Landfill and Environmental Remediation Liabilities - Changes (Detail) $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($)
Landfill and environmental remediation liabilities
Ending balance, environmental remediation	$ 213
Landfill [Member]
Landfill and environmental remediation liabilities
Beginning balance, landfill	2,156
Obligations incurred and capitalized	117
Obligations settled	(101)
Interest accretion	108
Revisions in estimates and interest rate assumptions	33
Acquisitions, divestitures and other adjustments	13
Ending balance, landfill	2,326
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	(22)
Interest accretion	3
Revisions in estimates and interest rate assumptions	2
Ending balance, environmental remediation	$ 213

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

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