Shareowners' Equity (Changes In Accumulated Other Comprehensive Income) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012	Dec. 31, 2011
Stockholders Equity Note [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (758)	$ (1,592)	$ (940)
Other comprehensive income, net of tax	179	513
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	(3)	10
Securities Investment [Member]
Stockholders Equity Note [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	738	298	673	(33)
OCI before reclassifications	(56)	306
Reclassification from OCI	122	26
Reclassification from OCI net of deferred taxes	94	6
OCI before reclassifications net of deferred taxes	(34)	176
Other comprehensive income, net of tax	66	332
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	1	1
Currency Translation Adjustment [Member]
Stockholders Equity Note [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(119)	(274)	(131)	(399)
OCI before reclassifications	(9)	137
Reclassification from OCI	17	(3)
Reclassification from OCI net of deferred taxes	(33)	(5)
OCI before reclassifications net of deferred taxes	(191)	(45)
Other comprehensive income, net of tax	8	134
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	(4)	9
Cash Flow Hedge [Member]
Stockholders Equity Note [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(654)	(1,029)	(746)	(1,101)
OCI before reclassifications	(97)	514
Reclassification from OCI	189	(442)
Reclassification from OCI net of deferred taxes	(42)	(35)
OCI before reclassifications net of deferred taxes	56	27
Other comprehensive income, net of tax	92	72
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	0	0
Pension Plans, Defined Benefit [Member]
Stockholders Equity Note [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(723)	(587)	(736)	(563)
OCI before reclassifications	2	(31)
Reclassification from OCI net of deferred taxes	11	7
Other comprehensive income, net of tax	13	(24)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	0	0
Other Comprehensive Income (Loss), Amortization, Pension and Other Postretirement Benefit Plans, Net Prior Service Cost Recognized in Net Periodic Pension Cost, Tax	3	3
Other Comprehensive Income (Loss), Reclassification, Pension and Other Postretirement Benefit Plans, Net Gain (Loss) Recognized in Net Periodic Benefit Cost, Tax	$ 18	$ (13)