different from actual results. In some cases, the Company may be unsuccessful in obtaining an expansion permit or the Company may determine that an expansion permit that the Company previously thought was probable has become unlikely. To the extent that such estimates, or the assumptions used to make those estimates, prove to be significantly different than actual results, or the belief that the Company will receive an expansion permit changes adversely in a significant manner, the costs of the landfill, including the costs incurred in the pursuit of the expansion, may be subject to impairment testing, as described below, and lower profitability may be experienced due to higher amortization rates, higher capping, closure and post-closure rates, and higher expenses or asset impairments related to the removal of previously included expansion airspace. The Company periodically evaluates its landfill sites for potential impairment indicators. The Company’s judgments regarding the existence of impairment indicators are based on regulatory factors, market conditions and operational performance of its landfills. Future events could cause the Company to conclude that impairment indicators exist and that its landfill carrying costs are impaired. Cell Processing Reserves The Company records a cell processing reserve related to its E&P segment for certain locations in Louisiana and Texas for the estimated amount of expenses to be incurred upon the treatment and excavation of oilfield waste received. The cell processing reserve is the future cost to properly treat and dispose of existing waste within the cells at the various facilities. The reserve generally covers estimated costs to be incurred over a period of time up to 24 months, with the current portion representing costs estimated to be incurred in the next 12 months. The estimate is calculated based on current estimated volume in the cells, estimated percentage of waste treated, and historical average costs to treat and excavate the waste. The processing reserve represents the estimated costs to process the volumes of oilfield waste on-hand for which revenue has been recognized. At December 31, 2019 and 2018, the current portion of cell processing reserves was $3,518 and $2,835, respectively, which is included in Accrued liabilities in the Consolidated Balance Sheets. At December 31, 2019 and 2018, the long-term portion of cell processing reserves was $1,270 and $1,211, respectively, which is included in Other long-term liabilities in the Consolidated Balance Sheets. 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 on a straight-line basis over the expected term of the related agreements (ranging from 1 Goodwill and Indefinite-Lived Intangible Assets The Company acquired indefinite-lived intangible assets in connection with certain of its acquisitions. The amounts assigned to indefinite-lived intangible assets consist of the value of certain perpetual rights to provide solid waste collection and transportation services in specified territories and to operate E&P waste treatment and disposal facilities. The Company measures and recognizes acquired indefinite-lived intangible assets at their estimated acquisition date fair values. Indefinite-lived intangible assets are not amortized. Goodwill represents the excess of: (a) the aggregate of the fair value of consideration transferred, the fair value of any noncontrolling interest in the acquiree (if any) and the acquisition date fair value of the Company’s previously held equity interest in the acquiree (if any), over (b) the fair value of assets acquired and liabilities assumed. Goodwill and intangible assets, deemed to have indefinite lives, are subject to annual impairment tests as described below. Goodwill and indefinite-lived intangible assets are tested for impairment on at least an annual basis in the fourth quarter of the year. In addition, the Company evaluates its reporting units for impairment if events or circumstances change between annual tests indicating a possible impairment. Examples of such events or circumstances include, but are not limited to, the following: ● ● ● ● ● The Company elected to early adopt the guidance issued by the FASB “Simplifying the Test for Goodwill Impairment” on January 1, 2017. The new guidance removes Step 2 of the goodwill impairment test, which required a hypothetical purchase price allocation. As such, the impairment analysis is only one step. In this step, the Company estimates the fair value of each of its reporting units, which consisted of testing its five geographic solid waste operating segments and its E&P segment at December 31, 2019, 2018 and 2017, using discounted cash flow analyses. The Company compares the fair value of each reporting unit with the carrying value of the net assets assigned to each reporting unit. If the fair value of a reporting unit is greater than the carrying value of the net assets, including goodwill, assigned to the reporting unit, then no impairment results. If the fair value is less than its carrying value, an impairment charge is recorded for the amount by which the carrying value exceeds its fair value, not to exceed the carrying amount of goodwill. In testing indefinite-lived intangible assets for impairment, the Company compares the estimated fair value of each indefinite-lived intangible asset to its carrying value. If the fair value of the indefinite-lived intangible asset is less than its carrying value, an impairment charge would be recorded to earnings in the Company’s Consolidated Statements of Net Income. During the Company’s annual impairment analysis of its solid waste operations, the Company determined the fair value of each of its five geographic solid waste operating segments at December 31, 2019, 2018 and 2017 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 and growth rates. The cash flows employed in the Company’s 2019 discounted cash flow analyses were based on ten-year financial forecasts, which in turn were based on the 2020 annual budget developed internally by management. These forecasts reflect operating profit margins that were consistent with 2019 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 5.7%. In assessing the reasonableness of the Company’s determined fair values of its reporting units, the Company evaluates its results against its current market capitalization. The Company did not record an impairment charge to any of its five geographic solid waste operating segments as a result of its annual goodwill Upon adopting the goodwill impairment accounting guidance in the first quarter of 2017, the Company performed an updated impairment test for its E&P segment. The impairment test involved measuring the recoverability of goodwill by comparing the E&P segment’s carrying amount, including goodwill, to the fair value of the reporting unit. The fair value was estimated using an income approach employing a discounted cash flow (“DCF”) model. The DCF model incorporated projected cash flows over a forecast period based on the remaining estimated lives of the operating locations comprising the E&P segment. This was based on a number of key assumptions, including, but not limited to, a discount rate of 11.7%, annual revenue projections based on E&P waste resulting from projected levels of oil and natural gas exploration and production activity during the forecast period, gross margins based on estimated operating expense requirements during the forecast period and estimated capital expenditures over the forecast period, all of which were classified as Level 3 in the fair value hierarchy. The impairment test showed the carrying value of the E&P segment exceeded its fair value by an amount in excess of the carrying amount of goodwill, or $77,343. Therefore, the Company recorded an impairment charge of $77,343, consisting of the carrying amount of goodwill at its E&P segment at January 1, 2017, to Impairments and other operating charges in the Consolidated Statements of Net Income during the year ended December 31, 2017. Additionally, the Company evaluated the recoverability of the E&P segment’s indefinite-lived intangible assets (other than goodwill) by comparing the estimated fair value of each indefinite-lived intangible asset to its carrying value. The Company estimated the fair value of the indefinite-lived intangible assets using an excess earnings approach. Based on the result of the recoverability test during the years ended December 31, 2019, 2018 and 2017, the Company did not record an impairment charge. Impairments of Property and Equipment and Finite-Lived Intangible Assets Property, equipment and finite-lived intangible assets are carried on the Company’s consolidated financial statements based on their cost less accumulated depreciation or amortization. Finite-lived intangible assets consist of long-term franchise agreements, contracts, customer lists, permits and other agreements. The recoverability of these assets is tested whenever events or changes in circumstances indicate that their carrying amount may not be recoverable. Typical indicators that an asset may be impaired include, but are not limited to, the following: ● ● ● ● ● If any of these or other indicators occur, a test of recoverability is performed by comparing the carrying value of the asset or asset group to its undiscounted expected future cash flows. If the carrying value is in excess of the undiscounted expected future cash flows, impairment is measured by comparing the fair value of the asset to its carrying value. Fair value is determined by an internally developed discounted projected cash flow analysis of the asset. Cash flow projections are sometimes based on a group of assets, rather than a single asset. If cash flows cannot be separately and independently identified for a single asset, the Company will determine whether an impairment has occurred for the group of assets for which the projected cash flows can be identified. If the fair value of an asset is determined to be less than the carrying amount of the asset or asset group, an impairment in the amount of the difference is recorded in the period that the impairment indicator occurs. Several impairment indicators are beyond the Company’s control, and whether or not they will occur cannot be predicted with any certainty. Estimating future cash flows requires significant judgment and projections may vary from cash flows eventually realized. There are other considerations for impairments of landfills, as described below. During the year ended December 31, 2019, the Company recorded an $8,000 impairment charge, which is included in Impairments and other operating items in the Consolidated Statements of Net Income, for property and equipment associated with a landfill development project in its E&P segment that the Company is no longer pursuing. During the year ended December 31, 2018, the Company did not record an impairment charge for property and equipment. During the year ended December 31, 2017, the Company recorded an $11,038 impairment charge, which is included in Impairments and other operating items in the Consolidated Statements of Net Income, for property and equipment associated with a project to develop a new landfill in its Central segment that the Company is no longer pursuing. There are certain indicators listed above that require significant judgment and understanding of the waste industry when applied to landfill development or expansion projects. A regulator or court may deny or overturn a landfill development or landfill expansion permit application before the development or expansion permit is ultimately granted. Management may periodically divert waste from one landfill to another to conserve remaining permitted landfill airspace. Therefore, certain events could occur in the ordinary course of business and not necessarily be considered indicators of impairment due to the unique nature of the waste industry. Restricted Cash and Restricted Investments Restricted cash and restricted investments consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019 ​ December 31, 2018 ​ ​ Restricted ​ Restricted ​ Restricted ​ Restricted ​ Cash Investments Cash Investments Settlement of insurance claims ​ $ 77,680 ​ $ — ​ $ 66,573 ​ $ — Landfill closure and post-closure obligations ​ ​ 12,324 ​ ​ 48,590 ​ ​ 12,325 ​ ​ 44,939 Other financial assurance requirements ​ ​ 6,479 ​ ​ 2,589 ​ ​ 5,763 ​ ​ 2,547 ​ ​ $ 96,483 ​ $ 51,179 ​ $ 84,661 ​ $ 47,486 ​ See Note 11 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, interest rate swaps and fuel hedges. As of December 31, 2019 and 2018, the carrying values of cash and equivalents, trade receivables, restricted cash and investments, trade payables and contingent considerati

Use of Estimates and Assumption

Use of Estimates and Assumptions	12 Months Ended
	Dec. 31, 2019
Use of Estimates and Assumptions [Abstract]
Use of Estimates and Assumptions	4. USE OF ESTIMATES AND ASSUMPTIONS In preparing the Company’s consolidated financial statements, several estimates and assumptions are made that affect the accounting for and recognition of assets, liabilities, revenues and expenses. These estimates and assumptions must be made because certain of the information that is used in the preparation of the Company’s consolidated financial statements is dependent on future events, cannot be calculated with a high degree of precision from data available or is simply not capable of being readily calculated based on generally accepted methodologies. In some cases, these estimates are particularly difficult to determine and the Company must exercise significant judgment. The most difficult, subjective and complex estimates and the assumptions that deal with the greatest amount of uncertainty are related to the Company’s accounting for landfills, self-insurance accruals, income taxes, allocation of acquisition purchase price, contingent consideration accruals and asset impairments, which are discussed in Note 3. An additional area that involves estimation is when the Company estimates the amount of potential exposure it may have with respect to litigation, claims and assessments in accordance with the accounting guidance on contingencies. Actual results for all estimates could differ materially from the estimates and assumptions that the Company uses in the preparation of its consolidated financial statements.

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2019
Acquisitions [Abstract]
Acquisitions	5. 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 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. 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 costs as expense. The Company acquired 21 individually immaterial non-hazardous solid waste collection, transfer, recycling and disposal businesses during the year ended December 31, 2019. The purchase consideration recorded during this period included contingent consideration based upon future asset and revenue growth associated with the acquired businesses. The fair value of the total contingent consideration recorded during the year ended December 31, 2019 of $14,038 was determined using probability assessments of the expected future cash flows over a one consideration subsequent to the acquisition date will be charged or credited to expense until the contingency is settled. The total acquisition-related costs incurred during the year ended December 31, 2019 for these acquisitions was $12,335. These expenses are included in Selling, general and administrative expenses in the Company’s Consolidated Statements of Net Income. The Company acquired 20 individually immaterial non-hazardous solid waste collection, transfer, recycling and disposal businesses during the year ended December 31, 2018. The purchase price for one of these acquisitions included contingent consideration of $11,593, representing the fair value of up to $12,582 of amounts payable to the former owners based on the achievement of certain operating targets specified in the asset purchase agreement. The fair value of the contingent consideration was determined using probability assessments of the expected future cash flows over the three-year period in which the obligation is expected to be settled, and applying a discount rate of 2.7%. As of December 31, 2019, the obligation recognized at the purchase date has not materially changed. Any changes in the fair value of the contingent consideration subsequent to the acquisition date will be charged or credited to expense until the contingency is settled. The total acquisition-related costs incurred during the year ended December 31, 2018 for these acquisitions was $8,607. These expenses are included in Selling, general and administrative expenses in the Company’s Consolidated Statements of Net Income. The Company acquired 14 individually immaterial non-hazardous solid waste collection, transfer and recycling businesses during the year ended December 31, 2017. The total acquisition-related costs incurred during the year ended December 31, 2017 for these acquisitions was $5,700. 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, 2019, 2018 and 2017: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2019 2018 2017 ​ ​ Acquisitions ​ Acquisitions ​ Acquisitions Fair value of consideration transferred: ​ ​ ​ Cash ​ $ 736,610 ​ $ 830,091 ​ $ 410,695 Debt assumed ​ 95,809 ​ 210,461 ​ 56,958 Notes issued to sellers ​ — ​ — ​ 13,460 Fair value of operations exchanged ​ — ​ — ​ 81,097 Change in open working capital settlements at year end ​ ​ 5,272 ​ ​ (8,507) ​ ​ — ​ ​ 837,691 ​ 1,032,045 ​ 562,210 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired: ​ ​ ​ Accounts receivable ​ 25,220 ​ 23,682 ​ 19,228 Prepaid expenses and other current assets ​ 4,970 ​ 4,614 ​ 10,722 Property and equipment ​ 294,037 ​ 437,914 ​ 169,433 Long-term franchise agreements and contracts ​ 78,312 ​ 10,888 ​ 54,674 Indefinite-lived intangibles ​ — ​ — ​ 5,830 Customer lists ​ 52,422 ​ 133,387 ​ 33,529 Permits and other intangibles ​ ​ 48,141 ​ ​ 23,935 ​ ​ 27,261 Other assets ​ 7 ​ 19 ​ 3,052 Accounts payable and accrued liabilities ​ (19,209) ​ (25,005) ​ (12,020) Deferred revenue ​ (17,245) ​ (16,238) ​ (6,883) Contingent consideration ​ (14,038) ​ (11,669) ​ (2,885) Other long-term liabilities ​ (8,707) ​ (15,532) ​ (1,080) Deferred income taxes ​ (13,287) ​ (391) ​ (50,283) Total identifiable net assets ​ 430,623 ​ 565,604 ​ 250,578 Goodwill ​ $ 407,068 ​ $ 466,441 ​ $ 311,632 ​ Goodwill acquired in 2019 totaling $266,310 is expected to be deductible for tax purposes. Goodwill acquired in 2018 totaling $455,283 is expected to be deductible for tax purposes. Goodwill acquired in 2017 totaling $62,887 is expected to be deductible for tax purposes. The fair value of acquired working capital related to nine individually immaterial acquisitions completed during the year ended December 31, 2019, 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 nine acquisitions are not expected to be material to the Company’s financial position. The gross amount of trade receivables due under contracts acquired during the year ended December 31, 2019, was $27,297, of which $2,077 was expected to be uncollectible. The gross amount of trade receivables due under contracts acquired during the year ended December 31, 2018, was $27,795, of which $4,113 was expected to be uncollectible. The gross amount of trade receivables due under contracts acquired during the year ended December 31, 2017, was $20,746, of which $1,518 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, 2019
Intangible Assets, Net [Abstract]
Intangible Assets, Net	6. INTANGIBLE ASSETS, NET Intangible assets, exclusive of goodwill, consisted of the following at December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ ​ Accumulated Net ​ ​ Carrying ​ Accumulated ​ Impairment ​ Carrying ​ ​ Amount ​ Amortization ​ Loss ​ Amount Finite-lived intangible assets: ​ ​ ​ ​ Long-term franchise agreements and contracts ​ $ 550,340 ​ $ (192,462) ​ $ — ​ $ 357,878 Customer lists ​ 587,562 ​ (308,427) ​ — ​ 279,135 Permits and other ​ 367,127 ​ (63,299) ​ — ​ 303,828 ​ ​ 1,505,029 ​ (564,188) ​ — ​ 940,841 Indefinite-lived intangible assets: ​ ​ ​ ​ Solid waste collection and transportation permits ​ 158,591 ​ — ​ — ​ 158,591 Material recycling facility permits ​ 42,283 ​ — ​ — ​ 42,283 E&P facility permits ​ 59,855 ​ — ​ (38,507) ​ 21,348 ​ ​ 260,729 ​ — ​ (38,507) ​ 222,222 Intangible assets, exclusive of goodwill ​ $ 1,765,758 ​ $ (564,188) ​ $ (38,507) ​ $ 1,163,063 ​ The weighted-average amortization period of long-term franchise agreements and contracts acquired during the year ended December 31, 2019 was 16.1 years. The weighted-average amortization period of customer lists acquired during the year ended December 31, 2019 was 10.5 years. The weighted-average amortization period of finite-lived permits and other acquired during the year ended December 31, 2019 was 38.8 years. ​ Intangible assets, exclusive of goodwill, consisted of the following at December 31, 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ ​ Accumulated Net ​ ​ Carrying ​ Accumulated ​ Impairment ​ Carrying ​ ​ Amount ​ Amortization ​ Loss ​ Amount Finite-lived intangible assets: ​ ​ ​ ​ Long-term franchise agreements and contracts ​ $ 476,833 ​ $ (157,986) ​ $ — ​ $ 318,847 Customer lists ​ 530,614 ​ (232,461) ​ — ​ 298,153 Permits and other ​ 338,601 ​ (49,195) ​ — ​ 289,406 ​ ​ 1,346,048 ​ (439,642) ​ — ​ 906,406 Indefinite-lived intangible assets: ​ ​ ​ ​ ​ ​ Solid waste collection and transportation permits ​ 158,591 ​ — ​ — ​ 158,591 Material recycling facility permits ​ 42,283 ​ — ​ — ​ 42,283 E&P facility permits ​ 59,855 ​ — ​ (38,507) ​ 21,348 ​ ​ 260,729 ​ — ​ (38,507) ​ 222,222 Intangible assets, exclusive of goodwill ​ $ 1,606,777 ​ $ (439,642) ​ $ (38,507) ​ $ 1,128,628 ​ Estimated future amortization expense for the next five years relating to finite-lived intangible assets is as follows: ​ ​ ​ ​ ​ For the year ending December 31, 2020 $ 126,000 For the year ending December 31, 2021 ​ $ 109,234 For the year ending December 31, 2022 ​ $ 94,173 For the year ending December 31, 2023 ​ $ 79,710 For the year ending December 31, 2024 ​ $ 68,350 ​

Property and Equipment, Net

Property and Equipment, Net	12 Months Ended
	Dec. 31, 2019
Property and Equipment, Net [Abstract]
Property and Equipment, Net	7. PROPERTY AND EQUIPMENT, NET Property and equipment, net consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2019 2018 Landfill site costs ​ $ 4,334,562 ​ $ 3,981,870 Rolling stock ​ 2,011,283 ​ 1,736,673 Land, buildings and improvements ​ 1,079,420 ​ 963,903 Containers ​ 764,607 ​ 682,990 Machinery and equipment ​ 749,557 ​ 660,961 Construction in progress ​ 23,739 ​ 25,692 ​ ​ 8,963,168 ​ 8,052,089 Less accumulated depreciation and depletion ​ (3,446,821) ​ (2,883,093) ​ ​ $ 5,516,347 ​ $ 5,168,996 ​ The Company’s landfill depletion expense, recorded in Depreciation in the Consolidated Statements of Net Income, for the years ended December 31, 2019, 2018 and 2017, was $225,687, $206,404 and $196,314, respectively. ​

Leases

Leases	12 Months Ended
	Dec. 31, 2019
Lessee Disclosure [Abstract]
Leases	8. LEASES The Company rents certain equipment and facilities under both short-term agreements and non-cancelable operating lease agreements. 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 leases are periodically reviewed for impairment losses. The Company uses the long-lived assets 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 year ended December 31, 2019. The Company monitors for events or changes in circumstances that require a reassessment of one of its leases. When a reassessment results in the remeasurement of a lease liability, a corresponding adjustment is made to the carrying amount of the corresponding ROU asset. The Company did not recognize any significant remeasurements during the year ended December 31, 2019. The Company has elected not to recognize ROU assets and lease liabilities for short-term leases that have a lease term of 12 months or less. The Company has elected to apply the short-term lease recognition and measurement exemption allowed for in the lease accounting standard. The Company recognizes the lease payments associated with its short-term leases as an expense on a straight-line basis over the lease term. Lease cost for operating leases for the year ended December 31, 2019 was as follows: ​ ​ ​ ​ ​ ​ ​ Year Ended ​ December 31, 2019 Operating lease cost ​ $ 38,710 ​ Supplemental cash flow information and non-cash activity related to the Company’s operating leases are as follows: ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, 2019 Operating cash flow information: ​ ​ ​ Cash paid for amounts included in the measurement of lease liabilities ​ $ 38,226 Non-cash activity: ​ ​ ​ Right-of-use assets obtained in exchange for lease liabilities ​ $ 10,746 ​ Weighted-average remaining lease term and discount rate for the Company’s operating leases are as follows: ​ ​ ​ ​ ​ ​ ​ Year Ended ​ December 31, 2019 Weighted average remaining lease term ​ 8.7 years Weighted average discount rate ​ 3.99 % ​ As of December 31, 2019, future minimum lease payments, as calculated under the new lease guidance and reconciled to the operating lease liability, are as follows: ​ ​ ​ ​ ​ 2020 $ 36,718 2021 ​ 33,432 2022 ​ 32,087 2023 ​ 28,750 2024 ​ 20,382 Thereafter ​ 75,716 Minimum lease payments ​ 227,085 Less: imputed interest ​ (37,123) Present value of minimum lease payments ​ ​ 189,962 Less: current portion of operating lease liabilities ​ ​ (29,929) Long-term portion of operating lease liabilities ​ $ 160,033 ​ As of December 31, 2018, minimum lease payments under non-cancelable operating leases by period were expected to be as follows: ​ ​ ​ ​ ​ 2019 $ 37,902 2020 ​ ​ 35,204 2021 ​ ​ 32,259 2022 ​ ​ 30,974 2023 ​ ​ 27,882 Thereafter ​ ​ 94,205 ​ ​ $ 258,426 ​ A summary of rent expense for both short-term agreements and non-cancelable operating lease agreements for the years ended December 31, 2018 and 2017 was as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ 2018 2017 Rent expense ​ $ 42,646 ​ $ 43,383 ​

Accrued Liabilities

Accrued Liabilities	12 Months Ended
	Dec. 31, 2019
Accrued Liabilities [Abstract]
Accrued Liabilities	9. ACCRUED LIABILITIES Accrued liabilities consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2019 2018 Insurance claims ​ $ 127,029 ​ $ 119,506 Payroll and payroll-related ​ 71,593 ​ 87,136 Interest payable ​ 17,286 ​ 16,971 Final capping, closure and post-closure liability - current portion ​ ​ 7,707 ​ ​ 26,126 Unrealized cash flow hedge losses ​ 3,680 ​ — Cell processing reserve - current portion ​ 3,518 ​ 2,835 Environmental remediation reserve - current portion ​ 2,314 ​ 3,592 Share-based compensation plan liability – current portion ​ 930 ​ 6,209 Other ​ 47,251 ​ 53,295 ​ ​ $ 281,308 ​ $ 315,670 ​

Long-Term Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2019
Long-Term Debt [Abstract]
Long-Term Debt	10. LONG-TERM DEBT The following table presents the Company’s long-term debt as of December 31, 2019 and 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ ​ 2019 2018 Revolver under Credit Agreement, bearing interest ranging from 2.90% to 3.18% (a) ​ $ 916,247 ​ $ 481,610 ​ Term loan under Credit Agreement, bearing interest at 2.90% (a) ​ 700,000 ​ 1,237,500 ​ 5.25% Senior Notes due 2019 ​ — ​ 175,000 ​ 4.64% Senior Notes due 2021 ​ 100,000 ​ 100,000 ​ 2.39% Senior Notes due 2021 ​ 150,000 ​ 150,000 ​ 3.09% Senior Notes due 2022 ​ 125,000 ​ 125,000 ​ 2.75% Senior Notes due 2023 ​ 200,000 ​ 200,000 ​ 3.24% Senior Notes due 2024 ​ 150,000 ​ 150,000 ​ 3.41% Senior Notes due 2025 ​ 375,000 ​ 375,000 ​ 3.03% Senior Notes due 2026 ​ 400,000 ​ 400,000 ​ 3.49% Senior Notes due 2027 ​ 250,000 ​ 250,000 ​ 4.25% Senior Notes due 2028 ​ ​ 500,000 ​ ​ 500,000 ​ 3.50% Senior Notes due 2029 ​ ​ 500,000 ​ ​ — ​ Tax-exempt bonds ​ — ​ 15,930 ​ Notes payable to sellers and other third parties, bearing interest ranging from 2.75% to 10.90%, principal and interest payments due periodically with due dates ranging from 2020 to 2036 (a) ​ 9,638 ​ 14,653 ​ ​ ​ 4,375,885 ​ 4,174,693 ​ Less – current portion ​ (465) ​ (1,786) ​ Less – debt issuance costs ​ (21,638) ​ (19,442) ​ ​ ​ $ 4,353,782 ​ $ 4,153,465 ​ (a) Interest rates represent the interest rates incurred at December 31, 2019. Credit Agreement The Company has a revolving credit and term loan agreement (the “Credit Agreement”) with Bank of America, N.A., acting through its Canada Branch, as global agent, the swing line lender and letter of credit issuer, Bank of America, N.A., as the U.S. Agent and a letter of credit issuer, the lenders (the “Lenders”) and any other financial institutions from time to time party thereto. There are no subsidiary guarantors under the Credit Agreement. The Credit Agreement has a scheduled maturity date of March 21, 2023. Details of the Credit Agreement are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ ​ 2019 2018 Revolver under Credit Agreement ​ ​ ​ Available ​ $ 538,642 ​ $ 955,779 ​ ​ Letters of credit outstanding ​ $ 107,611 ​ $ 125,111 ​ ​ Total amount drawn, as follows: ​ $ 916,247 ​ $ 481,610 ​ ​ Amount drawn - U.S. LIBOR rate loan ​ $ 897,000 ​ $ 357,000 ​ ​ Interest rate applicable - U.S. LIBOR rate loan ​ ​ 2.90 % ​ 3.62 % ​ Interest rate margin - U.S. LIBOR rate loan ​ ​ 1.10 % ​ 1.10 % ​ Amount drawn – Canadian bankers’ acceptance ​ $ 19,247 ​ $ 124,610 ​ ​ Interest rate applicable – Canadian bankers’ acceptance ​ 3.18 % 3.40 % ​ Interest rate acceptance fee – Canadian bankers’ acceptance ​ 1.10 % 1.10 % ​ Commitment – rate applicable ​ 0.12 % 0.12 % ​ Term loan under Credit Agreement ​ ​ ​ ​ ​ Amount drawn – U.S. based LIBOR loan ​ $ 700,000 ​ $ 1,237,500 ​ ​ Interest rate applicable – U.S. based LIBOR loan ​ 2.90 % 3.62 % ​ Interest rate margin – U.S. based LIBOR loan ​ 1.10 % ​ 1.10 % ​ ​ Pursuant to the terms and conditions of the Credit Agreement, the Lenders provide a $3,200,000 credit facility to the Company, consisting of (i) revolving advances up to an aggregate principal amount of $1,562,500 at any one time outstanding, and (ii) a term loan in an aggregate principal amount of $1,637,500. As part of the aggregate commitments under the revolving advances, the Credit Agreement provides for letters of credit to be issued at the request of the Company in an aggregate amount not to exceed $320,000 and for swing line loans to be issued at the request of the Company in an aggregate amount not to exceed the lessor of $75,000 and the aggregate commitments under the revolving advances. Both the letter of credit sublimit and the swing line sublimit are part of, and not in addition to, the aggregate commitments under the revolving advances. Subject to certain specified conditions and additional deliveries, the Company has the option to request increases in the aggregate commitments for revolving advances and one or more additional term loans, provided that (i) the aggregate principal amount of such requests does not exceed $500,000 and (ii) the aggregate principal amount of commitments and term loans under the credit facility does not exceed $3,700,000. The Company has $3,939 of debt issuance costs related to the Credit Agreement recorded in Other assets, net in the Consolidated Balance Sheets at December 31, 2019, which are being amortized through the maturity date, or March 21, 2023. Advances are available under the Credit Agreement in U.S. dollars and Canadian dollars. Interest accrues on the term loan at a LIBOR rate or a base rate, at the Company’s option, plus an applicable margin. Interest accrues on revolving advances, at the Company’s option, (i) at a LIBOR rate or a base rate for U.S. dollar borrowings, plus an applicable margin, and (ii) at the Canadian prime rate for Canadian dollar borrowings, plus an applicable margin. Canadian dollar borrowings are also available by way of bankers’ acceptances or BA equivalent loans (“BA loans”), subject to the payment of a drawing fee. The fees for letters of credit in US dollars and Canadian dollars are also based on the applicable margin. The applicable margin used in connection with interest rates and fees is based on the Company’s Leverage Ratio (as defined below). The applicable margin for LIBOR rate loans, drawing fees for bankers’ acceptance and BA loans and letter of credit fees ranges from 1.00% to 1.50%, and the applicable margin for base rate loans, Canadian prime rate loans and swing line loans ranges from 0.00% to 0.50%. The Company will also pay a fee based on its Leverage Ratio (as defined below) on the actual daily unused amount of the aggregate revolving commitments. The borrowings under the Credit Agreement are unsecured. The Credit Agreement contains customary representations, warranties, covenants and events of default, including, among others, a change of control event of default and limitations on the incurrence of indebtedness and liens, new lines of business, mergers, transactions with affiliates and burdensome agreements. During the continuance of an event of default, the Lenders may take a number of actions, including, among others, declaring the entire amount then outstanding under the Credit Agreement to be due and payable. The Credit Agreement includes a financial covenant limiting, as of the last day of each fiscal quarter, the ratio of (a) (i) Consolidated Total Funded Debt (as defined in the Credit Agreement) as of such date less (ii) the sum of cash and cash equivalents of the Company and its subsidiaries on a dollar-for-dollar basis as of such date in excess of $50,000 up to a maximum of $200,000 (such that the maximum amount of reduction pursuant to this calculation does not exceed $150,000) to (b) Consolidated EBITDA (as defined in the Credit Agreement), measured for the preceding 12 months (the “Leverage Ratio”), to not more than 3.50 to 1.00 (or 3.75 to 1.00 during material acquisition periods, subject to certain limitations). The Credit Agreement also includes a financial covenant requiring the ratio of Consolidated EBIT (as defined in the Credit Agreement) to Consolidated Total Interest Expense (as defined in the Credit Agreement), in each case, measured for the preceding 12 months, (the “Interest Coverage Ratio”) to be not less than 2.75 to 1.00. As of December 31, 2019 and 2018, the Company was in compliance with all applicable covenants in the Credit Agreement. 2016 Master Note Purchase Agreement On June 1, 2016, the Company entered into a Master Note Purchase Agreement (as supplemented by the First Supplement dated as of February 13, 2017 (the “2016 First Supplement”) and as amended, restated, amended and restated, assumed, supplemented or modified from time to time, the “2016 NPA”) with certain accredited institutional investors. On April 20, 2017, pursuant to the 2016 NPA, and the 2016 First Supplement, the Company issued and sold to certain accredited institutional investors $400,000 aggregate principal amount of senior unsecured notes consisting of $150,000 aggregate principal amount, which will mature on April 20, 2024, with an annual interest rate of 3.24% (the “2024 Senior Notes”) and $250,000 aggregate principal amount, which will mature on April 20, 2027, with an annual interest rate of 3.49% (the “2027 Senior Notes” and collectively with the 2024 Senior Notes, the “2017A Senior Notes”) in a private placement. On March 21, 2018, the Company entered into that certain Amendment No. 1 to Master Note Purchase Agreement (the “2016 NPA First Amendment”), with each of the holders party thereto, which amended the 2016 NPA. The 2016 NPA First Amendment, among other things, provided for certain amendments to the 2016 NPA to facilitate (i) certain conforming changes to align certain provisions of the 2016 NPA, the 2008 NPA (as defined below) and the Credit Agreement and (ii) the release of all subsidiary guarantors in relation to obligations under the 2016 NPA and the 2016 NPA Notes (as defined below) (the “2016 Release”). Pursuant to the terms and conditions of the 2016 NPA, the Company has outstanding senior unsecured notes (the “2016 NPA Notes”) at December 31, 2019 consisting of (i) $150,000 of 2.39% senior notes due June 1, 2021 (the “New 2021 Senior Notes”), (ii) $200,000 of 2.75% senior notes due June 1, 2023 (the “2023 Senior Notes”), (iii) $400,000 of 3.03% senior notes due June 1, 2026 (the “2026 Senior Notes”) and (iv) $400,000 of the 2017A Senior Notes. The New 2021 Senior Notes, the 2023 Senior Notes, the 2026 Senior Notes and the 2017A Senior Notes bear interest at fixed rates with interest payable in arrears semi-annually, and on the respective maturity dates, until the principal thereunder becomes due and payable. The Company is amortizing the $9,011 of debt issuance costs through the maturity dates of the respective notes. Under the terms and conditions of the 2016 NPA, the Company is authorized to issue and sell notes in the aggregate principal amount of $1,500,000, inclusive of the outstanding $1,150,000 aggregate principal amount of 2016 NPA Notes that have been issued and sold by the Company, provided that the purchasers of the 2016 NPA Notes shall not have any obligation to purchase any additional notes issued pursuant to the 2016 NPA. The 2016 NPA Notes are unsecured obligations and rank pari passu The 2016 NPA Notes are subject to representations, warranties, covenants and events of default customary for a private placement of senior unsecured notes. Upon the occurrence of an event of default, payment of the 2016 NPA Notes may be accelerated by the holders of the 2016 NPA Notes. The 2016 NPA Notes may also be prepaid by the Company at par plus a make-whole amount determined by the amount of the excess, if any, of the discounted value of the remaining scheduled payments with respect to the called principal of such 2016 NPA Notes minus the amount of such called principal, provided that the make whole shall in no event be less than zero. The discounted value is determined using market-based discount rates. In addition, the Company will be required to offer to prepay the 2016 NPA Notes upon certain changes in control. The 2016 NPA also contemplates certain offers of prepayments for specified tax reasons or certain noteholder sanctions events. The 2016 NPA requires that the Company comply with the specified quarterly leverage ratio and interest coverage ratio, in each case, as of the last day of each fiscal quarter. The required leverage ratio cannot exceed 3.75 to 1.00. The required interest coverage ratio must not be less than 2.75 to 1.00. As of December 31, 2019 and 2018, the Company was in compliance with all applicable covenants in the 2016 NPA. 2008 Master Note Purchase Agreement In July 2008, the Company, certain subsidiaries of the Company (together with the Company, the “Obligors”) and certain accredited institutional investors entered into that certain Master Note Purchase Agreement, dated July 15, 2008 (as amended, restated, assumed, supplemented or otherwise modified from time to time, the “2008 NPA”). On March 21, 2018, the Company entered into that certain Amendment No. 7 to the 2008 NPA (the “2008 NPA Seventh Amendment”), with each of the holders party thereto, which amended the 2008 NPA. The 2008 NPA Seventh Amendment, among other things, provided certain amendments to the 2008 NPA to facilitate (i) certain conforming changes to align the provisions of the 2008 NPA, the 2016 NPA and the Credit Agreement and (ii) the release of all subsidiary guarantors in relation to obligations under the 2008 NPA and the 2008 NPA Notes (the “2008 Release”). Pursuant to the terms and conditions of the 2008 NPA, the Company has outstanding senior unsecured notes (the “2008 NPA Notes”) at December 31, 2019 consisting of (i) $100,000 of 4.64% senior notes due 2021 (the “2021 Senior Notes”), (ii) $125,000 of 3.09% senior notes due 2022 (the “2022 Senior Notes”) and (iii) $375,000 of 3.41% senior notes due 2025 (the “2025 Senior Notes”). The 2021 Senior Notes, the 2022 Senior Notes and the 2025 Senior Notes bear interest at fixed rates with interest payable in arrears semi-annually, and on the respective maturity dates, until the principal thereunder becomes due and payable. The Company is amortizing the $3,863 of debt issuance costs through the maturity dates of the respective notes. The Company repaid at maturity its $50,000 of 4.00% senior notes due April 2018 (the “2018 Senior Notes”) in April 2018. The Company also repaid at maturity its $175,000 of 5.25% senior notes due 2019 (the “2019 Senior Notes”) in November 2019. Under the terms and conditions of the 2008 NPA, the Company is authorized to issue and sell notes in the aggregate principal amount of $1,250,000, provided that the purchasers of the 2008 NPA Notes shall not have any obligation to purchase any additional notes issued pursuant to the 2008 NPA. The 2008 NPA Notes are unsecured obligations and rank pari passu The 2008 NPA Notes are subject to representations, warranties, covenants and events of default customary for a private placement of senior unsecured notes. Upon the occurrence of an event of default, payment of the 2008 NPA Notes may be accelerated by the holders of the 2008 NPA Notes. The 2008 NPA Notes may also be prepaid by the Company at par plus a make-whole amount determined by the amount of excess, if any, of the discounted value of the remaining scheduled payments with respect to the called principal of such 2008 NPA Notes minus the amount of such called principal, provided that the make whole shall in no event be less than zero. The discounted value is determined using market-based discount rates. In addition, the Company will be required to offer to prepay the 2008 NPA Notes upon certain changes in control; however, no such prepayment offer was accepted in connection with the Progressive Waste acquisition. The 2008 NPA also contemplates certain offers of prepayments for specified tax reasons or certain noteholder sanctions events. The 2008 NPA requires that the Company comply with the specified quarterly leverage ratio and interest coverage ratio, in each case, as of the last day of each fiscal quarter. The required leverage ratio cannot exceed 3.75 to 1.00. The required interest coverage ratio must not be less than 2.75 to 1.00. As of December 31, 2019 and 2018, the Company was in compliance with all applicable covenants in the 2008 NPA. Senior Notes due 2028 and 2029 On November 16, 2018, the Company completed an underwritten public offering of $500,000 aggregate principal amount of its 4.25% Senior Notes due 2028 (the “2028 Senior Notes”). The 2028 Senior Notes were issued under the Indenture, dated as of November 16, 2018 (the “Base Indenture”), by and between the Company and U.S. Bank National Association, as trustee (the “Trustee”), as supplemented by the First Supplemental Indenture, dated as of November 16, 2018 (the Base Indenture as so supplemented, the “Indenture”). The Company will pay interest on the 2028 Senior Notes semi-annually in arrears and the 2028 Senior Notes will mature on December 1, 2028. The 2028 Senior Notes are the Company’s senior unsecured obligations, ranking equally in right of payment with its other existing and future unsubordinated debt and senior to any of its future subordinated debt. The 2028 Senior Notes are not guaranteed by any of the Company’s subsidiaries. The Company is amortizing the $5,052 of debt issuance costs through the maturity date. 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 2029 (the “2029 Senior Notes”). The 2029 Senior Notes were issued under the Indenture, dated as of November 16, 2018 (the “Base Indenture”), by and between the Company and U.S. Bank National Association, as trustee (the “Trustee”), as supplemented by the Second Supplemental Indenture, dated as of April 16, 2019 (the Base Indenture as so supplemented, the “Indenture”). The Company will pay interest on the 2029 Senior Notes semi-annually in arrears and the 2029 Senior Notes will mature on May 1, 2029. The 2029 Senior Notes are senior unsecured obligations, ranking equally in right of payment with the Company’s other existing and future unsubordinated debt and senior to any of the Company’s future subordinated debt. The 2029 Senior Notes are not guaranteed by any of the Company’s subsidiaries. The Company is amortizing the $4,644 of debt issuance costs through the maturity date. 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. ​ Under certain circumstances, the Company may become obligated to pay additional amounts (the “Additional Amounts”) with respect to the 2028 and/or 2029 Senior Notes (the “Notes”) to ensure that the net amounts received by each holder of the 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 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 Notes having power to tax, and the Company cannot avoid such payments of Additional Amounts through reasonable measures, then the Company may redeem the 2028 and/or 2029 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 Notes may require the Company to repurchase all or a portion of the Notes for cash at a price equal to 101% of the aggregate principal amount of such Notes, plus any accrued but unpaid interest to, but excluding, the date of repurchase. ​ The covenants in the Indenture include limitations on liens, sale-leaseback transactions and mergers and sales of all or substantially all of the Company’s assets. The Indenture also includes customary events of default with respect to the Notes. As of December 31, 2019, the Company was in compliance with all applicable covenants in the Indenture. ​ Upon an event of default, the principal of and accrued and unpaid interest on all the 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 2028 and/or 2029 Senior Notes. Upon such a declaration, such principal and accrued interest on all of the 2028 and/or 2029 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 2028 and/or 2029 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 Notes. Tax-Exempt Bonds In January 2019, the Company gave notice to redeem its LeMay Washington Bond with a remaining principal balance of $15,930 prior to the April 1, 2033 maturity date. The Company paid in full the principal and accrued interest on this bond on March 6, 2019. The Company has no further tax-exempt bond financings. As of December 31, 2019, aggregate contractual future principal payments by calendar year on long-term debt are due as follows: ​ ​ ​ ​ ​ 2020 $ 465 2021 ​ 254,298 2022 ​ 125,430 2023 ​ 1,816,703 2024 ​ 150,483 Thereafter ​ 2,028,506 ​ ​ $ 4,375,885 ​

Fair Value of Financial Instrum

Fair Value of Financial Instruments	12 Months Ended
	Dec. 31, 2019
Fair Value of Financial Instruments [Abstract]
Fair Value of Financial Instruments	11. 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, 2019 and 2018, 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 and 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 cash and investments measured at fair value are invested primarily in money market accounts, bank time deposits, U.S. government and agency securities and Canadian bankers’ acceptance notes. The Company’s assets and liabilities measured at fair value on a recurring basis at December 31, 2019 and 2018, were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurement at December 31, 2019 Using ​ ​ ​ Quoted Prices in Significant ​ ​ ​ ​ ​ ​ ​ Active Markets ​ Other ​ Significant ​ ​ ​ ​ ​ for Identical ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Assets ​ Inputs ​ Inputs ​ ​ Total ​ (Level 1) ​ (Level 2) ​ (Level 3) Interest rate swap derivative instruments – net liability position ​ $ (39,802) ​ $ — ​ $ (39,802) ​ $ — Restricted cash and investments ​ $ 147,318 ​ $ — ​ $ 147,318 ​ $ — Contingent consideration ​ $ (68,984) ​ $ — ​ $ — ​ $ (68,984) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurement at December 31, 2018 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 ​ $ 12,098 ​ $ — ​ $ 12,098 ​ $ — Restricted cash and investments ​ $ 131,422 ​ $ — ​ $ 131,422 ​ $ — Contingent consideration ​ $ (54,615) ​ $ — ​ $ — ​ $ (54,615) ​ The following table summarizes the changes in the fair value for Level 3 liabilities related to contingent consideration for the years ended December 31, 2019 and 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 Beginning balance ​ $ 54,615 ​ $ 47,285 ​ Contingent consideration recorded at acquisition date ​ 14,038 ​ 11,669 ​ Payment of contingent consideration recorded at acquisition date ​ (3,200) ​ (6,127) ​ Payment of contingent consideration recorded in earnings ​ — ​ (11) ​ Adjustments to contingent consideration ​ ​ 1,498 ​ 349 ​ Interest accretion expense ​ 1,852 ​ 1,756 ​ Foreign currency translation adjustment ​ 181 ​ (306) ​ Ending balance ​ $ 68,984 ​ $ 54,615 ​ ​

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2019
Commitments and Contingencies [Abstract]
Commitments and Contingencies	12. 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, 2019 and 2018, the Company had provided customers and various regulatory authorities with surety bonds in the aggregate amounts of approximately $661,593 and $619,830, respectively, to secure its asset closure and retirement requirements and $419,259 and $357,820, 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 $392,592 and $381,770 were outstanding as of December 31, 2019 and 2018, 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, 2019, the Company’s unconditional purchase obligations consist of multiple fixed-price fuel purchase contracts under which it has 49.0 million gallons remaining to be purchased for a total of $129,373. These fuel purchase contracts expire on or before December 31, 2021. As of December 31, 2019, future minimum purchase commitments, by calendar year, are as follows: ​ ​ ​ ​ ​ 2020 $ 76,799 2021 ​ 52,574 ​ ​ $ 129,373 ​ 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, 2019 and 2018, the current portion of remediation reserves was $2,314 and $3,592, respectively, which is included in Accrued liabilities in the Consolidated Balance Sheets. At December 31, 2019 and 2018, the long-term portion of remediation reserves was $18,770 and $18,362, respectively, which is included in Other long-term liabilities in the Consolidated Balance Sheets. Any substantial increase in the liabilities for remediation of environmental damage incurred by the Company could have a material adverse effect on the Company’s financial condition, results of operations or cash flows. Legal Proceedings In the normal course of its business and as a result of the extensive governmental regulation of the solid waste and E&P waste industries, the Company is subject to various judicial and administrative proceedings involving Canadian regulatory authorities as well as U.S. federal, state and local agencies. In these proceedings, an agency may subpoena the Company for records, or seek to impose fines on the Company or revoke or deny renewal of an authorization held by the Company, including an operating permit. From time to time, the Company may also be subject to actions brought by special interest or other groups, adjacent landowners or residents in connection with the permitting and licensing of landfills, transfer stations, and E&P waste treatment, recovery and disposal operations, or alleging environmental damage or violations of the permits and licenses pursuant to which the Company operates. 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, 2019, there is no current proceeding or litigation involving the Company or its property that the Company believes could have a material adverse effect on its business, financial condition, results of operations or cash flows. Lower Duwamish Waterway Superfund Site Allocation Process In November 2012, the Company’s subsidiary, Northwest Container Services, Inc. (“NWCS”), was named by the U.S. Environmental Protection Agency, Region 10 (the “EPA”) as a potentially responsible party (“PRP”), along with more than 100 others, under the Comprehensive Environmental Response, Compensation and Liability Act (“CERCLA” or the “Superfund” law) with respect to the Lower Duwamish Waterway Superfund Site (the “LDW Site”). Listed on the National Priorities List in 2001, the LDW Site is a five-mile stretch of the Duwamish River flowing into Elliott Bay in Seattle, Washington. A group of PRPs known as the Lower Duwamish Working Group (“LDWG”) and consisting of the City of Seattle, King County, the Port of Seattle, and Boeing Company conducted a Remedial Investigation/Feasibility Study for the LDW Site. On December 2, 2014, the EPA issued its Record of Decision (the “ROD”) describing the selected clean-up remedy, and therein estimated that clean-up costs (in present value dollars as of November 2014) would total approximately $342,000. However, it is possible that additional costs could be incurred based upon various factors. The EPA estimates that it will take seven years to implement the clean-up. The ROD also requires ten years of monitoring following the clean-up, and provides that if clean-up goals have not been met by the end of this period, then additional clean-up activities, at additional cost, may be required at that time. Implementation of the clean-up will not begin until after the ongoing Early Action Area (“EAA”) clean-ups have been completed. Typically, costs for monitoring may be in addition to those expended for the clean-up. While three of the EAA clean-ups have been completed to date, some work remains to be done on three other EAAs. Implementation of the clean-up also must await additional baseline sampling throughout the LDW Site and the preparation of a remedial design for performing the clean-up. On April 27, 2016, the LDWG entered into a third amendment of its Administrative Order on Consent with the EPA (the “AOC 3”) in which it agreed to perform the additional baseline sediment sampling and certain technical studies needed to prepare the actual remedial design. The LDWG and the EPA entered into a fourth amendment to the AOC in July 2018 primarily addressing development of a proposed remedy for the upper reach of the LDW Site, river mile 3 to river mile 5. At the April 24, 2019 stakeholders meeting the LDWG projected completion of the remedial design for the upper reach could be completed by August 2024. On August 16, 2016, the EPA sent individual letters to each of the PRPs for the LDW Site, including NWCS, stating that it expects to initiate negotiations with all PRPs in early 2018 relating to a Remedial Design/Remedial Action (“RD/RA”) Consent Decree. An RD/RA Consent Decree provides for the cleanup of the entire site and is often referred to as a “global settlement.” In August 2014, NWCS entered into an Alternative Dispute Resolution Memorandum of Agreement with several dozen other PRPs and a neutral allocator to conduct a confidential and non-binding allocation of certain past response costs allegedly incurred at the LDW Site as well as the anticipated future response costs associated with the clean-up. The pre-remedial design work under the AOC 3 was not expected to conclude until the end of 2019, and in March 2017, the PRPs provided the EPA with notice that the allocation was not scheduled to conclude until mid-2019. Later extensions pushed the allocation conclusion date to early 2020 and the EPA was informed of that schedule. The allocation participants voted in June 2019 to extend the final allocation report deadline to July 2020. The EPA has been informed of that change. In January 2020, the allocator informed the parties that the allocation report will be delayed but he did not provide an expected delivery date. In June 2017, attorneys for the EPA informed attorneys for several PRPs that the EPA expected to begin RD/RA negotiations in the late summer or early fall of 2018. Those negotiations have not been scheduled and there is no recent indication from the EPA regarding when they will begin. NWCS is defending itself vigorously in this confidential allocation process. At this point, the Company is not able to determine the likelihood of the allocation process being completed as intended by the participating PRPs, its specific allocation, or the likelihood of the parties then negotiating a global settlement with the EPA. Thus, NWCS cannot reasonably determine the likelihood of any outcome in this matter, including its potential liability. On February 11, 2016, NWCS received a letter (the “Letter”) from the United States Department of Commerce, National Oceanic and Atmospheric Administration (“NOAA”), describing certain investigatory activities conducted by the Elliott Bay Trustee Council (the “Council”). The Council consists of all of the natural resources trustees for the LDW Site as well as two nearby Superfund sites, the Harbor Island site and the Lockheed West site. The members of the Council include the United States, on behalf of the U.S. National Oceanic and Atmospheric Administration and the U.S. Department of the Interior, the Washington State Department of Ecology, and the Suquamish and Muckleshoot Indian Tribes (together, the “Trustees”). The Letter appears to allege that NWCS may be a potentially liable party that allegedly contributed to the release of hazardous substances that have injured natural resources at the LDW Site. Damages to natural resources are in addition to clean-up costs. The Letter, versions of which NWCS believes were sent to all or a group of the PRPs for the LDW Site, also notified its recipients of their opportunity to participate in the Trustees’ development of an Assessment Plan and the performance of a Natural Resources Damages Assessment (“NRDA”) in accordance with the Assessment Plan for both the LDW Site and the east and west waterways of the Harbor Island site. NWCS timely responded with correspondence to the NOAA Office of General Counsel, in which it declined the invitation at that time. NWCS does not know how other PRPs responded to the Letter, and has not received any further communication from NOAA or the Trustees. The Trustees have not responded to NWCS’ letter. The Trustees released their Assessment Plan in March 2019. The Assessment Plan does not set forth a timeline for implementation. At this point, the Company is not able to determine the likelihood or amount of an assessment of natural resource damages against NWCS in connection with this matter. Los Angeles County, California Landfill Expansion Litigation A. Chiquita Canyon, LLC Lawsuit Against Los Angeles County In October 2004, the Company’s subsidiary, Chiquita Canyon, LLC (“CCL”), then under prior ownership, filed an application (the “Application”) with the County of Los Angeles (the “County”) Department of Regional Planning (“DRP”) for a conditional use permit (the “CUP”) to authorize the continued operation and expansion of the Chiquita Canyon Landfill (the “Landfill”). The Landfill has operated since 1972, and as a regional landfill, accepted approximately two million tons of materials for disposal and beneficial use in 2018. 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 reduce the historical landfill operations and represent a large increase in aggregate taxes and fees. CCL objected to many of the requirements imposed by the Commission. Current estimates for new costs imposed on CCL under the CUP are in excess of $300,000. CCL appealed the Commission’s decision to the County Board of Supervisors, but the appeal was not successful. At a subsequent hearing, on July 25, 2017, the Board of Supervisors approved the CUP. On October 20, 2017, CCL filed in the Superior Court of California, County of Los Angeles a verified petition for writ of mandate and complaint against the County and the County Board of Supervisors captioned Chiquita Canyon, LLC v. County of Los Angeles, On September 14, 2018, CCL sought discretionary review by the California Court of Appeal of the Superior Court’s July 17, 2018 decision barring the challenge to 13 operational conditions. The Court of Appeal agreed to hear CCL’s appeal and on February 25, 2019, the Court of Appeal issued its decision, reversing the trial court orders that granted the County’s motion to strike and demurrer. The Court of Appeal ruled that CCL had adequately pled a claim that the County was equitably estopped from contending that CCL had forfeited its rights to challenge the legality of the 13 operational conditions. CCL’s Complaint sets forth that CCL relied on representations made by the County in 2017 that CCL could reserve its legal rights to challenge the CUP in a separate reservation of rights letter rather than the affidavit of acceptance of the CUP that the County compelled Chiquita to file. At a trial setting conference on May 28, 2019, the equitable estoppel issues in this case were discussed and the Superior Court continued the June 18, 2019 trial date to April 23, 2020. The Superior Court also set an evidentiary hearing on the equitable estoppel issues for November 12, 2019. Discovery occurred on these issues in July through September 2019. Following full briefing and oral argument on November 12, 2019, the Superior Court issued its decision on November 13th, finding that the County was estopped from contending that CCL has waived its rights to challenge the legality of the 13 operational conditions. The County sought interlocutory review of the Superior Court’s decision in the Court of Appeal, which denied the County’s petition on February 7, 2020. Trial remains set for April 23, 2020. CCL will continue to vigorously prosecute the lawsuit. However, at this point, the Company is not able to determine the likelihood of any outcome in this matter. B. CEQA Lawsuit Against Los Angeles County Challenging Environmental Review for Landfill Expansion A separate lawsuit involving CCL and the Landfill was filed on August 24, 2017 by community activists alleging that the environmental review underlying the CUP was inadequate under state law. The Val Verde Civic Association, Citizens for Chiquita Canyon Landfill Compliance, and the Santa Clarita Organization for Planning the Environment filed a petition for writ of mandate in the Superior Court of California, County of Los Angeles against the County, naming CCL as the real party in interest. The lawsuit seeks to overturn the County’s approval of the CUP for the expansion of the Landfill and the certification of the final Environmental Impact Report, arguing that the report violates the California Environmental Quality Act. Pursuant to Condition No. 6 of the CUP, which requires CCL to defend, indemnify, and hold harmless the County, its agents, officers, and employees from any claim or proceeding against the County brought by any third party to attack, set aside, void, or annul the CUP approval, CCL has agreed to reimburse the County for its legal costs associated with defense of the lawsuit. As the real party in interest, CCL has a right to notice and an opportunity to be heard in opposition to the petition for writ of mandate. The petitioners filed their Opening Brief with the court on September 27, 2018. CCL filed its Opposition Brief with the court on November 28, 2018 and the petitioners filed their Reply Brief on December 20, 2018. A trial date had been scheduled for February 8, 2019, but on February 6, 2019, the court reassigned the case to a different judge and vacated the trial date. A new trial date was scheduled for August 23, 2019. At the conclusion of oral argument on August 23, 2019, the court asked the parties to return on September 13, 2019 for further oral argument on the odor mitigation issue. The court issued a final ruling on October 10, 2019 and a final judgment on December 4, 2019, denying the writ petition in full. On December 6, 2019, one of the petitioners, Santa Clarita Organization for Planning the Environment, filed an appeal of the court’s October 10, 2019 ruling. On December 9, 2019, the same petitioner filed an appeal of the court’s December 4, 2019 judgment. C. December 11, 2017 Notice of Violation Regarding Certain CUP Conditions. The County, through its DRP, issued a Notice of Violation, dated December 11, 2017 (the “NOV”), alleging that CCL violated certain conditions of the CUP, including Condition 79(B)(6) of the CUP by failing to pay an $11,600 Bridge & Thoroughfare Fee (“B&T Fee”) that was purportedly due on July 25, 2017. The alleged B&T fee was ostensibly to fund the construction of transportation infrastructure in the area of the Landfill. At the time the NOV was issued, CCL had already contested the legality of the B&T fee in the October 20, 2017 Complaint filed against the County in Los Angeles County Superior Court. 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, dated July 10, 2018, was received by CCL on July 12, 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 June 22, 2018, Chiquita filed a Motion for Stay seeking to halt enforcement of the B&T fee and penalty and the accrual of any further penalties pending the resolution of the Petition for Writ of Mandamus. The motion was heard and denied by the Court on July 17, 2018. As explained above, the Court granted CCL leave to pay the $11,600 B&T fee and to amend its Complaint to reflect the payment under protest, allowing the challenge to the B&T fee to proceed. CCL paid the B&T fee on August 10, 2018, and also paid on that date the administrative penalty of $83 and a noncompliance fee of $0.75. As directed by the Court, CCL amended its Complaint in a Second Amended Complaint filed in the CUP action on August 16, 2018. The Court indicated that the NOV case would likely be tried in conjunction with the CUP case, set for June 18, 2019, and that the cases would be coordinated. At the May 28, 2019 trial setting conference referenced above where the trial of the CUP case was set for April 23, 2020, the Superior Court set the trial for the B&T fee/NOV case for June 25, 2020. CCL will continue to vigorously prosecute the lawsuit. However, at this point, the Company is not able to determine the likelihood of any outcome in this matter. Town of Colonie, New York Landfill Expansion Litigation On April 16, 2014, the Town of Colonie (the “Town”) filed an application (the “Application”) with the New York State Department of Environmental Conservation (“DEC”) to modify the Town’s then-current Solid Waste Management Facility Permit and for other related permits to authorize the development and operation of Area 7 of the Town of Colonie Landfill (the “Landfill”), which is located in Albany County, New York. DEC issued the requested permits on April 5, 2018 (the “Permits”). The Company’s subsidiary, Capital Region Landfills, Inc. (“CRL”), has been the sole operator of the Landfill since September 2011 pursuant to an operating agreement between CRL and the Town. On May 7, 2018, the Town of Halfmoon, New York, and five of its residents, commenced an Article 78 special proceeding in the Supreme Court of the State of New York, Saratoga County, against DEC, the Town, CRL, and the Company (the “Halfmoon Proceeding”). On that same date, the Town of Waterford, New York, and eleven of its residents, also commenced an Article 78 special proceeding in the Supreme Court of the State of New York, Saratoga County, against the same respondents (the “Waterford Proceeding”). On June 4, 2018, the Town and CRL filed Verified Answers, including motions to dismiss the petitions, and the Company separately moved to dismiss the petitions. The Waterford Petitioners stipulated to removing the Company as a respondent when they filed an Amended Verified Petition on June 15, 2018. The Halfmoon Petitioners served an Amended Verified Petition on July 5, 2018, retaining all originally named parties, including the Company. The Petitioners alleged that, in granting the Permits, DEC failed to comply with the procedural and substantive requirements of New York’s Environmental Conservation Law and State Environmental Quality Review Act, and their implementing regulations. The Petitioners asked the court to: annul the Permits and invalidate DEC’s Findings Statement, enjoin the Town and CRL from taking any action authorized by the Permits, require an issues conference and possibly an adjudicatory hearing before DEC can re-consider the Town’s permit application; remand all regulatory issues to a DEC Administrative Law Judge; and award costs and disbursements. The Waterford Petitioners also requested reasonable attorneys’ fees. On July 13, 2018, the Honorable Ann C. Crowell granted a venue change motion filed by DEC, and ordered that the Halfmoon Proceeding and the Waterford Proceeding be transferred to the Supreme Court, Albany County. CRL’s opposition submissions, including its responsive pleadings, Memorandum of Law, and supporting Affidavits, were filed and served on or before July 25, 2018. On August 28, 2018, the Towns of Waterford and Halfmoon filed a motion seeking an order preliminarily enjoining during the pendency of the proceedings all activities relating to the expansion of the Landfill which are authorized by the Permits. On September 18, 2018, CRL and the Company filed and served Memoranda of Law in opposition to the preliminary injunction motion, with supporting Affidavits, and, on September 24, 2018, the Towns of Waterford and Halfmoon filed a Reply Memorandum of Law in further support of their injunctive motion. The Honorable Debra J. Young denied the Petitioners’ motion for preliminary injunction on November 30, 2018. On January 23, 2019, the court held that the Petitioners lacked standing to maintain the proceedings and dismissed both the Waterford and Halfmoon Amended Verified Petitions in their entirety. In late February and early March 2019, the Waterford and Halfmoon Petitioners filed notices of appeal to the Appellate Division, Third Department, of both Judge Crowell’s decision to transfer the proceedings to Albany County and of Judge Young’s dismissal of the Amended Verified Petitions. On March 7, 2019, the Waterford Petitioners moved, with consent of the Halfmoon Petitioners, to consolidate the appeals. Respondents opposed the consolidation motion to the extent that it may result in inequitable briefing under the Appellate Division rules. On April 4, 2019, the Appellate Division, Third Department granted the consolidation motion “to the extent that the appeals shall be heard together and may be perfected upon a joint record on appeal.” On April 26, 2019, the Waterford Petitioners filed a motion with the Appellate Division, Third Department, seeking an order preliminarily enjoining construction activities or the acceptance of waste at the Landfill. The Company, CRL, and the Town of Colonie opposed the motion, which was summarily denied by the Third Department, Appellate Division on June 20, 2019. On June 25, 2019, the Waterford Petitioners filed their appellate brief and the joint record on appeal. The Halfmoon Petitioners filed their appellate brief on August 21, 2019. The Company, CRL, and the Town filed their joint appellee brief and supplemental appendix on November 20, 2019. On January 8, 2020, the Office of the Attorney General of the State of New York filed a motion seeking a 45-day extension of the date by which DEC is required to file its appellee brief, which was granted. Its brief is now due by February 25, 2020. The Waterford and Halfmoon Petitioners’ reply briefs will be due ten days from service of DEC’s appellee brief. Collective Bargaining Agreements Twenty-one of the Company’s collective bargaining agreements have expired or are set to expire in 2020. The Company does not expect any significant disruption in its overall business in 2020 as a result of labor negotiations, employee strikes or organizational efforts.

Shareholders' Equity

Shareholders' Equity	12 Months Ended
	Dec. 31, 2019
Shareholders' Equity [Abstract]
Shareholders' Equity	13. SHAREHOLDERS’ EQUITY Share split On April 26, 2017, the Company announced that its Board of Directors approved a split of its common shares on a three Cash Dividend The Board of Directors authorized the initiation of a quarterly cash dividend in October 2010 and has increased it on an annual basis. In October 2019, the Company announced that its Board of Directors increased its regular quarterly cash dividend by $0.025, from $0.16 to $0.185 per Company common share. Cash dividends of $175,067, $152,550 and $131,975 were paid during the years ended December 31, 2019, 2018 and 2017, respectively. Normal Course Issuer Bid On July 25, 2019, the Board of Directors of the Company approved, subject to receipt of regulatory approvals, the annual renewal of the Company’s normal course issuer bid (the “NCIB”) to purchase up to 13,184,474 of the Company’s common shares during the period of August 8, 2019 to August 7, 2020 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 7, 2019. The Company received Toronto Stock Exchange (the “TSX”) approval for its annual renewal of the NCIB on August 2, 2019. Under the NCIB, the Company may make share repurchases only in the open market, including on the NYSE, the TSX, and/or alternative Canadian trading systems, at the prevailing market price at the time of the transaction. In accordance with TSX rules, any daily repurchases made through the TSX and alternative Canadian trading systems is limited to a maximum of 79,933 common shares, which represents 25% of the average daily trading volume on the TSX of 319,734 common shares for the period from February 1, 2019 to July 31, 2019. The TSX rules also allow the Company to purchase, once a week, a block of common shares not owned by any insiders, which may exceed such daily limit. The maximum number of shares that can be purchased per day on the NYSE will be 25% of the average daily trading volume for the four calendar weeks preceding the date of purchase, subject to certain exceptions for block purchases. The timing and amounts of any repurchases pursuant to the NCIB will depend on many factors, including the Company’s capital structure, the market price of the common shares and overall market conditions. All common shares purchased under the NCIB will be immediately cancelled following their repurchase. For the year ended December 31, 2019, the Company did not repurchase any common shares pursuant to the NCIB in effect during that period. For the year ended December 31, 2018, the Company repurchased 831,704 common shares pursuant to its NCIB in effect during such period at an aggregate cost of $58,928. For the year ended December 31, 2017, the Company did not repurchase any common shares pursuant to the NCIB in effect during that period. As of December 31, 2019, the remaining maximum number of shares available for repurchase under the current NCIB was 13,184,474. 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, 2019, the Company has reserved the following common shares for issuance: ​ ​ ​ ​ For outstanding RSUs, PSUs and warrants 1,991,919 For future grants under the 2016 Incentive Award Plan 5,431,669 ​ 7,423,588 ​ Common Shares Held in Trust Common shares held in trust at December 31, 2019 consist of 81,514 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, 2019, 2018 and 2017, the Company sold 48,375, 36,244 and 171,264 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, 2019, 2018 and 2017, no 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, 2019, 2018 and 2017, no Restricted Share Units, Performance-Based Restricted Share Units, Share Options and Share Purchase Warrants In connection with the Progressive Waste acquisition, each Waste Connections US, Inc. restricted stock unit award, deferred restricted stock unit award and warrant outstanding immediately prior to the Progressive Waste acquisition was automatically converted into a restricted share unit award, deferred restricted share unit award or warrant, as applicable, relating to an equal number of common shares of the Company, on the same terms and conditions as were applicable immediately prior to the Progressive Waste acquisition under such equity award. Such conversion of equity awards was approved by the Company’s shareholders at its shareholder meeting as part of the shareholders’ approval of the Progressive Waste acquisition. At its meeting on June 1, 2016, the Company’s Board of Directors approved the assumption by the Company of the Waste Connections US, Inc. 2014 Incentive Plan Award (the “2014 Plan”), the Waste Connections US, Inc. Third Amended and Restated 2004 Equity Incentive Plan (the “2004 Plan”), and the Waste Connections US, Inc. Consultant Incentive Plan (the “Consultant Plan,” and, together with the 2014 Plan and the 2004 Plan, the “Assumed Plans”) for the purposes of administering the Assumed Plans and the awards issued thereunder. No additional awards will be made under any of the Assumed Plans. Upon the vesting, expiration, exercise in accordance with their terms or other settlement of all of the awards made pursuant to an Assumed Plan, such Assumed Plan shall automatically terminate. Participation in the 2004 Plan was limited to employees, officers, directors and consultants. Restricted share units (“RSUs”) granted under the 2004 Plan generally vest in installments pursuant to a vesting schedule set forth in each agreement. The Board of Directors authorized the granting of awards under the 2004 Plan, and determined the employees and consultants to whom such awards were to be granted, the number of shares subject to each award, and the exercise price, term, vesting schedule and other terms and conditions of each award. RSU awards granted under the plan did not require any cash payment from the participant to whom an award was made. No The 2014 Plan also authorized the granting of RSUs, as well as performance awards payable in the form of the Company’s common shares or cash, including equity awards and incentive cash bonuses that may have been intended to qualify as “performance-based compensation” under Section 162(m) of the Internal Revenue Code of 1986, as amended (“Section 162(m)”). Participation in the 2014 Plan was limited to employees and consultants of the Company and its subsidiaries and non-employee directors. The 2014 Plan is administered by the Company’s Board of Directors with respect to awards to non-employee directors and by its Compensation Committee with respect to other participants, each of which may delegate its duties and responsibilities to committees of the Company’s directors and/or officers, subject to certain limitations (collectively, the “administrator”). RSUs granted under the 2014 Plan generally vest in installments pursuant to a vesting schedule set forth in each award agreement. RSU awards under the 2014 plan do not require any cash payment from the participant to whom an award was made. The vesting of performance awards, including performance-based restricted share units (“PSUs”), was dependent on one or more performance criteria determined by the administrator on a specific date or dates or over any period or periods determined by the administrator. On June 1, 2016, the Company’s Board of Directors adopted the 2016 Incentive Award Plan (the “2016 Plan”), which was approved by Progressive Waste’s shareholders on May 26, 2016. On each of July 24, 2017 and 2018, the Board of Directors approved certain housekeeping amendments to the 2016 Plan. The 2016 Plan, as amended, is administered by the Company’s Compensation Committee and provides that the aggregate number of common shares which may be issued from treasury pursuant to awards made under the 2016 Plan is 7,500,000 common shares. Awards under the 2016 Plan may be made to employees, consultants and non-employee directors and may be made in the form of options, warrants, restricted shares, restricted share units, performance awards (which may be paid in cash, common shares, or a combination thereof), dividend equivalent awards (representing a right of the holder thereof to receive the equivalent value (which may be paid in cash or common shares) of dividends paid on common shares), and share payments (a payment in the form of common shares or an option or other right to purchase common shares as part of a bonus, defined compensation or other arrangement). Non-employee directors are also eligible to receive deferred share units, which represent the right to receive a cash payment or its equivalent in common shares (or a combination of cash and common shares), or which may at the time of grant be expressly limited to settlement only in cash and not in common shares. Restricted Share Units A summary of the Company’s RSU activity is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 Weighted average grant-date fair value of restricted share units granted ​ $ 81.24 ​ $ 69.22 ​ $ 57.09 Total fair value of restricted share units vested ​ $ 21,136 ​ $ 18,795 ​ $ 16,715 ​ A summary of activity related to RSUs during the year ended December 31, 2019, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ Grant Date Fair ​ Unvested Shares ​ Value Per Share Outstanding at December 31, 2018 987,563 ​ $ 56.43 Granted 345,127 ​ $ 81.24 Forfeited (54,987) ​ $ 66.73 Vested and issued (416,691) ​ $ 50.72 Outstanding at December 31, 2019 861,012 ​ $ 68.47 ​ 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, 2019, 2018 and 2017, the Company had 247,999, 264,374 and 351,570 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, ​ 2019 2018 2017 Weighted average grant-date fair value of PSUs granted ​ $ 80.85 ​ $ 68.77 ​ $ 56.55 Total fair value of PSUs vested ​ $ 7,683 ​ $ 5,886 ​ $ 4,098 ​ A summary of activity related to PSUs during the year ended December 31, 2019, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ Grant Date Fair ​ Unvested Shares ​ Value Per Share Outstanding at December 31, 2018 532,086 ​ $ 53.43 Granted 152,656 ​ $ 80.85 Vested and issued (180,258) ​ $ 42.62 Outstanding at December 31, 2019 504,484 ​ $ 65.59 ​ During the year ended December 31, 2019, 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, 2021. During the same period, the Company’s Compensation Committee also granted PSUs with a one-year performance-based metric that the Company must meet before those awards may be earned, with the awards then subject to time-based vesting for the remaining three years of their four-year vesting period. During the year ended December 31, 2018, 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, 2020. During the same period, the Company’s Compensation Committee also granted PSUs with a one-year performance-based metric that the Company was required to meet before those awards were earned, with the awards then subject to time-based vesting for the remaining three years of their four-year vesting period. During the year ended December 31, 2017, 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, 2019. During the same period, the Company’s Compensation Committee also granted PSUs with a one-year performance-based metric that the Company was required to meet before those awards were earned, with the awards then subject to time-based vesting for the remaining three years of their four-year vesting period. The Compensation Committee determines the achievement of performance results and corresponding vesting of PSUs for each performance period. Share Purchase Warrants The Company has outstanding share purchase warrants issued under the 2014 Plan and 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, 2019, expire between 2020 and 2024. A summary of warrant activity during the year ended December 31, 2019, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ Warrants ​ Exercise Price Outstanding at December 31, 2018 268,211 ​ $ 63.49 Granted 151,008 ​ $ 91.43 Forfeited (15,728) ​ $ 35.05 Exercised (25,067) ​ $ 33.38 Outstanding at December 31, 2019 378,424 ​ $ 77.81 ​ The following table summarizes information about warrants outstanding as of December 31, 2019 and 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value of ​ ​ ​ ​ ​ ​ Warrants ​ ​ ​ Warrants ​ Outstanding at December 31, Grant Date ​ Issued ​ Exercise Price ​ Issued ​ 2019 ​ 2018 Throughout 2014 75,604 ​ $30.41 to $32.71 276 — 15,416 Throughout 2015 136,768 ​ $28.30 to $36.32 1,333 21,515 45,978 Throughout 2016 15,666 ​ $42.22 to $51.55 189 7,158 7,440 Throughout 2017 35,382 ​ $53.65 to $69.96 595 35,382 35,382 Throughout 2018 163,995 ​ $70.91 to $80.90 2,591 163,361 163,995 Throughout 2019 ​ 151,008 ​ $74.25 to $95.61 ​ 2,634 ​ 151,008 ​ — ​ ​ ​ ​ ​ 378,424 268,211 ​ Deferred Share Units A summary of the Company’s deferred share units (“DSUs”) activity is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 ​ 2018 2017 Weighted average grant-date fair value of DSUs granted ​ $ 83.80 ​ $ 70.47 ​ $ 57.65 Total fair value of DSUs awarded ​ $ 319 ​ $ 285 ​ $ 272 ​ 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, 2019, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ Grant Date Fair ​ Vested Shares ​ Value Per Share Outstanding at December 31, 2018 17,176 ​ $ 48.24 Granted 3,804 ​ $ 83.80 Cash settled (2,010) ​ $ 68.83 Outstanding at December 31, 2019 18,970 ​ $ 53.19 ​ Other Restricted Share Units RSU grants outstanding under the Progressive Waste share-based compensation plans were continued by the Company following the Progressive Waste acquisition and allow for the issuance of shares or cash settlement to employees upon vesting. A summary of activity related to Progressive Waste RSUs during the year ended December 31, 2019, is presented below: ​ ​ ​ ​ Outstanding at December 31, 2018 122,259 Cash settled (46,023) Forfeited (2,352) Outstanding at December 31, 2019 73,884 ​ A summary of vesting activity related to Progressive Waste RSUs during the year ended December 31, 2019, is presented below: ​ ​ ​ ​ Vested at December 31, 2018 120,153 Vested over remaining service period 2,106 Cash settled (46,023) Forfeited (2,352) Vested at December 31, 2019 73,884 ​ No Other Performance-Based Restricted Share Units PSU grants outstanding under the Progressive Waste share-based compensation plans were continued by the Company following the Progressive Waste acquisition and allow for cash settlement only to employees upon vesting based on achieving target results. A summary of activity related to Progressive Waste PSUs during the year ended December 31, 2019, is presented below: ​ ​ ​ ​ Outstanding at December 31, 2018 22,791 Cash settled, net of notional dividend (22,791) Outstanding at December 31, 2019 — ​ No PSUs under the Progressive Waste share-based compensation plans were granted subsequent to June 1, 2016. All outstanding PSUs were vested as of December 31, 2018. Share Based Options Share based options outstanding under the Progressive Waste share-based compensation plans were continued by the Company following the Progressive Waste acquisition and allow for the issuance of shares or cash settlement to employees upon vesting. A summary of activity related to Progressive Waste share based options during the year ended December 31, 2019, is presented below: ​ ​ ​ ​ Outstanding at December 31, 2018 165,156 Cash settled (38,995) Outstanding at December 31, 2019 126,161 ​ No share based options under the Progressive Waste share-based compensation plans were granted subsequent to June 1, 2016. All outstanding share based options were vested as of December 31, 2017.

Other Comprehensive Income (Los

Other Comprehensive Income (Loss)	12 Months Ended
	Dec. 31, 2019
Other Comprehensive Income (Loss) [Abstract]
Other Comprehensive Income (Loss)	14. OTHER COMPREHENSIVE INCOME (LOSS) Other comprehensive income (loss) includes changes in the fair value of interest rate swaps and fuel hedges that qualify for hedge accounting. The components of other comprehensive income (loss) and related tax effects for the years ended December 31, 2019, 2018 and 2017, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2019 ​ Gross Tax Effect Net of Tax Interest rate swap amounts reclassified into interest expense ​ $ (8,027) ​ $ 2,127 ​ $ (5,900) Changes in fair value of interest rate swaps ​ (43,873) ​ 11,626 ​ (32,247) Foreign currency translation adjustment ​ 101,970 ​ — ​ 101,970 ​ ​ $ 50,070 ​ $ 13,753 ​ $ 63,823 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2018 ​ Gross Tax Effect Net of Tax Interest rate swap amounts reclassified into interest expense ​ $ (5,669) ​ $ 1,502 ​ $ (4,167) Fuel hedge amounts reclassified into cost of operations ​ (6,531) ​ 1,627 ​ (4,904) Changes in fair value of interest rate swaps ​ (1,213) ​ 321 ​ (892) Changes in fair value of fuel hedge ​ 2,651 ​ (654) ​ 1,997 Foreign currency translation adjustment ​ (175,233) ​ — ​ (175,233) ​ ​ $ (185,995) ​ $ 2,796 ​ $ (183,199) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2017 ​ Gross Tax Effect Net of Tax Interest rate swap amounts reclassified into interest expense ​ $ 2,805 ​ $ (743) ​ $ 2,062 Fuel hedge amounts reclassified into cost of operations ​ 2,818 ​ (706) ​ 2,112 Changes in fair value of interest rate swaps ​ 7,835 ​ (4,040) ​ 3,795 Changes in fair value of fuel hedges ​ 1,326 ​ (367) ​ 959 Foreign currency translation adjustment ​ ​ 142,486 ​ ​ — ​ ​ 142,486 ​ ​ $ 157,270 ​ $ (5,856) ​ $ 151,414 ​ A roll forward of the amounts included in AOCIL, net of taxes, is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Foreign Accumulated ​ ​ ​ ​ ​ ​ ​ ​ Currency ​ Other ​ ​ ​ ​ ​ Interest ​ Translation ​ Comprehensive ​ ​ Fuel Hedges ​ Rate Swaps ​ Adjustment ​ Income (Loss) Balance at December 31, 2017 ​ $ 2,907 ​ $ 13,951 ​ $ 91,555 ​ $ 108,413 Amounts reclassified into earnings ​ (4,904) ​ (4,167) ​ — ​ (9,071) Changes in fair value ​ 1,997 ​ (892) ​ — ​ 1,105 Foreign currency translation adjustment ​ — ​ — ​ (175,233) ​ (175,233) Balance at December 31, 2018 ​ ​ — ​ ​ 8,892 ​ ​ (83,678) ​ ​ (74,786) Amounts reclassified into earnings ​ ​ — ​ ​ (5,900) ​ ​ — ​ ​ (5,900) Changes in fair value ​ ​ — ​ ​ (32,247) ​ ​ — ​ ​ (32,247) Foreign currency translation adjustment ​ ​ — ​ ​ — ​ ​ 101,970 ​ ​ 101,970 Balance at December 31, 2019 ​ $ — ​ $ (29,255) ​ $ 18,292 ​ $ (10,963) ​

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2019
Income Taxes [Abstract]
Income Taxes	15. 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, ​ 2019 2018 2017 U.S. ​ $ 477,203 ​ $ 491,506 ​ $ 301,962 Non – U.S. ​ 228,688 ​ 215,634 ​ 206,548 Income before income taxes ​ $ 705,891 ​ $ 707,140 ​ $ 508,510 ​ The provision (benefit) for income taxes for the years ended December 31, 2019, 2018 and 2017, consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 Current: ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. Federal ​ $ 45,475 ​ $ 37,419 ​ $ 45,089 State ​ 27,528 ​ 27,057 ​ 19,848 Non – U.S. ​ 11,570 ​ 17,651 ​ 18,537 ​ ​ 84,573 ​ 82,127 ​ 83,474 Deferred: ​ ​ ​ U.S. Federal ​ 58,291 ​ 85,926 ​ (203,131) State ​ 6,331 ​ 1,991 ​ 7,534 Non – U.S. ​ (9,985) ​ (10,058) ​ 43,213 ​ ​ 54,637 ​ 77,859 ​ (152,384) Provision (benefit) for income taxes ​ $ 139,210 ​ $ 159,986 ​ $ (68,910) ​ 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 (benefit) as presented in the accompanying Consolidated Statements of Net Income and income tax provision (benefit) computed at the federal statutory rate is presented on the basis of the U.S. federal statutory income tax rate of 21%for the years ended December 31, 2019 and 2018 and 35% for the year ending December 31, 2017, 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, ​ 2019 2018 2017 U.S. federal statutory rate ​ 21.0 % 21.0 % 35.0 % State taxes, net of federal benefit 4.4 4.4 4.1 ​ Deferred income tax liability adjustments 0.6 (0.2) 0.5 ​ Effect of international operations (6.3) (3.9) (14.6) ​ Enactment of the Tax Act — — (53.1) ​ Deferred tax on undistributed earnings — 0.9 12.3 ​ Goodwill impairment — — 2.1 ​ Other — 0.4 0.1 ​ ​ 19.7 % 22.6 % (13.6) % ​ The comparability of the Company’s income tax provision (benefit) for the reported periods has been affected by variations in its income before income taxes. The effects of international operations are primarily due to the Company’s non-U.S. income being taxed at rates substantially lower than the U.S. federal statutory rate for the year ended December 31, 2017, as well as a portion of the Company’s income from internal financing that is taxed at effective rates substantially lower than the U.S. federal statutory rate for each of the years presented. Additionally, for the year ended December 31, 2019, a reduction in deferred income tax assets primarily related to compensation of executive officers no longer deemed deductible for tax purposes resulted in an increase to tax expense of $3,805. For the year ended December 31, 2018, the restructuring of the Company’s internal refinancing in conjunction with the Tax Act resulted in an increase to tax expense of $5,572. Further, a reduction in the Company’s deferred income tax liabilities due to enacted state legislation and changes in the Company’s geographical apportionment due to acquisition activity resulted in a tax benefit of $3,057. During the year ended December 31, 2017, in conjunction with the Tax Act, the Company recorded a provisional deferred income tax expense of $62,350 associated with a portion of its U.S. earnings no longer permanently reinvested. During the year ended December 31, 2018, the Company recorded a deferred income tax expense of $6,429 associated with refinements to the prior year estimate as a measurement period adjustment pursuant to Staff Accounting Bulletin No. 118. This resulted in total deferred income tax expense of $68,779 which has been considered to be complete. During the year ended December 31, 2017, as a result of the enactment of the Tax Act, the Company recorded a net deferred income tax benefit of $269,804 primarily due to the reduction of the corporate income tax rate effective for tax years beginning in 2018. Additionally, the goodwill impairment within the E&P segment and disposal of goodwill from the divesture of certain operations, resulted in the write off of goodwill that was not deductible for tax purposes resulting in an increase to tax expense of $11,825. The significant components of deferred income tax assets and liabilities, reduced by valuation allowances as applicable, as of December 31, 2019 and 2018 are presented below. ​ ​ ​ ​ ​ ​ ​ ​ ​ 2019 2018 Deferred income tax assets: ​ ​ Accrued expenses ​ $ 23,536 ​ $ 26,128 Compensation ​ 17,532 ​ 19,830 Contingent liabilities ​ 15,228 ​ 14,043 Finance costs ​ — ​ 2,329 Tax credits and loss carryforwards ​ 18,693 ​ 20,438 Interest rate and fuel hedges ​ 10,548 ​ — Gross deferred income tax assets ​ 85,537 ​ 82,768 Less: Valuation allowance ​ — ​ — Total deferred income tax assets ​ 85,537 ​ 82,768 ​ ​ ​ ​ ​ ​ ​ Deferred income tax liabilities: ​ ​ ​ ​ ​ ​ Goodwill and other intangibles ​ (311,404) ​ (283,671) Property and equipment ​ (497,768) ​ (461,071) Landfill closure/post-closure ​ (12,159) ​ (8,892) Prepaid expenses ​ (8,542) ​ (11,581) Interest rate and fuel hedges ​ — ​ (3,206) Investment in subsidiaries ​ (69,597) ​ (69,383) Other ​ ​ (4,689) ​ ​ (4,997) Total deferred income tax liabilities ​ (904,159) ​ (842,801) Net deferred income tax liability ​ $ (818,622) ​ $ (760,033) ​ The Company has $29,460 of Canadian tax loss carryforwards with a 20-year carryforward period which will begin to expire in 2034, as well as various U.S. state tax losses with carryforward periods up to 20 years. As of December 31, 2019, the Company had undistributed earnings of approximately $2,609,805 for which income taxes have not been provided on permanently reinvested earnings of approximately $1,434,805. Additionally, the Company has not recorded deferred taxes on the amount of financial reporting basis in excess of tax basis of approximately $319,046 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 2015, except for the Progressive Waste U.S. federal income tax jurisdiction, which remains open for years subsequent to 2007. Additionally, the Company has concluded all Canadian income tax matters for years through 2014. The Company did not have any unrecognized tax benefits recorded at December 31, 2019, 2018 or 2017. The Company does not anticipate the total amount of unrecognized tax benefits will significantly change by December 31, 2020. 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, 2019
Segment Reporting [Abstract]
Segment Reporting	16. 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 five geographic solid waste operating segments and its E&P segment, which includes the majority of the Company’s E&P waste treatment and disposal operations. The Company’s five geographic solid waste operating segments and its E&P segment comprise the Company’s reportable segments. Each operating segment is responsible for managing several vertically integrated operations, which are comprised of districts. In the third quarter of 2017, the Company moved a district from the Eastern segment to the Canada segment as a significant amount of its revenues are received from Canadian-based customers. In the first quarter of 2019, the Company moved two districts from the Eastern segment to the Central segment because their locations in Iowa were closer in proximity to operations in the Company’s Central segment. The segment information presented herein reflects the realignment of these districts. Under the current orientation, the Company’s Eastern segment services customers located in northern Illinois, Kentucky, Maryland, Massachusetts, New Jersey, New York, North Carolina, Pennsylvania, Rhode Island, South Carolina, eastern Tennessee, Vermont, Virginia and Wisconsin; the Company’s Southern segment services customers located in Alabama, Arkansas, Florida, Georgia, Louisiana, Mississippi, southern Oklahoma, western Tennessee and Texas; the Company’s Western segment services customers located in Alaska, California, Idaho, Montana, Nevada, Oregon, Washington and western Wyoming; the Company’s Central segment services customers located in Arizona, Colorado, southern Illinois, Iowa, Kansas, Minnesota, Missouri, Nebraska, New Mexico, Oklahoma, South Dakota, western Texas, Utah and eastern Wyoming; and the Company’s Canada segment services customers located in the state of Michigan and in the provinces of Alberta, British Columbia, Manitoba, Ontario, Québec and Saskatchewan. The E&P segment services E&P customers located in Louisiana, New Mexico, North Dakota, Oklahoma, Texas, Wyoming and along the Gulf of Mexico. The Company’s Chief Operating Decision Maker evaluates operating segment profitability and determines resource allocations based on several factors, of which the primary financial measure is segment EBITDA. The Company defines segment EBITDA as earnings before interest, taxes, depreciation, amortization, impairments and other operating items, and other income (expense). Segment EBITDA is not a measure of operating income, operating performance or liquidity under generally accepted accounting principles and may not be comparable to similarly titled measures reported by other companies. The Company’s management uses segment EBITDA in the evaluation of segment operating performance as it is a profit measure that is generally within the control of the operating segments. A reconciliation of segment EBITDA to Income before income tax provision is included at the end of this Note 16. Summarized financial information concerning the Company’s reportable segments for the years ended December 31, 2019, 2018 and 2017, is shown in the following tables: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ Intercompany ​ Reported ​ Segment ​ Depreciation and ​ Capital ​ ​ ​ December 31, 2019 ​ Revenue ​ Revenue (b) ​ Revenue ​ EBITDA (c) ​ Amortization ​ Expenditures ​ Total Assets (e) Eastern ​ $ 1,524,648 ​ $ (255,684) ​ $ 1,268,964 ​ $ 330,578 ​ $ 204,221 ​ $ 154,218 ​ $ 3,099,283 Southern ​ ​ 1,355,753 ​ ​ (162,831) ​ ​ 1,192,922 ​ ​ 305,999 ​ ​ 160,038 ​ ​ 141,157 ​ ​ 2,990,247 Western ​ 1,234,669 ​ (135,820) ​ 1,098,849 ​ 338,563 ​ 102,067 ​ 147,893 ​ 1,718,015 Central ​ 958,139 ​ (119,555) ​ 838,584 ​ 292,111 ​ 106,391 ​ 116,831 ​ 1,885,468 Canada ​ 835,603 ​ (102,321) ​ 733,282 ​ 256,405 ​ 113,944 ​ 61,119 ​ 2,490,291 E&P ​ 267,861 ​ (11,783) ​ 256,078 ​ 135,426 ​ 48,929 ​ 36,970 ​ 962,202 Corporate (a), (d) ​ — ​ — ​ — ​ (15,438) ​ 8,328 ​ 7,901 ​ 592,189 ​ ​ $ 6,176,673 ​ $ (787,994) ​ $ 5,388,679 ​ $ 1,643,644 ​ $ 743,918 ​ $ 666,089 ​ $ 13,737,695 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ Intercompany ​ Reported ​ Segment ​ Depreciation and ​ Capital ​ ​ ​ December 31, 2018 ​ Revenue ​ Revenue (b) ​ Revenue ​ EBITDA (c) ​ Amortization ​ Expenditures ​ Total Assets (e) Eastern ​ $ 1,296,823 ​ $ (224,833) ​ $ 1,071,990 ​ $ 295,016 ​ $ 166,715 ​ $ 136,214 ​ $ 2,673,316 Southern ​ ​ 1,273,033 ​ ​ (150,485) ​ ​ 1,122,548 ​ ​ 276,791 ​ ​ 153,923 ​ ​ 97,442 ​ ​ 2,892,994 Western ​ 1,170,382 ​ (126,454) ​ 1,043,928 ​ 318,401 ​ 95,400 ​ 125,112 ​ 1,596,129 Central ​ 815,520 ​ (103,966) ​ 711,554 ​ 259,794 ​ 89,001 ​ 91,646 ​ 1,506,326 Canada ​ 823,989 ​ (96,776) ​ 727,213 ​ 261,233 ​ 124,155 ​ 66,319 ​ 2,412,971 E&P ​ 253,083 ​ (7,375) ​ 245,708 ​ 129,825 ​ 44,175 ​ 25,937 ​ 969,808 Corporate (a), (d) ​ — ​ — ​ — ​ (8,211) ​ 7,118 ​ 3,475 ​ 575,785 ​ ​ $ 5,632,830 ​ $ (709,889) ​ $ 4,922,941 ​ $ 1,532,849 ​ $ 680,487 ​ $ 546,145 ​ $ 12,627,329 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ Intercompany ​ Reported ​ Segment ​ Depreciation and ​ Capital ​ ​ ​ December 31, 2017 ​ Revenue ​ Revenue (b) ​ Revenue ​ EBITDA (c) ​ Amortization ​ Expenditures ​ Total Assets (e) Eastern ​ $ 1,120,221 ​ $ (178,394) ​ $ 941,827 ​ $ 269,106 ​ $ 135,737 ​ $ 100,025 ​ $ 2,009,328 Southern ​ 1,262,147 ​ (146,283) ​ 1,115,864 ​ 258,560 ​ 151,417 ​ 117,441 ​ 2,718,296 Western ​ 1,127,146 ​ (119,916) ​ 1,007,230 ​ 323,648 ​ 95,724 ​ 100,000 ​ 1,573,955 Central ​ 734,042 ​ (88,488) ​ 645,554 ​ 241,972 ​ 79,460 ​ 79,544 ​ 1,312,317 Canada ​ 828,755 ​ (99,978) ​ 728,777 ​ 264,693 ​ 121,174 ​ 62,690 ​ 2,677,557 E&P ​ 199,063 ​ (7,827) ​ 191,236 ​ 90,597 ​ 42,500 ​ 12,274 ​ 981,980 Corporate (a), (d) ​ — ​ — ​ — ​ (32,501) ​ 6,472 ​ 7,313 ​ 741,248 ​ ​ $ 5,271,374 ​ $ (640,886) ​ $ 4,630,488 ​ $ 1,416,075 ​ $ 632,484 ​ $ 479,287 ​ $ 12,014,681 (a) Corporate functions include accounting, legal, tax, treasury, information technology, risk management, human resources, training, direct acquisition expenses, other administrative functions and share-based compensation expenses associated with Progressive Waste share-based grants existing at June 1, 2016. Amounts reflected are net of allocations to the six operating segments. For the years ended December 31, 2018 and 2017, amounts also include Progressive Waste integration-related expenses. (b) Intercompany revenues reflect each segment’s total intercompany sales, including intercompany sales within a segment and between segments. Transactions within and between segments are generally made on a basis intended to reflect the market value of the service. (c) For those items included in the determination of segment EBITDA, the accounting policies of the segments are the same as those described in Note 3. (d) Corporate assets include cash, debt issuance costs, equity investments, operating lease right-of-use assets and corporate facility leasehold improvements and equipment. (e) Goodwill is included within total assets for each of the Company’s six operating segments. The following table shows changes in goodwill during the years ended December 31, 2018 and 2019, by reportable segment: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Eastern Southern Western Central Canada E&P Total Balance as of December 31, 2017 ​ $ 804,133 ​ $ 1,436,320 ​ $ 397,508 ​ $ 468,275 ​ $ 1,575,538 ​ $ — ​ $ 4,681,774 Goodwill transferred ​ ​ (16,869) ​ ​ — ​ ​ — ​ ​ 16,869 ​ ​ — ​ ​ — ​ ​ — Goodwill acquired ​ 339,222 ​ 71,109 ​ 666 ​ 55,291 ​ 153 ​ — ​ 466,441 Goodwill adjustment for assets sold ​ — ​ 10,181 ​ — ​ — ​ — ​ — ​ 10,181 Impact of changes in foreign currency ​ — ​ — ​ — ​ — ​ (126,711) ​ — ​ (126,711) Balance as of December 31, 2018 ​ ​ 1,126,486 ​ ​ 1,517,610 ​ ​ 398,174 ​ ​ 540,435 ​ ​ 1,448,980 ​ ​ — ​ ​ 5,031,685 Goodwill acquired ​ 204,694 ​ 11,460 ​ ​ 1,863 ​ 189,035 ​ ​ 16 ​ ​ — ​ 407,068 Goodwill divested ​ — ​ (845) ​ — ​ — ​ — ​ — ​ (845) Impact of changes in foreign currency ​ — ​ — ​ — ​ — ​ 72,943 ​ — ​ 72,943 Balance as of December 31, 2019 ​ $ 1,331,180 ​ $ 1,528,225 ​ $ 400,037 ​ $ 729,470 ​ $ 1,521,939 ​ $ — ​ $ 5,510,851 ​ Property and equipment, net relating to operations in the United States and Canada are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2019 2018 United States ​ $ 4,862,557 ​ $ 4,516,966 Canada ​ 653,790 ​ 652,030 Total ​ $ 5,516,347 ​ $ 5,168,996 ​ A reconciliation of the Company’s primary measure of segment profitability (segment EBITDA) to Income before income tax provision in the Consolidated Statements of Net Income is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years ended December 31, ​ 2019 2018 2017 Eastern segment EBITDA ​ $ 330,578 ​ $ 295,016 ​ $ 269,106 Southern segment EBITDA ​ ​ 305,999 ​ ​ 276,791 ​ ​ 258,560 Western segment EBITDA ​ 338,563 ​ 318,401 ​ 323,648 Central segment EBITDA ​ 292,111 ​ 259,794 ​ 241,972 Canada segment EBITDA ​ 256,405 ​ 261,233 ​ 264,693 E&P segment EBITDA ​ 135,426 ​ 129,825 ​ 90,597 Subtotal reportable segments ​ 1,659,082 ​ 1,541,060 ​ 1,448,576 Unallocated corporate overhead ​ (15,438) ​ (8,211) ​ (32,501) Depreciation ​ (618,396) ​ (572,708) ​ (530,187) Amortization of intangibles ​ (125,522) ​ (107,779) ​ (102,297) Impairments and other operating items ​ (61,948) ​ (20,118) ​ (156,493) Interest expense ​ (147,368) ​ (132,104) ​ (125,297) Interest income ​ 9,777 ​ 7,170 ​ 5,173 Other income (expense), net ​ 5,704 ​ (170) ​ 1,536 Income before income tax provision ​ $ 705,891 ​ $ 707,140 ​ $ 508,510 ​

Net Income Per Share Informatio

Net Income Per Share Information	12 Months Ended
	Dec. 31, 2019
Net Income Per Share Information [Abstract]
Net Income Per Share Information	17. 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, 2019, 2018 and 2017: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 Numerator: ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income attributable to Waste Connections for basic and diluted earnings per share ​ $ 566,841 ​ $ 546,871 ​ $ 576,817 Denominator: ​ ​ ​ ​ ​ Basic shares outstanding ​ 263,792,693 ​ 263,650,155 ​ 263,682,608 Dilutive effect of equity-based awards ​ 733,868 ​ 745,463 ​ 619,803 Diluted shares outstanding ​ 264,526,561 ​ 264,395,618 ​ 264,302,411 ​

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2019
Employee Benefit Plans [Abstract]
Employee Benefit Plans	18. EMPLOYEE BENEFIT PLANS Retirement Savings Plans: Certain of Waste Connections’ subsidiaries also have voluntary savings and investment plans in the U.S. (the “401(k) Plans”). The 401(k) Plans are available to all eligible U.S. employees of Waste Connections and its subsidiaries. Waste Connections and its subsidiaries make matching contributions under the 401(k) Plans of 100% of every dollar of a participating employee’s pre-tax contributions until the employee’s contributions equal 5% of the employee’s eligible compensation, subject to certain limitations imposed by the U.S. Internal Revenue Code. Total employer expenses, including employer matching contributions, for the DPSP and 401(k) Plans were $26,111, $12,055 and $14,703, respectively, during the years ended December 31, 2019, 2018 and 2017. 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 ​ Bargaining Plan Name Number 2019 2018 (a),(b) 2019 2018 2017 Agreement Local 731, I.B. of T., Private Scavengers, Garage Attendants, and Textile Maintenance Pension Trust Fund 36-6513567 - 001 Green for the plan year ended 9/30/2019 Green for the plan year ended 9/30/2017 Not applicable ​ $ 4,570 ​ $ 4,600 ​ $ 4,342 9/30/2023 Western Conference of Teamsters Pension Trust 91-6145047 - 001 Green Green Not applicable ​ ​ 4,550 ​ ​ 4,399 ​ ​ 4,191 12/31/2019 to 7/31/2022 Suburban Teamsters of Northern Illinois Pension Fund 36-6155778 - 001 Green for the plan year beginning 1/1/2019 Yellow Not applicable ​ 1,844 ​ 1,569 ​ 877 1/31/2024 Teamster Local 301 Pension Fund 36-6492992 - 001 Green Green Not applicable ​ 624 ​ 581 ​ 489 9/30/2023 Automobile Mechanics’ Local No. 701 Union and Industry Pension Fund 36-6042061 - 001 Yellow Yellow Implemented ​ 492 ​ 484 ​ 837 12/31/2022 Midwest Operating Engineers Pension Plan 36-6140097 - 001 Green for the plan year beginning 4/1/2019 Yellow for the plan year ended 3/31/2017 Not applicable ​ 339 ​ 289 ​ 207 10/31/2020 Locals 302 & 612 of the IOUE - Employers Construction Industry Retirement Plan 91-6028571 - 001 Green Green Not applicable ​ 290 ​ 284 ​ 275 11/16/2022 Local 813 Pension Trust Fund 13-1975659 - 001 Critical Critical Implemented ​ 281 ​ 165 ​ 158 11/30/2019 IAM National Pension Fund ​ 51-6031295 - 002 ​ Green ​ Green ​ Not applicable ​ ​ 256 ​ ​ 240 ​ ​ 215 ​ 12/31/2022 International Union of Operating Engineers Pension Trust 85512-1 Green as of 4/30/2017 Green as of 4/30/2017 Not applicable ​ 238 ​ 224 ​ 219 3/31/2020 to 3/31/2021 Multi-Sector Pension Plan 1085653 Green as of 1/1/2019 Green Not applicable ​ 202 ​ 191 ​ 228 12/31/2018 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 13,686 ​ $ 13,026 ​ $ 12,038 ​ ​ ​ (a) Unless otherwise noted in the table above, the most recent Pension Protection Act zone status available in 2019 and 2018 is for the plans’ years ended December 31, 2018 and 2017, 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, 2019 and 2018. The status is based on information that the Company received from the pension plans and is certified by the pension plans’ actuary. Plans with “green” status are at least 80% funded. Plans with “yellow” status are less than 80% funded. Plans with “critical” status are less than 65% funded. The Company’s contributions to each individual multiemployer pension plan represent less than 5% of total contributions to such plan. 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: matching contributions under the Deferred Compensation Plan were 100% vested when made. The Company’s total liability for deferred compensation at December 31, 2019 and 2018 was $37,707 and $32,024, respectively, which was recorded in Other long-term liabilities in the Consolidated Balance Sheets.

Selected Quarterly Financial Da

Selected Quarterly Financial Data (Unaudited)	12 Months Ended
	Dec. 31, 2019
Selected Quarterly Financial Data [Abstract]
Selected Quarterly Financial Data (Unaudited)	19. SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) The following table summarizes the Company’s unaudited consolidated quarterly results of operations for 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ First Quarter Second Quarter Third Quarter Fourth Quarter Revenues ​ $ 1,244,637 ​ $ 1,369,639 ​ $ 1,412,444 ​ $ 1,361,960 Operating income ​ $ 184,860 ​ $ 222,134 ​ $ 236,600 ​ $ 194,184 Net income ​ $ 125,577 ​ $ 148,839 ​ $ 159,074 ​ $ 133,191 Net income attributable to Waste Connections ​ $ 125,622 ​ $ 148,848 ​ $ 159,109 ​ $ 133,262 Basic income per common share attributable to Waste Connections’ common shareholders ​ $ 0.48 ​ $ 0.56 ​ $ 0.60 ​ $ 0.51 Diluted income per common share attributable to Waste Connections’ common shareholders ​ $ 0.48 ​ $ 0.56 ​ $ 0.60 ​ $ 0.50 ​ During the first quarter of 2019, the Company recorded $12,230 of charges to terminate or write off the carrying cost of certain contracts, primarily acquired in the Progressive Waste acquisition, that were not, or are not expected to be, renewed prior to their original estimated termination date. During the third quarter of 2019, the Company recorded $8,000 resulting from the abandonment of a landfill development project at the Company’s E&P segment. During the fourth quarter of 2019, the Company recorded $25,798 of charges associated with the write-down of an operating permit and equipment at a non-strategic materials recovery facility that was disposed of by sale on January 2, 2020. The following table summarizes the Company’s unaudited consolidated quarterly results of operations for 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ First Quarter Second Quarter Third Quarter Fourth Quarter Revenues ​ $ 1,140,131 ​ $ 1,239,968 ​ $ 1,281,110 ​ $ 1,261,732 Operating income ​ $ 188,707 ​ $ 210,688 ​ $ 232,869 ​ $ 199,980 Net income ​ $ 125,032 ​ $ 138,814 ​ $ 150,766 ​ $ 132,543 Net income attributable to Waste Connections ​ $ 124,869 ​ $ 138,682 ​ $ 150,843 ​ $ 132,478 Basic income per common share attributable to Waste Connections’ common shareholders ​ $ 0.47 ​ $ 0.53 ​ $ 0.57 ​ $ 0.50 Diluted income per common share attributable to Waste Connections’ common shareholders ​ $ 0.47 ​ $ 0.52 ​ $ 0.57 ​ $ 0.50 ​ During the third quarter of 2018, the Company reversed $6,257 of expenses recognized in prior periods to adjust the carrying cost of assets held for disposal to fair market value due to modifications to its divestiture plan and changes in the fair market value of the divested operations. During the third quarter of 2018, the Company also recorded $5,005 in equity-based compensation expenses associated with adjusting common shares of Waste Connections, Inc. held in the Company’s deferred compensation plan by certain key executives to fair value as a result of the shares being exchanged for other investment options. During the fourth quarter of 2018, the Company recorded $11,043 for the potential settlement of a final judgment obtained against Progressive Waste Solutions of FL, Inc., now known as Waste Connections of Florida, Inc.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2019
Subsequent Events [Abstract]
Subsequent Events	20. SUBSEQUENT EVENTS On January 23, 2020, the Company completed an underwritten public offering of $600,000 aggregate principal amount of 2.60% Senior Notes due 2030 (the “2030 Senior Notes”). The 2030 Senior Notes were issued under the Indenture, dated as of November 16, 2018, by and between the Company and U.S. Bank National Association, as trustee, as supplemented by the Third Supplemental Indenture, dated as of January 23, 2020. The Company will pay interest on the Notes semi-annually in arrears and the Notes will mature on February 1, 2030. The Notes are the Company’s senior unsecured obligations, ranking equally in right of payment with its other existing and future unsubordinated debt and senior to any of its future subordinated debt. The Notes are not guaranteed by any of the Company’s subsidiaries. Net proceeds to the Company from the offering were used to repay a portion of the Company’s borrowings outstanding under its Credit Agreement and for general corporate purposes. On February 12, 2020, the Company announced that its Board of Directors approved a regular quarterly cash dividend of $0.185 per Company common share. The dividend will be paid on March 12, 2020, to shareholders of record on the close of business on February 27, 2020.

Valuation and Qualifying Accoun

Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2019
Valuation and Qualifying Accounts [Abstract]
Schedule II Valuation and Qualifying Accounts	WASTE CONNECTIONS, INC. SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS Years Ended December 31, 2019, 2018 and 2017 (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 Doubtful Accounts: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2019 ​ $ 16,760 ​ $ 11,973 ​ $ — ​ $ (12,301) ​ $ 16,432 Year Ended December 31, 2018 ​ $ 17,154 ​ $ 13,814 ​ $ — ​ $ (14,208) ​ $ 16,760 Year Ended December 31, 2017 ​ $ 13,160 ​ $ 14,363 ​ $ — ​ $ (10,369) ​ $ 17,154 ​

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2019
Business [Abstract]
Reporting Currency	Reporting Currency The functional currency of the Company, as the parent corporate entity, and its operating subsidiaries in the United States, is the U.S. dollar. The functional currency of the Company’s Canadian operations is the Canadian dollar. The reporting currency of the Company is the U.S. dollar. The Company’s consolidated Canadian dollar financial position is translated to U.S. dollars by applying the foreign currency exchange rate in effect at the consolidated balance sheet date. The Company’s consolidated Canadian dollar results of operations and cash flows are translated to U.S. dollars by applying the average foreign currency exchange rate in effect during the reporting period. The resulting translation adjustments are included in other comprehensive income or loss. Gains and losses from foreign currency transactions are included in earnings for the period.
Cash Equivalents	Cash Equivalents The Company considers all highly liquid investments with a maturity of three months or less at purchase to be cash equivalents. As of December 31, 2019 and 2018, 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 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, non-hazardous exploration and production (“E&P”) waste treatment, recovery and disposal services, and intermodal services. The following table disaggregates the Company’s revenues by service line for the periods indicated: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 Commercial $ 1,593,217 ​ $ 1,452,831 $ 1,343,590 Residential ​ ​ 1,380,763 ​ ​ 1,189,148 ​ ​ 1,130,842 Industrial and construction roll off ​ ​ 841,173 ​ ​ 768,687 ​ ​ 707,015 Total collection ​ ​ 3,815,153 ​ ​ 3,410,666 ​ ​ 3,181,447 Landfill ​ ​ 1,132,935 ​ ​ 1,063,243 ​ ​ 988,092 Transfer ​ ​ 771,316 ​ ​ 670,129 ​ ​ 589,883 Recycling ​ ​ 64,245 ​ ​ 92,634 ​ ​ 161,730 E&P ​ ​ 271,887 ​ ​ 256,262 ​ ​ 203,473 Intermodal and other ​ ​ 121,137 ​ ​ 139,896 ​ ​ 146,749 Intercompany ​ ​ (787,994) ​ ​ (709,889) ​ ​ (640,886) Total $ 5,388,679 ​ $ 4,922,941 $ 4,630,488 ​ 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 16 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 recognized as of September 30, 2019 was recognized as revenue during the three months ended December 31, 2019 when the service was performed. Commercial customers are typically billed on a monthly basis based on the nature of the services provided during the period. Revenue recognized under these agreements is variable in nature based on the number of residential homes or businesses serviced during the period, the frequency of collection and the volume of waste collected. In addition, certain contracts have annual price escalation clauses that are tied to changes in an underlying base index such as a consumer price index which are unknown at contract inception. Solid waste collection revenue from sources other than customer contracts primarily relates to lease revenue associated with compactors. Revenue from these leasing arrangements was not material and represented an insignificant amount of total revenue for each of the reported periods. Landfill and Transfer Station Revenue at landfills is primarily generated by charging tipping fees on a per ton and/or per yard basis to third parties based on the volume disposed and the nature of the waste. In general, fees are variable in nature and revenue is recognized at the time the waste is disposed at the facility. Revenue at transfer stations is primarily generated by charging tipping or disposal fees on a per ton and/or per yard basis. The fees charged to third parties are based primarily on the market, type and volume or weight of the waste accepted, the distance to the disposal facility and the cost of disposal. In general, fees are billed and revenue is recognized at the time the service is performed. Revenue recognized under these agreements is variable in nature based on the volume of waste accepted at the transfer facility. Many of the Company’s landfill and transfer station customers have entered into one Solid Waste Recycling Solid waste recycling revenues 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 recycling operations and markets collected recyclable materials to third parties for processing before resale. 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 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 including closed loop collection systems, the transportation of waste to the disposal facility in certain markets and the sale of recovered products. E&P activity varies across market areas that are tied to the natural resource basins in which the drilling activity occurs and reflects the regulatory environment, pricing and disposal alternatives available in any given market. 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 generated from the Company’s MSW landfills. Revenue Recognition Service obligations of a long-term nature, e.g., solid waste collection service contracts, are satisfied over time, and revenue is recognized based on the value provided to the customer during the period. The amount billed to the customer is based on variable elements such as the number of residential homes or businesses for which collection services are provided, the volume of waste collected, transported and disposed, and the nature of the waste accepted. The Company does not disclose the value of unsatisfied performance obligations for these contracts as its right to consideration corresponds directly to the value provided to the customer for services completed to date and all future variable consideration is allocated to wholly unsatisfied performance obligations. Additionally, certain elements of long-term customer contracts are unknown upon entering into the contract, including the amount that will be billed in accordance with annual price escalation clauses, fuel recovery fee programs and commodity prices. The amount to be billed is often tied to changes in an underlying base index such as a consumer price index or a fuel or commodity index, and revenue is recognized once the index is established for the period.
Accounts Receivable	Accounts Receivable Accounts receivable are recorded when billed or accrued and represent claims against third parties that will be settled in cash. The carrying value of the Company’s receivables, net of the allowance for doubtful accounts, represents their estimated net realizable value. The Company estimates its allowance for doubtful accounts based on historical collection trends, type of customer such as municipal or non-municipal, the age of outstanding receivables and existing economic conditions. If events or changes in circumstances indicate that specific receivable balances may be impaired, further consideration is given to the collectability of those balances and the allowance is adjusted accordingly. Past-due receivable balances are written off when the Company’s internal collection efforts have been unsuccessful in collecting the amount due.
Contract Acquisition Costs	Contract Acquisition Costs The incremental direct costs of obtaining a contract, which consist of sales incentives, are recognized as Other assets in the Company’s Consolidated Balance Sheet, and are amortized to Selling, general and administrative expense over the estimated life of the relevant customer relationship, which ranges from one
Property and Equipment	Property and Equipment Property and equipment are stated at cost. Improvements or betterments, not considered to be maintenance and repair, which add new functionality or significantly extend the life of an asset are capitalized. Third-party expenditures related to pending development projects, such as legal and engineering expenses, are capitalized. Expenditures for maintenance and repair costs, including planned major maintenance activities, are charged to expense as incurred. The cost of assets retired or otherwise disposed of and the related accumulated depreciation are eliminated from the accounts in the year of disposal. Gains and losses resulting from disposals of property and equipment are recognized in the period in which the property and equipment is disposed. Depreciation is computed using the straight-line method over the estimated useful lives of the assets or the lease term, whichever is shorter. The estimated useful lives are as follows: ​ ​ ​ ​ Buildings 10 Leasehold and land improvements 3 Machinery and equipment 3 Rolling stock 3 Containers 3
Landfill Accounting	Landfill Accounting The Company utilizes the life cycle method of accounting for landfill costs. This method applies the costs to be capitalized associated with acquiring, developing, closing and monitoring the landfills over the associated consumption of landfill capacity. The Company utilizes the units of consumption method to amortize landfill development costs over the estimated remaining capacity of a landfill. Under this method, the Company includes future estimated construction costs using current dollars, as well as costs incurred to date, in the amortization base. When certain criteria are met, the Company includes expansion airspace, which has not been permitted, in the calculation of the total remaining capacity of the landfill. - Landfill development costs Total landfill costs include the development costs associated with expansion airspace. Expansion airspace is addressed below. - Final capping, closure and post-closure obligations The net present value of landfill final capping, closure and post-closure liabilities are calculated by estimating the total obligation in current dollars, inflating the obligation based upon the expected date of the expenditure and discounting the inflated total to its present value using a credit-adjusted risk-free rate. Any changes in expectations that result in an upward revision to the estimated undiscounted cash flows are treated as a new liability and are inflated and discounted at rates reflecting current market conditions. Any changes in expectations that result in a downward revision (or no revision) to the estimated undiscounted cash flows result in a liability that is inflated and discounted at rates reflecting the market conditions at the time the cash flows were originally estimated. This policy results in the Company’s final capping, closure and post-closure liabilities being recorded in “layers.” The Company’s discount rate assumption for purposes of computing 2019 and 2018 “layers” for final capping, closure and post-closure obligations was 4.75% for both years, which reflects the Company’s long-term credit adjusted risk free rate as of the end of both 2018 and 2017. The Company’s inflation rate assumption was 2.5% for the years ended December 31, 2019 and 2018. In accordance with the accounting guidance on asset retirement obligations, the final capping, closure and post-closure liability is recorded on the balance sheet along with an offsetting addition to site costs which is amortized to depletion expense on a units-of-consumption basis as remaining landfill airspace is consumed. The impact of changes determined to be changes in estimates, based on an annual update, is accounted for on a prospective basis. Depletion expense resulting from final capping, closure and post-closure obligations recorded as a component of landfill site costs will generally be less during the early portion of a landfill’s operating life and increase thereafter. Owned landfills and landfills operated under life-of-site agreements have estimated remaining lives, based on remaining permitted capacity, probable expansion capacity and projected annual disposal volumes, that range from approximately 1 to 176 years, with an average remaining life of approximately 29 years. The costs for final capping, closure and post-closure obligations at landfills the Company owns or operates under life-of-site agreements are generally estimated based on interpretations of current requirements and proposed or anticipated regulatory changes. The following is a reconciliation of the Company’s final capping, closure and post-closure liability balance from December 31, 2017 to December 31, 2019: ​ ​ ​ ​ ​ Final capping, closure and post-closure liability at December 31, 2017 $ 237,817 Liabilities incurred ​ 2,640 Accretion expense associated with landfill obligations ​ 12,777 Closure payments ​ (2,731) Assumption of closure liabilities from acquisitions ​ 4,408 Foreign currency translation adjustment ​ ​ (3,129) Final capping, closure and post-closure liability at December 31, 2018 ​ 251,782 Liabilities incurred ​ 19,846 Accretion expense associated with landfill obligations ​ 14,251 Closure payments ​ (5,059) Assumption of closure liabilities from acquisitions ​ ​ 8,707 Foreign currency translation adjustment ​ 1,947 Final capping, closure and post-closure liability at December 31, 2019 ​ $ 291,474 ​ Liabilities incurred of $19,846 and $2,640 for the years ended December 31, 2019 and 2018, respectively, represent non-cash increases to final capping, closure and post-closure liabilities and are recorded on the Condensed Consolidated Balance Sheets along with an offsetting addition to site costs, which is amortized to depletion expense as the remaining landfill airspace is consumed. The final capping, closure and post-closure liability is included in Other long-term liabilities in the Consolidated Balance Sheets. The Company performs its annual review of its cost and capacity estimates in the first quarter of each year. - Disposal capacity 1) whether the land where the expansion is being sought is contiguous to the current disposal site, and the Company either owns the expansion property or has rights to it under an option, purchase, operating or other similar agreement; 2) whether total development costs, final capping costs, and closure/post-closure costs have been determined; 3) whether internal personnel have performed a financial analysis of the proposed expansion site and have determined that it has a positive financial and operational impact; 4) whether internal personnel or external consultants are actively working to obtain the necessary approvals to obtain the landfill expansion permit; and 5) whether the Company considers it probable that the Company will achieve the expansion (for a pursued expansion to be considered probable, there must be no significant known technical, legal, community, business, or political restrictions or similar issues existing that the Company believes are more likely than not to impair the success of the expansion). It is possible that the Company’s estimates or assumptions could ultimately be significantly different from actual results. In some cases, the Company may be unsuccessful in obtaining an expansion permit or the Company may determine that an expansion permit that the Company previously thought was probable has become unlikely. To the extent that such estimates, or the assumptions used to make those estimates, prove to be significantly different than actual results, or the belief that the Company will receive an expansion permit changes adversely in a significant manner, the costs of the landfill, including the costs incurred in the pursuit of the expansion, may be subject to impairment testing, as described below, and lower profitability may be experienced due to higher amortization rates, higher capping, closure and post-closure rates, and higher expenses or asset impairments related to the removal of previously included expansion airspace. The Company periodically evaluates its landfill sites for potential impairment indicators. The Company’s judgments regarding the existence of impairment indicators are based on regulatory factors, market conditions and operational performance of its landfills. Future events could cause the Company to conclude that impairment indicators exist and that its landfill carrying costs are impaired.
Cell Processing Reserves	Cell Processing Reserves The Company records a cell processing reserve related to its E&P segment for certain locations in Louisiana and Texas for the estimated amount of expenses to be incurred upon the treatment and excavation of oilfield waste received. The cell processing reserve is the future cost to properly treat and dispose of existing waste within the cells at the various facilities. The reserve generally covers estimated costs to be incurred over a period of time up to 24 months, with the current portion representing costs estimated to be incurred in the next 12 months. The estimate is calculated based on current estimated volume in the cells, estimated percentage of waste treated, and historical average costs to treat and excavate the waste. The processing reserve represents the estimated costs to process the volumes of oilfield waste on-hand for which revenue has been recognized. At December 31, 2019 and 2018, the current portion of cell processing reserves was $3,518 and $2,835, respectively, which is included in Accrued liabilities in the Consolidated Balance Sheets. At December 31, 2019 and 2018, the long-term portion of cell processing reserves was $1,270 and $1,211, respectively, which is included in Other long-term liabilities in the Consolidated Balance Sheets.
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 on a straight-line basis over the expected term of the related agreements (ranging from 1
Goodwill and Indefinite-Lived Intangible Assets	Goodwill and Indefinite-Lived Intangible Assets The Company acquired indefinite-lived intangible assets in connection with certain of its acquisitions. The amounts assigned to indefinite-lived intangible assets consist of the value of certain perpetual rights to provide solid waste collection and transportation services in specified territories and to operate E&P waste treatment and disposal facilities. The Company measures and recognizes acquired indefinite-lived intangible assets at their estimated acquisition date fair values. Indefinite-lived intangible assets are not amortized. Goodwill represents the excess of: (a) the aggregate of the fair value of consideration transferred, the fair value of any noncontrolling interest in the acquiree (if any) and the acquisition date fair value of the Company’s previously held equity interest in the acquiree (if any), over (b) the fair value of assets acquired and liabilities assumed. Goodwill and intangible assets, deemed to have indefinite lives, are subject to annual impairment tests as described below. Goodwill and indefinite-lived intangible assets are tested for impairment on at least an annual basis in the fourth quarter of the year. In addition, the Company evaluates its reporting units for impairment if events or circumstances change between annual tests indicating a possible impairment. Examples of such events or circumstances include, but are not limited to, the following: ● ● ● ● ● The Company elected to early adopt the guidance issued by the FASB “Simplifying the Test for Goodwill Impairment” on January 1, 2017. The new guidance removes Step 2 of the goodwill impairment test, which required a hypothetical purchase price allocation. As such, the impairment analysis is only one step. In this step, the Company estimates the fair value of each of its reporting units, which consisted of testing its five geographic solid waste operating segments and its E&P segment at December 31, 2019, 2018 and 2017, using discounted cash flow analyses. The Company compares the fair value of each reporting unit with the carrying value of the net assets assigned to each reporting unit. If the fair value of a reporting unit is greater than the carrying value of the net assets, including goodwill, assigned to the reporting unit, then no impairment results. If the fair value is less than its carrying value, an impairment charge is recorded for the amount by which the carrying value exceeds its fair value, not to exceed the carrying amount of goodwill. In testing indefinite-lived intangible assets for impairment, the Company compares the estimated fair value of each indefinite-lived intangible asset to its carrying value. If the fair value of the indefinite-lived intangible asset is less than its carrying value, an impairment charge would be recorded to earnings in the Company’s Consolidated Statements of Net Income. During the Company’s annual impairment analysis of its solid waste operations, the Company determined the fair value of each of its five geographic solid waste operating segments at December 31, 2019, 2018 and 2017 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 and growth rates. The cash flows employed in the Company’s 2019 discounted cash flow analyses were based on ten-year financial forecasts, which in turn were based on the 2020 annual budget developed internally by management. These forecasts reflect operating profit margins that were consistent with 2019 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 5.7%. In assessing the reasonableness of the Company’s determined fair values of its reporting units, the Company evaluates its results against its current market capitalization. The Company did not record an impairment charge to any of its five geographic solid waste operating segments as a result of its annual goodwill Upon adopting the goodwill impairment accounting guidance in the first quarter of 2017, the Company performed an updated impairment test for its E&P segment. The impairment test involved measuring the recoverability of goodwill by comparing the E&P segment’s carrying amount, including goodwill, to the fair value of the reporting unit. The fair value was estimated using an income approach employing a discounted cash flow (“DCF”) model. The DCF model incorporated projected cash flows over a forecast period based on the remaining estimated lives of the operating locations comprising the E&P segment. This was based on a number of key assumptions, including, but not limited to, a discount rate of 11.7%, annual revenue projections based on E&P waste resulting from projected levels of oil and natural gas exploration and production activity during the forecast period, gross margins based on estimated operating expense requirements during the forecast period and estimated capital expenditures over the forecast period, all of which were classified as Level 3 in the fair value hierarchy. The impairment test showed the carrying value of the E&P segment exceeded its fair value by an amount in excess of the carrying amount of goodwill, or $77,343. Therefore, the Company recorded an impairment charge of $77,343, consisting of the carrying amount of goodwill at its E&P segment at January 1, 2017, to Impairments and other operating charges in the Consolidated Statements of Net Income during the year ended December 31, 2017. Additionally, the Company evaluated the recoverability of the E&P segment’s indefinite-lived intangible assets (other than goodwill) by comparing the estimated fair value of each indefinite-lived intangible asset to its carrying value. The Company estimated the fair value of the indefinite-lived intangible assets using an excess earnings approach. Based on the result of the recoverability test during the years ended December 31, 2019, 2018 and 2017, the Company did not record an impairment charge.
Impairments of Property and Equipment and Finite-Lived Intangible Assets	Impairments of Property and Equipment and Finite-Lived Intangible Assets Property, equipment and finite-lived intangible assets are carried on the Company’s consolidated financial statements based on their cost less accumulated depreciation or amortization. Finite-lived intangible assets consist of long-term franchise agreements, contracts, customer lists, permits and other agreements. The recoverability of these assets is tested whenever events or changes in circumstances indicate that their carrying amount may not be recoverable. Typical indicators that an asset may be impaired include, but are not limited to, the following: ● ● ● ● ● If any of these or other indicators occur, a test of recoverability is performed by comparing the carrying value of the asset or asset group to its undiscounted expected future cash flows. If the carrying value is in excess of the undiscounted expected future cash flows, impairment is measured by comparing the fair value of the asset to its carrying value. Fair value is determined by an internally developed discounted projected cash flow analysis of the asset. Cash flow projections are sometimes based on a group of assets, rather than a single asset. If cash flows cannot be separately and independently identified for a single asset, the Company will determine whether an impairment has occurred for the group of assets for which the projected cash flows can be identified. If the fair value of an asset is determined to be less than the carrying amount of the asset or asset group, an impairment in the amount of the difference is recorded in the period that the impairment indicator occurs. Several impairment indicators are beyond the Company’s control, and whether or not they will occur cannot be predicted with any certainty. Estimating future cash flows requires significant judgment and projections may vary from cash flows eventually realized. There are other considerations for impairments of landfills, as described below. During the year ended December 31, 2019, the Company recorded an $8,000 impairment charge, which is included in Impairments and other operating items in the Consolidated Statements of Net Income, for property and equipment associated with a landfill development project in its E&P segment that the Company is no longer pursuing. During the year ended December 31, 2018, the Company did not record an impairment charge for property and equipment. During the year ended December 31, 2017, the Company recorded an $11,038 impairment charge, which is included in Impairments and other operating items in the Consolidated Statements of Net Income, for property and equipment associated with a project to develop a new landfill in its Central segment that the Company is no longer pursuing. There are certain indicators listed above that require significant judgment and understanding of the waste industry when applied to landfill development or expansion projects. A regulator or court may deny or overturn a landfill development or landfill expansion permit application before the development or expansion permit is ultimately granted. Management may periodically divert waste from one landfill to another to conserve remaining permitted landfill airspace. Therefore, certain events could occur in the ordinary course of business and not necessarily be considered indicators of impairment due to the unique nature of the waste industry.
Restricted Cash and Restricted Investments	Restricted Cash and Restricted Investments Restricted cash and restricted investments consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019 ​ December 31, 2018 ​ ​ Restricted ​ Restricted ​ Restricted ​ Restricted ​ Cash Investments Cash Investments Settlement of insurance claims ​ $ 77,680 ​ $ — ​ $ 66,573 ​ $ — Landfill closure and post-closure obligations ​ ​ 12,324 ​ ​ 48,590 ​ ​ 12,325 ​ ​ 44,939 Other financial assurance requirements ​ ​ 6,479 ​ ​ 2,589 ​ ​ 5,763 ​ ​ 2,547 ​ ​ $ 96,483 ​ $ 51,179 ​ $ 84,661 ​ $ 47,486 ​ See Note 11 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, interest rate swaps and fuel hedges. As of December 31, 2019 and 2018, 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, 2019 and 2018, 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, 2019 and 2018, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Carrying Value at ​ Fair Value* at ​ ​ ​ December 31, ​ December 31, ​ December 31, ​ December 31, ​ ​ 2019 2018 2019 2018 5.25% Senior Notes due 2019 ​ $ — ​ $ 175,000 ​ $ — ​ $ 177,870 ​ 4.64% Senior Notes due 2021 ​ $ 100,000 ​ $ 100,000 ​ $ 102,654 ​ $ 101,292 ​ 2.39% Senior Notes due 2021 ​ $ 150,000 ​ $ 150,000 ​ $ 149,823 ​ $ 144,305 ​ 3.09% Senior Notes due 2022 ​ $ 125,000 ​ $ 125,000 ​ $ 126,884 ​ $ 120,682 ​ 2.75% Senior Notes due 2023 ​ $ 200,000 ​ $ 200,000 ​ $ 201,121 ​ $ 188,363 ​ 3.24% Senior Notes due 2024 ​ $ 150,000 ​ $ 150,000 ​ $ 153,804 ​ $ 142,877 ​ 3.41% Senior Notes due 2025 ​ $ 375,000 ​ $ 375,000 ​ $ 389,127 ​ $ 355,541 ​ 3.03% Senior Notes due 2026 ​ $ 400,000 ​ $ 400,000 ​ $ 406,768 ​ $ 367,143 ​ 3.49% Senior Notes due 2027 ​ $ 250,000 ​ $ 250,000 ​ $ 259,789 ​ $ 234,243 ​ 4.25% Senior Notes due 2028 ​ $ 500,000 ​ $ 500,000 ​ $ 562,050 ​ $ 506,100 ​ 3.50% Senior Notes due 2029 ​ $ 500,000 ​ $ — ​ $ 533,500 ​ $ — ​ * For details on the fair value of the Company’s interest rate swaps, fuel hedges, restricted cash and investments and contingent consideration, see Note 11.
Derivative Financial Instruments	Derivative Financial Instruments The Company recognizes all derivatives on the balance sheet at fair value. All of the Company’s derivatives have been designated as cash flow hedges; therefore, the gain or loss on the derivatives will be recognized in accumulated other comprehensive income (loss) (“AOCIL”) and reclassified into earnings in the same period during which the hedged transaction affects earnings and is presented in the same income statement line item as the earnings effect of the hedged item. The Company classifies cash inflows and outflows from derivatives within operating activities on the statement of cash flows. One of the Company’s objectives for utilizing derivative instruments is to reduce its exposure to fluctuations in cash flows due to changes in the variable interest rates of certain borrowings under the Credit Agreement (defined below). The Company’s strategy to achieve that objective involves entering into interest rate swaps. The interest rate swaps outstanding at December 31, 2019 were specifically designated to the Credit Agreement and accounted for as cash flow hedges. At December 31, 2019, the Company’s derivative instruments included 16 interest rate swap agreements as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fixed Variable ​ ​ ​ ​ Notional ​ Interest ​ Interest Rate ​ ​ ​ Expiration Date Entered ​ Amount ​ Rate Paid* ​ Received ​ Effective Date ​ Date May 2014 ​ $ 50,000 2.344 % 1-month LIBOR October 2015 October 2020 May 2014 ​ $ 25,000 2.326 % 1-month LIBOR October 2015 October 2020 May 2014 ​ $ 50,000 2.350 % 1-month LIBOR October 2015 October 2020 May 2014 ​ $ 50,000 2.350 % 1-month LIBOR October 2015 October 2020 April 2016 ​ $ 100,000 1.000 % 1-month LIBOR February 2017 February 2020 June 2016 ​ $ 75,000 0.850 % 1-month LIBOR February 2017 February 2020 June 2016 ​ $ 150,000 0.950 % 1-month LIBOR January 2018 January 2021 June 2016 ​ $ 150,000 0.950 % 1-month LIBOR January 2018 January 2021 July 2016 ​ $ 50,000 0.900 % 1-month LIBOR January 2018 January 2021 July 2016 ​ $ 50,000 0.890 % 1-month LIBOR January 2018 January 2021 August 2017 ​ $ 100,000 1.900 % 1-month LIBOR July 2019 July 2022 August 2017 ​ $ 200,000 2.200 % 1-month LIBOR October 2020 October 2025 August 2017 ​ $ 150,000 1.950 % 1-month LIBOR February 2020 February 2023 June 2018 ​ $ 200,000 ​ 2.925 % 1-month LIBOR ​ October 2020 ​ October 2025 June 2018 ​ $ 200,000 ​ 2.925 % 1-month LIBOR ​ October 2020 ​ October 2025 December 2018 ​ $ 200,000 ​ 2.850 % 1-month LIBOR ​ July 2022 ​ July 2027 * Plus applicable margin. Another of the Company’s objectives for utilizing derivative instruments is to reduce its exposure to fluctuations in cash flows due to changes in the price of diesel fuel. The Company’s strategy to achieve that objective involves periodically entering into fuel hedges that are specifically designated to certain forecasted diesel fuel purchases and accounted for as cash flow hedges. At December 31, 2019 and 2018, the Company had no The fair values of derivative instruments designated as cash flow hedges as of December 31, 2019, 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) ​ $ 2,845 Accrued liabilities (a) ​ $ (3,680) ​ ​ ​ ​ Other long-term liabilities ​ ​ (38,967) Total derivatives designated as cash flow hedges ​ ​ ​ $ 2,845 ​ ​ ​ $ (42,647) (a) Represents the estimated amount of the existing unrealized gains and losses, respectively, on interest rate swaps as of December 31, 2019 (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, 2018, 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 ​ $ 10,737 Other long-term liabilities ​ $ (9,314) ​ Other assets, net ​ 10,675 ​ ​ ​ Total derivatives designated as cash flow hedges ​ ​ ​ $ 21,412 ​ ​ ​ $ (9,314) ​ 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, 2019, 2018 and 2017: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 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), (c) ​ ​ Years Ended December 31, ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 ​ 2019 2018 2017 Interest rate swaps ​ $ (32,247) ​ $ (892) ​ $ 3,795 ​ Interest expense ​ $ (5,900) ​ $ (4,167) ​ $ 2,062 Fuel hedges ​ — ​ 1,997 ​ 959 Cost of operations ​ — ​ (4,904) ​ 2,112 Total ​ $ (32,247) ​ $ 1,105 ​ $ 4,754 ​ ​ ​ $ (5,900) ​ $ (9,071) ​ $ 4,174 (a) In accordance with the derivatives and hedging guidance, the changes in fair values of interest rate swaps and fuel hedges 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. Because changes in the actual price of diesel fuel and changes in the DOE index price did not offset exactly each reporting period, the Company assessed whether the fuel hedges were highly effective using the cumulative dollar offset approach. (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. (c) Amounts reclassified from AOCIL into earnings related to realized gains and losses on the fuel hedges are recognized when settlement payments or receipts occur related to the hedge contracts, which correspond to when the underlying fuel is consumed. See Note 14 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. On December 22, 2017, the SEC staff issued Staff Accounting Bulletin No. 118 (“SAB 118”) which provides guidance on accounting for the tax effects of the Tax Cuts and Jobs Act (“Tax Act”). The Tax Act, enacted on December 22, 2017, is comprehensive tax legislation which makes broad and complex changes to the U.S. tax code that affected 2017 and subsequent years. SAB 118 provides a measurement period that should not extend beyond one year from the Tax Act enactment date for companies to complete the accounting under Accounting Standards Codification 740 (“ASC 740”). In accordance with SAB 118, a company must reflect the income tax effects of those aspects of the Tax Act for which the accounting under ASC 740 is complete. To the extent that a company’s accounting for certain income tax effects of the Tax Act is incomplete but it is able to determine a reasonable estimate, it must record a provisional estimate in the financial statements. In connection with the Company’s analysis of the Tax Act, a discrete net income tax benefit of $269,804 was recorded in the year ended December 31, 2017. This net income tax benefit was primarily the result of the reduction to the corporate income tax rate from 35 percent to 21 percent. Additionally, the Tax Act’s one-time deemed repatriation transition tax (the “Transition Tax”) on certain unrepatriated earnings of non-U.S. subsidiaries is a tax on previously untaxed accumulated and current earnings and profits of certain of the Company’s non-U.S. subsidiaries. To determine the amount of the Transition Tax, the Company had to determine, in addition to other factors, the amount of post-1986 earnings and profits of the relevant subsidiaries, as well as the amount of non-U.S. income taxes paid on such earnings. The Company was able to make a reasonable estimate of the Transition Tax and recorded a provisional Transition Tax obligation of $1,000 for the year ended December 31, 2017. The Transition Tax, which has been determined to be complete, resulted in a total Transition Tax obligation of $746 with a corresponding adjustment of $254 to income tax expense for the year ended December 31, 2018. Further, as it relates to the Company’s policy regarding the accounting for the tax impacts of global intangible low-taxed income, it has elected to record the tax impacts as period costs. Additionally, in conjunction with the Tax Act, the Company recorded a provisional deferred income tax expense of $62,350 for the year ended December 31, 2017 associated with a portion of its U.S. earnings no longer permanently reinvested. During the year ended December 31, 2018, the Company recorded a deferred income tax expense of $6,429 associated with refinements to the prior year estimate as a measurement period adjustment pursuant to SAB 118. This resulted in total deferred income tax expense of $68,779 which has been determined to be complete.
Share-Based Compensation	Share-Based Compensation 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. T he 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, 2019, 2018 and 2017, was $42,671 ($31,926 net of taxes), $43,803 ($32,774 net of taxes) and $39,361 ($25,608 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, 2019, related to unvested RSU awards was $39,126 and this future expense will be recognized over the remaining vesting period of the RSU awards, which extends to 2023. The weighted average remaining vesting period of the RSU awards is 1.1 years. The total unrecognized compensation cost at December 31, 2019, related to unvested PSU awards was $13,221 and this future expense will be recognized over the remaining vesting period of the PSU awards, which extends to 2023. The weighted average remaining vesting period of PSU awards is 1.0 years. Other Restricted Share Units As of December 31, 2019, 2018 and 2017, the Company had a liability of $7,178, $9,799 and $10,785, respectively, representing the December 31, 2019, 2018 and 2017 fair values, respectively, of outstanding Progressive Waste restricted share units which are expected to be cash settled. For the years ended December 31, 2019 and 2018, the fair value was calculated using the number of shares granted and the closing price of the common shares in the capital of the Company. All remaining unvested Progressive Waste restricted share units vested during the year ended December 31, 2019. Other Performance-Based Restricted Share Units As of December 31, 2018 and 2017, the Company had a liability of $1,923 and $3,500, respectively, representing the December 31, 2018 and 2017 fair values, respectively, of outstanding Progressive Waste performance-based restricted share units, which were cash settled, less unrecognized compensation cost. The fair value was calculated using the volume weighted average price of the Company’s shares for the five preceding business days as of December 31, 2018 and 2017 which were $73.06, and $71.50, respectively. All remaining unvested Progressive Waste performance-based restricted share units vested during the year ended December 31, 2018. All remaining outstanding Progressive Waste performance-based restricted share units were settled during the year ended December 31, 2019. Other Share Based Options The fair value of the Progressive Waste share based options outstanding was calculated using a Black-Scholes pricing model with the following weighted average assumptions for the years ended December 31, 2019, 2018 and 2017: ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 ​ 2018 ​ 2017 Expected remaining life 1.50 years ​ 2.50 years ​ 0.92 to 2.30 years Share volatility 16.14% ​ 14.86% ​ 12.09% to 26.07% Discount rate 1.61% ​ 2.51% ​ 1.75% to 1.92% Annual dividend rate 0.82% ​ 0.86% ​ 0.79% ​ All remaining unvested Progressive Waste share based options vested during the year ended December 31, 2017. As of December 31, 2019, 2018 and 2017, the Company had a liability of $8,559, $8,812 and $10,751, respectively, representing the December 31, 2019, 2018 and 2017 fair value, respectively, of outstanding Progressive Waste share based options which are expected to be cash settled.
Per Share Information	Per Share Information Basic net income per share attributable to holders of the Company’s common shares is computed using the weighted average number of common shares outstanding and vested and unissued restricted share units deferred for issuance into the deferred compensation plan. Diluted net income per share attributable to holders of the Company’s common shares is computed using the weighted average number of common and potential common shares outstanding. Potential common shares are excluded from the computation if their effect is anti-dilutive.
Advertising Costs	Advertising Costs Advertising costs are expensed as incurred. Advertising expense for the years ended December 31, 2019, 2018 and 2017, was $5,410, $5,029 and $5,047, 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, which have a limited history, and by published industry development factors. At December 31, 2019 and 2018, the Company’s total accrual for self-insured liabilities was $127,029 and $119,506, respectively, which is included in Accrued liabilities in the Consolidated Balance Sheets. For the years ended December 31, 2019, 2018 and 2017, the Company recognized $155,748, $146,940 and $141,405, 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.
Reclassification	Reclassification As disclosed within other footnotes of the financial statements, segment information reported in the Company’s prior year have been reclassified to conform with the 2019 presentation.

Leases (Policy)

Leases (Policy)	12 Months Ended
	Dec. 31, 2019
Lessee Disclosure [Abstract]
Leases	The Company rents certain equipment and facilities under both short-term agreements and non-cancelable operating lease agreements. 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 leases are periodically reviewed for impairment losses. The Company uses the long-lived assets 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 year ended December 31, 2019. The Company monitors for events or changes in circumstances that require a reassessment of one of its leases. When a reassessment results in the remeasurement of a lease liability, a corresponding adjustment is made to the carrying amount of the corresponding ROU asset. The Company did not recognize any significant remeasurements during the year ended December 31, 2019. The Company has elected not to recognize ROU assets and lease liabilities for short-term leases that have a lease term of 12 months or less. The Company has elected to apply the short-term lease recognition and measurement exemption allowed for in the lease accounting standard. The Company recognizes the lease payments associated with its short-term leases as an expense on a straight-line basis over the lease term.

New Accounting Standards and _2

New Accounting Standards and Reclassifications (Tables)	12 Months Ended
	Dec. 31, 2019
New Accounting Standards and Reclassifications [Abstract]
Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block]	​ ​ ​ ​ As Reported ​ Adoption of Lease Guidance ​ Balance Operating lease right-of-use assets $ - ​ $ 206,501 ​ $ 206,501 Total assets $ 12,627,329 ​ $ 206,501 ​ $ 12,833,830 Current portion of operating lease liabilities $ - ​ $ 29,640 ​ $ 29,640 Total current liabilities $ 886,835 ​ $ 29,640 ​ $ 916,475 Long-term portion of operating lease liabilities $ - ​ $ 180,005 ​ $ 180,005 Deferred income taxes $ 760,033 ​ $ (1,066) ​ $ 758,967 Total liabilities $ 6,167,141 ​ $ 208,579 ​ $ 6,375,720 Retained earnings $ 2,264,510 ​ $ (2,077) ​ $ 2,262,433 Total liabilities and equity $ 12,627,329 ​ $ 206,501 ​ $ 12,833,830

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total Reported Revenues by Service Line	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 Commercial $ 1,593,217 ​ $ 1,452,831 $ 1,343,590 Residential ​ ​ 1,380,763 ​ ​ 1,189,148 ​ ​ 1,130,842 Industrial and construction roll off ​ ​ 841,173 ​ ​ 768,687 ​ ​ 707,015 Total collection ​ ​ 3,815,153 ​ ​ 3,410,666 ​ ​ 3,181,447 Landfill ​ ​ 1,132,935 ​ ​ 1,063,243 ​ ​ 988,092 Transfer ​ ​ 771,316 ​ ​ 670,129 ​ ​ 589,883 Recycling ​ ​ 64,245 ​ ​ 92,634 ​ ​ 161,730 E&P ​ ​ 271,887 ​ ​ 256,262 ​ ​ 203,473 Intermodal and other ​ ​ 121,137 ​ ​ 139,896 ​ ​ 146,749 Intercompany ​ ​ (787,994) ​ ​ (709,889) ​ ​ (640,886) Total $ 5,388,679 ​ $ 4,922,941 $ 4,630,488
Property Plant and Equipment Estimated Useful Lives	The estimated useful lives are as follows: ​ ​ ​ ​ Buildings 10 Leasehold and land improvements 3 Machinery and equipment 3 Rolling stock 3 Containers 3
Reconciliation of Final Capping, Closure and Post-Closure Liability Balance	The following is a reconciliation of the Company’s final capping, closure and post-closure liability balance from December 31, 2017 to December 31, 2019: ​ ​ ​ ​ ​ Final capping, closure and post-closure liability at December 31, 2017 $ 237,817 Liabilities incurred ​ 2,640 Accretion expense associated with landfill obligations ​ 12,777 Closure payments ​ (2,731) Assumption of closure liabilities from acquisitions ​ 4,408 Foreign currency translation adjustment ​ ​ (3,129) Final capping, closure and post-closure liability at December 31, 2018 ​ 251,782 Liabilities incurred ​ 19,846 Accretion expense associated with landfill obligations ​ 14,251 Closure payments ​ (5,059) Assumption of closure liabilities from acquisitions ​ ​ 8,707 Foreign currency translation adjustment ​ 1,947 Final capping, closure and post-closure liability at December 31, 2019 ​ $ 291,474
Restricted Cash and Restricted Investments	Restricted cash and restricted investments consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019 ​ December 31, 2018 ​ ​ Restricted ​ Restricted ​ Restricted ​ Restricted ​ Cash Investments Cash Investments Settlement of insurance claims ​ $ 77,680 ​ $ — ​ $ 66,573 ​ $ — Landfill closure and post-closure obligations ​ ​ 12,324 ​ ​ 48,590 ​ ​ 12,325 ​ ​ 44,939 Other financial assurance requirements ​ ​ 6,479 ​ ​ 2,589 ​ ​ 5,763 ​ ​ 2,547 ​ ​ $ 96,483 ​ $ 51,179 ​ $ 84,661 ​ $ 47,486
Carrying Values and Fair Values of Debt Instruments	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Carrying Value at ​ Fair Value* at ​ ​ ​ December 31, ​ December 31, ​ December 31, ​ December 31, ​ ​ 2019 2018 2019 2018 5.25% Senior Notes due 2019 ​ $ — ​ $ 175,000 ​ $ — ​ $ 177,870 ​ 4.64% Senior Notes due 2021 ​ $ 100,000 ​ $ 100,000 ​ $ 102,654 ​ $ 101,292 ​ 2.39% Senior Notes due 2021 ​ $ 150,000 ​ $ 150,000 ​ $ 149,823 ​ $ 144,305 ​ 3.09% Senior Notes due 2022 ​ $ 125,000 ​ $ 125,000 ​ $ 126,884 ​ $ 120,682 ​ 2.75% Senior Notes due 2023 ​ $ 200,000 ​ $ 200,000 ​ $ 201,121 ​ $ 188,363 ​ 3.24% Senior Notes due 2024 ​ $ 150,000 ​ $ 150,000 ​ $ 153,804 ​ $ 142,877 ​ 3.41% Senior Notes due 2025 ​ $ 375,000 ​ $ 375,000 ​ $ 389,127 ​ $ 355,541 ​ 3.03% Senior Notes due 2026 ​ $ 400,000 ​ $ 400,000 ​ $ 406,768 ​ $ 367,143 ​ 3.49% Senior Notes due 2027 ​ $ 250,000 ​ $ 250,000 ​ $ 259,789 ​ $ 234,243 ​ 4.25% Senior Notes due 2028 ​ $ 500,000 ​ $ 500,000 ​ $ 562,050 ​ $ 506,100 ​ 3.50% Senior Notes due 2029 ​ $ 500,000 ​ $ — ​ $ 533,500 ​ $ — ​ *
Fair Value of Derivative Instrument Designated as Cash Flow Hedges	The fair values of derivative instruments designated as cash flow hedges as of December 31, 2019, 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) ​ $ 2,845 Accrued liabilities (a) ​ $ (3,680) ​ ​ ​ ​ Other long-term liabilities ​ ​ (38,967) Total derivatives designated as cash flow hedges ​ ​ ​ $ 2,845 ​ ​ ​ $ (42,647) (a) Represents the estimated amount of the existing unrealized gains and losses, respectively, on interest rate swaps as of December 31, 2019 (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, 2018, 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 ​ $ 10,737 Other long-term liabilities ​ $ (9,314) ​ Other assets, net ​ 10,675 ​ ​ ​ Total derivatives designated as cash flow hedges ​ ​ ​ $ 21,412 ​ ​ ​ $ (9,314)
Impact of Cash Flow Hedges on Results of Operations, Comprehensive Income and Accumulated Other Comprehensive Loss	The following table summarizes the impact of the Company’s cash flow hedges on the results of operations, comprehensive income (loss) and AOCIL for the years ended December 31, 2019, 2018 and 2017: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 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), (c) ​ ​ Years Ended December 31, ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 ​ 2019 2018 2017 Interest rate swaps ​ $ (32,247) ​ $ (892) ​ $ 3,795 ​ Interest expense ​ $ (5,900) ​ $ (4,167) ​ $ 2,062 Fuel hedges ​ — ​ 1,997 ​ 959 Cost of operations ​ — ​ (4,904) ​ 2,112 Total ​ $ (32,247) ​ $ 1,105 ​ $ 4,754 ​ ​ ​ $ (5,900) ​ $ (9,071) ​ $ 4,174 (a) In accordance with the derivatives and hedging guidance, the changes in fair values of interest rate swaps and fuel hedges 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. Because changes in the actual price of diesel fuel and changes in the DOE index price did not offset exactly each reporting period, the Company assessed whether the fuel hedges were highly effective using the cumulative dollar offset approach. (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. (c) Amounts reclassified from AOCIL into earnings related to realized gains and losses on the fuel hedges are recognized when settlement payments or receipts occur related to the hedge contracts, which correspond to when the underlying fuel is consumed.
Interest Rate Swap [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Company's Derivative Instruments	At December 31, 2019, the Company’s derivative instruments included 16 interest rate swap agreements as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fixed Variable ​ ​ ​ ​ Notional ​ Interest ​ Interest Rate ​ ​ ​ Expiration Date Entered ​ Amount ​ Rate Paid* ​ Received ​ Effective Date ​ Date May 2014 ​ $ 50,000 2.344 % 1-month LIBOR October 2015 October 2020 May 2014 ​ $ 25,000 2.326 % 1-month LIBOR October 2015 October 2020 May 2014 ​ $ 50,000 2.350 % 1-month LIBOR October 2015 October 2020 May 2014 ​ $ 50,000 2.350 % 1-month LIBOR October 2015 October 2020 April 2016 ​ $ 100,000 1.000 % 1-month LIBOR February 2017 February 2020 June 2016 ​ $ 75,000 0.850 % 1-month LIBOR February 2017 February 2020 June 2016 ​ $ 150,000 0.950 % 1-month LIBOR January 2018 January 2021 June 2016 ​ $ 150,000 0.950 % 1-month LIBOR January 2018 January 2021 July 2016 ​ $ 50,000 0.900 % 1-month LIBOR January 2018 January 2021 July 2016 ​ $ 50,000 0.890 % 1-month LIBOR January 2018 January 2021 August 2017 ​ $ 100,000 1.900 % 1-month LIBOR July 2019 July 2022 August 2017 ​ $ 200,000 2.200 % 1-month LIBOR October 2020 October 2025 August 2017 ​ $ 150,000 1.950 % 1-month LIBOR February 2020 February 2023 June 2018 ​ $ 200,000 ​ 2.925 % 1-month LIBOR ​ October 2020 ​ October 2025 June 2018 ​ $ 200,000 ​ 2.925 % 1-month LIBOR ​ October 2020 ​ October 2025 December 2018 ​ $ 200,000 ​ 2.850 % 1-month LIBOR ​ July 2022 ​ July 2027 * Plus applicable margin.
Employee Stock Option [Member] | Progressive Waste Plans [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair Value Assumptions	The fair value of the Progressive Waste share based options outstanding was calculated using a Black-Scholes pricing model with the following weighted average assumptions for the years ended December 31, 2019, 2018 and 2017: ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 ​ 2018 ​ 2017 Expected remaining life 1.50 years ​ 2.50 years ​ 0.92 to 2.30 years Share volatility 16.14% ​ 14.86% ​ 12.09% to 26.07% Discount rate 1.61% ​ 2.51% ​ 1.75% to 1.92% Annual dividend rate 0.82% ​ 0.86% ​ 0.79%

Acquisitions (Tables)

Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2019
Acquisitions [Abstract]
Summary of Consideration Transferred to Acquire Businesses and Amounts of Identifiable Assets Acquired, Liabilities Assumed and Noncontrolling Interests	The following table summarizes the consideration transferred to acquire these businesses and the amounts of identifiable assets acquired and liabilities assumed at the acquisition dates for the acquisitions consummated in the years ended December 31, 2019, 2018 and 2017: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2019 2018 2017 ​ ​ Acquisitions ​ Acquisitions ​ Acquisitions Fair value of consideration transferred: ​ ​ ​ Cash ​ $ 736,610 ​ $ 830,091 ​ $ 410,695 Debt assumed ​ 95,809 ​ 210,461 ​ 56,958 Notes issued to sellers ​ — ​ — ​ 13,460 Fair value of operations exchanged ​ — ​ — ​ 81,097 Change in open working capital settlements at year end ​ ​ 5,272 ​ ​ (8,507) ​ ​ — ​ ​ 837,691 ​ 1,032,045 ​ 562,210 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired: ​ ​ ​ Accounts receivable ​ 25,220 ​ 23,682 ​ 19,228 Prepaid expenses and other current assets ​ 4,970 ​ 4,614 ​ 10,722 Property and equipment ​ 294,037 ​ 437,914 ​ 169,433 Long-term franchise agreements and contracts ​ 78,312 ​ 10,888 ​ 54,674 Indefinite-lived intangibles ​ — ​ — ​ 5,830 Customer lists ​ 52,422 ​ 133,387 ​ 33,529 Permits and other intangibles ​ ​ 48,141 ​ ​ 23,935 ​ ​ 27,261 Other assets ​ 7 ​ 19 ​ 3,052 Accounts payable and accrued liabilities ​ (19,209) ​ (25,005) ​ (12,020) Deferred revenue ​ (17,245) ​ (16,238) ​ (6,883) Contingent consideration ​ (14,038) ​ (11,669) ​ (2,885) Other long-term liabilities ​ (8,707) ​ (15,532) ​ (1,080) Deferred income taxes ​ (13,287) ​ (391) ​ (50,283) Total identifiable net assets ​ 430,623 ​ 565,604 ​ 250,578 Goodwill ​ $ 407,068 ​ $ 466,441 ​ $ 311,632

Intangible Assets, Net (Tables)

Intangible Assets, Net (Tables)	12 Months Ended
	Dec. 31, 2019
Intangible Assets, Net [Abstract]
Intangible Assets Exclusive of Goodwill	Intangible assets, exclusive of goodwill, consisted of the following at December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ ​ Accumulated Net ​ ​ Carrying ​ Accumulated ​ Impairment ​ Carrying ​ ​ Amount ​ Amortization ​ Loss ​ Amount Finite-lived intangible assets: ​ ​ ​ ​ Long-term franchise agreements and contracts ​ $ 550,340 ​ $ (192,462) ​ $ — ​ $ 357,878 Customer lists ​ 587,562 ​ (308,427) ​ — ​ 279,135 Permits and other ​ 367,127 ​ (63,299) ​ — ​ 303,828 ​ ​ 1,505,029 ​ (564,188) ​ — ​ 940,841 Indefinite-lived intangible assets: ​ ​ ​ ​ Solid waste collection and transportation permits ​ 158,591 ​ — ​ — ​ 158,591 Material recycling facility permits ​ 42,283 ​ — ​ — ​ 42,283 E&P facility permits ​ 59,855 ​ — ​ (38,507) ​ 21,348 ​ ​ 260,729 ​ — ​ (38,507) ​ 222,222 Intangible assets, exclusive of goodwill ​ $ 1,765,758 ​ $ (564,188) ​ $ (38,507) ​ $ 1,163,063 Intangible assets, exclusive of goodwill, consisted of the following at December 31, 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ ​ Accumulated Net ​ ​ Carrying ​ Accumulated ​ Impairment ​ Carrying ​ ​ Amount ​ Amortization ​ Loss ​ Amount Finite-lived intangible assets: ​ ​ ​ ​ Long-term franchise agreements and contracts ​ $ 476,833 ​ $ (157,986) ​ $ — ​ $ 318,847 Customer lists ​ 530,614 ​ (232,461) ​ — ​ 298,153 Permits and other ​ 338,601 ​ (49,195) ​ — ​ 289,406 ​ ​ 1,346,048 ​ (439,642) ​ — ​ 906,406 Indefinite-lived intangible assets: ​ ​ ​ ​ ​ ​ Solid waste collection and transportation permits ​ 158,591 ​ — ​ — ​ 158,591 Material recycling facility permits ​ 42,283 ​ — ​ — ​ 42,283 E&P facility permits ​ 59,855 ​ — ​ (38,507) ​ 21,348 ​ ​ 260,729 ​ — ​ (38,507) ​ 222,222 Intangible assets, exclusive of goodwill ​ $ 1,606,777 ​ $ (439,642) ​ $ (38,507) ​ $ 1,128,628
Estimated Future Amortization Expense of Amortizable Intangible Assets	Estimated future amortization expense for the next five years relating to finite-lived intangible assets is as follows: ​ ​ ​ ​ ​ For the year ending December 31, 2020 $ 126,000 For the year ending December 31, 2021 ​ $ 109,234 For the year ending December 31, 2022 ​ $ 94,173 For the year ending December 31, 2023 ​ $ 79,710 For the year ending December 31, 2024 ​ $ 68,350

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	12 Months Ended
	Dec. 31, 2019
Property and Equipment, Net [Abstract]
Property and Equipment	Property and equipment, net consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2019 2018 Landfill site costs ​ $ 4,334,562 ​ $ 3,981,870 Rolling stock ​ 2,011,283 ​ 1,736,673 Land, buildings and improvements ​ 1,079,420 ​ 963,903 Containers ​ 764,607 ​ 682,990 Machinery and equipment ​ 749,557 ​ 660,961 Construction in progress ​ 23,739 ​ 25,692 ​ ​ 8,963,168 ​ 8,052,089 Less accumulated depreciation and depletion ​ (3,446,821) ​ (2,883,093) ​ ​ $ 5,516,347 ​ $ 5,168,996

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2019
Lessee Disclosure [Abstract]
Summary of lease cost for operating leases	Lease cost for operating leases for the year ended December 31, 2019 was as follows: ​ ​ ​ ​ ​ ​ ​ Year Ended ​ December 31, 2019 Operating lease cost ​ $ 38,710 ​ Supplemental cash flow information and non-cash activity related to the Company’s operating leases are as follows: ​ ​ ​ ​ ​ ​ Year Ended ​ ​ December 31, 2019 Operating cash flow information: ​ ​ ​ Cash paid for amounts included in the measurement of lease liabilities ​ $ 38,226 Non-cash activity: ​ ​ ​ Right-of-use assets obtained in exchange for lease liabilities ​ $ 10,746 ​ Weighted-average remaining lease term and discount rate for the Company’s operating leases are as follows: ​ ​ ​ ​ ​ ​ ​ Year Ended ​ December 31, 2019 Weighted average remaining lease term ​ 8.7 years Weighted average discount rate ​ 3.99 %
Summary of future minimum lease payments	As of December 31, 2019, future minimum lease payments, as calculated under the new lease guidance and reconciled to the operating lease liability, are as follows: ​ ​ ​ ​ ​ 2020 $ 36,718 2021 ​ 33,432 2022 ​ 32,087 2023 ​ 28,750 2024 ​ 20,382 Thereafter ​ 75,716 Minimum lease payments ​ 227,085 Less: imputed interest ​ (37,123) Present value of minimum lease payments ​ ​ 189,962 Less: current portion of operating lease liabilities ​ ​ (29,929) Long-term portion of operating lease liabilities ​ $ 160,033
Summary of future minimum lease payments under non-cancelable operating leases	As of December 31, 2018, minimum lease payments under non-cancelable operating leases by period were expected to be as follows: ​ ​ ​ ​ ​ 2019 $ 37,902 2020 ​ ​ 35,204 2021 ​ ​ 32,259 2022 ​ ​ 30,974 2023 ​ ​ 27,882 Thereafter ​ ​ 94,205 ​ ​ $ 258,426
Summary of rent expense for both short-term agreements and non-cancelable operating lease agreements	A summary of rent expense for both short-term agreements and non-cancelable operating lease agreements for the years ended December 31, 2018 and 2017 was as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ 2018 2017 Rent expense ​ $ 42,646 ​ $ 43,383

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	12 Months Ended
	Dec. 31, 2019
Accrued Liabilities [Abstract]
Accrued Liabilities	Accrued liabilities consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2019 2018 Insurance claims ​ $ 127,029 ​ $ 119,506 Payroll and payroll-related ​ 71,593 ​ 87,136 Interest payable ​ 17,286 ​ 16,971 Final capping, closure and post-closure liability - current portion ​ ​ 7,707 ​ ​ 26,126 Unrealized cash flow hedge losses ​ 3,680 ​ — Cell processing reserve - current portion ​ 3,518 ​ 2,835 Environmental remediation reserve - current portion ​ 2,314 ​ 3,592 Share-based compensation plan liability – current portion ​ 930 ​ 6,209 Other ​ 47,251 ​ 53,295 ​ ​ $ 281,308 ​ $ 315,670

Long-Term Debt (Tables)

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2019
Long-Term Debt [Abstract]
Long-Term Debt	The following table presents the Company’s long-term debt as of December 31, 2019 and 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ ​ 2019 2018 Revolver under Credit Agreement, bearing interest ranging from 2.90% to 3.18% (a) ​ $ 916,247 ​ $ 481,610 ​ Term loan under Credit Agreement, bearing interest at 2.90% (a) ​ 700,000 ​ 1,237,500 ​ 5.25% Senior Notes due 2019 ​ — ​ 175,000 ​ 4.64% Senior Notes due 2021 ​ 100,000 ​ 100,000 ​ 2.39% Senior Notes due 2021 ​ 150,000 ​ 150,000 ​ 3.09% Senior Notes due 2022 ​ 125,000 ​ 125,000 ​ 2.75% Senior Notes due 2023 ​ 200,000 ​ 200,000 ​ 3.24% Senior Notes due 2024 ​ 150,000 ​ 150,000 ​ 3.41% Senior Notes due 2025 ​ 375,000 ​ 375,000 ​ 3.03% Senior Notes due 2026 ​ 400,000 ​ 400,000 ​ 3.49% Senior Notes due 2027 ​ 250,000 ​ 250,000 ​ 4.25% Senior Notes due 2028 ​ ​ 500,000 ​ ​ 500,000 ​ 3.50% Senior Notes due 2029 ​ ​ 500,000 ​ ​ — ​ Tax-exempt bonds ​ — ​ 15,930 ​ Notes payable to sellers and other third parties, bearing interest ranging from 2.75% to 10.90%, principal and interest payments due periodically with due dates ranging from 2020 to 2036 (a) ​ 9,638 ​ 14,653 ​ ​ ​ 4,375,885 ​ 4,174,693 ​ Less – current portion ​ (465) ​ (1,786) ​ Less – debt issuance costs ​ (21,638) ​ (19,442) ​ ​ ​ $ 4,353,782 ​ $ 4,153,465 ​
Details of the Company's Credit Agreement	Details of the Credit Agreement are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ December 31, ​ ​ 2019 2018 Revolver under Credit Agreement ​ ​ ​ Available ​ $ 538,642 ​ $ 955,779 ​ ​ Letters of credit outstanding ​ $ 107,611 ​ $ 125,111 ​ ​ Total amount drawn, as follows: ​ $ 916,247 ​ $ 481,610 ​ ​ Amount drawn - U.S. LIBOR rate loan ​ $ 897,000 ​ $ 357,000 ​ ​ Interest rate applicable - U.S. LIBOR rate loan ​ ​ 2.90 % ​ 3.62 % ​ Interest rate margin - U.S. LIBOR rate loan ​ ​ 1.10 % ​ 1.10 % ​ Amount drawn – Canadian bankers’ acceptance ​ $ 19,247 ​ $ 124,610 ​ ​ Interest rate applicable – Canadian bankers’ acceptance ​ 3.18 % 3.40 % ​ Interest rate acceptance fee – Canadian bankers’ acceptance ​ 1.10 % 1.10 % ​ Commitment – rate applicable ​ 0.12 % 0.12 % ​ Term loan under Credit Agreement ​ ​ ​ ​ ​ Amount drawn – U.S. based LIBOR loan ​ $ 700,000 ​ $ 1,237,500 ​ ​ Interest rate applicable – U.S. based LIBOR loan ​ 2.90 % 3.62 % ​ Interest rate margin – U.S. based LIBOR loan ​ 1.10 % ​ 1.10 % ​
Aggregate Contractual Future Principal Payments by Calendar Year on Long-Term Debt	As of December 31, 2019, aggregate contractual future principal payments by calendar year on long-term debt are due as follows: ​ ​ ​ ​ ​ 2020 $ 465 2021 ​ 254,298 2022 ​ 125,430 2023 ​ 1,816,703 2024 ​ 150,483 Thereafter ​ 2,028,506 ​ ​ $ 4,375,885

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2019
Fair Value of Financial Instruments [Abstract]
Assets and Liabilities Measured At Fair Value on Recurring Basis	The Company’s assets and liabilities measured at fair value on a recurring basis at December 31, 2019 and 2018, were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurement at December 31, 2019 Using ​ ​ ​ Quoted Prices in Significant ​ ​ ​ ​ ​ ​ ​ Active Markets ​ Other ​ Significant ​ ​ ​ ​ ​ for Identical ​ Observable ​ Unobservable ​ ​ ​ ​ ​ Assets ​ Inputs ​ Inputs ​ ​ Total ​ (Level 1) ​ (Level 2) ​ (Level 3) Interest rate swap derivative instruments – net liability position ​ $ (39,802) ​ $ — ​ $ (39,802) ​ $ — Restricted cash and investments ​ $ 147,318 ​ $ — ​ $ 147,318 ​ $ — Contingent consideration ​ $ (68,984) ​ $ — ​ $ — ​ $ (68,984) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurement at December 31, 2018 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 ​ $ 12,098 ​ $ — ​ $ 12,098 ​ $ — Restricted cash and investments ​ $ 131,422 ​ $ — ​ $ 131,422 ​ $ — Contingent consideration ​ $ (54,615) ​ $ — ​ $ — ​ $ (54,615)
Changes in the Fair Value for Level 3 Liabilities Related to Contingent Consideration	The following table summarizes the changes in the fair value for Level 3 liabilities related to contingent consideration for the years ended December 31, 2019 and 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ ​ 2019 2018 Beginning balance ​ $ 54,615 ​ $ 47,285 ​ Contingent consideration recorded at acquisition date ​ 14,038 ​ 11,669 ​ Payment of contingent consideration recorded at acquisition date ​ (3,200) ​ (6,127) ​ Payment of contingent consideration recorded in earnings ​ — ​ (11) ​ Adjustments to contingent consideration ​ ​ 1,498 ​ 349 ​ Interest accretion expense ​ 1,852 ​ 1,756 ​ Foreign currency translation adjustment ​ 181 ​ (306) ​ Ending balance ​ $ 68,984 ​ $ 54,615 ​

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2019
Commitments and Contingencies [Abstract]
Future Minimum Purchase Commitments	As of December 31, 2019, future minimum purchase commitments, by calendar year, are as follows: ​ ​ ​ ​ ​ 2020 $ 76,799 2021 ​ 52,574 ​ ​ $ 129,373

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common Stock Shares Reserved for Issuance	​ ​ ​ ​ For outstanding RSUs, PSUs and warrants 1,991,919 For future grants under the 2016 Incentive Award Plan 5,431,669 ​ 7,423,588
Restricted Stock Units Activity	A summary of the Company’s RSU activity is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 Weighted average grant-date fair value of restricted share units granted ​ $ 81.24 ​ $ 69.22 ​ $ 57.09 Total fair value of restricted share units vested ​ $ 21,136 ​ $ 18,795 ​ $ 16,715
Summary of Warrant Activity	A summary of warrant activity during the year ended December 31, 2019, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ Warrants ​ Exercise Price Outstanding at December 31, 2018 268,211 ​ $ 63.49 Granted 151,008 ​ $ 91.43 Forfeited (15,728) ​ $ 35.05 Exercised (25,067) ​ $ 33.38 Outstanding at December 31, 2019 378,424 ​ $ 77.81
Summarized Information about Warrants Outstanding	The following table summarizes information about warrants outstanding as of December 31, 2019 and 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value of ​ ​ ​ ​ ​ ​ Warrants ​ ​ ​ Warrants ​ Outstanding at December 31, Grant Date ​ Issued ​ Exercise Price ​ Issued ​ 2019 ​ 2018 Throughout 2014 75,604 ​ $30.41 to $32.71 276 — 15,416 Throughout 2015 136,768 ​ $28.30 to $36.32 1,333 21,515 45,978 Throughout 2016 15,666 ​ $42.22 to $51.55 189 7,158 7,440 Throughout 2017 35,382 ​ $53.65 to $69.96 595 35,382 35,382 Throughout 2018 163,995 ​ $70.91 to $80.90 2,591 163,361 163,995 Throughout 2019 ​ 151,008 ​ $74.25 to $95.61 ​ 2,634 ​ 151,008 ​ — ​ ​ ​ ​ ​ 378,424 268,211
Restricted Stock Units (RSUs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Summary of Activity Related to Restricted Stock Units	A summary of activity related to RSUs during the year ended December 31, 2019, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ Grant Date Fair ​ Unvested Shares ​ Value Per Share Outstanding at December 31, 2018 987,563 ​ $ 56.43 Granted 345,127 ​ $ 81.24 Forfeited (54,987) ​ $ 66.73 Vested and issued (416,691) ​ $ 50.72 Outstanding at December 31, 2019 861,012 ​ $ 68.47
Performance Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance-Based Restricted Share Units Activity	A summary of the Company’s PSU activity is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 Weighted average grant-date fair value of PSUs granted ​ $ 80.85 ​ $ 68.77 ​ $ 56.55 Total fair value of PSUs vested ​ $ 7,683 ​ $ 5,886 ​ $ 4,098
Summary of Performance-Based Restricted Stock Units Activity and Related Information	A summary of activity related to PSUs during the year ended December 31, 2019, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ Grant Date Fair ​ Unvested Shares ​ Value Per Share Outstanding at December 31, 2018 532,086 ​ $ 53.43 Granted 152,656 ​ $ 80.85 Vested and issued (180,258) ​ $ 42.62 Outstanding at December 31, 2019 504,484 ​ $ 65.59
Deferred Share Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted Stock Units Activity	A summary of the Company’s deferred share units (“DSUs”) activity is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 ​ 2018 2017 Weighted average grant-date fair value of DSUs granted ​ $ 83.80 ​ $ 70.47 ​ $ 57.65 Total fair value of DSUs awarded ​ $ 319 ​ $ 285 ​ $ 272
Summary of Activity Related to Restricted Stock Units	A summary of activity related to DSUs during the year ended December 31, 2019, is presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ Grant Date Fair ​ Vested Shares ​ Value Per Share Outstanding at December 31, 2018 17,176 ​ $ 48.24 Granted 3,804 ​ $ 83.80 Cash settled (2,010) ​ $ 68.83 Outstanding at December 31, 2019 18,970 ​ $ 53.19
Progressive Waste Solutions Ltd. [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Summary of Stock Option Activity and Related Information	​ ​ ​ ​ Outstanding at December 31, 2018 165,156 Cash settled (38,995) Outstanding at December 31, 2019 126,161
Progressive Waste Solutions Ltd. [Member] | Restricted Stock Units (RSUs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Summary of Activity Related to Restricted Stock Units	​ ​ ​ ​ Outstanding at December 31, 2018 122,259 Cash settled (46,023) Forfeited (2,352) Outstanding at December 31, 2019 73,884
Summary of Vesting Activity Related to RSUs	A summary of vesting activity related to Progressive Waste RSUs during the year ended December 31, 2019, is presented below: ​ ​ ​ ​ Vested at December 31, 2018 120,153 Vested over remaining service period 2,106 Cash settled (46,023) Forfeited (2,352) Vested at December 31, 2019 73,884
Progressive Waste Solutions Ltd. [Member] | Performance Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Summary of Performance-Based Restricted Stock Units Activity and Related Information	​ ​ ​ ​ Outstanding at December 31, 2018 22,791 Cash settled, net of notional dividend (22,791) Outstanding at December 31, 2019 —

Other Comprehensive Income (L_2

Other Comprehensive Income (Loss) (Tables)	12 Months Ended
	Dec. 31, 2019
Other Comprehensive Income (Loss) [Abstract]
Components of Other Comprehensive Income (Loss)	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2019 ​ Gross Tax Effect Net of Tax Interest rate swap amounts reclassified into interest expense ​ $ (8,027) ​ $ 2,127 ​ $ (5,900) Changes in fair value of interest rate swaps ​ (43,873) ​ 11,626 ​ (32,247) Foreign currency translation adjustment ​ 101,970 ​ — ​ 101,970 ​ ​ $ 50,070 ​ $ 13,753 ​ $ 63,823 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2018 ​ Gross Tax Effect Net of Tax Interest rate swap amounts reclassified into interest expense ​ $ (5,669) ​ $ 1,502 ​ $ (4,167) Fuel hedge amounts reclassified into cost of operations ​ (6,531) ​ 1,627 ​ (4,904) Changes in fair value of interest rate swaps ​ (1,213) ​ 321 ​ (892) Changes in fair value of fuel hedge ​ 2,651 ​ (654) ​ 1,997 Foreign currency translation adjustment ​ (175,233) ​ — ​ (175,233) ​ ​ $ (185,995) ​ $ 2,796 ​ $ (183,199) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2017 ​ Gross Tax Effect Net of Tax Interest rate swap amounts reclassified into interest expense ​ $ 2,805 ​ $ (743) ​ $ 2,062 Fuel hedge amounts reclassified into cost of operations ​ 2,818 ​ (706) ​ 2,112 Changes in fair value of interest rate swaps ​ 7,835 ​ (4,040) ​ 3,795 Changes in fair value of fuel hedges ​ 1,326 ​ (367) ​ 959 Foreign currency translation adjustment ​ ​ 142,486 ​ ​ — ​ ​ 142,486 ​ ​ $ 157,270 ​ $ (5,856) ​ $ 151,414
Amounts Included in Accumulated Other Comprehensive Loss	A roll forward of the amounts included in AOCIL, net of taxes, is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Foreign Accumulated ​ ​ ​ ​ ​ ​ ​ ​ Currency ​ Other ​ ​ ​ ​ ​ Interest ​ Translation ​ Comprehensive ​ ​ Fuel Hedges ​ Rate Swaps ​ Adjustment ​ Income (Loss) Balance at December 31, 2017 ​ $ 2,907 ​ $ 13,951 ​ $ 91,555 ​ $ 108,413 Amounts reclassified into earnings ​ (4,904) ​ (4,167) ​ — ​ (9,071) Changes in fair value ​ 1,997 ​ (892) ​ — ​ 1,105 Foreign currency translation adjustment ​ — ​ — ​ (175,233) ​ (175,233) Balance at December 31, 2018 ​ ​ — ​ ​ 8,892 ​ ​ (83,678) ​ ​ (74,786) Amounts reclassified into earnings ​ ​ — ​ ​ (5,900) ​ ​ — ​ ​ (5,900) Changes in fair value ​ ​ — ​ ​ (32,247) ​ ​ — ​ ​ (32,247) Foreign currency translation adjustment ​ ​ — ​ ​ — ​ ​ 101,970 ​ ​ 101,970 Balance at December 31, 2019 ​ $ — ​ $ (29,255) ​ $ 18,292 ​ $ (10,963)

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2019
Income Taxes [Abstract]
Income (Loss) Before Provision (Benefit) for Income Taxes	Income before provision for income taxes consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 U.S. ​ $ 477,203 ​ $ 491,506 ​ $ 301,962 Non – U.S. ​ 228,688 ​ 215,634 ​ 206,548 Income before income taxes ​ $ 705,891 ​ $ 707,140 ​ $ 508,510
Provision (Benefit) for Income Taxes	The provision (benefit) for income taxes for the years ended December 31, 2019, 2018 and 2017, consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 Current: ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. Federal ​ $ 45,475 ​ $ 37,419 ​ $ 45,089 State ​ 27,528 ​ 27,057 ​ 19,848 Non – U.S. ​ 11,570 ​ 17,651 ​ 18,537 ​ ​ 84,573 ​ 82,127 ​ 83,474 Deferred: ​ ​ ​ U.S. Federal ​ 58,291 ​ 85,926 ​ (203,131) State ​ 6,331 ​ 1,991 ​ 7,534 Non – U.S. ​ (9,985) ​ (10,058) ​ 43,213 ​ ​ 54,637 ​ 77,859 ​ (152,384) Provision (benefit) for income taxes ​ $ 139,210 ​ $ 159,986 ​ $ (68,910)
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, as of December 31, 2019 and 2018 are presented below. ​ ​ ​ ​ ​ ​ ​ ​ ​ 2019 2018 Deferred income tax assets: ​ ​ Accrued expenses ​ $ 23,536 ​ $ 26,128 Compensation ​ 17,532 ​ 19,830 Contingent liabilities ​ 15,228 ​ 14,043 Finance costs ​ — ​ 2,329 Tax credits and loss carryforwards ​ 18,693 ​ 20,438 Interest rate and fuel hedges ​ 10,548 ​ — Gross deferred income tax assets ​ 85,537 ​ 82,768 Less: Valuation allowance ​ — ​ — Total deferred income tax assets ​ 85,537 ​ 82,768 ​ ​ ​ ​ ​ ​ ​ Deferred income tax liabilities: ​ ​ ​ ​ ​ ​ Goodwill and other intangibles ​ (311,404) ​ (283,671) Property and equipment ​ (497,768) ​ (461,071) Landfill closure/post-closure ​ (12,159) ​ (8,892) Prepaid expenses ​ (8,542) ​ (11,581) Interest rate and fuel hedges ​ — ​ (3,206) Investment in subsidiaries ​ (69,597) ​ (69,383) Other ​ ​ (4,689) ​ ​ (4,997) Total deferred income tax liabilities ​ (904,159) ​ (842,801) Net deferred income tax liability ​ $ (818,622) ​ $ (760,033)
Differences between Income Tax Provision in Statements of Net Income and Income Tax Provision Computed at Federal Statutory Rate	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 U.S. federal statutory rate ​ 21.0 % 21.0 % 35.0 % State taxes, net of federal benefit 4.4 4.4 4.1 ​ Deferred income tax liability adjustments 0.6 (0.2) 0.5 ​ Effect of international operations (6.3) (3.9) (14.6) ​ Enactment of the Tax Act — — (53.1) ​ Deferred tax on undistributed earnings — 0.9 12.3 ​ Goodwill impairment — — 2.1 ​ Other — 0.4 0.1 ​ ​ 19.7 % 22.6 % (13.6) %

Segment Reporting (Tables)

Segment Reporting (Tables)	12 Months Ended
	Dec. 31, 2019
Segment Reporting [Abstract]
Summary of Financial Information Concerning Company's Reportable Segments	Summarized financial information concerning the Company’s reportable segments for the years ended December 31, 2019, 2018 and 2017, is shown in the following tables: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ Intercompany ​ Reported ​ Segment ​ Depreciation and ​ Capital ​ ​ ​ December 31, 2019 ​ Revenue ​ Revenue (b) ​ Revenue ​ EBITDA (c) ​ Amortization ​ Expenditures ​ Total Assets (e) Eastern ​ $ 1,524,648 ​ $ (255,684) ​ $ 1,268,964 ​ $ 330,578 ​ $ 204,221 ​ $ 154,218 ​ $ 3,099,283 Southern ​ ​ 1,355,753 ​ ​ (162,831) ​ ​ 1,192,922 ​ ​ 305,999 ​ ​ 160,038 ​ ​ 141,157 ​ ​ 2,990,247 Western ​ 1,234,669 ​ (135,820) ​ 1,098,849 ​ 338,563 ​ 102,067 ​ 147,893 ​ 1,718,015 Central ​ 958,139 ​ (119,555) ​ 838,584 ​ 292,111 ​ 106,391 ​ 116,831 ​ 1,885,468 Canada ​ 835,603 ​ (102,321) ​ 733,282 ​ 256,405 ​ 113,944 ​ 61,119 ​ 2,490,291 E&P ​ 267,861 ​ (11,783) ​ 256,078 ​ 135,426 ​ 48,929 ​ 36,970 ​ 962,202 Corporate (a), (d) ​ — ​ — ​ — ​ (15,438) ​ 8,328 ​ 7,901 ​ 592,189 ​ ​ $ 6,176,673 ​ $ (787,994) ​ $ 5,388,679 ​ $ 1,643,644 ​ $ 743,918 ​ $ 666,089 ​ $ 13,737,695 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ Intercompany ​ Reported ​ Segment ​ Depreciation and ​ Capital ​ ​ ​ December 31, 2018 ​ Revenue ​ Revenue (b) ​ Revenue ​ EBITDA (c) ​ Amortization ​ Expenditures ​ Total Assets (e) Eastern ​ $ 1,296,823 ​ $ (224,833) ​ $ 1,071,990 ​ $ 295,016 ​ $ 166,715 ​ $ 136,214 ​ $ 2,673,316 Southern ​ ​ 1,273,033 ​ ​ (150,485) ​ ​ 1,122,548 ​ ​ 276,791 ​ ​ 153,923 ​ ​ 97,442 ​ ​ 2,892,994 Western ​ 1,170,382 ​ (126,454) ​ 1,043,928 ​ 318,401 ​ 95,400 ​ 125,112 ​ 1,596,129 Central ​ 815,520 ​ (103,966) ​ 711,554 ​ 259,794 ​ 89,001 ​ 91,646 ​ 1,506,326 Canada ​ 823,989 ​ (96,776) ​ 727,213 ​ 261,233 ​ 124,155 ​ 66,319 ​ 2,412,971 E&P ​ 253,083 ​ (7,375) ​ 245,708 ​ 129,825 ​ 44,175 ​ 25,937 ​ 969,808 Corporate (a), (d) ​ — ​ — ​ — ​ (8,211) ​ 7,118 ​ 3,475 ​ 575,785 ​ ​ $ 5,632,830 ​ $ (709,889) ​ $ 4,922,941 ​ $ 1,532,849 ​ $ 680,487 ​ $ 546,145 ​ $ 12,627,329 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ ​ ​ ​ Intercompany ​ Reported ​ Segment ​ Depreciation and ​ Capital ​ ​ ​ December 31, 2017 ​ Revenue ​ Revenue (b) ​ Revenue ​ EBITDA (c) ​ Amortization ​ Expenditures ​ Total Assets (e) Eastern ​ $ 1,120,221 ​ $ (178,394) ​ $ 941,827 ​ $ 269,106 ​ $ 135,737 ​ $ 100,025 ​ $ 2,009,328 Southern ​ 1,262,147 ​ (146,283) ​ 1,115,864 ​ 258,560 ​ 151,417 ​ 117,441 ​ 2,718,296 Western ​ 1,127,146 ​ (119,916) ​ 1,007,230 ​ 323,648 ​ 95,724 ​ 100,000 ​ 1,573,955 Central ​ 734,042 ​ (88,488) ​ 645,554 ​ 241,972 ​ 79,460 ​ 79,544 ​ 1,312,317 Canada ​ 828,755 ​ (99,978) ​ 728,777 ​ 264,693 ​ 121,174 ​ 62,690 ​ 2,677,557 E&P ​ 199,063 ​ (7,827) ​ 191,236 ​ 90,597 ​ 42,500 ​ 12,274 ​ 981,980 Corporate (a), (d) ​ — ​ — ​ — ​ (32,501) ​ 6,472 ​ 7,313 ​ 741,248 ​ ​ $ 5,271,374 ​ $ (640,886) ​ $ 4,630,488 ​ $ 1,416,075 ​ $ 632,484 ​ $ 479,287 ​ $ 12,014,681 (a) Corporate functions include accounting, legal, tax, treasury, information technology, risk management, human resources, training, direct acquisition expenses, other administrative functions and share-based compensation expenses associated with Progressive Waste share-based grants existing at June 1, 2016. Amounts reflected are net of allocations to the six operating segments. For the years ended December 31, 2018 and 2017, amounts also include Progressive Waste integration-related expenses. (b) Intercompany revenues reflect each segment’s total intercompany sales, including intercompany sales within a segment and between segments. Transactions within and between segments are generally made on a basis intended to reflect the market value of the service. (c) For those items included in the determination of segment EBITDA, the accounting policies of the segments are the same as those described in Note 3. (d) Corporate assets include cash, debt issuance costs, equity investments, operating lease right-of-use assets and corporate facility leasehold improvements and equipment. (e) Goodwill is included within total assets for each of the Company’s six operating segments.
Changes in Goodwill by Reportable Segment	The following table shows changes in goodwill during the years ended December 31, 2018 and 2019, by reportable segment: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Eastern Southern Western Central Canada E&P Total Balance as of December 31, 2017 ​ $ 804,133 ​ $ 1,436,320 ​ $ 397,508 ​ $ 468,275 ​ $ 1,575,538 ​ $ — ​ $ 4,681,774 Goodwill transferred ​ ​ (16,869) ​ ​ — ​ ​ — ​ ​ 16,869 ​ ​ — ​ ​ — ​ ​ — Goodwill acquired ​ 339,222 ​ 71,109 ​ 666 ​ 55,291 ​ 153 ​ — ​ 466,441 Goodwill adjustment for assets sold ​ — ​ 10,181 ​ — ​ — ​ — ​ — ​ 10,181 Impact of changes in foreign currency ​ — ​ — ​ — ​ — ​ (126,711) ​ — ​ (126,711) Balance as of December 31, 2018 ​ ​ 1,126,486 ​ ​ 1,517,610 ​ ​ 398,174 ​ ​ 540,435 ​ ​ 1,448,980 ​ ​ — ​ ​ 5,031,685 Goodwill acquired ​ 204,694 ​ 11,460 ​ ​ 1,863 ​ 189,035 ​ ​ 16 ​ ​ — ​ 407,068 Goodwill divested ​ — ​ (845) ​ — ​ — ​ — ​ — ​ (845) Impact of changes in foreign currency ​ — ​ — ​ — ​ — ​ 72,943 ​ — ​ 72,943 Balance as of December 31, 2019 ​ $ 1,331,180 ​ $ 1,528,225 ​ $ 400,037 ​ $ 729,470 ​ $ 1,521,939 ​ $ — ​ $ 5,510,851
Property and Equipment, Net Relating to Operations	Property and equipment, net relating to operations in the United States and Canada are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ 2019 2018 United States ​ $ 4,862,557 ​ $ 4,516,966 Canada ​ 653,790 ​ 652,030 Total ​ $ 5,516,347 ​ $ 5,168,996
Reconciliation of Primary Measure of Segment Profitability to Income before Income Tax Provision	A reconciliation of the Company’s primary measure of segment profitability (segment EBITDA) to Income before income tax provision in the Consolidated Statements of Net Income is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years ended December 31, ​ 2019 2018 2017 Eastern segment EBITDA ​ $ 330,578 ​ $ 295,016 ​ $ 269,106 Southern segment EBITDA ​ ​ 305,999 ​ ​ 276,791 ​ ​ 258,560 Western segment EBITDA ​ 338,563 ​ 318,401 ​ 323,648 Central segment EBITDA ​ 292,111 ​ 259,794 ​ 241,972 Canada segment EBITDA ​ 256,405 ​ 261,233 ​ 264,693 E&P segment EBITDA ​ 135,426 ​ 129,825 ​ 90,597 Subtotal reportable segments ​ 1,659,082 ​ 1,541,060 ​ 1,448,576 Unallocated corporate overhead ​ (15,438) ​ (8,211) ​ (32,501) Depreciation ​ (618,396) ​ (572,708) ​ (530,187) Amortization of intangibles ​ (125,522) ​ (107,779) ​ (102,297) Impairments and other operating items ​ (61,948) ​ (20,118) ​ (156,493) Interest expense ​ (147,368) ​ (132,104) ​ (125,297) Interest income ​ 9,777 ​ 7,170 ​ 5,173 Other income (expense), net ​ 5,704 ​ (170) ​ 1,536 Income before income tax provision ​ $ 705,891 ​ $ 707,140 ​ $ 508,510

Net Income Per Share Informat_2

Net Income Per Share Information (Tables)	12 Months Ended
	Dec. 31, 2019
Net Income Per Share Information [Abstract]
Basic and Diluted Net Income (Loss) Per Common Share	The following table sets forth the calculation of the numerator and denominator used in the computation of basic and diluted net income per common share attributable to the Company’s shareholders for the years ended December 31, 2019, 2018 and 2017: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Years Ended December 31, ​ 2019 2018 2017 Numerator: ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income attributable to Waste Connections for basic and diluted earnings per share ​ $ 566,841 ​ $ 546,871 ​ $ 576,817 Denominator: ​ ​ ​ ​ ​ Basic shares outstanding ​ 263,792,693 ​ 263,650,155 ​ 263,682,608 Dilutive effect of equity-based awards ​ 733,868 ​ 745,463 ​ 619,803 Diluted shares outstanding ​ 264,526,561 ​ 264,395,618 ​ 264,302,411

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2019
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 ​ Bargaining Plan Name Number 2019 2018 (a),(b) 2019 2018 2017 Agreement Local 731, I.B. of T., Private Scavengers, Garage Attendants, and Textile Maintenance Pension Trust Fund 36-6513567 - 001 Green for the plan year ended 9/30/2019 Green for the plan year ended 9/30/2017 Not applicable ​ $ 4,570 ​ $ 4,600 ​ $ 4,342 9/30/2023 Western Conference of Teamsters Pension Trust 91-6145047 - 001 Green Green Not applicable ​ ​ 4,550 ​ ​ 4,399 ​ ​ 4,191 12/31/2019 to 7/31/2022 Suburban Teamsters of Northern Illinois Pension Fund 36-6155778 - 001 Green for the plan year beginning 1/1/2019 Yellow Not applicable ​ 1,844 ​ 1,569 ​ 877 1/31/2024 Teamster Local 301 Pension Fund 36-6492992 - 001 Green Green Not applicable ​ 624 ​ 581 ​ 489 9/30/2023 Automobile Mechanics’ Local No. 701 Union and Industry Pension Fund 36-6042061 - 001 Yellow Yellow Implemented ​ 492 ​ 484 ​ 837 12/31/2022 Midwest Operating Engineers Pension Plan 36-6140097 - 001 Green for the plan year beginning 4/1/2019 Yellow for the plan year ended 3/31/2017 Not applicable ​ 339 ​ 289 ​ 207 10/31/2020 Locals 302 & 612 of the IOUE - Employers Construction Industry Retirement Plan 91-6028571 - 001 Green Green Not applicable ​ 290 ​ 284 ​ 275 11/16/2022 Local 813 Pension Trust Fund 13-1975659 - 001 Critical Critical Implemented ​ 281 ​ 165 ​ 158 11/30/2019 IAM National Pension Fund ​ 51-6031295 - 002 ​ Green ​ Green ​ Not applicable ​ ​ 256 ​ ​ 240 ​ ​ 215 ​ 12/31/2022 International Union of Operating Engineers Pension Trust 85512-1 Green as of 4/30/2017 Green as of 4/30/2017 Not applicable ​ 238 ​ 224 ​ 219 3/31/2020 to 3/31/2021 Multi-Sector Pension Plan 1085653 Green as of 1/1/2019 Green Not applicable ​ 202 ​ 191 ​ 228 12/31/2018 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 13,686 ​ $ 13,026 ​ $ 12,038 ​ ​ ​ (a) Unless otherwise noted in the table above, the most recent Pension Protection Act zone status available in 2019 and 2018 is for the plans’ years ended December 31, 2018 and 2017, 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, 2019 and 2018.

Selected Quarterly Financial _2

Selected Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2019
Selected Quarterly Financial Data [Abstract]
Consolidated Quarterly Results of Operations	The following table summarizes the Company’s unaudited consolidated quarterly results of operations for 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ First Quarter Second Quarter Third Quarter Fourth Quarter Revenues ​ $ 1,244,637 ​ $ 1,369,639 ​ $ 1,412,444 ​ $ 1,361,960 Operating income ​ $ 184,860 ​ $ 222,134 ​ $ 236,600 ​ $ 194,184 Net income ​ $ 125,577 ​ $ 148,839 ​ $ 159,074 ​ $ 133,191 Net income attributable to Waste Connections ​ $ 125,622 ​ $ 148,848 ​ $ 159,109 ​ $ 133,262 Basic income per common share attributable to Waste Connections’ common shareholders ​ $ 0.48 ​ $ 0.56 ​ $ 0.60 ​ $ 0.51 Diluted income per common share attributable to Waste Connections’ common shareholders ​ $ 0.48 ​ $ 0.56 ​ $ 0.60 ​ $ 0.50 The following table summarizes the Company’s unaudited consolidated quarterly results of operations for 2018: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ First Quarter Second Quarter Third Quarter Fourth Quarter Revenues ​ $ 1,140,131 ​ $ 1,239,968 ​ $ 1,281,110 ​ $ 1,261,732 Operating income ​ $ 188,707 ​ $ 210,688 ​ $ 232,869 ​ $ 199,980 Net income ​ $ 125,032 ​ $ 138,814 ​ $ 150,766 ​ $ 132,543 Net income attributable to Waste Connections ​ $ 124,869 ​ $ 138,682 ​ $ 150,843 ​ $ 132,478 Basic income per common share attributable to Waste Connections’ common shareholders ​ $ 0.47 ​ $ 0.53 ​ $ 0.57 ​ $ 0.50 Diluted income per common share attributable to Waste Connections’ common shareholders ​ $ 0.47 ​ $ 0.52 ​ $ 0.57 ​ $ 0.50

New Accounting Standards and _3

New Accounting Standards and Reclassifications (New Accounting Standards) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018	Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating Lease, Right-of-Use Asset	$ 183,220
Assets	13,737,695		$ 12,627,329	$ 12,014,681
Operating Lease, Liability, Current	29,929
Liabilities Current	1,007,228		886,835
Operating Lease, Liability, Noncurrent	160,033
Deferred Tax Liabilities Noncurrent	818,622		760,033
Liabilities	6,799,341		6,167,141
Retained Earnings Accumulated Deficit	2,654,207		2,264,510
Liabilities And Stockholders Equity	$ 13,737,695		12,627,329
Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating Lease, Right-of-Use Asset		$ 206,501
Assets		12,833,830
Operating Lease, Liability, Current		29,640
Liabilities Current		916,475
Operating Lease, Liability, Noncurrent		180,005
Deferred Tax Liabilities Noncurrent		758,967
Liabilities		6,375,720
Retained Earnings Accumulated Deficit		2,262,433
Liabilities And Stockholders Equity		$ 12,833,830
Accounting Standards Update 2016-02 [Member] | Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating Lease, Right-of-Use Asset			206,501
Assets			206,501
Operating Lease, Liability, Current			29,640
Liabilities Current			29,640
Operating Lease, Liability, Noncurrent			180,005
Deferred Tax Liabilities Noncurrent			(1,066)
Liabilities			208,579
Retained Earnings Accumulated Deficit			(2,077)
Liabilities And Stockholders Equity			$ 206,501

Summary of Significant Accoun_4

Summary of Significant Accounting Policies (Narrative) (Detail) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended		12 Months Ended
	Dec. 31, 2018USD ($)agreement$ / shares	Sep. 30, 2019USD ($)	Sep. 30, 2018USD ($)	Dec. 31, 2019USD ($)agreementsegment	Dec. 31, 2018USD ($)agreement$ / shares	Dec. 31, 2017USD ($)$ / shares	Mar. 31, 2017	Jan. 01, 2017USD ($)
Organization And Summary Of Significant Accounting Policies [Line Items]
Deferred sales incentives	$ 16,900			$ 16,900	$ 16,900
Sales incentives amortization expense				$ 19,673	17,313
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				176 years
Average remaining landfill life based on permitted capacity, projected annual disposal volumes and probable expansion capacity				29 years
Restricted cash	84,661			$ 96,483	84,661
Restricted investments	47,486			51,179	47,486
Cell processing reserve, current	2,835			3,518	2,835
Cell processing reserve, noncurrent	1,211			$ 1,270	1,211
Perpetual revenue growth rate				4.50%
Weighted average cost of capital				5.70%
Goodwill	$ 5,031,685			$ 5,510,851	5,031,685	$ 4,681,774
Number of geographic operating segments | segment				5
Forecasts period used for discounted cash flow analyses				10 years
Indefinite-lived intangible asset write-down				$ 0	0	0
Impairment charges					0
Number of interest rate swap agreements | agreement				16
Liabilities incurred				$ 19,846	$ 2,640
Number of fuel hedge agreements | agreement	0			0	0
Contractual life of warrants				5 years
Share-based compensation expense				$ 42,671	$ 43,803	39,361
Share-based compensation expense, net of taxes				31,926	32,774	25,608
Advertising costs				5,410	5,029	5,047
Accrual for self insured liabilities	$ 119,506			127,029	119,506
Self-insurance expense				$ 155,748	146,940	141,405
Net deferred income tax expense (benefit) from enactment of tax reform					$ 5,572	$ (269,804)
Statutory income tax rate	21.00%			21.00%	21.00%	35.00%
Transition Tax obligation	$ 746				$ 746
Adjustment to income tax expense from Transition Tax					254
Provisional deferred income tax expense						$ 62,350
Provisional Transition Tax obligation						1,000
Deferred income tax expense					68,779
Cumulative effect adjustment from adoption of new accounting pronouncement	13,243			$ (2,077)	13,243
Deferred income taxes	760,033			818,622	760,033
Operating lease liability				189,962
Operating lease, right-of-use asset				$ 183,220
Adjustment [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Deferred income tax expense					6,429
Officer [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Share-based compensation expense			$ 5,005
Minimum [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Standard customer service agreement period				1 year
Estimated life of relevant customer relationship				1 year
Expected term of related agreements				1 year
Maximum [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Standard customer service agreement period				3 years
Estimated life of relevant customer relationship				5 years
Expected term of related agreements				56 years
Restricted Stock Units (RSUs) [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Unrecognized compensation cost related to unvested awards				$ 39,126
Restricted stock unit awards, vesting final year				2023
Weighted average remaining vesting period				1 year 1 month 6 days
Restricted Stock Units (RSUs) [Member] | Progressive Waste Plans [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Share-based compensation liability	9,799			$ 7,178	9,799	10,785
Performance Shares [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Unrecognized compensation cost related to unvested awards				$ 13,221
Restricted stock unit awards, vesting final year				2023
Weighted average remaining vesting period				1 year
Performance Shares [Member] | Progressive Waste Plans [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Share-based compensation liability	$ 1,923				$ 1,923	$ 3,500
Weighted average share price | $ / shares	$ 73.06				$ 73.06	$ 71.50
Employee Stock Option [Member] | Progressive Waste Plans [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Contractual life of warrants				1 year 6 months	2 years 6 months
Share-based compensation liability	$ 8,812			$ 8,559	$ 8,812	$ 10,751
Employee Stock Option [Member] | Minimum [Member] | Progressive Waste Plans [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Contractual life of warrants						11 months 1 day
Employee Stock Option [Member] | Maximum [Member] | Progressive Waste Plans [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Contractual life of warrants						2 years 3 months 18 days
Western [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Goodwill	398,174			400,037	398,174	$ 397,508
Central [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Goodwill	540,435			729,470	540,435	468,275
Impairment charges						11,038
Eastern [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Goodwill	1,126,486			1,331,180	1,126,486	804,133
Southern [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Goodwill	1,517,610			1,528,225	1,517,610	1,436,320
Canada [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Goodwill	$ 1,448,980			1,521,939	1,448,980	1,575,538
Exploration and Production [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Goodwill write-down						77,343
Goodwill				0				$ 77,343
Impairment charges		$ 8,000		8,000
Geographic Operating Segments [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Goodwill write-down				0	0	0
Indefinite-lived intangible asset write-down				$ 0	$ 0	$ 0
Landfill [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Inflation rate for purposes of computing layers for final capping, closure and post-closure obligations				2.50%	2.50%
Landfill [Member] | Minimum [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Standard customer service agreement period				1 year
Landfill [Member] | Maximum [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Standard customer service agreement period				10 years
Measurement Input, Discount Rate [Member] | Exploration and Production [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Goodwill impairment measurement input							11.70%
Measurement Input, Discount Rate [Member] | Landfill [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Discount rate	4.75%			4.75%	4.75%

Summary of Significant Accoun_5

Summary of Significant Accounting Policies (Total Reported Revenues by Service Line) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenue from External Customer [Line Items]
Revenues	$ 5,388,679	$ 4,922,941	$ 4,630,488
Operating Segments [Member] | Solid Waste Collection
Revenue from External Customer [Line Items]
Revenues	3,815,153	3,410,666	3,181,447
Operating Segments [Member] | Solid Waste Collection | Commercial [Member]
Revenue from External Customer [Line Items]
Revenues	1,593,217	1,452,831	1,343,590
Operating Segments [Member] | Solid Waste Collection | Residential [Member]
Revenue from External Customer [Line Items]
Revenues	1,380,763	1,189,148	1,130,842
Operating Segments [Member] | Solid Waste Collection | Industrial and Construction Roll Off [Member]
Revenue from External Customer [Line Items]
Revenues	841,173	768,687	707,015
Operating Segments [Member] | Landfill [Member]
Revenue from External Customer [Line Items]
Revenues	1,132,935	1,063,243	988,092
Operating Segments [Member] | Transfer [Member]
Revenue from External Customer [Line Items]
Revenues	771,316	670,129	589,883
Operating Segments [Member] | Recycling
Revenue from External Customer [Line Items]
Revenues	64,245	92,634	161,730
Operating Segments [Member] | E&P Waste Treatment, Recovery and Disposal [Member]
Revenue from External Customer [Line Items]
Revenues	271,887	256,262	203,473
Operating Segments [Member] | Intermodal and Other
Revenue from External Customer [Line Items]
Revenues	121,137	139,896	146,749
Intercompany Revenues [Member]
Revenue from External Customer [Line Items]
Revenues	$ (787,994)	$ (709,889)	$ (640,886)

Summary of Significant Accoun_6

Summary of Significant Accounting Policies (Property Plant and Equipment Estimated Useful Lives) (Detail)	12 Months Ended
	Dec. 31, 2019
Buildings [Member] | Minimum [Member]
Property Plant and Equipment Estimated Useful Lives [Line Items]
Property, Plant and Equipment	10 years
Buildings [Member] | Maximum [Member]
Property Plant and Equipment Estimated Useful Lives [Line Items]
Property, Plant and Equipment	20 years
Leasehold and Land Improvements [Member] | Minimum [Member]
Property Plant and Equipment Estimated Useful Lives [Line Items]
Property, Plant and Equipment	3 years
Leasehold and Land Improvements [Member] | Maximum [Member]
Property Plant and Equipment Estimated Useful Lives [Line Items]
Property, Plant and Equipment	10 years
Machinery and Equipment [Member] | Minimum [Member]
Property Plant and Equipment Estimated Useful Lives [Line Items]
Property, Plant and Equipment	3 years
Machinery and Equipment [Member] | Maximum [Member]
Property Plant and Equipment Estimated Useful Lives [Line Items]
Property, Plant and Equipment	12 years
Rolling Stock [Member] | Minimum [Member]
Property Plant and Equipment Estimated Useful Lives [Line Items]
Property, Plant and Equipment	3 years
Rolling Stock [Member] | Maximum [Member]
Property Plant and Equipment Estimated Useful Lives [Line Items]
Property, Plant and Equipment	10 years
Containers [Member] | Minimum [Member]
Property Plant and Equipment Estimated Useful Lives [Line Items]
Property, Plant and Equipment	3 years
Containers [Member] | Maximum [Member]
Property Plant and Equipment Estimated Useful Lives [Line Items]
Property, Plant and Equipment	12 years

Summary of Significant Accoun_7

Summary of Significant Accounting Policies (Reconciliation of Final Capping, Closure and Post-Closure Liability Balance) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Business [Abstract]
Final capping, closure and post-closure liability at the beginning of the period	$ 251,782	$ 237,817
Liabilities incurred	19,846	2,640
Accretion expense associated with landfill obligations	14,251	12,777
Closure payments	(5,059)	(2,731)
Assumption of closure liabilities from acquisitions	8,707	4,408
Foreign currency translation adjustment	1,947	(3,129)
Final capping, closure and post-closure liability at the end of the period	$ 291,474	$ 251,782

Summary of Significant Accoun_8

Summary of Significant Accounting Policies (Restricted Cash and Investments) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Restricted cash	$ 96,483	$ 84,661
Restricted investments	51,179	47,486
Restricted Settlement of Insurance Claims [Member]
Restricted cash	77,680	66,573
Restricted Landfill Closure and Post-Closure Obligations [Member]
Restricted cash	12,324	12,325
Restricted investments	48,590	44,939
Restricted Other Financial Assurance Requirements [Member]
Restricted cash	6,479	5,763
Restricted investments	$ 2,589	$ 2,547

Summary of Significant Accoun_9

Summary of Significant Accounting Policies (Carrying Values and Fair Values of Debt Instruments) (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Nov. 30, 2019	Apr. 16, 2019	Apr. 20, 2017
Debt Instrument [Line Items]
Carrying value of senior notes	$ 4,375,885,000	$ 4,174,693,000
Senior Notes due 2019 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Carrying value of senior notes		175,000,000
Fair value of senior notes		$ 177,870,000
Interest rate of senior notes	5.25%	5.25%	5.25%
Senior note year due	2019	2019
Senior Notes due 2021 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Carrying value of senior notes	$ 100,000,000	$ 100,000,000
Fair value of senior notes	$ 102,654,000	$ 101,292,000
Interest rate of senior notes	4.64%	4.64%
Senior note year due	2021	2021
Senior Notes due 2021 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Carrying value of senior notes	$ 150,000,000	$ 150,000,000
Fair value of senior notes	$ 149,823,000	$ 144,305,000
Interest rate of senior notes	2.39%	2.39%
Senior note year due	2021	2021
Senior Notes due 2022 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Carrying value of senior notes	$ 125,000,000	$ 125,000,000
Fair value of senior notes	$ 126,884,000	$ 120,682,000
Interest rate of senior notes	3.09%	3.09%
Senior note year due	2022	2022
Senior Notes due 2023 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Carrying value of senior notes	$ 200,000,000	$ 200,000,000
Fair value of senior notes	$ 201,121,000	$ 188,363,000
Interest rate of senior notes	2.75%	2.75%
Senior note year due	2023	2023
Senior Notes due 2024 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Carrying value of senior notes	$ 150,000,000	$ 150,000,000			$ 150,000,000
Fair value of senior notes	$ 153,804,000	$ 142,877,000
Interest rate of senior notes	3.24%	3.24%
Senior note year due	2024	2024
Senior Notes due 2025 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Carrying value of senior notes	$ 375,000,000	$ 375,000,000
Fair value of senior notes	$ 389,127,000	$ 355,541,000
Interest rate of senior notes	3.41%	3.41%
Senior note year due	2025	2025
Senior Notes due 2026 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Carrying value of senior notes	$ 400,000,000	$ 400,000,000
Fair value of senior notes	$ 406,768,000	$ 367,143,000
Interest rate of senior notes	3.03%	3.03%
Senior note year due	2026	2026
Senior Notes due 2027 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Carrying value of senior notes	$ 250,000,000	$ 250,000,000			$ 250,000,000
Fair value of senior notes	$ 259,789,000	$ 234,243,000
Interest rate of senior notes	3.49%	3.49%			3.49%
Senior note year due	2027	2027
Senior Notes due 2028 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Carrying value of senior notes	$ 500,000,000	$ 500,000,000
Fair value of senior notes	$ 562,050,000	$ 506,100,000
Interest rate of senior notes	4.25%
Senior note year due	2028
Senior Notes due 2029 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Carrying value of senior notes	$ 500,000,000
Fair value of senior notes	$ 533,500,000
Interest rate of senior notes	3.50%			3.50%
Senior note year due	2029

Summary of Significant Accou_10

Summary of Significant Accounting Policies (Company's Derivative Instruments of Interest Rate Swaps) (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)
Interest Rate Swap One [Member]
Derivative [Line Items]
Date entered	2014-05
Notional amount	$ 50,000
Fixed interest rate paid	2.344%
Description of variable rate basis	1-month LIBOR
Effective date	2015-10
Expiration date	2020-10
Interest Rate Swap Two [Member]
Derivative [Line Items]
Date entered	2014-05
Notional amount	$ 25,000
Fixed interest rate paid	2.326%
Description of variable rate basis	1-month LIBOR
Effective date	2015-10
Expiration date	2020-10
Interest Rate Swap Three [Member]
Derivative [Line Items]
Date entered	2014-05
Notional amount	$ 50,000
Fixed interest rate paid	2.35%
Description of variable rate basis	1-month LIBOR
Effective date	2015-10
Expiration date	2020-10
Interest Rate Swap Four [Member]
Derivative [Line Items]
Date entered	2014-05
Notional amount	$ 50,000
Fixed interest rate paid	2.35%
Description of variable rate basis	1-month LIBOR
Effective date	2015-10
Expiration date	2020-10
Interest Rate Swap Five [Member]
Derivative [Line Items]
Date entered	2016-04
Notional amount	$ 100,000
Fixed interest rate paid	1.00%
Description of variable rate basis	1-month LIBOR
Effective date	2017-02
Expiration date	2020-02
Interest Rate Swap Six [Member]
Derivative [Line Items]
Date entered	2016-06
Notional amount	$ 75,000
Fixed interest rate paid	0.85%
Description of variable rate basis	1-month LIBOR
Effective date	2017-02
Expiration date	2020-02
Interest Rate Swap Seven [Member]
Derivative [Line Items]
Date entered	2016-06
Notional amount	$ 150,000
Fixed interest rate paid	0.95%
Description of variable rate basis	1-month LIBOR
Effective date	2018-01
Expiration date	2021-01
Interest Rate Swap Eight [Member]
Derivative [Line Items]
Date entered	2016-06
Notional amount	$ 150,000
Fixed interest rate paid	0.95%
Description of variable rate basis	1-month LIBOR
Effective date	2018-01
Expiration date	2021-01
Interest Rate Swap Nine [Member]
Derivative [Line Items]
Date entered	2016-07
Notional amount	$ 50,000
Fixed interest rate paid	0.90%
Description of variable rate basis	1-month LIBOR
Effective date	2018-01
Expiration date	2021-01
Interest Rate Swap Ten [Member]
Derivative [Line Items]
Date entered	2016-07
Notional amount	$ 50,000
Fixed interest rate paid	0.89%
Description of variable rate basis	1-month LIBOR
Effective date	2018-01
Expiration date	2021-01
Interest Rate Swap Eleven [Member]
Derivative [Line Items]
Date entered	2017-08
Notional amount	$ 100,000
Fixed interest rate paid	1.90%
Description of variable rate basis	1-month LIBOR
Effective date	2019-07
Expiration date	2022-07
Interest Rate Swap Twelve [Member]
Derivative [Line Items]
Date entered	2017-08
Notional amount	$ 200,000
Fixed interest rate paid	2.20%
Description of variable rate basis	1-month LIBOR
Effective date	2020-10
Expiration date	2025-10
Interest Rate Swap Thirteen [Member]
Derivative [Line Items]
Date entered	2017-08
Notional amount	$ 150,000
Fixed interest rate paid	1.95%
Description of variable rate basis	1-month LIBOR
Effective date	2020-02
Expiration date	2023-02
Interest Rate Swap Fourteen [Member]
Derivative [Line Items]
Date entered	2018-06
Notional amount	$ 200,000
Fixed interest rate paid	2.925%
Description of variable rate basis	1-month LIBOR
Effective date	2020-10
Expiration date	2025-10
Interest Rate Swap Fifteen [Member]
Derivative [Line Items]
Date entered	2018-06
Notional amount	$ 200,000
Fixed interest rate paid	2.925%
Description of variable rate basis	1-month LIBOR
Effective date	2020-10
Expiration date	2025-10
Interest Rate Swap Sixteen [Member]
Derivative [Line Items]
Date entered	2018-12
Notional amount	$ 200,000
Fixed interest rate paid	2.85%
Description of variable rate basis	1-month LIBOR
Effective date	2022-07
Expiration date	2027-07

Summary of Significant Accou_11

Summary of Significant Accounting Policies (Fair Values of Derivative Instruments Designated as Cash Flow Hedges) (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Derivatives designated as cash flow hedges, asset derivatives	$ 2,845	$ 21,412
Derivatives designated as cash flow hedges, liability derivatives	(42,647)	(9,314)
Interest Rate Swap [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivatives designated as cash flow hedges, liability derivatives	(3,680)
Interest Rate Swap [Member] | Other Long-term Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivatives designated as cash flow hedges, liability derivatives	(38,967)	(9,314)
Interest Rate Swap [Member] | Prepaid Expenses and Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivatives designated as cash flow hedges, asset derivatives	$ 2,845	10,737
Interest Rate Swap [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivatives designated as cash flow hedges, asset derivatives		$ 10,675

Summary of Significant Accou_12

Summary of Significant Accounting Policies (Impact of Cash Flow Hedges on Results of Operations, Comprehensive Income and Accumulated Other Comprehensive Loss) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized as AOCIL on Derivatives, Net of Tax	$ (32,247)	$ 1,105	$ 4,754
Amount of Gain or (Loss) Recognized from AOCIL into Earnings, Net of Tax	(5,900)	(9,071)	4,174
Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized as AOCIL on Derivatives, Net of Tax	(32,247)	(892)	3,795
Amount of Gain or (Loss) Recognized from AOCIL into Earnings, Net of Tax	(5,900)	(4,167)	2,062
Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized as AOCIL on Derivatives, Net of Tax	(32,247)	1,105	4,754
Amount of Gain or (Loss) Recognized from AOCIL into Earnings, Net of Tax	(5,900)	(9,071)	4,174
Cash Flow Hedging | Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized as AOCIL on Derivatives, Net of Tax	(32,247)	(892)	3,795
Cash Flow Hedging | Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized from AOCIL into Earnings, Net of Tax	$ (5,900)	(4,167)	2,062
Cash Flow Hedging | Cost of Operations [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized from AOCIL into Earnings, Net of Tax		(4,904)	2,112
Fuel [Member] | Commodity Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized as AOCIL on Derivatives, Net of Tax		1,997	959
Amount of Gain or (Loss) Recognized from AOCIL into Earnings, Net of Tax		(4,904)	2,112
Fuel [Member] | Cash Flow Hedging | Commodity Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized as AOCIL on Derivatives, Net of Tax		$ 1,997	$ 959

Summary of Significant Accou_13

Summary of Significant Accounting Policies (Fair Value Assumptions) (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected remaining life	5 years
Progressive Waste Plans [Member] | Employee Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected remaining life	1 year 6 months	2 years 6 months
Share volatility	16.14%	14.86%
Share volatility, minimum			12.09%
Share volatility, maximum			26.07%
Discount rate	1.61%	2.51%
Annual dividend rate	0.82%	0.86%	0.79%
Minimum [Member] | Progressive Waste Plans [Member] | Employee Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected remaining life			11 months 1 day
Discount rate			1.75%
Maximum [Member] | Progressive Waste Plans [Member] | Employee Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected remaining life			2 years 3 months 18 days
Discount rate			1.92%

Acquisitions (Narrative) (Detai

Acquisitions (Narrative) (Detail)	3 Months Ended								12 Months Ended
	Dec. 31, 2019USD ($)	Sep. 30, 2019USD ($)	Jun. 30, 2019USD ($)	Mar. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2019USD ($)agreement	Dec. 31, 2019USD ($)	Dec. 31, 2019USD ($)entity	Dec. 31, 2018USD ($)entity	Dec. 31, 2017USD ($)entity
Business Acquisition [Line Items]
Cash consideration, net of cash acquired											$ 736,610,000		$ 830,091,000	$ 410,695,000
Contingent considerations	$ 14,038,000								$ 14,038,000	$ 14,038,000	14,038,000	$ 14,038,000
Acquisition related costs											12,335,000		$ 8,607,000	5,700,000
Number of individual businesses acquired that are not specifically described | entity													20
Payment of contingent consideration recorded at acquisition date											3,200,000		$ 6,127,000	$ 17,158,000
Number of individual businesses acquired in period | entity												21		14
Revenues	1,361,960,000	$ 1,412,444,000	$ 1,369,639,000	$ 1,244,637,000	$ 1,261,732,000	$ 1,281,110,000	$ 1,239,968,000	$ 1,140,131,000			5,388,679,000		4,922,941,000	$ 4,630,488,000
Income before income tax provision											705,891,000		707,140,000	508,510,000
Impairments and other operating items											61,948,000		20,118,000	156,493,000
Goodwill expected to be deductible for tax purposes	266,310,000				455,283,000				266,310,000	266,310,000	266,310,000	$ 266,310,000	455,283,000	62,887,000
Trade receivables acquired in business combination gross contractual amount	27,297,000				27,795,000				27,297,000	27,297,000	27,297,000	27,297,000	27,795,000	20,746,000
Trade receivables acquired In business combination expected to be uncollectible amount	$ 2,077,000				4,113,000				$ 2,077,000	$ 2,077,000	$ 2,077,000	$ 2,077,000	$ 4,113,000	1,518,000
Fair value of acquired working capital is provisional										9		9
Measurement Input, Discount Rate [Member]
Business Acquisition [Line Items]
Contingent consideration measurement input	2.3								2.3	2.3	2.3	2.3
Maximum [Member]
Business Acquisition [Line Items]
Contingent consideration payable period									4 years
Minimum [Member]
Business Acquisition [Line Items]
Contingent consideration payable period									1 year
One Acquisition [Member]
Business Acquisition [Line Items]
Contingent consideration payable period													3 years
Contingent considerations					$ 11,593,000								$ 11,593,000
One Acquisition [Member] | Measurement Input, Discount Rate [Member]
Business Acquisition [Line Items]
Contingent consideration measurement input					0.027								0.027
One Acquisition [Member] | Maximum [Member]
Business Acquisition [Line Items]
Contingent considerations					$ 12,582,000								$ 12,582,000
Debt [Member]
Business Acquisition [Line Items]
Liabilities incurred											$ 95,809,000		$ 210,461,000	$ 56,958,000

Acquisitions (Summary of Consid

Acquisitions (Summary of Consideration Transferred to Acquire Businesses and Amounts of Identifiable Assets Acquired, Liabilities Assumed and Noncontrolling Interests) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Fair value of consideration transferred:
Cash	$ 736,610	$ 830,091	$ 410,695
Notes issued to sellers			13,460
Fair value of operations exchanged			81,097
Working capital settlements receivable	5,272	(8,507)
Consideration transferred	837,691	1,032,045	562,210
Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired:
Accounts receivable	25,220	23,682	19,228
Prepaid expenses and other current assets	4,970	4,614	10,722
Property and equipment	294,037	437,914	169,433
Indefinite-lived intangibles			5,830
Other noncurrent assets	7	19	3,052
Deferred revenue	(17,245)	(16,238)	(6,883)
Other long-term liabilities	(8,707)	(15,532)	(1,080)
Deferred income taxes	(13,287)	(391)	(50,283)
Total identifiable net assets	430,623	565,604	250,578
Goodwill	407,068	466,441	311,632
Accounts Payable and Accrued Liabilities [Member]
Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired:
Accounts payable and accrued liabilities	(19,209)	(25,005)	(12,020)
Debt [Member]
Fair value of consideration transferred:
Liabilities incurred	95,809	210,461	56,958
Contingent Consideration [Member]
Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired:
Other long-term liabilities	(14,038)	(11,669)	(2,885)
Long-Term Franchise Agreements and Contracts [Member]
Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired:
Intangibles	78,312	10,888	54,674
Customer Lists [Member]
Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired:
Intangibles	52,422	133,387	33,529
Permits and Other [Member]
Recognized amounts of identifiable assets acquired and liabilities assumed associated with businesses acquired:
Intangibles	$ 48,141	$ 23,935	$ 27,261

Intangible Assets, Net (Narrati

Intangible Assets, Net (Narrative) (Detail)	12 Months Ended
	Dec. 31, 2019
Long-term Franchise Agreements and Contracts
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average amortization period of acquired intangible assets	16 years 1 month 6 days
Customer Lists [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average amortization period of acquired intangible assets	10 years 6 months
Permits and Other [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average amortization period of acquired intangible assets	38 years 9 months 18 days

Intangible Assets, Net (Intangi

Intangible Assets, Net (Intangible Assets Exclusive of Goodwill) (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying amount	$ 1,505,029	$ 1,346,048
Finite-lived intangible assets, accumulated amortization	(564,188)	(439,642)
Intangible assets, accumulated impairment	(38,507)	(38,507)
Finite-lived intangible assets, net carrying amount	940,841	906,406
Intangible assets, net, exclusive of goodwill	1,163,063	1,128,628
Intangible assets, exclusive of goodwill	1,765,758	1,606,777
Indefinite-lived intangible assets, gross carrying amount	260,729	260,729
Indefinite-lived intangible assets	222,222	222,222
Solid Waste Collection and Transportation Permits
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Indefinite-lived intangible assets, gross carrying amount	158,591	158,591
Indefinite-lived intangible assets	158,591	158,591
Material Recycling Facility Permits
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Indefinite-lived intangible assets, gross carrying amount	42,283	42,283
Indefinite-lived intangible assets	42,283	42,283
Exploration and Production Facility Permits
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Intangible assets, accumulated impairment	(38,507)	(38,507)
Indefinite-lived intangible assets, gross carrying amount	59,855	59,855
Indefinite-lived intangible assets	21,348	21,348
Long-term Franchise Agreements and Contracts
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying amount	550,340	476,833
Finite-lived intangible assets, accumulated amortization	(192,462)	(157,986)
Finite-lived intangible assets, net carrying amount	357,878	318,847
Customer Lists [Member]
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying amount	587,562	530,614
Finite-lived intangible assets, accumulated amortization	(308,427)	(232,461)
Finite-lived intangible assets, net carrying amount	279,135	298,153
Permits and Other [Member]
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying amount	367,127	338,601
Finite-lived intangible assets, accumulated amortization	(63,299)	(49,195)
Finite-lived intangible assets, net carrying amount	$ 303,828	$ 289,406

Intangible Assets, Net (Estimat

Intangible Assets, Net (Estimated Future Amortization Expense of Amortizable Intangible Assets) (Detail) $ in Thousands	Dec. 31, 2019USD ($)
Intangible Assets, Net [Abstract]
For the year ending December 31, 2020	$ 126,000
For the year ending December 31, 2021	109,234
For the year ending December 31, 2022	94,173
For the year ending December 31, 2023	79,710
For the year ending December 31, 2024	$ 68,350

Property and Equipment, Net (Na

Property and Equipment, Net (Narrative) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Landfill [Member]
Property, Plant and Equipment [Line Items]
Landfill depletion expense	$ 225,687	$ 206,404	$ 196,314

Property and Equipment, Net (Pr

Property and Equipment, Net (Property and Equipment) (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment gross	$ 8,963,168	$ 8,052,089
Less accumulated depreciation and depletion	(3,446,821)	(2,883,093)
Property and equipment net	5,516,347	5,168,996
Landfill [Member]
Property, Plant and Equipment [Line Items]
Property and equipment gross	4,334,562	3,981,870
Rolling Stock [Member]
Property, Plant and Equipment [Line Items]
Property and equipment gross	2,011,283	1,736,673
Land, Buildings and Improvements
Property, Plant and Equipment [Line Items]
Property and equipment gross	1,079,420	963,903
Containers [Member]
Property, Plant and Equipment [Line Items]
Property and equipment gross	764,607	682,990
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment gross	749,557	660,961
Construction in Progress
Property, Plant and Equipment [Line Items]
Property and equipment gross	$ 23,739	$ 25,692

Leases (Operating Lease) (Detai

Leases (Operating Lease) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)
Lease cost for operating leases
Operating lease cost	$ 38,710
Operating cash flow information: Cash paid for amounts included in the measurement of lease liabilities	38,226
Non-cash activity: Right-of-use assets obtained in exchange for lease liabilities	$ 10,746
Weighted average remaining lease term	8 years 8 months 12 days
Weighted average discount rate	3.99%

Leases (Future Minimum Lease Pa

Leases (Future Minimum Lease Payments) (Details) $ in Thousands	Dec. 31, 2019USD ($)
Future minimum lease payments as calculated under the new lease guidance
2020	$ 36,718
2021	33,432
2022	32,087
2023	28,750
2024	20,382
Thereafter	75,716
Minimum lease payments	227,085
Less: imputed interest	(37,123)
Present value of minimum lease payments	189,962
Less: current portion of operating lease liabilities	(29,929)
Long-term portion of operating lease liabilities	$ 160,033

Leases (Minimum Lease Payments

Leases (Minimum Lease Payments Under Non-Cancelable Operating Leases) (Details) $ in Thousands	Dec. 31, 2019USD ($)
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2019	$ 37,902
2020	35,204
2021	32,259
2022	30,974
2023	27,882
Thereafter	94,205
Total	$ 258,426

Leases (Rent Expense) (Details)

Leases (Rent Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Summary of rent expense for both short-term agreements and non-cancelable operating lease agreements
Operating Leases, Rent Expense	$ 42,646	$ 43,383

Accrued Liabilities (Detail)

Accrued Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accrued Liabilities [Abstract]
Insurance claims	$ 127,029	$ 119,506
Payroll and payroll-related	71,593	87,136
Interest payable	17,286	16,971
Final capping, closure and post-closure liability - current portion	7,707	26,126
Unrealized cash flow hedge losses	3,680
Cell processing reserve - current portion	3,518	2,835
Environmental remediation reserve - current portion	2,314	3,592
Share-based compensation plan liability - current portion	930	6,209
Other	47,251	53,295
Accrued liabilities	$ 281,308	$ 315,670

Long-Term Debt (Narrative) (Det

Long-Term Debt (Narrative) (Detail) - USD ($)	Apr. 02, 2018	Nov. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Apr. 16, 2019	Nov. 16, 2018	Apr. 20, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Long term debt			$ 4,375,885,000	$ 4,174,693,000
Cash and equivalents			326,738,000	319,305,000
Cash and cash equivalents			423,221,000	403,966,000	$ 553,227,000				$ 168,476,000
Credit Agreement [Member]
Debt Instrument [Line Items]
Credit facility			$ 3,200,000,000
Covenant decription			as of the last day of each fiscal quarter, the ratio of (a) (i) Consolidated Total Funded Debt (as defined in the Credit Agreement) as of such date less (ii) the sum of cash and cash equivalents of the Company and its subsidiaries on a dollar-for-dollar basis as of such date in excess of $50,000 up to a maximum of $200,000 (such that the maximum amount of reduction pursuant to this calculation does not exceed $150,000) to (b) Consolidated EBITDA (as defined in the Credit Agreement), measured for the preceding 12 months (the “Leverage Ratio”), to not more than 3.50 to 1.00 (or 3.75 to 1.00 during material acquisition periods, subject to certain limitations). The Credit Agreement also includes a financial covenant requiring the ratio of Consolidated EBIT (as defined in the Credit Agreement) to Consolidated Total Interest Expense (as defined in the Credit Agreement), in each case, measured for the preceding 12 months, (the “Interest Coverage Ratio”) to be not less than 2.75 to 1.00.
Covenant compliance			As of December 31, 2019 and 2018, the Company was in compliance with all applicable covenants in the Credit Agreement.
Maturity date			Mar. 21, 2023
Credit Agreement [Member] | Letter of Credit [Member]
Debt Instrument [Line Items]
Credit facility			$ 320,000,000
Credit Agreement [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility			1,562,500,000
Long term debt			916,247,000	481,610,000
Credit Agreement [Member] | Term Loan Facility [Member]
Debt Instrument [Line Items]
Credit facility			$ 1,637,500,000
Credit Agreement [Member] | Minimum [Member]
Debt Instrument [Line Items]
Required interest coverage ratio			2.75
Credit Agreement [Member] | Minimum [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Interest rate applicable			2.90%
Credit Agreement [Member] | Maximum [Member]
Debt Instrument [Line Items]
Required leverage ratio during material acquisition period			3.75
Required leverage ratio			3.50
Credit Agreement [Member] | Maximum [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Interest rate applicable			3.18%
Credit Agreement [Member] | Maximum [Member] | Swing Line Loans [Member]
Debt Instrument [Line Items]
Swing line loans			$ 75,000,000
2016 Master Note Purchase Agreement [Member]
Debt Instrument [Line Items]
Maximum limit of aggregate principal amount of notes outstanding			$ 1,500,000,000
2016 Master Note Purchase Agreement [Member] | Minimum [Member]
Debt Instrument [Line Items]
Required interest coverage ratio			2.75
2016 Master Note Purchase Agreement [Member] | Maximum [Member]
Debt Instrument [Line Items]
Required leverage ratio			3.75
Assumed 2008 Note Purchase Agreement [Member]
Debt Instrument [Line Items]
Maximum limit of aggregate principal amount of notes outstanding			$ 1,250,000,000
Assumed 2008 Note Purchase Agreement [Member] | Minimum [Member]
Debt Instrument [Line Items]
Required interest coverage ratio			2.75
Assumed 2008 Note Purchase Agreement [Member] | Maximum [Member]
Debt Instrument [Line Items]
Required leverage ratio			3.75
Tax-Exempt Bonds [Member]
Debt Instrument [Line Items]
Long term debt				15,930,000
Notes Payable to Sellers and Other Third Parties [Member]
Debt Instrument [Line Items]
Long term debt			$ 9,638,000	14,653,000
Notes Payable to Sellers and Other Third Parties [Member] | Minimum [Member]
Debt Instrument [Line Items]
Interest rate			2.75%
Notes Payable to Sellers and Other Third Parties [Member] | Maximum [Member]
Debt Instrument [Line Items]
Interest rate			10.90%
Senior Notes [Member] | 2016 Master Note Purchase Agreement [Member]
Debt Instrument [Line Items]
Debt issuance costs			$ 9,011,000
Covenant compliance			As of December 31, 2019 and 2018, the Company was in compliance with all applicable covenants in the 2016 NPA.
Aggregate principal amount			$ 1,150,000,000
Senior Notes [Member] | Assumed 2008 Note Purchase Agreement [Member]
Debt Instrument [Line Items]
Debt issuance costs			$ 3,863,000
Covenant compliance			As of December 31, 2019 and 2018, the Company was in compliance with all applicable covenants in the 2008 NPA
Senior Notes [Member] | 2017A Senior Notes [Member]
Debt Instrument [Line Items]
Long term debt			$ 400,000,000
Aggregate principal amount								$ 400,000,000
Senior Notes [Member] | Senior Notes due 2018 [Member]
Debt Instrument [Line Items]
Interest rate	4.00%
Maturity of senior debt	$ 50,000,000
Senior Notes [Member] | Senior Notes due 2019 [Member]
Debt Instrument [Line Items]
Long term debt				$ 175,000,000
Senior note year due			2019	2019
Interest rate		5.25%	5.25%	5.25%
Maturity of senior debt		$ 175,000,000
Senior Notes [Member] | Senior Notes due 2021 [Member]
Debt Instrument [Line Items]
Long term debt			$ 100,000,000	$ 100,000,000
Senior note year due			2021	2021
Interest rate			4.64%	4.64%
Senior Notes [Member] | Senior Notes due 2021 [Member]
Debt Instrument [Line Items]
Long term debt			$ 150,000,000	$ 150,000,000
Senior note year due			2021	2021
Maturity date			Jun. 1, 2021
Interest rate			2.39%	2.39%
Senior Notes [Member] | Senior Notes due 2022 [Member]
Debt Instrument [Line Items]
Long term debt			$ 125,000,000	$ 125,000,000
Senior note year due			2022	2022
Interest rate			3.09%	3.09%
Senior Notes [Member] | Senior Notes due 2023 [Member]
Debt Instrument [Line Items]
Long term debt			$ 200,000,000	$ 200,000,000
Senior note year due			2023	2023
Maturity date			Jun. 1, 2023
Interest rate			2.75%	2.75%
Senior Notes [Member] | Senior Notes due 2024 [Member]
Debt Instrument [Line Items]
Long term debt			$ 150,000,000	$ 150,000,000				150,000,000
Senior note year due			2024	2024
Maturity date			Apr. 20, 2024
Interest rate			3.24%	3.24%
Senior Notes [Member] | Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Long term debt			$ 375,000,000	$ 375,000,000
Senior note year due			2025	2025
Interest rate			3.41%	3.41%
Senior Notes [Member] | Senior Notes due 2026 [Member]
Debt Instrument [Line Items]
Long term debt			$ 400,000,000	$ 400,000,000
Senior note year due			2026	2026
Maturity date			Jun. 1, 2026
Interest rate			3.03%	3.03%
Senior Notes [Member] | Senior Notes due 2027 [Member]
Debt Instrument [Line Items]
Long term debt			$ 250,000,000	$ 250,000,000				$ 250,000,000
Senior note year due			2027	2027
Maturity date			Apr. 20, 2027
Interest rate			3.49%	3.49%				3.49%
Senior Notes [Member] | Senior Note due 2028 and 2029[Member]
Debt Instrument [Line Items]
Covenant compliance			As of December 31, 2019, the Company was in compliance with all applicable covenants in the Indenture
Percentage of aggregate principal amount to be repurchased if change of control			100.00%
Senior Notes [Member] | Senior Note due 2028 and 2029[Member] | Maximum [Member]
Debt Instrument [Line Items]
Percentage of aggregate principal amount to be repurchased if change of control			101.00%
Senior Notes [Member] | Senior Notes due 2028 [Member]
Debt Instrument [Line Items]
Long term debt			$ 500,000,000	$ 500,000,000
Debt issuance costs			$ 5,052,000
Senior note year due			2028
Maturity date			Dec. 1, 2028
Interest rate			4.25%
Percentage of aggregate principal amount to be repurchased if change of control			100.00%
Aggregate principal amount							$ 500,000,000
Senior Notes [Member] | Senior Notes due 2029 [Member]
Debt Instrument [Line Items]
Long term debt			$ 500,000,000
Debt issuance costs			$ 4,644,000
Senior note year due			2029
Maturity date			May 1, 2029
Interest rate			3.50%			3.50%
Aggregate principal amount						$ 500,000,000
Senior Notes [Member] | Senior Notes due 2029 [Member] | Minimum [Member]
Debt Instrument [Line Items]
Percentage of aggregate principal amount to be repurchased if change of control			100.00%
Term Loan Facility [Member] | Credit Agreement [Member]
Debt Instrument [Line Items]
Long term debt			$ 700,000,000	1,237,500,000
Interest rate applicable			2.90%
Term Loan Facility [Member] | Credit Agreement [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility maximum increase to borrowing capacity			$ 500,000,000
Maximum amount of increase in commitments under the credit agreement			3,700,000,000
Other Assets [Member] | Credit Agreement [Member]
Debt Instrument [Line Items]
Prepaid expense, debt issuance costs			3,939,000
Debt [Member]
Debt Instrument [Line Items]
Liabilities incurred			$ 95,809,000	210,461,000	$ 56,958,000
Base Rate [Member] | Canadian Prime Rate Loans and Swing Line Loans [Member] | Minimum [Member]
Debt Instrument [Line Items]
Margin rate for loans			0.00%
Base Rate [Member] | Canadian Prime Rate Loans and Swing Line Loans [Member] | Maximum [Member]
Debt Instrument [Line Items]
Margin rate for loans			0.50%
LIBOR [Member] | Credit Agreement [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long term debt			$ 897,000,000	$ 357,000,000
Margin rate for loans			1.10%	1.10%
Interest rate applicable			2.90%	3.62%
LIBOR [Member] | Credit Agreement [Member] | Term Loan Facility [Member]
Debt Instrument [Line Items]
Long term debt			$ 700,000,000	$ 1,237,500,000
Margin rate for loans			1.10%	1.10%
Interest rate applicable			2.90%	3.62%
LIBOR [Member] | Drawing Fees for Bankers Acceptance and BA Equivalent Notes and Letter of Credit [Member] | Minimum [Member]
Debt Instrument [Line Items]
Margin rate for loans			1.00%
LIBOR [Member] | Drawing Fees for Bankers Acceptance and BA Equivalent Notes and Letter of Credit [Member] | Maximum [Member]
Debt Instrument [Line Items]
Margin rate for loans			1.50%
Canadian Bankers Acceptance Loan [Member] | Credit Agreement [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long term debt			$ 19,247,000	$ 124,610,000
Margin rate for loans			1.10%	1.10%
Interest rate applicable			3.18%	3.40%
Credit Agreement Covenant [Member] | Credit Agreement [Member] | Minimum [Member]
Debt Instrument [Line Items]
Cash and equivalents			$ 50,000,000
Credit Agreement Covenant [Member] | Credit Agreement [Member] | Maximum [Member]
Debt Instrument [Line Items]
Cash and equivalents			200,000,000
Credit Agreement Covenant [Member] | Other Assets [Member] | Credit Agreement [Member] | Maximum [Member]
Debt Instrument [Line Items]
Cash and equivalents			$ 150,000,000

Long-Term Debt (Long-Term Debt)

Long-Term Debt (Long-Term Debt) (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Nov. 30, 2019	Apr. 16, 2019	Apr. 20, 2017
Debt Instrument [Line Items]
Total debt	$ 4,375,885,000	$ 4,174,693,000
Less - current portion	(465,000)	(1,786,000)
Less - debt issuance costs	(21,638,000)	(19,442,000)
Long-term debt and notes payable	4,353,782,000	4,153,465,000
Credit Agreement [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Total debt	$ 916,247,000	481,610,000
Credit Agreement [Member] | Revolving Credit Facility [Member] | Minimum [Member]
Debt Instrument [Line Items]
Bearing interest	2.90%
Credit Agreement [Member] | Revolving Credit Facility [Member] | Maximum [Member]
Debt Instrument [Line Items]
Bearing interest	3.18%
Credit Agreement [Member] | Term Loan Facility [Member]
Debt Instrument [Line Items]
Total debt	$ 700,000,000	1,237,500,000
Bearing interest	2.90%
Senior Notes due 2019 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Total debt		$ 175,000,000
Interest rate	5.25%	5.25%	5.25%
Senior note year due	2019	2019
Senior Notes due 2021 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Total debt	$ 100,000,000	$ 100,000,000
Interest rate	4.64%	4.64%
Senior note year due	2021	2021
Senior Notes due 2021 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Total debt	$ 150,000,000	$ 150,000,000
Interest rate	2.39%	2.39%
Senior note year due	2021	2021
Senior Notes due 2022 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Total debt	$ 125,000,000	$ 125,000,000
Interest rate	3.09%	3.09%
Senior note year due	2022	2022
Senior Notes due 2023 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Total debt	$ 200,000,000	$ 200,000,000
Interest rate	2.75%	2.75%
Senior note year due	2023	2023
Senior Notes due 2024 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Total debt	$ 150,000,000	$ 150,000,000			$ 150,000,000
Interest rate	3.24%	3.24%
Senior note year due	2024	2024
Senior Notes due 2025 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Total debt	$ 375,000,000	$ 375,000,000
Interest rate	3.41%	3.41%
Senior note year due	2025	2025
Senior Notes due 2026 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Total debt	$ 400,000,000	$ 400,000,000
Interest rate	3.03%	3.03%
Senior note year due	2026	2026
Senior Notes due 2027 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Total debt	$ 250,000,000	$ 250,000,000			$ 250,000,000
Interest rate	3.49%	3.49%			3.49%
Senior note year due	2027	2027
Senior Notes due 2028 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Total debt	$ 500,000,000	$ 500,000,000
Interest rate	4.25%
Senior note year due	2028
Senior Notes due 2029 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Total debt	$ 500,000,000
Interest rate	3.50%			3.50%
Senior note year due	2029
Tax-Exempt Bonds [Member]
Debt Instrument [Line Items]
Total debt		15,930,000
Notes Payable to Sellers and Other Third Parties [Member]
Debt Instrument [Line Items]
Total debt	$ 9,638,000	$ 14,653,000
Debt, maturity date range, start	2020
Debt, maturity date range, end	2036
Notes Payable to Sellers and Other Third Parties [Member] | Minimum [Member]
Debt Instrument [Line Items]
Interest rate	2.75%
Notes Payable to Sellers and Other Third Parties [Member] | Maximum [Member]
Debt Instrument [Line Items]
Interest rate	10.90%

Long-Term Debt (Details of the

Long-Term Debt (Details of the Company's Credit Agreement) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Line of Credit Facility [Line Items]
Long-term Debt	$ 4,375,885	$ 4,174,693
Revolving Credit Facility [Member] | Credit Agreement [Member]
Line of Credit Facility [Line Items]
Available	$ 538,642	$ 955,779
Commitment - rate applicable	0.12%	0.12%
Long-term Debt	$ 916,247	$ 481,610
Letter of Credit [Member] | Credit Agreement [Member]
Line of Credit Facility [Line Items]
Letter of credit	$ 107,611	$ 125,111
LIBOR [Member] | Revolving Credit Facility [Member] | Credit Agreement [Member]
Line of Credit Facility [Line Items]
Interest rate applicable	2.90%	3.62%
Margin rate for loans	1.10%	1.10%
Long-term Debt	$ 897,000	$ 357,000
LIBOR [Member] | Term Loan Facility [Member] | Credit Agreement [Member]
Line of Credit Facility [Line Items]
Interest rate applicable	2.90%	3.62%
Margin rate for loans	1.10%	1.10%
Long-term Debt	$ 700,000	$ 1,237,500
Canadian Bankers Acceptance Loan [Member] | Revolving Credit Facility [Member] | Credit Agreement [Member]
Line of Credit Facility [Line Items]
Interest rate applicable	3.18%	3.40%
Margin rate for loans	1.10%	1.10%
Long-term Debt	$ 19,247	$ 124,610

Long-Term Debt (Tax-Exempt Bond

Long-Term Debt (Tax-Exempt Bond Financings) (Detail) - Tax-Exempt Bonds [Member] - Lemay Washington Bond [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Jan. 31, 2019
Debt Instrument [Line Items]
Maturity date of bond	Apr. 1, 2033
Outstanding balance of bonds		$ 15,930

Long-Term Debt (Aggregate Contr

Long-Term Debt (Aggregate Contractual Future Principal Payments by Calendar Year on Long-Term Debt) (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Long-Term Debt [Abstract]
2020	$ 465
2021	254,298
2022	125,430
2023	1,816,703
2024	150,483
Thereafter	2,028,506
Total debt	$ 4,375,885	$ 4,174,693

Fair Value of Financial Instr_3

Fair Value of Financial Instruments (Assets and Liabilities Measured at Fair Value on Recurring Basis) (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration	$ (14,038)
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Restricted cash and investments	147,318	$ 131,422
Contingent consideration	(68,984)	(54,615)
Fair Value, Measurements, Recurring | Interest Rate Swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative instrument - net	(39,802)	12,098
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Restricted cash and investments	147,318	131,422
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Interest Rate Swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative instrument - net	(39,802)	12,098
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration	$ (68,984)	$ (54,615)

Fair Value of Financial Instr_4

Fair Value of Financial Instruments (Fair Value for Level 3 Liabilities) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Beginning balance	$ 54,615	$ 47,285
Contingent consideration recorded at acquisition date	14,038	11,669
Payment of contingent consideration recorded at acquisition date	(3,200)	(6,127)
Payment of contingent consideration recorded in earnings		(11)
Adjustments to contingent consideration	1,498	349	$ 17,754
Interest accretion expense	1,852	1,756
Ending balance	68,984	54,615	$ 47,285
Foreign Currency Translation Adjustment [Member]
Foreign currency translation adjustment	$ 181	$ (306)

Commitments and Contingencies_2

Commitments and Contingencies (Narrative) (Detail) gal in Millions, T in Millions	Aug. 10, 2018USD ($)	Mar. 06, 2018USD ($)	Jul. 25, 2017USD ($)	Dec. 31, 2019USD ($)agreementgal	Dec. 31, 2018USD ($)T	Dec. 31, 2014USD ($)
Contingencies And Commitments [Line Items]
Amount of surety bonds to secure asset closure and retirement requirements				$ 661,593,000	$ 619,830,000
Amount of surety bonds to secure performance under collection contracts and landfill operating agreements				$ 419,259,000	357,820,000
Percentage of interest in company that issues financial surety bonds				9.90%
Outstanding amount of financial surety bonds				$ 392,592,000	381,770,000
Environmental remediation reserve - current portion				2,314,000	3,592,000
Environmental remediation reserve-Non-current portion				$ 18,770,000	18,362,000
Total costs accrued as of the balance sheet date for legal settlement loss contingencies					$ 11,043,000
Unrecorded unconditional purchase obligation, remaining volume | gal				49
Purchase commitment				$ 129,373,000
Number of collective bargaining agreements expired or set to expire | agreement				21
Estimated clean up costs						$ 342,000,000
Bridge and Thoroughfare Fee [Member]
Contingencies And Commitments [Line Items]
Loss contingency amount sought		$ 83,000	$ 11,600,000
Fee paid	$ 11,600,000
Noncompliance fee		$ 750
Monthly payment estimate	11,600,000
Chiquita Canyon LLC [Member]
Contingencies And Commitments [Line Items]
Annual tons of waste accepted at landfill | T					2
Estimate of total new fees and other new taxes over life of conditional use permit				$ 300,000,000
Environmental Remediation Expense
Contingencies And Commitments [Line Items]
Required period of monitoring following the clean-up				10 years
Penalties [Member] | Bridge and Thoroughfare Fee [Member]
Contingencies And Commitments [Line Items]
Fee paid	83,000
Monthly payment estimate	83,000
Fees [Member] | Bridge and Thoroughfare Fee [Member]
Contingencies And Commitments [Line Items]
Fee paid	750
Monthly payment estimate	$ 750

Commitments and Contingencies_3

Commitments and Contingencies (Future Minimum Lease Payments) (Detail) $ in Thousands	Dec. 31, 2019USD ($)
Commitments and Contingencies [Abstract]
2019	$ 37,902
2020	35,204
2021	32,259
2022	30,974
2023	27,882
Thereafter	94,205
Total	$ 258,426

Commitments and Contingencies_4

Commitments and Contingencies (Future Minimum Purchase Commitments) (Details) $ in Thousands	Dec. 31, 2019USD ($)
Commitments and Contingencies [Abstract]
2020	$ 76,799
2021	52,574
Total purchase commitment	$ 129,373

Shareholders' Equity (Narrative

Shareholders' Equity (Narrative) (Detail) $ / shares in Units, $ in Thousands	Apr. 26, 2017	Oct. 31, 2019$ / shares	Jun. 30, 2016shares	Dec. 31, 2019USD ($)$ / sharesshares	Sep. 30, 2019$ / shares	Dec. 31, 2019USD ($)shares	Jul. 31, 2019shares	Dec. 31, 2016shares	Dec. 31, 2019USD ($)$ / sharesshares	Dec. 31, 2018USD ($)$ / sharesshares	Dec. 31, 2017USD ($)$ / sharesshares	Dec. 31, 2018USD ($)shares	Dec. 31, 2019USD ($)shares	Jul. 25, 2019shares	Jun. 01, 2016shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share split description									On April 26, 2017, the Company announced that its Board of Directors approved a split of its common shares on a three-for-two basis, which was approved by its shareholders at the Company’s Annual and Special Meeting of Shareholders on May 23, 2017
Stockholders equity stock conversion ratio	1.5
Repurchase of common shares									0	831,704	0
Aggregate cost of common shares repurchase | $										$ 58,928
Aggregate cost of common stock repurchase | $
Cash dividend per share | $ / shares				$ 0.185	$ 0.16				$ 0.665	$ 0.580	$ 0.500
Cash dividend per common share, increase | $ / shares		$ 0.025
Cash dividends on common stock | $									$ 175,067	$ 152,550	$ 131,975
Maximum number of shares authorized for repurchase				13,184,474		13,184,474			13,184,474				13,184,474	13,184,474
Share repurchase plan expiration date						Aug. 7, 2020
Daily repurchase of shares maximum							79,933
Daily Shares Repurchase (as percentage)				25.00%		25.00%			25.00%				25.00%
Average daily trading volume during period							319,734
Common shares, shares issued				263,699,675		263,699,675			263,699,675	263,271,302		263,271,302	263,699,675
Preferred stock, shares issued				0		0			0	0	0	0	0
2016 Incentive Award Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share authorized to be issued as awards				7,500,000		7,500,000			7,500,000				7,500,000
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant expiration									2020
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant expiration									2024
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested deferred RSUs outstanding				247,999		247,999			247,999	264,374	351,570	264,374	247,999
Restricted Stock Units (RSUs) [Member] | 2004 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted in period									0	0	0
Restricted Stock Units (RSUs) [Member] | Progressive Waste Solutions Ltd. [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted in period			0					0	0			0
Performance Shares [Member] | 2017 Performance Based Restricted Share Units Grant One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award											3 years
Performance Shares [Member] | 2017 Performance Based Restricted Share Units Grant Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award											3 years
Performance Shares [Member] | 2018 Performance-Based Restricted Share Units Plan One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award										3 years
Performance Shares [Member] | 2018 Performance-Based Restricted Share Units Plan Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award										3 years
Performance Shares [Member] | 2019 Performance Based Restricted Share Units Plan One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award									3 years
Performance Shares [Member] | 2019 Performance Based Restricted Share Units Plan Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award									3 years
Performance Shares [Member] | Minimum [Member] | 2017 Performance Based Restricted Share Units Grant Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award											1 year
Performance Shares [Member] | Minimum [Member] | 2018 Performance-Based Restricted Share Units Plan Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award										1 year
Performance Shares [Member] | Minimum [Member] | 2019 Performance Based Restricted Share Units Plan Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award									1 year
Performance Shares [Member] | Maximum [Member] | 2017 Performance Based Restricted Share Units Grant Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of share-based compensation arrangements											4 years
Performance Shares [Member] | Maximum [Member] | 2018 Performance-Based Restricted Share Units Plan Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award										4 years
Performance Shares [Member] | Maximum [Member] | 2019 Performance Based Restricted Share Units Plan Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award									4 years
Performance Shares [Member] | Progressive Waste Solutions Ltd. [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted in period													0
Special Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares, shares issued				0		0			0	0	0	0	0
Deferred Share Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested deferred RSUs outstanding				18,970		18,970			18,970	17,176		17,176	18,970
Restricted Share Units and Deferred Share Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Sale of common shares held in trust, shares									48,375	36,244	171,264
Restricted Share Units and Deferred Share Units [Member] | Progressive Waste Solutions Ltd. [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Acquired common shares held in trust				81,514		81,514			81,514				81,514		735,171
Progressive Waste Solutions Ltd. [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested deferred RSUs outstanding				73,884		73,884			73,884	122,259		122,259	73,884
Shares forfeited									964
Progressive Waste Solutions Ltd. [Member] | Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested deferred RSUs outstanding										22,791		22,791
Progressive Waste Solutions Ltd. [Member] | Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option awards granted in period			0					0	0			0

Shareholders' Equity (Common St

Shareholders' Equity (Common Stock Shares Reserved for Issuances) (Detail)	Dec. 31, 2019shares
Class Of Stock [Line Items]
Shares reserved for issuance	7,423,588
Restricted Stock Units Performance Share Units and Warrants [Member]
Class Of Stock [Line Items]
Shares reserved for issuance	1,991,919
2016 Incentive Award Plan [Member]
Class Of Stock [Line Items]
Shares reserved for issuance	5,431,669

Shareholders' Equity (Restricte

Shareholders' Equity (Restricted Stock Units Activity) (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restricted Stock Units (RSUs) [Member]
Schedule of Share based Compensation Arrangements by Share based Payment Award, Equity Instruments, Other Than Options, Restricted Stock Units [Line Items]
Stock units granted	345,127
Weighted average grant-date fair value of award	$ 81.24	$ 69.22	$ 57.09
Total fair value of share units vested	$ 21,136	$ 18,795	$ 16,715
Stock units becoming free of restrictions	416,691
Performance Shares [Member]
Schedule of Share based Compensation Arrangements by Share based Payment Award, Equity Instruments, Other Than Options, Restricted Stock Units [Line Items]
Stock units granted	152,656
Weighted average grant-date fair value of award	$ 80.85	$ 68.77	$ 56.55
Total fair value of share units vested	$ 7,683	$ 5,886	$ 4,098
Stock units becoming free of restrictions	180,258
Deferred Share Units [Member]
Schedule of Share based Compensation Arrangements by Share based Payment Award, Equity Instruments, Other Than Options, Restricted Stock Units [Line Items]
Stock units granted	3,804
Weighted average grant-date fair value of award	$ 83.80	$ 70.47	$ 57.65
Total fair value of share units awarded	$ 319	$ 285	$ 272
Progressive Waste Solutions Ltd. [Member] | Restricted Stock Units (RSUs) [Member]
Schedule of Share based Compensation Arrangements by Share based Payment Award, Equity Instruments, Other Than Options, Restricted Stock Units [Line Items]
Stock units becoming free of restrictions	2,106

Shareholders' Equity (Summary o

Shareholders' Equity (Summary of Activity Related to Restricted Stock Units) (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Unvested shares
Cash settled	(2,010)
Weighted-Average Grant Date Fair Value Per Share
Cash settled	$ 68.83
Restricted Stock Units (RSUs) [Member]
Unvested shares
Outstanding shares beginning balance	264,374	351,570
Outstanding, shares beginning balance	987,563
Granted	345,127
Forfeited	(54,987)
Vested and issued	416,691
Outstanding, shares ending balance	247,999	264,374	351,570
Outstanding, shares, ending balance	861,012	987,563
Weighted-Average Grant Date Fair Value Per Share
Outstanding, beginning balance	$ 56.43
Granted	81.24	$ 69.22	$ 57.09
Forfeited	66.73
Vested and Issued	50.72
Outstanding, ending balance	$ 68.47	$ 56.43
Performance Shares [Member]
Unvested shares
Outstanding, shares beginning balance	532,086
Granted	152,656
Vested and issued	180,258
Outstanding, shares, ending balance	504,484	532,086
Weighted-Average Grant Date Fair Value Per Share
Outstanding, beginning balance	$ 53.43
Granted	80.85	$ 68.77	56.55
Vested and Issued	42.62
Outstanding, ending balance	$ 65.59	$ 53.43
Deferred Share Units [Member]
Unvested shares
Outstanding shares beginning balance	17,176
Granted	3,804
Outstanding, shares ending balance	18,970	17,176
Weighted-Average Grant Date Fair Value Per Share
Outstanding, beginning balance	$ 48.24
Granted	83.80	$ 70.47	$ 57.65
Outstanding, ending balance	$ 53.19
Outstanding, ending balance		$ 48.24
Progressive Waste Solutions Ltd. [Member] | Restricted Stock Units (RSUs) [Member]
Unvested shares
Outstanding shares beginning balance	122,259
Forfeited	(2,352)
Vested and issued	2,106
Cash settled	(46,023)
Outstanding, shares ending balance	73,884	122,259
Progressive Waste Solutions Ltd. [Member] | Performance Shares [Member]
Unvested shares
Outstanding shares beginning balance	22,791
Cash settled	(22,791)
Outstanding, shares ending balance		22,791

Shareholders' Equity (Summary_2

Shareholders' Equity (Summary of Warrant Activity) (Detail) - Stock Purchase Warrants	12 Months Ended
	Dec. 31, 2019$ / sharesshares
Warrant
Outstanding shares beginning balance | shares	268,211
Granted | shares	151,008
Forfeited | shares	(15,728)
Exercised | shares	(25,067)
Outstanding, shares ending balance | shares	378,424
Weighed Average Exercise Price
Outstanding beginning balance | $ / shares	$ 63.49
Granted | $ / shares	91.43
Forfeited | $ / shares	35.05
Exercised | $ / shares	33.38
Outstanding ending balance | $ / shares	$ 77.81

Shareholders' Equity (Summarize

Shareholders' Equity (Summarized Information about Warrants Outstanding) (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Class of Warrant or Right [Line Items]
Outstanding, ending balance	378,424	268,211
Stock Purchase Warrants 2014 Issuance [Member]
Class of Warrant or Right [Line Items]
Grant date	2014
Warrants issued	75,604
Exercise price, lower limit	$ 30.41
Exercise price, upper limit	$ 32.71
Fair value of warrants issued	$ 276
Outstanding, ending balance		15,416
Stock Purchase Warrants 2015 Issuance [Member]
Class of Warrant or Right [Line Items]
Grant date	2015
Warrants issued	136,768
Exercise price, lower limit	$ 28.30
Exercise price, upper limit	$ 36.32
Fair value of warrants issued	$ 1,333
Outstanding, ending balance	21,515	45,978
Stock Purchase Warrants 2016 Issuance [Member]
Class of Warrant or Right [Line Items]
Grant date	2016
Warrants issued	15,666
Exercise price, lower limit	$ 42.22
Exercise price, upper limit	$ 51.55
Fair value of warrants issued	$ 189
Outstanding, ending balance	7,158	7,440
Stock Purchase Warrants 2017 Issuance [Member]
Class of Warrant or Right [Line Items]
Grant date	2017
Warrants issued	35,382
Exercise price, lower limit	$ 53.65
Exercise price, upper limit	$ 69.96
Fair value of warrants issued	$ 595
Outstanding, ending balance	35,382	35,382
Stock Purchase Warrants 2018 Issuance [Member]
Class of Warrant or Right [Line Items]
Grant date	2018
Warrants issued	163,995
Exercise price, lower limit	$ 70.91
Exercise price, upper limit	$ 80.90
Fair value of warrants issued	$ 2,591
Outstanding, ending balance	163,361	163,995
Stock Purchase Warrants 2019 Issuance [Member]
Class of Warrant or Right [Line Items]
Grant date	2019
Warrants issued	151,008
Exercise price, lower limit	$ 74.25
Exercise price, upper limit	$ 95.61
Fair value of warrants issued	$ 2,634
Outstanding, ending balance	151,008

Shareholders' Equity (Summary_3

Shareholders' Equity (Summary of Vesting Activity Related to Restricted Share Units) (Details)	12 Months Ended
	Dec. 31, 2019shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Cash settled	(2,010)
Restricted Stock Units (RSUs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vested over remaining service period	416,691
Forfeited	(54,987)
Restricted Stock Units (RSUs) [Member] | Progressive Waste Solutions Ltd. [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vested, shares beginning balance	120,153
Vested over remaining service period	2,106
Cash settled	(46,023)
Forfeited	(2,352)
Vested, shares ending balance	73,884
Performance Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vested over remaining service period	180,258
Performance Shares [Member] | Progressive Waste Solutions Ltd. [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Cash settled	(22,791)

Shareholders' Equity (Summary_4

Shareholders' Equity (Summary of Stock Option Activity and Related Information) (Detail) - Progressive Waste Solutions Ltd. [Member]	12 Months Ended
	Dec. 31, 2019shares
Number of Shares (Options)
Outstanding, shares beginning balance	165,156
Cash settled	(38,995)
Outstanding, shares ending balance	126,161

Other Comprehensive Income (L_3

Other Comprehensive Income (Loss) (Components of Other Comprehensive Income (Loss)) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amount of Gain or (Loss) Recognized from AOCIL into Earnings, Net of Tax	$ (5,900)	$ (9,071)	$ 4,174
Amount of Gain or (Loss) Recognized as AOCIL on Derivatives, Net of Tax	(32,247)	1,105	4,754
Foreign currency translation adjustment, gross	101,970	(175,233)	142,486
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Total	101,970	(175,233)	142,486
Other Comprehensive Income (Loss), before Tax	50,070	(185,995)	157,270
Other Comprehensive Income (Loss), Tax	(13,753)	(2,796)	5,856
Other comprehensive income (loss), net of tax	63,823	(183,199)	151,414
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amount of Gain or (Loss) Recognized from AOCIL into Earnings, Net of Tax	(5,900)	(9,071)	4,174
Amount of Gain or (Loss) Recognized as AOCIL on Derivatives, Net of Tax	(32,247)	1,105	4,754
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Total	101,970	(175,233)	142,486
Interest Rate Swap [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	(8,027)	(5,669)	2,805
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax	2,127	1,502	(743)
Amount of Gain or (Loss) Recognized from AOCIL into Earnings, Net of Tax	(5,900)	(4,167)	2,062
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax	(43,873)	(1,213)	7,835
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, Tax	11,626	321	(4,040)
Amount of Gain or (Loss) Recognized as AOCIL on Derivatives, Net of Tax	$ (32,247)	(892)	3,795
Fuel [Member] | Commodity Contract [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax		(6,531)	2,818
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax		1,627	(706)
Amount of Gain or (Loss) Recognized from AOCIL into Earnings, Net of Tax		(4,904)	2,112
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax		2,651	1,326
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, Tax		(654)	(367)
Amount of Gain or (Loss) Recognized as AOCIL on Derivatives, Net of Tax		$ 1,997	$ 959

Other Comprehensive Income (L_4

Other Comprehensive Income (Loss) (Amounts Included in Accumulated Other Comprehensive Income (Loss)) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Components of Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity Attributable to Parent, Beginning Balance	$ 6,454,608
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	101,970	$ (175,233)	$ 142,486
Stockholders' Equity Attributable to Parent, Ending Balance	6,933,504	6,454,608
Foreign currency translation adjustment	101,970	(175,233)	142,486
Accumulated Other Comprehensive Income (Loss) [Member]
Components of Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity Attributable to Parent, Beginning Balance	(74,786)	108,413
Amounts reclassified into earnings	(5,900)	(9,071)
Change in fair value	(32,247)	1,105
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	101,970	(175,233)	142,486
Stockholders' Equity Attributable to Parent, Ending Balance	(10,963)	(74,786)	108,413
Foreign currency translation adjustment	101,970	(175,233)	142,486
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member] | Interest Rate Swap [Member]
Components of Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity Attributable to Parent, Beginning Balance	8,892	13,951
Amounts reclassified into earnings	(5,900)	(4,167)
Change in fair value	(32,247)	(892)
Stockholders' Equity Attributable to Parent, Ending Balance	(29,255)	8,892	13,951
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member] | Foreign Currency Translation Adjustment [Member]
Components of Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity Attributable to Parent, Beginning Balance	(83,678)	91,555
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	101,970	(175,233)
Stockholders' Equity Attributable to Parent, Ending Balance	18,292	(83,678)	91,555
Foreign currency translation adjustment	$ 101,970	(175,233)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member] | Fuel [Member] | Commodity Contract [Member]
Components of Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity Attributable to Parent, Beginning Balance		2,907
Amounts reclassified into earnings		(4,904)
Change in fair value		$ 1,997
Stockholders' Equity Attributable to Parent, Ending Balance			$ 2,907

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Detail) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 29, 2017
Operating Loss Carryforwards [Line Items]
Increase (decrease) to tax expense			$ (3,057)
Deferred income tax expense			$ 68,779
Statutory income tax rate	21.00%	21.00%	21.00%	35.00%
Non-deductible expenses, other		$ 3,805
Unrecognized tax benefits	$ 0	0	$ 0	$ 0
Net deferred income tax expense (benefit) from enactment of tax reform			5,572	(269,804)
Deferred income tax expense from foreign earnings transition tax				62,350
Non-deductible expenses, impairment				$ 11,825
Deferred tax liabilities, undistributed earnings		1,434,805
Deferred tax liability not recognized, undistributed earnings of foreign subsidiaries		319,046
Undistributed earnings		$ 2,609,805
Internal Revenue Service [Member]
Operating Loss Carryforwards [Line Items]
Statutory income tax rate					35.00%
Canada Revenue Agency [Member]
Operating Loss Carryforwards [Line Items]
Foreign Statutory income tax rate		27.00%
Operating loss carryforwards		$ 29,460
Adjustment [Member]
Operating Loss Carryforwards [Line Items]
Deferred income tax expense			$ 6,429

Income Taxes (Income (Loss) Bef

Income Taxes (Income (Loss) Before Provision (Benefit) for Income Taxes) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Taxes [Abstract]
U.S.	$ 477,203	$ 491,506	$ 301,962
Non-U.S.	228,688	215,634	206,548
Income before income tax provision	$ 705,891	$ 707,140	$ 508,510

Income Taxes (Provision Benefit

Income Taxes (Provision Benefit for Income Taxes) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current:
U.S. Federal	$ 45,475	$ 37,419	$ 45,089
State	27,528	27,057	19,848
Non - U.S.	11,570	17,651	18,537
Current income tax expense (benefit), total	84,573	82,127	83,474
Deferred:
U.S. Federal	58,291	85,926	(203,131)
State	6,331	1,991	7,534
Non - U.S.	(9,985)	(10,058)	43,213
Deferred income tax expense (benefit), total	54,637	77,859	(152,384)
Provision (Benefit) for income taxes	$ 139,210	$ 159,986	$ (68,910)

Income Taxes (Differences betwe

Income Taxes (Differences between Income Tax Provision in Statements of Net Income and Income Tax Provision Computed at Federal Statutory Rate) (Detail)	1 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Taxes [Abstract]
U.S. federal statutory rate	21.00%	21.00%	21.00%	35.00%
State taxes, net of federal benefit		4.40%	4.40%	4.10%
Deferred income tax liability adjustments		0.60%	(0.20%)	0.50%
Effect of international operations		(6.30%)	(3.90%)	(14.60%)
Enactment of the Tax Act				(53.10%)
Deferred tax on undistributed earnings			0.009	0.123
Goodwill impairment				2.10%
Other			0.40%	0.10%
Effective income tax rate, total		19.70%	22.60%	(13.60%)

Income Taxes (Significant Compo

Income Taxes (Significant Components of Deferred Income Tax Assets and Liabilities) (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Deferred income tax assets:
Accrued expenses	$ 23,536	$ 26,128
Compensation	17,532	19,830
Contingent liabilities	15,228	14,043
Finance costs		2,329
Tax credits and loss carryforwards	18,693	20,438
Other	10,548
Gross deferred income tax assets	85,537	82,768
Less: Valuation allowance
Total deferred income tax assets	85,537	82,768
Deferred income tax liabilities:
Goodwill and other intangibles	(311,404)	(283,671)
Property and equipment	(497,768)	(461,071)
Landfill closure/post-closure	(12,159)	(8,892)
Prepaid expenses	(8,542)	(11,581)
Interest rate and fuel hedges		(3,206)
Investment in subsidiaries	(69,597)	(69,383)
Other	(4,689)	(4,997)
Total deferred income tax liabilities	(904,159)	(842,801)
Net deferred income tax liability	$ (818,622)	$ (760,033)

Segment Reporting (Narrative) (

Segment Reporting (Narrative) (Detail)	12 Months Ended
	Dec. 31, 2019segment
Segment Reporting [Abstract]
Number of major customers	0
Number of geographic operating segments	5
Number of reportable segments	6

Segment Reporting (Summary of F

Segment Reporting (Summary of Financial Information Concerning Company's Reportable Segments) (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Revenue	$ 1,361,960	$ 1,412,444	$ 1,369,639	$ 1,244,637	$ 1,261,732	$ 1,281,110	$ 1,239,968	$ 1,140,131	$ 5,388,679	$ 4,922,941	$ 4,630,488
Segment EBITDA									1,643,644	1,532,849	1,416,075
Depreciation and amortization									743,918	680,487	632,484
Capital expenditures									666,089	546,145	479,287
Total assets	13,737,695				12,627,329				13,737,695	12,627,329	12,014,681
Intercompany Revenues [Member]
Segment Reporting Information [Line Items]
Revenue									(787,994)	(709,889)	(640,886)
Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue									6,176,673	5,632,830	5,271,374
Segment EBITDA									1,659,082	1,541,060	1,448,576
Eastern [Member]
Segment Reporting Information [Line Items]
Revenue									1,268,964	1,071,990	941,827
Segment EBITDA									330,578	295,016	269,106
Depreciation and amortization									204,221	166,715	135,737
Capital expenditures									154,218	136,214	100,025
Total assets	3,099,283				2,673,316				3,099,283	2,673,316	2,009,328
Eastern [Member] | Intercompany Revenues [Member]
Segment Reporting Information [Line Items]
Revenue									(255,684)	(224,833)	(178,394)
Eastern [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue									1,524,648	1,296,823	1,120,221
Southern [Member]
Segment Reporting Information [Line Items]
Revenue									1,192,922	1,122,548	1,115,864
Segment EBITDA									305,999	276,791	258,560
Depreciation and amortization									160,038	153,923	151,417
Capital expenditures									141,157	97,442	117,441
Total assets	2,990,247				2,892,994				2,990,247	2,892,994	2,718,296
Southern [Member] | Intercompany Revenues [Member]
Segment Reporting Information [Line Items]
Revenue									(162,831)	(150,485)	(146,283)
Southern [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue									1,355,753	1,273,033	1,262,147
Segment EBITDA									305,999	276,791	258,560
Western [Member]
Segment Reporting Information [Line Items]
Revenue									1,098,849	1,043,928	1,007,230
Segment EBITDA									338,563	318,401	323,648
Depreciation and amortization									102,067	95,400	95,724
Capital expenditures									147,893	125,112	100,000
Total assets	1,718,015				1,596,129				1,718,015	1,596,129	1,573,955
Western [Member] | Intercompany Revenues [Member]
Segment Reporting Information [Line Items]
Revenue									(135,820)	(126,454)	(119,916)
Western [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue									1,234,669	1,170,382	1,127,146
Segment EBITDA									338,563	318,401	323,648
Central [Member]
Segment Reporting Information [Line Items]
Revenue									838,584	711,554	645,554
Segment EBITDA									292,111	259,794	241,972
Depreciation and amortization									106,391	89,001	79,460
Capital expenditures									116,831	91,646	79,544
Total assets	1,885,468				1,506,326				1,885,468	1,506,326	1,312,317
Central [Member] | Intercompany Revenues [Member]
Segment Reporting Information [Line Items]
Revenue									(119,555)	(103,966)	(88,488)
Central [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue									958,139	815,520	734,042
Segment EBITDA									292,111	259,794	241,972
Canada [Member]
Segment Reporting Information [Line Items]
Revenue									733,282	727,213	728,777
Segment EBITDA									256,405	261,233	264,693
Depreciation and amortization									113,944	124,155	121,174
Capital expenditures									61,119	66,319	62,690
Total assets	2,490,291				2,412,971				2,490,291	2,412,971	2,677,557
Canada [Member] | Intercompany Revenues [Member]
Segment Reporting Information [Line Items]
Revenue									(102,321)	(96,776)	(99,978)
Canada [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue									835,603	823,989	828,755
Segment EBITDA									256,405	261,233	264,693
Exploration and Production [Member]
Segment Reporting Information [Line Items]
Revenue									256,078	245,708	191,236
Segment EBITDA									135,426	129,825	90,597
Depreciation and amortization									48,929	44,175	42,500
Capital expenditures									36,970	25,937	12,274
Total assets	962,202				969,808				962,202	969,808	981,980
Exploration and Production [Member] | Intercompany Revenues [Member]
Segment Reporting Information [Line Items]
Revenue									(11,783)	(7,375)	(7,827)
Exploration and Production [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue									267,861	253,083	199,063
Segment EBITDA									135,426	129,825	90,597
Corporate [Member]
Segment Reporting Information [Line Items]
Segment EBITDA									(15,438)	(8,211)	(32,501)
Depreciation and amortization									8,328	7,118	6,472
Capital expenditures									7,901	3,475	7,313
Total assets	$ 592,189				$ 575,785				$ 592,189	$ 575,785	$ 741,248

Segment Reporting (Changes in G

Segment Reporting (Changes in Goodwill by Reportable Segment) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 5,031,685	$ 4,681,774
Goodwill acquired	407,068	466,441	$ 311,632
Goodwill divested	(845)
Goodwill adjustment for assets sold		10,181
Impact of changes in foreign currency	72,943	(126,711)
Goodwill, Ending Balance	5,510,851	5,031,685	4,681,774
Eastern [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	1,126,486	804,133
Goodwill transferred		(16,869)
Goodwill acquired	204,694	339,222
Goodwill, Ending Balance	1,331,180	1,126,486	804,133
Southern [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	1,517,610	1,436,320
Goodwill acquired	11,460	71,109
Goodwill divested	(845)
Goodwill adjustment for assets sold		10,181
Goodwill, Ending Balance	1,528,225	1,517,610	1,436,320
Western [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	398,174	397,508
Goodwill acquired	1,863	666
Goodwill, Ending Balance	400,037	398,174	397,508
Central [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	540,435	468,275
Goodwill transferred		16,869
Goodwill acquired	189,035	55,291
Goodwill, Ending Balance	729,470	540,435	468,275
Canada [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	1,448,980	1,575,538
Goodwill acquired	16	153
Impact of changes in foreign currency	72,943	(126,711)
Goodwill, Ending Balance	1,521,939	$ 1,448,980	1,575,538
Exploration and Production [Member]
Goodwill [Line Items]
Impairment loss			$ (77,343)
Goodwill, Ending Balance	$ 0

Segment Reporting (Property and

Segment Reporting (Property and Equipment, Net Relating to Operations) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Property and equipment	$ 5,516,347	$ 5,168,996
United States [Member]
Segment Reporting Information [Line Items]
Property and equipment	4,862,557	4,516,966
Canada [Member]
Segment Reporting Information [Line Items]
Property and equipment	$ 653,790	$ 652,030

Segment Reporting (Reconciliati

Segment Reporting (Reconciliation of Primary Measure of Segment Profitability to Income before Income Tax Provision) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment EBITDA	$ 1,643,644	$ 1,532,849	$ 1,416,075
Depreciation	(618,396)	(572,708)	(530,187)
Amortization of intangibles	(125,522)	(107,779)	(102,297)
Impairments and other operating items	(61,948)	(20,118)	(156,493)
Interest expense	(147,368)	(132,104)	(125,297)
Interest income	9,777	7,170	5,173
Other income (expense), net	5,704	(170)	1,536
Income before income tax provision	705,891	707,140	508,510
Operating Segments [Member]
Segment EBITDA	1,659,082	1,541,060	1,448,576
Eastern [Member]
Segment EBITDA	330,578	295,016	269,106
Southern [Member]
Segment EBITDA	305,999	276,791	258,560
Southern [Member] | Operating Segments [Member]
Segment EBITDA	305,999	276,791	258,560
Western [Member]
Segment EBITDA	338,563	318,401	323,648
Western [Member] | Operating Segments [Member]
Segment EBITDA	338,563	318,401	323,648
Canada [Member]
Segment EBITDA	256,405	261,233	264,693
Canada [Member] | Operating Segments [Member]
Segment EBITDA	256,405	261,233	264,693
Central [Member]
Segment EBITDA	292,111	259,794	241,972
Central [Member] | Operating Segments [Member]
Segment EBITDA	292,111	259,794	241,972
Exploration and Production [Member]
Segment EBITDA	135,426	129,825	90,597
Exploration and Production [Member] | Operating Segments [Member]
Segment EBITDA	135,426	129,825	90,597
Corporate [Member]
Segment EBITDA	$ (15,438)	$ (8,211)	$ (32,501)

Net Income Per Share Informat_3

Net Income Per Share Information (Basic and Diluted Net Income Per Common Share) (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Numerator:
Net income attributable to Waste Connections for basic and diluted earnings per share	$ 133,262	$ 159,109	$ 148,848	$ 125,622	$ 132,478	$ 150,843	$ 138,682	$ 124,869	$ 566,841	$ 546,871	$ 576,817
Denominator:
Basic shares outstanding									263,792,693	263,650,155	263,682,608
Dilutive effect of equity-based awards									733,868	745,463	619,803
Diluted shares outstanding									264,526,561	264,395,618	264,302,411

Employee Benefit Plans (Narrati

Employee Benefit Plans (Narrative) (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)agreement	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)
Employee Benefit Plan [Line Items]
Percentage of every dollar of a participating employee's pre-tax contributions as matching contribution to 401(k) Plan	100.00%
Maximum percentage of contribution	5.00%
Number of multiemployer pension plans | agreement	11
Deferred Compensation Plan [Member]
Employee Benefit Plan [Line Items]
Percentage of every dollar of a participating employee's pre-tax contributions as matching contribution to 401(k) Plan	100.00%	50.00%	50.00%
Percentage of employee's eligible compensation that represents the maximum amount of employer matching contribution to plan	5.00%	6.00%	6.00%
Percentage of salary that may voluntarily be elected to be deferred	80.00%
Percentage of bonuses, commissions and restricted share unit grants that may voluntarily be elected to be deferred	100.00%
Total liability for deferred compensation	$ 37,707	$ 32,024
Voluntary Savings And Investment Plan
Employee Benefit Plan [Line Items]
Total employer expenses, including employer matching contributions	$ 26,111	$ 12,055	$ 14,703
Maximum [Member]
Employee Benefit Plan [Line Items]
Percentage of employee's eligible compensation that represents the maximum amount of employer matching contribution to plan	5.00%
Maximum [Member] | Retirement Savings Plan [Member]
Employee Benefit Plan [Line Items]
Contribution to a deferred profit sharing plan	4.00%

Employee Benefit Plans (Plan Co

Employee Benefit Plans (Plan Contributions) (Details) - USD ($) $ in Thousands	1 Months Ended	9 Months Ended	12 Months Ended
	Apr. 30, 2017	Dec. 31, 2019	Dec. 31, 2019	Sep. 30, 2019	Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2017
Multiemployer Plans [Line Items]
Company contributions			$ 13,686		$ 13,026	$ 12,038
Local 731 I.b. Of T. Private Scavengers Garage Attendants And Textile Maintenance Pension Trust Fund [Member]
Multiemployer Plans [Line Items]
Registration number			36-6513567 - 001
Pension Protection Act zone status				Green			Green
FIP/RP status			NA
Company contributions			$ 4,570		$ 4,600	4,342
Western Conference of Teamsters Pension Trust [Member]
Multiemployer Plans [Line Items]
Registration number			91-6145047 - 001
Pension Protection Act zone status			Green		Green
FIP/RP status			NA
Company contributions			$ 4,550		$ 4,399	4,191
Collective-bargaining agreement, expiration date, start			Dec. 31, 2019
Collective-bargaining agreement, expiration date, end			Jul. 31, 2022
International Union of Operating Engineers Pension Trust [Member]
Multiemployer Plans [Line Items]
Registration number			85512-1
Pension Protection Act zone status	Green
FIP/RP status			NA
Company contributions			$ 238		$ 224	219
Collective-bargaining agreement, expiration date, start			Mar. 31, 2020
Collective-bargaining agreement, expiration date, end			Mar. 31, 2021
Multi-Sector Pension Plan [Member]
Multiemployer Plans [Line Items]
Registration number			1085653
Pension Protection Act zone status			Green		Green
FIP/RP status			NA
Company contributions			$ 202		$ 191	228
Collective-bargaining agreement, expiration date			Dec. 31, 2018
Local 813 Pension Trust Fund [Member]
Multiemployer Plans [Line Items]
Registration number			13-1975659 - 001
Pension Protection Act zone status			Red		Red
FIP/RP status			Implemented
Company contributions			$ 281		$ 165	$ 158
Collective-bargaining agreement, expiration date			Nov. 30, 2019
Midwest Operating Engineers Pension Plan [Member]
Multiemployer Plans [Line Items]
Registration number			36-6140097 - 001
Pension Protection Act zone status		Green				Yellow
FIP/RP status			NA
Company contributions			$ 339		$ 289	$ 207
Collective-bargaining agreement, expiration date			Oct. 31, 2020
Locals 302 & 612 of the IOUE - Employers Construction Industry Retirement Plan [Member]
Multiemployer Plans [Line Items]
Registration number			91-6028571 - 001
Pension Protection Act zone status			Green		Green
FIP/RP status			NA
Company contributions			$ 290		$ 284	275
Collective-bargaining agreement, expiration date			Nov. 16, 2022
Suburban Teamsters of Northern Illinois Pension Fund [Member]
Multiemployer Plans [Line Items]
Registration number			36-6155778 - 001
Pension Protection Act zone status			Green		Yellow
FIP/RP status			NA
Company contributions			$ 1,844		$ 1,569	877
Collective-bargaining agreement, expiration date			Jan. 31, 2024
Collective-bargaining agreement, expiration date, start			Jan. 31, 2019
Teamster Local 301 Pension Fund [Member]
Multiemployer Plans [Line Items]
Registration number			36-6492992 - 001
Pension Protection Act zone status			Green		Green
FIP/RP status			NA
Company contributions			$ 624		$ 581	489
Collective-bargaining agreement, expiration date			Sep. 30, 2023
Automobile Mechanics' Local No. 701 Union and Industry Pension Fund [Member]
Multiemployer Plans [Line Items]
Registration number			36-6042061 - 001
Pension Protection Act zone status			Yellow		Yellow
FIP/RP status			Implemented
Company contributions			$ 492		$ 484	837
Collective-bargaining agreement, expiration date			Dec. 31, 2022
IAM National Pension Fund [Member]
Multiemployer Plans [Line Items]
Registration number			51-6031295 - 002
Pension Protection Act zone status			Green		Green
FIP/RP status			NA
Company contributions			$ 256		$ 240	$ 215
Collective-bargaining agreement, expiration date			Dec. 31, 2022
Local 731, I.B. of T., Private Scavengers and Garage Attendants Pension Trust Fund [Member]
Multiemployer Plans [Line Items]
Collective-bargaining agreement, expiration date			Sep. 30, 2023

Selected Quarterly Financial _3

Selected Quarterly Financial Data (Narrative) (Detail) - USD ($) $ in Thousands	3 Months Ended				12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Quarterly Financial Data [Line Items]
Gain or loss recognized on assets held for sale				$ 6,257
Gain (Loss) on Contract Termination			$ 12,230
Impairment charges						$ 0
Write down of assets	$ (25,798)
Acquisition related costs					$ 12,335	8,607	$ 5,700
Net deferred income tax expense (benefit) from enactment of tax reform						5,572	(269,804)
Indefinite-lived intangible asset write-down					0	0	0
Increase in contingent consideration					1,498	349	17,754
Share-based compensation expense					42,671	43,803	39,361
Share-based compensation expense, net of taxes					31,926	32,774	25,608
Total costs accrued as of the balance sheet date for legal settlement loss contingencies						$ 11,043
Officer [Member]
Quarterly Financial Data [Line Items]
Share-based compensation expense				$ 5,005
Exploration and Production [Member]
Quarterly Financial Data [Line Items]
Impairment charges		$ 8,000			$ 8,000
Goodwill write-down							77,343
Central [Member]
Quarterly Financial Data [Line Items]
Impairment charges							$ 11,038

Selected Quarterly Financial _4

Selected Quarterly Financial Data (Quarterly Results of Operations (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Selected Quarterly Financial Data [Abstract]
Revenues	$ 1,361,960	$ 1,412,444	$ 1,369,639	$ 1,244,637	$ 1,261,732	$ 1,281,110	$ 1,239,968	$ 1,140,131	$ 5,388,679	$ 4,922,941	$ 4,630,488
Operating income (loss)	194,184	236,600	222,134	184,860	199,980	232,869	210,688	188,707	837,778	832,244	627,098
Net income	133,191	159,074	148,839	125,577	132,543	150,766	138,814	125,032	566,681	547,154	577,420
Net income (loss) attributable to Waste Connections	$ 133,262	$ 159,109	$ 148,848	$ 125,622	$ 132,478	$ 150,843	$ 138,682	$ 124,869	$ 566,841	$ 546,871	$ 576,817
Basic income (loss) per common share attributable to Waste Connections' common shareholders	$ 0.51	$ 0.60	$ 0.56	$ 0.48	$ 0.50	$ 0.57	$ 0.53	$ 0.47	$ 2.15	$ 2.07	$ 2.19
Diluted income (loss) per common share attributable to Waste Connections' common shareholders	$ 0.50	$ 0.60	$ 0.56	$ 0.48	$ 0.50	$ 0.57	$ 0.52	$ 0.47	$ 2.14	$ 2.07	$ 2.18

Subsequent Events (Details)

Subsequent Events (Details) - Subsequent Event [Member] - USD ($)	Feb. 12, 2020	Jan. 23, 2020
Subsequent Event [Line Items]
Dividends, declared date	Feb. 12, 2020
Dividends per share amount	$ 0.185
Dividends, date to be paid	Mar. 12, 2020
Dividends, date of record	Feb. 27, 2020
Senior Notes Due 2030 [Member] | Senior Notes [Member]
Subsequent Event [Line Items]
Aggregate principal amount		$ 600,000,000
Interest rate of senior notes		2.60%
Maturity date		Feb. 1, 2030

Valuation and Qualifying Acco_2

Valuation and Qualifying Accounts (Detail) - Allowance for Doubtful Accounts - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation allowances and reserves, balance	$ 16,760	$ 17,154	$ 13,160
Valuation allowances and reserves, charged to cost and expense	11,973	13,814	14,363
Valuation allowances and reserves, deductions	(12,301)	(14,208)	(10,369)
Valuation allowances and reserves, balance	$ 16,432	$ 16,760	$ 17,154