Segment and Related Information - Assets (Detail) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Segment Reporting
Total assets	$ 45,722	$ 44,567
Operating Segments [Member] | Collection and Disposal [Member]
Segment Reporting
Total assets	28,627	27,893
Operating Segments [Member] | East Tier [Member]
Segment Reporting
Total assets	15,875	15,328
Operating Segments [Member] | West Tier [Member]
Segment Reporting
Total assets	11,933	11,786
Operating Segments [Member] | Other Ancillary [Member]
Segment Reporting
Total assets	819	779
Operating Segments [Member] | Recycling Processing and Sales [Member]
Segment Reporting
Total assets	2,850	2,686
Operating Segments [Member] | WM Renewable Energy [Member]
Segment Reporting
Total assets	1,788	1,544
Operating Segments [Member] | WM Healthcare Solutions [Member]
Segment Reporting
Total assets	9,218	9,406
Operating Segments [Member] | Corporate and Other [Member]
Segment Reporting
Total assets	4,151	3,785
Intercompany Elimination [Member]
Segment Reporting
Total assets	$ (912)	$ (747)