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Landfill and Environmental Remediation Liabilities - Changes (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Landfill and environmental remediation liabilities
Interest accretion	$ 103	$ 98	$ 95
Ending balance, environmental remediation	230
Advanced Disposal [Member]
Landfill and environmental remediation liabilities
Acquisitions, divestitures and other adjustments	261
Landfill [Member]
Landfill and environmental remediation liabilities
Beginning balance, landfill	1,855
Obligations incurred and capitalized	83
Obligations settled	(103)
Interest accretion	103
Revisions in estimates and interest rate assumptions	(27)
Acquisitions, divestitures and other adjustments	245
Ending balance, landfill	2,156	$ 1,855
Asset Retirement Obligation Revision Of Estimate Increase Decrease Related To Change In Inflation Rate	(104)
Asset retirement obligation, increase (decrease) related to landfill closure	$ 8
Inflation Rate	2.25%	2.50%	2.50%
Asset Retirement Obligation Revision Of Estimate Increase Decrease Related To Reduction Of Amortization Expenses	$ (26)
Asset Retirement Obligation Increase Decrease For Landfill Liability Partially Offset By Change In Timing, Cost And Estimates Of Remaining Airspace	69
Environmental Remediation Liabilities [Member]
Landfill and environmental remediation liabilities
Beginning balance, environmental remediation	240
Obligations settled	(23)
Interest accretion	2
Revisions in estimates and interest rate assumptions	11
Ending balance, environmental remediation	230	$ 240
Increase (decrease) operating expenses due to change in discount rate	$ 9
Risk-free discount rate of the obligations	1.00%	1.75%	2.75%
Environmental Remediation Liabilities [Member] | Advanced Disposal [Member]
Landfill and environmental remediation liabilities
Acquisitions, divestitures and other adjustments	$ (17)

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

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The amount of increase (decrease) due to landfill liability partially offset by change in timing, cost and estimates of remaining airspace.

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