Landfill and Environmental Remediation Liabilities - Changes (Detail) $ in Millions	6 Months Ended
Jun. 30, 2025 USD ($)
Landfill and Environmental Remediation Liabilities
Ending balance, environmental remediation	$ 217
Landfill [Member]
Landfill and Environmental Remediation Liabilities
Beginning balance, landfill	3,057
Obligations incurred and capitalized	42
Obligations settled	(73)
Interest accretion	71
Acquisitions, divestitures and other adjustments	7
Ending balance, landfill	3,104
Environmental Remediation Liabilities [Member]
Landfill and Environmental Remediation Liabilities
Beginning balance, environmental remediation	222
Obligations settled	(10)
Revisions in estimates and interest rate assumptions	5
Ending balance, environmental remediation	$ 217

Total costs accrued as of the balance sheet date for environmental loss contingencies.

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