Landfill and Environmental Remediation Liabilities - Changes to Landfill and Environmental Remediation Liabilities (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Environmental Exit Cost [Line Items]
Interest accretion	$ 22	$ 22
Ending balance, environmental remediation	243
Landfill [Member]
Environmental Exit Cost [Line Items]
Beginning balance, landfill	1,576
Obligations incurred and capitalized	15
Obligations settled	(14)
Interest accretion	22
Revisions in estimates and interest rate assumptions	8
Acquisitions, divestitures and other adjustments	1
Ending balance, landfill	1,608
Environmental Remediation Liabilities [Member]
Environmental Exit Cost [Line Items]
Beginning balance, environmental remediation	246
Obligations settled	(4)
Interest accretion	1
Revisions in estimates and interest rate assumptions	1
Acquisitions, divestitures and other adjustments	(1)
Ending balance, environmental remediation	$ 243

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

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