Business Segment Information - Consolidated Assets (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012		Dec. 31, 2011
Segment Reporting Information [Line Items]
Assets	$ 2,209,974	[1]	$ 2,129,046	[1]
Operating Segments [Member]
Segment Reporting Information [Line Items]
Assets	1,962,690		1,808,555
Asset And Liability Management Activities [Member]
Segment Reporting Information [Line Items]
Assets	622,722		611,793
Equity Investment Income [Member]
Segment Reporting Information [Line Items]
Assets	5,508		7,098
Liquidating Businesses [Member]
Segment Reporting Information [Line Items]
Assets	32,597		37,570
Intersegment Elimination [Member]
Segment Reporting Information [Line Items]
Assets	(554,426)		(492,251)
Other Adjustment [Member]
Segment Reporting Information [Line Items]
Assets	$ 140,883		$ 156,281

[1] Total assets include long-lived assets, which are primarily located in the U.S.