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Contingencies, Commitments and Guarantees (Details) (USD $)	9 Months Ended		12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Contingencies, Commitments and Guarantees (Textuals) [Abstract]
Number of years over which commitments will be invested in partnerships	5 years
Commitments to fund partnership investments	3,800,000,000		3,800,000,000
Liabilities for indemnities, guarantees and commitments	5,000,000		5,000,000
Additional liabilities for indemnities, guarantees and commitments	0
The approximate minimum amount of the aggregate range of reasonably possible losses in excess of amounts accrued for matters as to which an estimate can be made	0
The approximate maximum amount of the aggregate range of reasonably possible losses in excess of amounts accrued for matters as to which an estimate can be made	355,000,000
Asbestos Related Claims [Member]
Loss Contingencies
Asbestos-Related Claims	3,750	4,800	5,670
Superfund Site Settlement Agreements [Member]
Loss Contingencies
Number of regulatory matters and other claims	2
Payment request by Environmental Protection Agency	less than $1 million and an additional amount
Company estimate of aggregate costs to resolve Environmental Protection Agency matter	1,000,000
Roberts, et. Al. v. Tishman Speyer Properties, et. Al. [Member]
Loss Contingencies
Alleged damages by tenants	over $200 million
Unclaimed Property [Member]
Loss Contingencies
After tax charge to increase reserves in connection with identification of potential life insurance claims through database searches	117,000,000
Commitments to Extend Credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair Value Disclosure, Off-balance Sheet Risks, Amount, Liability	1,855,000,000		2,437,000,000
Interest Rate Lock Commitments [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair Value Disclosure, Off-balance Sheet Risks, Amount, Liability	6,300,000,000		2,500,000,000
Mortgage Loan Commitments [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair Value Disclosure, Off-balance Sheet Risks, Amount, Liability	3,743,000,000		3,754,000,000