Shareholders' Equity (Accumulated Other Comprehensive Income by Component) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
AOCI net of tax, beginning balance			$ (95)
Other comprehensive income (loss)	301	(774)	584	(883)
AOCI net of tax, ending balance	489		489
Accumulated Other Comprehensive Income (Loss)
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
AOCI net of tax, beginning balance			(95)	360
Other comprehensive income (loss) before reclassifications			574	(899)
Amounts reclassified out of AOCI			10	16
Other comprehensive income (loss)			584	(883)
AOCI net of tax, ending balance	489	(523)	489	(523)
Net Unrealized Gains (Losses) on Cash Flow Hedges
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
AOCI net of tax, beginning balance			161	69
Other comprehensive income (loss) before reclassifications			(62)	92
Amounts reclassified out of AOCI			1	2
Other comprehensive income (loss)			(61)	94
AOCI net of tax, ending balance	100	163	100	163
Net Unrealized Gains (Losses) on Available-for-Sale Securities
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
AOCI net of tax, beginning balance			(221)	519
Other comprehensive income (loss) before reclassifications			551	(694)
Amounts reclassified out of AOCI			(9)	1
Other comprehensive income (loss)			542	(693)
AOCI net of tax, ending balance	321	(174)	321	(174)
Net Unrealized Losses on Hedges of Net Investments in Non-U.S. Subsidiaries
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
AOCI net of tax, beginning balance			(14)	(14)
Other comprehensive income (loss) before reclassifications			0	0
Amounts reclassified out of AOCI			0	0
Other comprehensive income (loss)			0	0
AOCI net of tax, ending balance	(14)	(14)	(14)	(14)
Other-Than-Temporary Impairment on Held-to-Maturity Securities
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
AOCI net of tax, beginning balance			(47)	(65)
Other comprehensive income (loss) before reclassifications			11	9
Amounts reclassified out of AOCI			1	2
Other comprehensive income (loss)			12	11
AOCI net of tax, ending balance	(35)	(54)	(35)	(54)
Net Unrealized Losses on Retirement Plans
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
AOCI net of tax, beginning balance			(203)	(283)
Other comprehensive income (loss) before reclassifications			1	(2)
Amounts reclassified out of AOCI			17	10
Other comprehensive income (loss)			18	8
AOCI net of tax, ending balance	(185)	(275)	(185)	(275)
Foreign Currency Translation
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
AOCI net of tax, beginning balance			229	134
Other comprehensive income (loss) before reclassifications			73	(304)
Amounts reclassified out of AOCI			0	1
Other comprehensive income (loss)			73	(303)
AOCI net of tax, ending balance	$ 302	$ (169)	$ 302	$ (169)