Reclassifications out of Accumulated Other Comprehensive Income Reclassifications out of Accumulated Other Comprehensive Income (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Provision for income taxes	$ 144		$ (200)
Other insignificant, net of tax	(107)		(103)
Total reclassifications	(276)		1,149
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amortization of actuarial loss	(7)		(6)
Net settlement loss	(17)		(63)
Net curtailment gain	5		0
Income before income taxes	(19)		(69)
Provision for income taxes	7		23
Total reclassifications	(12)		(46)
United States and Foreign Pension Plans Defined Benefit [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net settlement loss	(17)	[1]	(63)	[1]
Net curtailment gain	$ (1)	[2]	$ 0

[1] Settlements are recognized as they occur, once it is probable that lump sum payments from a plan for a given year will exceed the plan's total service and interest cost for that year.

[2] Related to the workforce reduction, which reduced the future expected years of service for employees participating in the pla