Provision for Income Taxes Provision for Income Taxes (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Income Taxes Information [Line Items]
Exchange gain associated with hedging program	$ 607	$ 35
Tax credit carryforward/back, net	1,080
Tax effect of net carryforwards/backs, net of valuation allowances, not subject to expiration	921
Unremitted earnings of subsidiaries outside the U.S.	17,226
Minimum amount of net reductions to company's global unrecognized tax benefit	100
Maximum amount of net reductions to company's global unrecognized tax benefit	125
Expires After 2014 but before 2019 [Member]
Income Taxes Information [Line Items]
Tax credit carryforward/back, net	1
Expiration date of net carryforwards/backs	before the end of 2019
Expires After 2019 [Member]
Income Taxes Information [Line Items]
Tax credit carryforward/back, net	$ 158
Expiration date of net carryforwards/backs	after 2019