Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Segment and Related Information - Summary (Detail) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Operating revenues	$ 3,842	$ 3,822	$ 3,739	$ 3,511	$ 3,652	$ 3,716	$ 3,677	$ 3,440	$ 14,914	$ 14,485	$ 13,609
Income from operations	767	$ 699	$ 715	$ 608	704	$ 701	$ 673	$ 558	2,789	2,636	2,296
Depreciation and amortization									1,477	1,376	1,301
Capital Expenditures									1,671	1,568	1,347
Total Assets	22,650				21,829				22,650	21,829	20,859
Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating revenues									18,024	17,370	16,246
Total Assets	22,896				22,116				22,896	22,116	21,137
Intercompany Operating Revenues [Member]
Segment Reporting Information [Line Items]
Operating revenues									(3,110)	(2,885)	(2,637)
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Income from operations									(540)	(585)	(550)
Depreciation and amortization									30	45	56
Capital Expenditures									200	92	45
Total Assets	1,487				1,327				1,487	1,327	1,401
Elimination of Intercompany Investments and Advances [Member]
Segment Reporting Information [Line Items]
Total Assets	(246)				(287)				(246)	(287)	(278)
Operating Group Total [Member]
Segment Reporting Information [Line Items]
Operating revenues									14,914	14,485	13,609
Operating Group Total [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating revenues									18,024	17,370	16,246
Income from operations									3,329	3,221	2,846
Depreciation and amortization									1,447	1,331	1,245
Capital Expenditures									1,471	1,476	1,302
Total Assets	21,409				20,789				21,409	20,789	19,736
Operating Group Total [Member] \| Intercompany Operating Revenues [Member]
Segment Reporting Information [Line Items]
Operating revenues									(3,110)	(2,885)	(2,637)
Solid Waste [Member]
Segment Reporting Information [Line Items]
Operating revenues									12,622	12,167	11,516
Solid Waste [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating revenues									15,537	14,832	13,968
Income from operations									3,395	3,289	2,946
Depreciation and amortization									1,356	1,228	1,144
Capital Expenditures									1,399	1,383	1,198
Total Assets	19,838				19,004				19,838	19,004	18,247
Solid Waste [Member] \| Intercompany Operating Revenues [Member]
Segment Reporting Information [Line Items]
Operating revenues									(2,915)	(2,665)	(2,452)
Tier 1 [Member]
Segment Reporting Information [Line Items]
Operating revenues									4,805	4,574	4,330
Tier 1 [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating revenues									5,868	5,576	5,241
Income from operations									1,642	1,538	1,430
Depreciation and amortization									510	451	424
Capital Expenditures									595	603	452
Total Assets	6,958				6,528				6,958	6,528	6,188
Tier 1 [Member] \| Intercompany Operating Revenues [Member]
Segment Reporting Information [Line Items]
Operating revenues									(1,063)	(1,002)	(911)
Tier 2 [Member]
Segment Reporting Information [Line Items]
Operating revenues									2,135	2,116	1,996
Tier 2 [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating revenues									2,622	2,559	2,400
Income from operations									542	552	522
Depreciation and amortization									232	203	190
Capital Expenditures									257	185	157
Total Assets	3,761				3,749				3,761	3,749	3,562
Tier 2 [Member] \| Intercompany Operating Revenues [Member]
Segment Reporting Information [Line Items]
Operating revenues									(487)	(443)	(404)
Tier 3 [Member]
Segment Reporting Information [Line Items]
Operating revenues									5,682	5,477	5,190
Tier 3 [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating revenues									7,047	6,697	6,327
Income from operations									1,211	1,199	994
Depreciation and amortization									614	574	530
Capital Expenditures									547	595	589
Total Assets	9,119				8,727				9,119	8,727	8,497
Tier 3 [Member] \| Intercompany Operating Revenues [Member]
Segment Reporting Information [Line Items]
Operating revenues									(1,365)	(1,220)	(1,137)
Other [Member]
Segment Reporting Information [Line Items]
Operating revenues									2,292	2,318	2,093
Other [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating revenues									2,487	2,538	2,278
Income from operations									(66)	(68)	(100)
Depreciation and amortization									91	103	101
Capital Expenditures									72	93	104
Total Assets	$ 1,571				$ 1,785				1,571	1,785	1,489
Other [Member] \| Intercompany Operating Revenues [Member]
Segment Reporting Information [Line Items]
Operating revenues									$ (195)	$ (220)	$ (185)