Segment and Related Information - Revenues mix (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Segment revenue
Operating revenues	$ 5,402	$ 5,119	$ 10,561	$ 10,011
Collection and Disposal [Member]
Segment revenue
Operating revenues	4,922	4,734	9,638	9,257
Collection and Disposal [Member] | Collection [Member]
Segment revenue
Operating revenues	3,701	3,568	7,316	7,043
Collection and Disposal [Member] | Commercial [Member]
Segment revenue
Operating revenues	1,330	1,256	2,646	2,507
Collection and Disposal [Member] | Industrial [Member]
Segment revenue
Operating revenues	779	782	1,526	1,538
Collection and Disposal [Member] | Residential [Member]
Segment revenue
Operating revenues	863	841	1,717	1,670
Collection and Disposal [Member] | Other Collection [Member]
Segment revenue
Operating revenues	729	689	1,427	1,328
Collection and Disposal [Member] | Landfill [Member]
Segment revenue
Operating revenues	873	846	1,665	1,605
Collection and Disposal [Member] | Transfer [Member]
Segment revenue
Operating revenues	348	320	657	609
Recycling Processing and Sales [Member]
Segment revenue
Operating revenues	405	316	773	610
WM Renewable Energy [Member]
Segment revenue
Operating revenues	69	62	138	131
Corporate and Other [Member]
Segment revenue
Operating revenues	6	7	12	13
Operating Segments [Member]
Segment revenue
Operating revenues	6,637	6,328	12,954	12,362
Operating Segments [Member] | Collection and Disposal [Member]
Segment revenue
Operating revenues	6,080	5,857	11,879	11,435
Operating Segments [Member] | Collection and Disposal [Member] | Collection [Member]
Segment revenue
Operating revenues	4,171	4,009	8,233	7,897
Operating Segments [Member] | Collection and Disposal [Member] | Commercial [Member]
Segment revenue
Operating revenues	1,526	1,424	3,027	2,836
Operating Segments [Member] | Collection and Disposal [Member] | Industrial [Member]
Segment revenue
Operating revenues	978	974	1,912	1,907
Operating Segments [Member] | Collection and Disposal [Member] | Residential [Member]
Segment revenue
Operating revenues	886	866	1,762	1,720
Operating Segments [Member] | Collection and Disposal [Member] | Other Collection [Member]
Segment revenue
Operating revenues	781	745	1,532	1,434
Operating Segments [Member] | Collection and Disposal [Member] | Landfill [Member]
Segment revenue
Operating revenues	1,291	1,263	2,468	2,413
Operating Segments [Member] | Collection and Disposal [Member] | Transfer [Member]
Segment revenue
Operating revenues	618	585	1,178	1,125
Operating Segments [Member] | Recycling Processing and Sales [Member]
Segment revenue
Operating revenues	475	394	911	768
Operating Segments [Member] | WM Renewable Energy [Member]
Segment revenue
Operating revenues	70	63	140	133
Operating Segments [Member] | Corporate and Other [Member]
Segment revenue
Operating revenues	12	14	24	26
Intersegment Eliminations [Member]
Segment revenue
Operating revenues	(1,235)	(1,209)	(2,393)	(2,351)
Intersegment Eliminations [Member] | Collection and Disposal [Member]
Segment revenue
Operating revenues	(1,158)	(1,123)	(2,241)	(2,178)
Intersegment Eliminations [Member] | Collection and Disposal [Member] | Collection [Member]
Segment revenue
Operating revenues	(470)	(441)	(917)	(854)
Intersegment Eliminations [Member] | Collection and Disposal [Member] | Commercial [Member]
Segment revenue
Operating revenues	(196)	(168)	(381)	(329)
Intersegment Eliminations [Member] | Collection and Disposal [Member] | Industrial [Member]
Segment revenue
Operating revenues	(199)	(192)	(386)	(369)
Intersegment Eliminations [Member] | Collection and Disposal [Member] | Residential [Member]
Segment revenue
Operating revenues	(23)	(25)	(45)	(50)
Intersegment Eliminations [Member] | Collection and Disposal [Member] | Other Collection [Member]
Segment revenue
Operating revenues	(52)	(56)	(105)	(106)
Intersegment Eliminations [Member] | Collection and Disposal [Member] | Landfill [Member]
Segment revenue
Operating revenues	(418)	(417)	(803)	(808)
Intersegment Eliminations [Member] | Collection and Disposal [Member] | Transfer [Member]
Segment revenue
Operating revenues	(270)	(265)	(521)	(516)
Intersegment Eliminations [Member] | Recycling Processing and Sales [Member]
Segment revenue
Operating revenues	(70)	(78)	(138)	(158)
Intersegment Eliminations [Member] | WM Renewable Energy [Member]
Segment revenue
Operating revenues	(1)	(1)	(2)	(2)
Intersegment Eliminations [Member] | Corporate and Other [Member]
Segment revenue
Operating revenues	$ (6)	$ (7)	$ (12)	$ (13)