Landfill and Environmental Remediation Liabilities - Changes (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Landfill and environmental remediation liabilities
Ending balance, environmental remediation	$ 216
San Jacinto Waste Pits [Member]
Landfill and environmental remediation liabilities
Beginning balance, environmental remediation	53
Revisions in estimates and interest rate assumptions	17
Ending balance, environmental remediation	70
Landfill [Member]
Landfill and environmental remediation liabilities
Beginning balance, landfill	2,326
Obligations incurred and capitalized	26
Obligations settled	(17)
Interest accretion	27
Revisions in estimates and interest rate assumptions	(13)
Acquisitions, divestitures and other adjustments	1
Ending balance, landfill	2,350
Environmental Remediation Liabilities [Member]
Landfill and environmental remediation liabilities
Beginning balance, environmental remediation	213
Obligations settled	(7)
Interest accretion	1
Revisions in estimates and interest rate assumptions	9
Ending balance, environmental remediation	216
Increase (decrease) operating expenses due to change in discount rate	$ (8)
Risk-free discount rate applied to environmental remediation liabilities and recovery assets	2.50%	1.50%

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

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