Commitments and Contingencies Commitments and Contingencies (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Recorded Third-Party Environmental Recoveries [Line Items]
Recorded Third-Party Environmental Recoveries, Noncurrent	$ 129
Recorded Third-Party Environmental Recoveries, Current	57
Recorded Third-Party Environmental Recoveries, Amount	$ 186	$ 193

Recorded amount of the individual components comprising the asset for third-party recoveries related to environmental remediation obligations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859

+ Details

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- Definition

Cumulative amount of the asset for third-party recoveries related to environmental remediation obligations that is recoverable within one year of the balance sheet date.

+ References

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Cumulative amount of the asset for third-party recoveries related to environmental remediation obligations that is recoverable after one year from the balance sheet date.

+ References

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