Acquisition and Discontinued Operations (Details 1) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012		Dec. 31, 2011		Jun. 30, 2011
Discontinued Assets and Liabilities of our Education Lending Business
Loans, net of unearned income of ($2), ($2) and $1	$ 49,605		$ 49,575		$ 47,840
Less: Allowance for loan and lease losses	888		1,004		1,230
Net loans	48,717		48,571		46,610
Trust accrued income and other assets at fair value	2,978	[1]	3,077	[1]	2,968	[1]
Total assets	5,533	[1]	5,860	[1]	6,328	[1]
Trust accrued expense and other liabilities at fair value	763		1,026		991
Total liabilities	2,401	[1]	2,550	[1]	2,950	[1]
Segment, Discontinued Operations [Member]
Discontinued Assets and Liabilities of our Education Lending Business
Loans, net of unearned income of ($2), ($2) and $1	2,830		3,010		3,161
Less: Allowance for loan and lease losses	79		104		109
Net loans	5,404		5,708		6,152
Accrued income and other assets	76		87		110
Total liabilities	2,401		2,550		2,950
Education Lending [Member]
Discontinued Assets and Liabilities of our Education Lending Business
Total assets	5,511		5,829		6,296
Total liabilities	2,401		2,550		2,949
Education Lending [Member] | Segment, Discontinued Operations [Member]
Discontinued Assets and Liabilities of our Education Lending Business
Loans, net of unearned income of ($2), ($2) and $1	2,830		3,010		3,161
Less: Allowance for loan and lease losses	79		104		109
Net loans	5,404		5,708		6,152
Accrued income and other assets	76		87		110
Trust [Member] | Segment, Discontinued Operations [Member]
Discontinued Assets and Liabilities of our Education Lending Business
Trust loans accounted for at fair value	2,580		2,726		3,100
Trust accrued income and other assets at fair value	31		34		34
Trust securities at fair value	2,373		2,522		2,919
Trust [Member] | Education Lending [Member] | Segment, Discontinued Operations [Member]
Discontinued Assets and Liabilities of our Education Lending Business
Trust loans accounted for at fair value	2,580		2,726		3,100
Trust accrued income and other assets at fair value	31		34		34
Trust accrued expense and other liabilities at fair value	28		28		30
Trust securities at fair value	2,373		2,522		2,919
Portfolio [Member] | Segment, Discontinued Operations [Member]
Discontinued Assets and Liabilities of our Education Lending Business
Trust loans accounted for at fair value	73		76
Portfolio [Member] | Education Lending [Member] | Segment, Discontinued Operations [Member]
Discontinued Assets and Liabilities of our Education Lending Business
Trust loans accounted for at fair value	$ 73		$ 76

[1] The assets of the VIEs can only be used by the particular VIE and there is no recourse to Key with respect to the liabilities of the consolidated LIHTC or education loan securitization trust VIEs.