Contingencies and Commitments - Loss Contingencies (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Environmental [Member]
Environmental Contingencies
Liability recorded for projected environmental remediation costs	$ 8
Litigation Contingencies
Minimum potential loss related to environmental matters	8
Maximum potential loss related to environmental matters	46
Litigation [Member]
Litigation Contingencies
Minimum potential loss related to environmental matters	889
Maximum potential loss related to environmental matters	1,400
Aggregate reserves for claims deemed both probable and reasonably estimable	$ 260	$ 320

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 30

-Section 50

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- Definition

Amount of loss contingency liability.

+ References

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The estimated maximum amount of possible loss from the contingency.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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The estimated minimum amount of possible loss from the contingency.

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