Segment and Related Information - Revenues mix (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Segment revenue
Operating revenues	$ 5,159	$ 4,892
Collection and Disposal [Member]
Segment revenue
Operating revenues	4,716	4,523
Collection and Disposal [Member] | Collection [Member]
Segment revenue
Operating revenues	3,615	3,475
Collection and Disposal [Member] | Commercial [Member]
Segment revenue
Operating revenues	1,316	1,251
Collection and Disposal [Member] | Industrial [Member]
Segment revenue
Operating revenues	747	756
Collection and Disposal [Member] | Residential [Member]
Segment revenue
Operating revenues	854	829
Collection and Disposal [Member] | Other Collection [Member]
Segment revenue
Operating revenues	698	639
Collection and Disposal [Member] | Landfill [Member]
Segment revenue
Operating revenues	792	759
Collection and Disposal [Member] | Transfer [Member]
Segment revenue
Operating revenues	309	289
Recycling Processing and Sales [Member]
Segment revenue
Operating revenues	368	294
WM Renewable Energy [Member]
Segment revenue
Operating revenues	69	69
Corporate and Other [Member]
Segment revenue
Operating revenues	6	6
Operating Segments [Member]
Segment revenue
Operating revenues	6,317	6,034
Operating Segments [Member] | Collection and Disposal [Member]
Segment revenue
Operating revenues	5,799	5,578
Operating Segments [Member] | Collection and Disposal [Member] | Collection [Member]
Segment revenue
Operating revenues	4,062	3,888
Operating Segments [Member] | Collection and Disposal [Member] | Commercial [Member]
Segment revenue
Operating revenues	1,501	1,412
Operating Segments [Member] | Collection and Disposal [Member] | Industrial [Member]
Segment revenue
Operating revenues	934	933
Operating Segments [Member] | Collection and Disposal [Member] | Residential [Member]
Segment revenue
Operating revenues	876	854
Operating Segments [Member] | Collection and Disposal [Member] | Other Collection [Member]
Segment revenue
Operating revenues	751	689
Operating Segments [Member] | Collection and Disposal [Member] | Landfill [Member]
Segment revenue
Operating revenues	1,177	1,150
Operating Segments [Member] | Collection and Disposal [Member] | Transfer [Member]
Segment revenue
Operating revenues	560	540
Operating Segments [Member] | Recycling Processing and Sales [Member]
Segment revenue
Operating revenues	436	374
Operating Segments [Member] | WM Renewable Energy [Member]
Segment revenue
Operating revenues	70	70
Operating Segments [Member] | Corporate and Other [Member]
Segment revenue
Operating revenues	12	12
Intercompany [Member]
Segment revenue
Operating revenues	(1,158)	(1,142)
Intercompany [Member] | Collection and Disposal [Member]
Segment revenue
Operating revenues	(1,083)	(1,055)
Intercompany [Member] | Collection and Disposal [Member] | Collection [Member]
Segment revenue
Operating revenues	(447)	(413)
Intercompany [Member] | Collection and Disposal [Member] | Commercial [Member]
Segment revenue
Operating revenues	(185)	(161)
Intercompany [Member] | Collection and Disposal [Member] | Industrial [Member]
Segment revenue
Operating revenues	(187)	(177)
Intercompany [Member] | Collection and Disposal [Member] | Residential [Member]
Segment revenue
Operating revenues	(22)	(25)
Intercompany [Member] | Collection and Disposal [Member] | Other Collection [Member]
Segment revenue
Operating revenues	(53)	(50)
Intercompany [Member] | Collection and Disposal [Member] | Landfill [Member]
Segment revenue
Operating revenues	(385)	(391)
Intercompany [Member] | Collection and Disposal [Member] | Transfer [Member]
Segment revenue
Operating revenues	(251)	(251)
Intercompany [Member] | Recycling Processing and Sales [Member]
Segment revenue
Operating revenues	(68)	(80)
Intercompany [Member] | WM Renewable Energy [Member]
Segment revenue
Operating revenues	(1)	(1)
Intercompany [Member] | Corporate and Other [Member]
Segment revenue
Operating revenues	$ (6)	$ (6)