Segment and Related Information - Revenues mix (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Segment revenue
Operating revenues	$ 5,609	$ 5,198	$ 16,170	$ 15,209
Collection and Disposal [Member]
Segment revenue
Operating revenues	5,084	4,821	14,722	14,078
Collection and Disposal [Member] | Collection [Member]
Segment revenue
Operating revenues	3,796	3,643	11,112	10,686
Collection and Disposal [Member] | Commercial [Member]
Segment revenue
Operating revenues	1,359	1,285	4,005	3,792
Collection and Disposal [Member] | Industrial [Member]
Segment revenue
Operating revenues	797	788	2,323	2,326
Collection and Disposal [Member] | Residential [Member]
Segment revenue
Operating revenues	875	852	2,592	2,522
Collection and Disposal [Member] | Other Collection [Member]
Segment revenue
Operating revenues	765	718	2,192	2,046
Collection and Disposal [Member] | Landfill [Member]
Segment revenue
Operating revenues	923	847	2,588	2,452
Collection and Disposal [Member] | Transfer [Member]
Segment revenue
Operating revenues	365	331	1,022	940
Recycling Processing and Sales [Member]
Segment revenue
Operating revenues	432	305	1,205	915
WM Renewable Energy [Member]
Segment revenue
Operating revenues	87	67	225	198
Corporate and Other [Member]
Segment revenue
Operating revenues	6	5	18	18
Operating Segments [Member]
Segment revenue
Operating revenues	6,875	6,413	19,829	18,775
Operating Segments [Member] | Collection and Disposal [Member]
Segment revenue
Operating revenues	6,272	5,947	18,151	17,382
Operating Segments [Member] | Collection and Disposal [Member] | Collection [Member]
Segment revenue
Operating revenues	4,286	4,094	12,519	11,991
Operating Segments [Member] | Collection and Disposal [Member] | Commercial [Member]
Segment revenue
Operating revenues	1,564	1,464	4,591	4,300
Operating Segments [Member] | Collection and Disposal [Member] | Industrial [Member]
Segment revenue
Operating revenues	1,003	982	2,915	2,889
Operating Segments [Member] | Collection and Disposal [Member] | Residential [Member]
Segment revenue
Operating revenues	897	875	2,659	2,595
Operating Segments [Member] | Collection and Disposal [Member] | Other Collection [Member]
Segment revenue
Operating revenues	822	773	2,354	2,207
Operating Segments [Member] | Collection and Disposal [Member] | Landfill [Member]
Segment revenue
Operating revenues	1,345	1,259	3,813	3,672
Operating Segments [Member] | Collection and Disposal [Member] | Transfer [Member]
Segment revenue
Operating revenues	641	594	1,819	1,719
Operating Segments [Member] | Recycling Processing and Sales [Member]
Segment revenue
Operating revenues	503	386	1,414	1,154
Operating Segments [Member] | WM Renewable Energy [Member]
Segment revenue
Operating revenues	88	68	228	201
Operating Segments [Member] | Corporate and Other [Member]
Segment revenue
Operating revenues	12	12	36	38
Intersegment Eliminations [Member]
Segment revenue
Operating revenues	(1,266)	(1,215)	(3,659)	(3,566)
Intersegment Eliminations [Member] | Collection and Disposal [Member]
Segment revenue
Operating revenues	(1,188)	(1,126)	(3,429)	(3,304)
Intersegment Eliminations [Member] | Collection and Disposal [Member] | Collection [Member]
Segment revenue
Operating revenues	(490)	(451)	(1,407)	(1,305)
Intersegment Eliminations [Member] | Collection and Disposal [Member] | Commercial [Member]
Segment revenue
Operating revenues	(205)	(179)	(586)	(508)
Intersegment Eliminations [Member] | Collection and Disposal [Member] | Industrial [Member]
Segment revenue
Operating revenues	(206)	(194)	(592)	(563)
Intersegment Eliminations [Member] | Collection and Disposal [Member] | Residential [Member]
Segment revenue
Operating revenues	(22)	(23)	(67)	(73)
Intersegment Eliminations [Member] | Collection and Disposal [Member] | Other Collection [Member]
Segment revenue
Operating revenues	(57)	(55)	(162)	(161)
Intersegment Eliminations [Member] | Collection and Disposal [Member] | Landfill [Member]
Segment revenue
Operating revenues	(422)	(412)	(1,225)	(1,220)
Intersegment Eliminations [Member] | Collection and Disposal [Member] | Transfer [Member]
Segment revenue
Operating revenues	(276)	(263)	(797)	(779)
Intersegment Eliminations [Member] | Recycling Processing and Sales [Member]
Segment revenue
Operating revenues	(71)	(81)	(209)	(239)
Intersegment Eliminations [Member] | WM Renewable Energy [Member]
Segment revenue
Operating revenues	(1)	(1)	(3)	(3)
Intersegment Eliminations [Member] | Corporate and Other [Member]
Segment revenue
Operating revenues	$ (6)	$ (7)	$ (18)	$ (20)