Derivative Instruments - Impact on Statements of Income, Cash Flow Hedges (Details 6) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Gains/(losses) recorded in income and other comprehensive income/(loss)
Recognition of gain (loss) related to cash flow hedges in Income	$ (4.6)
Maximum length of time hedged in forecasted transactions	10 years
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Gains/(losses) recorded in income and other comprehensive income/(loss)
Total change in OCI for period	(424)	113	(251)
Cash Flow Hedging [Member]
Gains/(losses) recorded in income and other comprehensive income/(loss)
Hedge ineffectiveness recorded directly in income	0	5	19
Total income statement impact	(101)	33	320
Cash Flow Hedging [Member] | Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Gains/(losses) recorded in income and other comprehensive income/(loss)
Derivatives - effective portion reclassified from AOCI to income	(101)	28	301
Effective portion recorded in OCI	(525)	141	50
Total change in OCI for period	(424)	113	(251)
Cash Flow Hedging [Member] | Interest rate contract [Member]
Gains/(losses) recorded in income and other comprehensive income/(loss)
Derivatives - effective portion reclassified from AOCI to income	(108)	(3)	310
Hedge ineffectiveness recorded directly in income	0	5	19
Total income statement impact	(108)	2	329
Effective portion recorded in OCI	(565)	13	107
Total change in OCI for period	(457)	16	(203)
Cash Flow Hedging [Member] | Foreign exchange [Member]
Gains/(losses) recorded in income and other comprehensive income/(loss)
Derivatives - effective portion reclassified from AOCI to income	7	31	(9)
Hedge ineffectiveness recorded directly in income	0	0	0
Total income statement impact	7	31	(9)
Effective portion recorded in OCI	40	128	(57)
Total change in OCI for period	$ 33	$ 97	$ (48)