Reclassifications Out of Accumulated Other Comprehensive Income (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Provision for income taxes	$ (392)	$ (1,462)	$ (2,248)
Other insignificant items	(462)	(389)	(364)
Net Income (Loss) Attributable to Parent	3,046	1,753	1,582
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Amortization of actuarial loss	(30)	(47)
Net settlement loss	(99)	(45)
Income from operations before income taxes	(129)	(92)
Provision for income taxes	62	34
Other insignificant items	(1)	(1)
Net Income (Loss) Attributable to Parent	$ (68)	$ (59)