Landfill and Environmental Remediation Liabilities - Changes (Detail) $ in Millions	9 Months Ended
Sep. 30, 2021 USD ($)
Landfill and environmental remediation liabilities
Ending balance, environmental remediation	$ 216
Landfill [Member]
Landfill and environmental remediation liabilities
Beginning balance, landfill	2,156
Obligations incurred and capitalized	88
Obligations settled	(72)
Interest accretion	80
Revisions in estimates and interest rate assumptions	27
Acquisitions, divestitures and other adjustments	11
Ending balance, landfill	2,290
Asset retirement obligation, increase (decrease) related to landfill closure	15
Landfill [Member] \| Advanced Disposal [Member]
Landfill and environmental remediation liabilities
Obligations incurred and capitalized	13
Environmental Remediation Liabilities [Member]
Landfill and environmental remediation liabilities
Beginning balance, environmental remediation	230
Obligations settled	(14)
Interest accretion	2
Revisions in estimates and interest rate assumptions	(2)
Ending balance, environmental remediation	$ 216

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

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