Condensed Consolidating Financial Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Condensed Consolidating Financial Information
Operating revenues	$ 2,422	$ 2,242	$ 2,334	$ 2,144	$ 2,127	$ 2,281	$ 2,479	$ 2,579	$ 9,142	$ 9,466	$ 11,441
Cost and expenses									8,693	6,856	6,708
Loss on impairment					(1,000)				(5,229)	(1,010)	(334)
Gain on disposal of assets, net									4	257	(9)
Operating income (loss)	(5,807)	268	391	372	(668)	634	949	942	(4,776)	1,857	4,390
Other income (expense), net
Interest income (expense), net									(577)	(544)	(479)
Equity in earnings									18	8	6
Other, Net									(99)	(31)	2
Total other income (expense), net									(658)	(567)	(471)
Loss from continuing operations before income tax expense									(5,434)	1,290	3,919
Income tax expense									395	336	723
Loss from continuing operations	(6,102)	(53)	162	164	(804)	363	712	683	(5,829)	954	3,196
Income (loss) from discontinued operations, net of tax									197	34	(26)
Net income (loss)									(5,632)	988	3,170
Net income attributable to noncontrolling interest									93	27	(11)
Net income (loss) attributable to controlling interest	(6,119)	(71)	155	310	(799)	368	715	677	(5,725)	961	3,181
Five Year Revolving Credit Facility
Other income (expense), net
Term of revolving credit facility									5 years
Parent Guarantor
Condensed Consolidating Financial Information
Cost and expenses									44	45	26
Operating income (loss)									(44)	(45)	(26)
Other income (expense), net
Interest income (expense), net									(11)	1	1
Equity in earnings									(5,670)	1,005	3,206
Total other income (expense), net									(5,681)	1,006	3,207
Loss from continuing operations before income tax expense									(5,725)	961	3,181
Loss from continuing operations									(5,725)	961	3,181
Net income (loss)									(5,725)	961	3,181
Net income (loss) attributable to controlling interest									(5,725)	961	3,181
Subsidiary Issuer
Condensed Consolidating Financial Information
Cost and expenses									4	3	4
Operating income (loss)									(4)	(3)	(4)
Other income (expense), net
Interest income (expense), net									(510)	(494)	(521)
Equity in earnings									(5,145)	1,519	3,773
Other, Net									9	(7)	(43)
Total other income (expense), net									(5,646)	1,018	3,209
Loss from continuing operations before income tax expense									(5,650)	1,015	3,205
Loss from continuing operations									(5,650)	1,015	3,205
Net income (loss)									(5,650)	1,015	3,205
Net income (loss) attributable to controlling interest									(5,650)	1,015	3,205
Other Subsidiaries
Condensed Consolidating Financial Information
Operating revenues									9,160	9,481	11,455
Cost and expenses									8,663	6,823	6,692
Loss on impairment									(5,229)	(1,010)	(334)
Gain on disposal of assets, net									4	257	(9)
Operating income (loss)									(4,728)	1,905	4,420
Other income (expense), net
Interest income (expense), net									(56)	(51)	41
Equity in earnings									18	8	6
Other, Net									(108)	(24)	45
Total other income (expense), net									(146)	(67)	92
Loss from continuing operations before income tax expense									(4,874)	1,838	4,512
Income tax expense									395	336	723
Loss from continuing operations									(5,269)	1,502	3,789
Income (loss) from discontinued operations, net of tax									197	34	(26)
Net income (loss)									(5,072)	1,536	3,763
Net income attributable to noncontrolling interest									93	27	(11)
Net income (loss) attributable to controlling interest									(5,165)	1,509	3,774
Consolidating adjustments
Condensed Consolidating Financial Information
Operating revenues									(18)	(15)	(14)
Cost and expenses									(18)	(15)	(14)
Other income (expense), net
Equity in earnings									10,815	(2,524)	(6,979)
Total other income (expense), net									10,815	(2,524)	(6,979)
Loss from continuing operations before income tax expense									10,815	(2,524)	(6,979)
Loss from continuing operations									10,815	(2,524)	(6,979)
Net income (loss)									10,815	(2,524)	(6,979)
Net income (loss) attributable to controlling interest									$ 10,815	$ (2,524)	$ (6,979)