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Segment and Related Information - Summary (Detail) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting Information [Line Items]
Operating revenues	$ 4,476		$ 3,561	$ 8,588	$ 7,290
Income from operations	791		527	1,441	1,100
Asset impairments		$ 6	61		61
Landfills and Oil Field Waste Injection Facility [Member]
Segment Reporting Information [Line Items]
Asset impairments			41
Landfill [Member]
Segment Reporting Information [Line Items]
Asset impairments			20
Operating Group Total [Member]
Segment Reporting Information [Line Items]
Operating revenues	4,476		3,561	8,588	7,290
Income from operations	1,060		712	1,996	1,532
Solid Waste [Member]
Segment Reporting Information [Line Items]
Operating revenues	3,779		3,032	7,249	6,236
Income from operations	1,056		722	1,974	1,567
Tier 1 [Member]
Segment Reporting Information [Line Items]
Operating revenues	986		797	1,873	1,639
Income from operations	350		270	657	558
Tier 2 [Member]
Segment Reporting Information [Line Items]
Operating revenues	1,172		942	2,265	1,933
Income from operations	331		208	622	477
Tier 3 [Member]
Segment Reporting Information [Line Items]
Operating revenues	1,621		1,293	3,111	2,664
Income from operations	375		244	695	532
Other [Member]
Segment Reporting Information [Line Items]
Operating revenues	697		529	1,339	1,054
Income from operations	4		(10)	22	(35)
Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating revenues	5,435		4,322	10,406	8,852
Operating Segments [Member] \| Operating Group Total [Member]
Segment Reporting Information [Line Items]
Operating revenues	5,435		4,322	10,406	8,852
Operating Segments [Member] \| Solid Waste [Member]
Segment Reporting Information [Line Items]
Operating revenues	4,706		3,768	9,012	7,744
Operating Segments [Member] \| Tier 1 [Member]
Segment Reporting Information [Line Items]
Operating revenues	1,214		975	2,302	1,999
Operating Segments [Member] \| Tier 2 [Member]
Segment Reporting Information [Line Items]
Operating revenues	1,495		1,194	2,890	2,450
Operating Segments [Member] \| Tier 3 [Member]
Segment Reporting Information [Line Items]
Operating revenues	1,997		1,599	3,820	3,295
Operating Segments [Member] \| Other [Member]
Segment Reporting Information [Line Items]
Operating revenues	729		554	1,394	1,108
Intercompany Operating Revenues [Member]
Segment Reporting Information [Line Items]
Operating revenues	(959)		(761)	(1,818)	(1,562)
Intercompany Operating Revenues [Member] \| Operating Group Total [Member]
Segment Reporting Information [Line Items]
Operating revenues	(959)		(761)	(1,818)	(1,562)
Intercompany Operating Revenues [Member] \| Solid Waste [Member]
Segment Reporting Information [Line Items]
Operating revenues	(927)		(736)	(1,763)	(1,508)
Intercompany Operating Revenues [Member] \| Tier 1 [Member]
Segment Reporting Information [Line Items]
Operating revenues	(228)		(178)	(429)	(360)
Intercompany Operating Revenues [Member] \| Tier 2 [Member]
Segment Reporting Information [Line Items]
Operating revenues	(323)		(252)	(625)	(517)
Intercompany Operating Revenues [Member] \| Tier 3 [Member]
Segment Reporting Information [Line Items]
Operating revenues	(376)		(306)	(709)	(631)
Intercompany Operating Revenues [Member] \| Other [Member]
Segment Reporting Information [Line Items]
Operating revenues	(32)		(25)	(55)	(54)
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Income from operations	$ (269)		$ (185)	$ (555)	$ (432)