Consolidated Statements of Stockholders' Equity (USD $) In Millions, except Share data, unless otherwise specified	Total	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance at Dec. 31, 2011		$ 15	$ (492)	$ 16,349	$ (4,381)	$ (138)
Balance (Shares) at Dec. 31, 2011		1,531,006,390
Net income (loss)	(4,068)				(4,068)
Other comprehensive income (loss), net of tax
Foreign currency translation adjustment	32					32
Net change in unrealized gains and losses on derivative financial instruments, net of tax	82					82
Net change in unrealized costs associated with certain retirement plans	(9)					(9)
Impact of stock-based compensation plans, net of tax (Shares)		11,340,798
Impact of stock-based compensation plans, net of tax				80
Acquisition of treasury stock			(600)
Balance at Dec. 31, 2012		15	(1,092)	16,429	(8,449)	(33)
Balance (Shares) at Dec. 31, 2012		1,542,347,188
Net income (loss)	(121)				(121)
Other comprehensive income (loss), net of tax
Foreign currency translation adjustment	10					10
Net change in unrealized gains and losses on derivative financial instruments, net of tax	107					107
Net change in unrealized costs associated with certain retirement plans	22					22
Impact of stock-based compensation plans, net of tax (Shares)		17,955,446
Stock Issued During Period, Value, New Issues		1
Impact of stock-based compensation plans, net of tax				150
Acquisition of treasury stock			(500)
Balance at Dec. 31, 2013	6,539	16	(1,592)	16,579	(8,570)	106
Balance (Shares) at Dec. 31, 2013	1,560,302,634	1,560,302,634
Net income (loss)	(119)				(119)
Other comprehensive income (loss), net of tax
Foreign currency translation adjustment	(22)					(22)
Net change in unrealized gains and losses on derivative financial instruments, net of tax	78					78
Net change in unrealized costs associated with certain retirement plans	(18)					(18)
Impact of stock-based compensation plans, net of tax (Shares)		14,715,602
Stock Issued During Period, Value, New Issues		0
Impact of stock-based compensation plans, net of tax				124
Acquisition of treasury stock			(125)
Balance at Dec. 31, 2014	$ 6,457	$ 16	$ (1,717)	$ 16,703	$ (8,689)	$ 144
Balance (Shares) at Dec. 31, 2014	1,575,018,236	1,575,018,236