Income Taxes (Details 3) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation of Effective Income Tax Rate
Statutory U.S. tax rate	35.00%	35.00%	35.00%
State income taxes--net of federal benefit	0.90%	0.90%	0.90%
International income taxes - net	(5.80%)	(6.30%)	(4.20%)
U.S. research and development credit	(0.40%)	(0.70%)	0.00%
Reserves for tax contingencies	0.60%	1.20%	(1.90%)
Domestic manufacturer's deduction	(1.30%)	(1.60%)	(1.20%)
All other--net	(0.10%)	(0.40%)	0.40%
Effective tax rate (as a percent)	28.90%	28.10%	29.00%
Federal, State and Foreign Tax
Gross UTB Balance at January 1	$ 659	$ 528	$ 594
Additions based on tax positions related to the current year	201	97	80
Additions for tax positions of prior years	30	158	114
Reductions for tax positions of prior years	(74)	(29)	(120)
Settlements (UTB decreases)	(154)	(17)	(50)
Reductions due to lapse of applicable statute of limitations	(79)	(78)	(90)
Gross UTB Balance at December 31	583	659	528
Income tax
Net UTB impacting the effective tax rate	265	262	185
Period discussed over which the Company is not able to reasonably estimate the amount by which the liability for unrecognized tax benefits could change as a result of ongoing income tax authority examinations	12 months
Interest and penalties related to unrecognized tax benefits, expense (benefit) recognized on a gross basis	(14)	22	(12)
Interest and penalties related to unrecognized tax benefits, accrued on a gross basis	44	62
Change in effective income tax rate from prior reporting period to current reporting period (as a percent)	0.80%	(0.90%)
Impact of factors that decreased the effective tax rate from prior reporting period to current reporting period (as a percent)	(0.80%)	(4.00%)
Impact of factors that increased the effective tax rate from prior reporting period to current reporting period (as a percent)	1.60%	3.10%
Amount of years inclusion of US R&D credit due to reinstatement in 2013		2 years
Deferred tax assets valuation allowance	22	23
Federal
Tax effected operating loss, capital loss, and tax credit carryovers
Tax effected operating loss, capital loss, and tax credit carryovers	24
Federal | Maximum
Tax effected operating loss, capital loss, and tax credit carryovers
Tax effected operating loss, capital loss, and tax credit carryovers, expiration date	16 years
Federal | Minimum
Tax effected operating loss, capital loss, and tax credit carryovers
Tax effected operating loss, capital loss, and tax credit carryovers, expiration date	15 years
State
Tax effected operating loss, capital loss, and tax credit carryovers
Tax effected operating loss, capital loss, and tax credit carryovers	3
State | Maximum
Tax effected operating loss, capital loss, and tax credit carryovers
Tax effected operating loss, capital loss, and tax credit carryovers, expiration date	10 years
State | Minimum
Tax effected operating loss, capital loss, and tax credit carryovers
Tax effected operating loss, capital loss, and tax credit carryovers, expiration date	5 years
International
Tax effected operating loss, capital loss, and tax credit carryovers
Tax effected operating loss, capital loss, and tax credit carryovers	$ 148
Tax effected operating loss, capital loss, and tax credit carryovers, expiration dates majority of high end of range	5 years
International | Minimum
Tax effected operating loss, capital loss, and tax credit carryovers
Tax effected operating loss, capital loss, and tax credit carryovers, expiration date	1 year