Amount recognized for the passage of time, typically for liabilities, that have been discounted to their net present values. Excludes accretion associated with asset retirement obligations.

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

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The Increase or Decrease in the accrual for environmental loss in the period from revisions in estimates to existing obligations. The amount does not relate to changes in the environmental accrual related to business acquisitions or divestitures, or to currency movements.

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The aggregate amount disbursed during the reporting period to settle environmental loss contingencies.

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The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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Amount of the Increase or Decrease in the amount of the asset retirement obligation during the current period for changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

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Asset Retirement Obligation Increase Decrease For Acquisitions Divestitures And Other Adjustments

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Landfill and Environmental Remediation Liabilities - Changes to Landfill and Environmental Remediation Liabilities (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended			12 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014 Landfill Liabilities [Member]	Dec. 31, 2013 Landfill Liabilities [Member]	Sep. 30, 2014 Environmental Remediation Liabilities [Member]	Dec. 31, 2013 Environmental Remediation Liabilities [Member]
Environmental Exit Cost [Line Items]
Beginning balance, landfill			$ 1,421	$ 1,338
Beginning balance, environmental remediation					227	253
Obligations incurred and capitalized			40	59
Obligations settled			(47)	(71)
Obligations settled					(14)	(20)
Interest accretion	(65)	(65)	65	87
Interest accretion					4	4
Revisions in estimates and interest rate assumptions			(11)	6
Revisions in estimates and interest rate assumptions					14	(6)
Acquisitions, divestitures and other adjustments			(39)	2
Acquisitions, divestitures and other adjustments						(4)
Ending balance, landfill			1,429	1,421
Ending balance, environmental remediation	$ 231				$ 231	$ 227