Goodwill and Other Intangible Assets (Intangible Assets Subject to Amortization) (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	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 26,724		$ 26,724		$ 26,061
Accumulated amortization	12,475		12,475		11,911
Net	14,249		14,249		14,150
Intangible Assets, Net (Excluding Goodwill)	14,357		14,357		14,310
Adjustments To Reflect Present Value Of Future Profits In Run Off Insurance Operations To Reflect Effects That Would Have Been Recognized Had Related Unrealized Investment Securities Holding Gains Loses Actually Been Realized	300		300		322
Increase (Decrease) in Intangible Assets, Current			663
Amortization expense	465	429	1,316	1,257
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	8,508		8,508		7,938
Accumulated amortization	2,575		2,575		2,312
Net	5,933		5,933		5,626
Patents And Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	6,894		6,894		6,602
Accumulated amortization	2,918		2,918		2,621
Net	3,976		3,976		3,981
Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	1,167		1,167		1,356
Accumulated amortization	243		243		295
Net	924		924		1,061
Computer Software, Intangible Asset [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	8,500		8,500		8,256
Accumulated amortization	5,301		5,301		5,252
Net	3,199		3,199		3,004
Leases, Acquired-in-Place [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	594		594		703
Accumulated amortization	444		444		498
Net	150		150		205
Present Value Of Future Profits [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	605		605		574
Accumulated amortization	605		605		574
Net	0		0		0
All Other [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	456		456		632
Accumulated amortization	389		389		359
Net	$ 67		$ 67		$ 273