Income Taxes (Deferred Tax Assets and Liabilities) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
NOL and credit carryforwards	$ 2,873	$ 3,120
Taxes related to risk management activities and derivatives	61	60
Reorganization items and impairments	216	262
Foreign capital losses	16	18
Other differences	0us-gaap_DeferredTaxAssetsOther	104us-gaap_DeferredTaxAssetsOther
Deferred tax assets before valuation allowance	3,166us-gaap_DeferredTaxAssetsGross	3,564us-gaap_DeferredTaxAssetsGross
Valuation allowance	(1,836)	(2,246)
Total deferred tax assets	1,330us-gaap_DeferredTaxAssetsNet	1,318us-gaap_DeferredTaxAssetsNet
Deferred tax liabilities: property, plant and equipment	(1,305)	(1,310)
Deferred Tax Liabilities, Other	(21)us-gaap_DeferredTaxLiabilitiesOther	0us-gaap_DeferredTaxLiabilitiesOther
Deferred Tax Liabilities, Gross	(1,326)us-gaap_DeferredIncomeTaxLiabilities	(1,310)us-gaap_DeferredIncomeTaxLiabilities
Net deferred tax asset (liability)	4us-gaap_DeferredTaxAssetsLiabilitiesNet	8us-gaap_DeferredTaxAssetsLiabilitiesNet
Less: Current portion deferred tax asset (liability)	(14)	12
Less: Non-current deferred tax asset	19	7
Deferred income tax liability, net of current	$ (1)	$ (11)

Amount of deferred tax liability attributable to taxable temporary differences.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Deferred Tax Liability

-URI http://asc.fasb.org/extlink&oid=6510232

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 15

-Subparagraph b(2)

-Article 7