v2.4.0.8
Condensed Consolidating Financial Information (Details) (USD $)
In Millions, unless otherwise specified
 3 Months Ended 12 Months Ended
Dec. 31, 2013
Sep. 30, 2013
Jun. 30, 2013
Mar. 31, 2013
Dec. 31, 2012
Sep. 30, 2012
Jun. 30, 2012
Mar. 31, 2012
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Condensed Consolidating Financial Information                      
Operating revenues $ 2,332 $ 2,558 $ 2,397 $ 2,197 $ 2,326 $ 2,431 $ 2,329 $ 2,110 $ 9,484 $ 9,196 $ 8,027
Cost and expenses                 7,186 7,511 7,576
Loss on impairment                 (81) (140) (5,201)
Gain (loss) on disposal of assets, net                 7 36 (12)
Operating income (loss) 407 742 602 473 541 811 (142) 371 2,224 1,581 (4,762)
Other income (expense), net                      
Interest income (expense), net                 (532) (667) (577)
Other, net                 (28) (48) (99)
Total other income (expense), net                 (560) (715) (676)
Income (loss) from continuing operations before income tax expense                 1,664 866 (5,438)
Income tax expense                 258 50 324
Income (loss) from continuing operations 228 544 321 313 432 533 (303) 154 1,406 816 (5,762)
Gain (loss) from discontinued operations, net of tax                 1 (1,027) 85
Net income (loss) 231 544 303 329 457 (383) (303) 18 1,407 (211) (5,677)
Net income attributable to noncontrolling interest                   8 77
Net income (loss) attributable to controlling interest 233 546 307 321 456 (381) (304) 10 1,407 (219) (5,754)
Other comprehensive income (loss) before income taxes                 260 (1) (181)
Income taxes related to other comprehensive loss                 2 (7) 13
Other comprehensive income (loss), net of income taxes                 262 (8) (168)
Total comprehensive income (loss)                 1,669 (219) (5,845)
Total comprehensive income (loss) attributable to noncontrolling interest                 3 8 73
Total comprehensive income (loss) attributable to controlling interest                 1,666 (227) (5,918)
Reportable Entity | Parent Guarantor
                      
Condensed Consolidating Financial Information                      
Operating revenues                 18    
Cost and expenses                 47 54 44
Operating income (loss)                 (29) (54) (44)
Other income (expense), net                      
Interest income (expense), net                 (15) (12) (11)
Equity in earnings                 1,450 (153) (5,699)
Other, net                 1    
Total other income (expense), net                 1,436 (165) (5,710)
Income (loss) from continuing operations before income tax expense                 1,407 (219) (5,754)
Income (loss) from continuing operations                 1,407 (219) (5,754)
Net income (loss)                 1,407 (219) (5,754)
Net income (loss) attributable to controlling interest                 1,407 (219) (5,754)
Other comprehensive income (loss) before income taxes                 3 (5) (3)
Other comprehensive income (loss), net of income taxes                 3 (5) (3)
Total comprehensive income (loss)                 1,410 (224) (5,757)
Total comprehensive income (loss) attributable to controlling interest                 1,410 (224) (5,757)
Reportable Entity | Subsidiary Issuer
                      
Condensed Consolidating Financial Information                      
Operating revenues                   5  
Cost and expenses                 9 16 4
Operating income (loss)                 (9) (11) (4)
Other income (expense), net                      
Interest income (expense), net                 (538) (576) (510)
Equity in earnings                 2,112 402 (5,174)
Other, net                 (15) (4) 9
Total other income (expense), net                 1,559 (178) (5,675)
Income (loss) from continuing operations before income tax expense                 1,550 (189) (5,679)
Income (loss) from continuing operations                 1,550 (189) (5,679)
Gain (loss) from discontinued operations, net of tax                 (97)    
Net income (loss)                 1,453 (189) (5,679)
Net income (loss) attributable to controlling interest                 1,453 (189) (5,679)
Other comprehensive income (loss) before income taxes                 238 (31) (114)
Other comprehensive income (loss), net of income taxes                 238 (31) (114)
Total comprehensive income (loss)                 1,691 (220) (5,793)
Total comprehensive income (loss) attributable to controlling interest                 1,691 (220) (5,793)
Reportable Entity | Other Subsidiaries
                      
Condensed Consolidating Financial Information                      
Operating revenues                 9,468 9,213 8,045
Cost and expenses                 7,132 7,463 7,546
Loss on impairment                 (81) (140) (5,201)
Gain (loss) on disposal of assets, net                 7 36 (12)
Operating income (loss)                 2,262 1,646 (4,714)
Other income (expense), net                      
Interest income (expense), net                 21 (79) (56)
Other, net                 (14) (44) (108)
Total other income (expense), net                 7 (123) (164)
Income (loss) from continuing operations before income tax expense                 2,269 1,523 (4,878)
Income tax expense                 258 50 324
Income (loss) from continuing operations                 2,011 1,473 (5,202)
Gain (loss) from discontinued operations, net of tax                 98 (1,027) 85
Net income (loss)                 2,109 446 (5,117)
Net income attributable to noncontrolling interest                   8 77
Net income (loss) attributable to controlling interest                 2,109 438 (5,194)
Other comprehensive income (loss) before income taxes                 19 35 (64)
Income taxes related to other comprehensive loss                 2 (7) 13
Other comprehensive income (loss), net of income taxes                 21 28 (51)
Total comprehensive income (loss)                 2,130 474 (5,168)
Total comprehensive income (loss) attributable to noncontrolling interest                 3 8 73
Total comprehensive income (loss) attributable to controlling interest                 2,127 466 (5,241)
Consolidating adjustments
                      
Condensed Consolidating Financial Information                      
Operating revenues                 (2) (22) (18)
Cost and expenses                 (2) (22) (18)
Other income (expense), net                      
Equity in earnings                 (3,562) (249) 10,873
Total other income (expense), net                 (3,562) (249) 10,873
Income (loss) from continuing operations before income tax expense                 (3,562) (249) 10,873
Income (loss) from continuing operations                 (3,562) (249) 10,873
Net income (loss)                 (3,562) (249) 10,873
Net income (loss) attributable to controlling interest                 (3,562) (249) 10,873
Total comprehensive income (loss)                 (3,562) (249) 10,873
Total comprehensive income (loss) attributable to controlling interest                 $ (3,562) $ (249) $ 10,873