Landfill and Environmental Remediation Liabilities - Changes to Landfill and Environmental Remediation Liabilities (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Environmental Exit Cost [Line Items]
Interest accretion	$ (88)us-gaap_AccretionExpense	$ (87)us-gaap_AccretionExpense	$ (84)us-gaap_AccretionExpense
Ending balance, environmental remediation	235
Landfill [Member]
Environmental Exit Cost [Line Items]
Beginning balance, landfill	1,421	1,338
Obligations incurred and capitalized	54	59
Obligations settled	(69)	(71)
Interest accretion	88	87
Revisions in estimates and interest rate assumptions	(9)	6
Acquisitions, divestitures and other adjustments	(42)	2
Ending balance, landfill	1,443	1,421
Environmental Remediation Liabilities [Member]
Environmental Exit Cost [Line Items]
Beginning balance, environmental remediation	227	253
Obligations settled	(21)	(20)
Interest accretion	5	4
Revisions in estimates and interest rate assumptions	25	(6)
Acquisitions, divestitures and other adjustments	(1)	(4)
Ending balance, environmental remediation	$ 235	$ 227

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 amount added to the accrual for newly incurred environmental loss contingencies. These additions include remediation expense and interest accretion. These additions do not relate to changes in the environmental accrual related to a business acquisition or divestiture, to currency movements, or revisions in previously existing estimates.

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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 asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

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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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Accrual for environmental loss contingencies, increase (decrease) for acquisitions, divestitures and other adjustments, including foreign currency translation.

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Asset Retirement Obligation Increase Decrease For Acquisitions Divestitures And Other Adjustments

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