Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015
Net cash provided by (used in) operating activities included:
Interest paid (net of amounts capitalized)	$ (177)	$ (143)
Income taxes paid to taxing authorities	(61)	(165)
Noncash investing activities:
Asset retirement costs capitalized	2	6
Asset retirement obligations assumed by buyer	$ 83	$ 0

Asset Retirement Obligation, Liabilities Transferred

No definition available.

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- Definition

Noncash additions to PP&E for asset retirement costs capitalized, excluding acquisitions and discontinued operations.

+ References

No definition available.

+ Details

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- References

No definition available.

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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

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- Definition

The amount of cash paid for interest during the period net of cash paid for interest that is capitalized.

+ References

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- References

No definition available.

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