Fair Value (Schedule of Fair Value Measurements, Liabilities, Using Significant Unobservable Inputs) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning balance, Liabilities	$ 19	$ 117	$ 26	$ 115
Recorded in Revenue, Liabilities	36	(17)	22	59
Recorded in Other Comprehensive Income, Liabilities	0	0	0	0
Purchases, Liabilities	0	0	0	0
Issuances, Liabilities	18	5	28	24
Sales, Liabilities	0	0	0	0
Settlements, Liabilities	(5)	(41)	(8)	(134)
Transfers in	0	0	0	0
Transfers out	0	0	0	0
Fair Value, ending balance, Liabilities	68	64	68	64
Change in Unrealized (Gains) Losses Related to Financial Instruments Held as of end of period	35	(15)	32	15
Derivative instruments, liabilities | Accrued expenses and other liabilities
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning balance, Liabilities	19	117	26	115
Recorded in Revenue, Liabilities	36	(17)	22	59
Recorded in Other Comprehensive Income, Liabilities	0	0	0	0
Purchases, Liabilities	0	0	0	0
Issuances, Liabilities	18	5	28	24
Sales, Liabilities	0	0	0	0
Settlements, Liabilities	(5)	(41)	(8)	(134)
Transfers in	0	0	0	0
Transfers out	0	0	0	0
Fair Value, ending balance, Liabilities	68	64	68	64
Change in Unrealized (Gains) Losses Related to Financial Instruments Held as of end of period	35	(15)	32	15
Foreign exchange contracts | Accrued expenses and other liabilities
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning balance, Liabilities	10	108	17	106
Recorded in Revenue, Liabilities	36	(17)	22	59
Recorded in Other Comprehensive Income, Liabilities	0	0	0	0
Purchases, Liabilities	0	0	0	0
Issuances, Liabilities	18	5	28	24
Sales, Liabilities	0	0	0	0
Settlements, Liabilities	(5)	(41)	(8)	(134)
Transfers in	0	0	0	0
Transfers out	0	0	0	0
Fair Value, ending balance, Liabilities	59	55	59	55
Change in Unrealized (Gains) Losses Related to Financial Instruments Held as of end of period	35	(15)	32	15
Other | Accrued expenses and other liabilities
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, beginning balance, Liabilities	9	9	9	9
Recorded in Revenue, Liabilities	0	0	0	0
Recorded in Other Comprehensive Income, Liabilities	0	0	0	0
Purchases, Liabilities	0	0	0	0
Issuances, Liabilities	0	0	0	0
Sales, Liabilities	0	0	0	0
Settlements, Liabilities	0	0	0	0
Transfers in	0	0	0	0
Transfers out	0	0	0	0
Fair Value, ending balance, Liabilities	9	9	9	9
Change in Unrealized (Gains) Losses Related to Financial Instruments Held as of end of period	$ 0	$ 0	$ 0	$ 0