Fair Value Measurements (Details Textual) (USD $)	3 Months Ended
	Mar. 31, 2012		Dec. 31, 2011	Sep. 30, 2011	Mar. 31, 2011	Dec. 31, 2010
Fair Value Measurements (Textual) [Abstract]
Loans in Portfolio	$ 74,000,000
Commercial loan portfolios held-for-sale	25,000,000		15,000,000
Nonexit price methodology for valuing loan portfolio			0.20%
Loans, net of allowance	48,282,000,000		48,571,000,000		47,180,000,000
Loans held for sale	511,000,000		728,000,000	479,000,000	426,000,000	467,000,000
Notice Period to redeem quarterly investments (in days)	45 days
Transfer of commercial and consumer loans from held-for-sale to held-to-maturity, current fair value	23,000,000
Average maturity of short term financial instrument	less than six months
Fair Value Measurements (Additional Textual) [Abstract]
Period for evaluation of fair value of property	90 days
Passive funds [Member]
Fair Value Estimate Not Practicable (Textual) [Abstract]
Liquidation period of funds, minimum (in years)	1 year	[1]
Liquidation period of funds, maximum (in years)	7 years
Private equity funds [Member]
Fair Value Estimate Not Practicable (Textual) [Abstract]
Liquidation period of funds, minimum (in years)	1 year
Liquidation period of funds, maximum (in years)	10 years
Co-managed funds [Member]
Fair Value Estimate Not Practicable (Textual) [Abstract]
Maturity Period of funds, minimum (in Years)	3 years
Maturity Period of funds, maximum (in Years)	6 years
Segment, Discontinued Operations [Member]
Fair Value Measurements (Textual) [Abstract]
Loans, net of allowance	5,625,000,000		5,708,000,000		6,193,000,000
Loans held for sale					14,000,000
Segment, Discontinued Operations [Member] | Education Lending [Member]
Fair Value Measurements (Textual) [Abstract]
Loans in Portfolio	74,000,000		76,000,000
Loans, net of allowance	5,625,000,000		5,708,000,000		6,193,000,000
Loans held for sale	0		0		14,000,000
Residential Real Estate Mortgage Loans [Member]
Fair Value Measurements (Textual) [Abstract]
Loans, net of allowance	2,000,000,000		1,900,000,000
Carrying Amount [Member]
Fair Value Measurements (Textual) [Abstract]
Loans, net of allowance	48,282,000,000		48,571,000,000
Loans held for sale	511,000,000		728,000,000
Carrying Amount [Member] | Segment, Discontinued Operations [Member] | Education Lending [Member]
Fair Value Measurements (Textual) [Abstract]
Loans, net of allowance	2,800,000,000		2,900,000,000
Loans held for sale	0
Fair Value [Member]
Fair Value Measurements (Textual) [Abstract]
Loans, net of allowance	47,348,000,000		47,561,000,000
Loans held for sale	511,000,000		728,000,000
Fair Value [Member] | Segment, Discontinued Operations [Member] | Education Lending [Member]
Fair Value Measurements (Textual) [Abstract]
Loans in the trusts	2,700,000,000		2,700,000,000
Securities issued by the education lending securitization trust	2,500,000,000		2,500,000,000
Loans, net of allowance	2,400,000,000		2,500,000,000
Level 3 [Member]
Fair Value Measurements (Textual) [Abstract]
Commercial loan portfolios held-for-sale	$ 25,000,000		$ 15,000,000

[1] Assumes conversion of stock options and/or Preferred Series A, as applicable.