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Landfill and Environmental Remediation Liabilities - Changes (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Mar. 31, 2022	Sep. 30, 2022	Dec. 31, 2021
Landfill and environmental remediation liabilities
Ending balance, environmental remediation		$ 202
San Jacinto Waste Pits [Member]
Landfill and environmental remediation liabilities
Beginning balance, environmental remediation	$ 53	53
Revisions in estimates and interest rate assumptions	17	17
Ending balance, environmental remediation		68
Landfill [Member]
Landfill and environmental remediation liabilities
Beginning balance, landfill	2,326	2,326
Obligations incurred and capitalized		86
Obligations settled		(83)
Interest accretion		81
Revisions in estimates and interest rate assumptions		(15)
Acquisitions, divestitures and other adjustments		(8)
Ending balance, landfill		2,387
Environmental Remediation Liabilities [Member]
Landfill and environmental remediation liabilities
Beginning balance, environmental remediation	$ 213	213
Obligations settled		(18)
Interest accretion		3
Revisions in estimates and interest rate assumptions		4
Ending balance, environmental remediation		202
Increase (decrease) operating expenses due to change in discount rate		$ (16)
Risk-free discount rate applied to environmental remediation liabilities and recovery assets		3.75%	1.50%