Certain Transfers of Financial Assets and Variable Interest Entities - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended			6 Months Ended
	Jun. 30, 2012		Jun. 30, 2011	Jun. 30, 2012		Jun. 30, 2011	Dec. 31, 2011
Total assets	$ 178,257			$ 178,257			$ 176,859
Loans Receivable Held-for-sale, Net	3,123	[1]		3,123	[1]		2,353	[1]
Total liabilities	157,689			157,689			156,793
Long-term Debt	13,076	[2]		13,076	[2]		10,908	[2]
Servicing fees received by the Company	70		72	151		144
Other assets	6,175			6,175			6,159
Senior financing outstanding to VIEs	6,327			6,327			6,279
Variable Interest Entity, Primary Beneficiary
Loans Receivable Held-for-sale, Net	322			322			315
Long-term Debt	700			700			722
Residential Mortgage | Variable Interest Entity, Not Primary Beneficiary [Member]
Loans and Leases Receivable, Gain (Loss) on Sales, Net	236		107	460		118
Transferor's Interests in Transferred Financial Assets, Fair Value	96			96			104
Total assets	484			484			529
Commercial and Corporate Loans [Member] | Variable Interest Entity, Not Primary Beneficiary [Member]
Total assets	1,900			1,900			2,000
Total liabilities	1,800			1,800			1,900
Commercial and Corporate Loans [Member] | Variable Interest Entity, Not Primary Beneficiary [Member] | Preference Shares
Total assets	2			2			2
Commercial and Corporate Loans [Member] | Variable Interest Entity, Primary Beneficiary
Loans Receivable, Net							315
Long-term Debt	288			288			289
Student Loans | Variable Interest Entity, Primary Beneficiary
Loans Receivable, Net	416			416			438
Long-term Debt	412			412			433
Student Loans | Variable Interest Entity, Primary Beneficiary | Upper Limit
Government guaranteed percent	97.00%			97.00%			97.00%
Collateralized Debt Obligations [Member] | Variable Interest Entity, Not Primary Beneficiary [Member]
Total assets	1,200			1,200			1,200
Declines in fair values for the total retained interests due to 20% adverse changes in the discount rate	28			28
Collateralized Debt Obligations [Member] | Variable Interest Entity, Not Primary Beneficiary [Member] | Trading Assets [Member]
Transferor's Interests in Transferred Financial Assets, Fair Value	43			43			43
Collateralized Debt Obligations [Member] | Variable Interest Entity, Not Primary Beneficiary [Member] | Lower Limit
Declines in fair values for the total retained interests due to 20% adverse changes in the discount rate	9			9
Total Return Swap | Variable Interest Entity, Not Primary Beneficiary [Member]
Senior financing outstanding to VIEs	1,900			1,900			1,700
VIEs had entered into TRS contracts with the Company with outstanding notional amounts	1,900			1,900			1,600
Derivative asset positions	29			29			20
Derivative Liability, Fair Value, Gross Liability	25			25			17
Community Development Investments [Member] | General Partner [Member]
Total assets	5			5			5
Total liabilities	1			1			1
Community Development Investments [Member] | Partnership [Member]
Total assets	349			349			360
Total liabilities	104			104			107
Community Development Investments [Member] | Variable Interest Entity, Not Primary Beneficiary [Member]
Total assets	1,200			1,200			1,200
Other assets	67			67			68
Community Development Investments [Member] | Variable Interest Entity, Not Primary Beneficiary [Member] | Limited Partner
Other assets	189			189			194
Loans issued by the Company to the limited partnerships	238			238			249
Ridgeworth Fund | Variable Interest Entity, Not Primary Beneficiary [Member]
Total assets	$ 1,000			$ 1,000			$ 1,100

[1] Includes loans held for sale, at fair value, of consolidated VIEs322 315

[2] Includes debt of consolidated VIEs ($288 and $289 at fair value as of June 30, 2012 and December 31, 2011, respectively)700 722