Certain Transfers of Financial Assets and Variable Interest Entities - Additional Information (Detail) (USD $)	3 Months Ended			9 Months Ended								3 Months Ended		9 Months Ended					12 Months Ended							9 Months Ended				9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended				3 Months Ended		9 Months Ended										3 Months Ended		9 Months Ended	12 Months Ended
	Sep. 30, 2011		Sep. 30, 2010	Sep. 30, 2011		Sep. 30, 2010	Jun. 30, 2011	Dec. 31, 2010		Jun. 30, 2010	Dec. 31, 2009	Sep. 30, 2011 Residential Mortgage Variable Interest Entity, Not Primary Beneficiary	Sep. 30, 2010 Residential Mortgage Variable Interest Entity, Not Primary Beneficiary	Sep. 30, 2011 Residential Mortgage Variable Interest Entity, Not Primary Beneficiary	Sep. 30, 2010 Residential Mortgage Variable Interest Entity, Not Primary Beneficiary	Dec. 31, 2010 Residential Mortgage Variable Interest Entity, Not Primary Beneficiary	Sep. 30, 2011 Residential Mortgage Variable Interest Entity, Not Primary Beneficiary Pricing Service	Sep. 30, 2011 Residential Mortgage Variable Interest Entity, Not Primary Beneficiary Subordinate Interests	Dec. 31, 2007 Commercial and Corporate Loans Variable Interest Entity, Not Primary Beneficiary	Sep. 30, 2011 Commercial and Corporate Loans Variable Interest Entity, Not Primary Beneficiary	Dec. 31, 2010 Commercial and Corporate Loans Variable Interest Entity, Not Primary Beneficiary	Sep. 30, 2011 Commercial and Corporate Loans Variable Interest Entity, Not Primary Beneficiary Preference Shares	Dec. 31, 2010 Commercial and Corporate Loans Variable Interest Entity, Not Primary Beneficiary Preference Shares	Sep. 30, 2011 Commercial and Corporate Loans Variable Interest Entity, Primary Beneficiary	Jan. 02, 2010 Commercial and Corporate Loans Variable Interest Entity, Primary Beneficiary	Sep. 30, 2011 Student Loans Variable Interest Entity, Primary Beneficiary	Dec. 31, 2010 Student Loans Variable Interest Entity, Primary Beneficiary	Sep. 30, 2010 Student Loans Variable Interest Entity, Primary Beneficiary	Sep. 30, 2011 Variable Interest Entity, Primary Beneficiary Upper Limit Student Loans	Sep. 30, 2011 Upper Limit Collateralized Debt Obligations Variable Interest Entity, Not Primary Beneficiary	Dec. 31, 2010 Upper Limit Collateralized Debt Obligations Variable Interest Entity, Not Primary Beneficiary	Sep. 30, 2011 Lower Limit Collateralized Debt Obligations Variable Interest Entity, Not Primary Beneficiary	Dec. 31, 2010 Lower Limit Collateralized Debt Obligations Variable Interest Entity, Not Primary Beneficiary	Sep. 30, 2011 Collateralized Debt Obligations Variable Interest Entity, Not Primary Beneficiary	Dec. 31, 2010 Collateralized Debt Obligations Variable Interest Entity, Not Primary Beneficiary	Sep. 30, 2011 Collateralized Debt Obligations Variable Interest Entity, Not Primary Beneficiary Trading Assets	Dec. 31, 2010 Collateralized Debt Obligations Variable Interest Entity, Not Primary Beneficiary Trading Assets	Sep. 30, 2011 Residential Mortgage Loan Securitization, Government Sponsored Enterprises	Sep. 30, 2010 Residential Mortgage Loan Securitization, Government Sponsored Enterprises	Sep. 30, 2011 Residential Mortgage Loan Securitization, Government Sponsored Enterprises	Sep. 30, 2010 Residential Mortgage Loan Securitization, Government Sponsored Enterprises	Sep. 30, 2011 Upper Limit Three Pillars Variable Interest Entity, Primary Beneficiary years	Sep. 30, 2011 Three Pillars Variable Interest Entity, Primary Beneficiary Commercial Portfolio Segment	Sep. 30, 2011 Lower Limit Three Pillars Variable Interest Entity, Primary Beneficiary years	Dec. 31, 2010 Variable Interest Entity, Primary Beneficiary Commercial Portfolio Segment Three Pillars	Sep. 30, 2011 Three Pillars Variable Interest Entity, Primary Beneficiary Trade Accounts Receivable [Member]	Sep. 30, 2011 Variable Interest Entity, Primary Beneficiary Loans Receivable [Member] Three Pillars	Dec. 31, 2010 Three Pillars Variable Interest Entity, Primary Beneficiary Loans Receivable [Member]	Dec. 31, 2010 Trade Accounts Receivable [Member] Three Pillars Variable Interest Entity, Primary Beneficiary	Sep. 30, 2011 Three Pillars Variable Interest Entity, Primary Beneficiary years	Sep. 30, 2010 Three Pillars Variable Interest Entity, Primary Beneficiary	Sep. 30, 2011 Three Pillars Variable Interest Entity, Primary Beneficiary years	Dec. 31, 2010 Three Pillars Variable Interest Entity, Primary Beneficiary years	Sep. 30, 2011 Three Pillars Variable Interest Entity, Primary Beneficiary Receivables	Dec. 31, 2010 Three Pillars Variable Interest Entity, Primary Beneficiary Receivables	Sep. 30, 2011 Total Return Swap Variable Interest Entity, Not Primary Beneficiary	Dec. 31, 2010 Total Return Swap Variable Interest Entity, Not Primary Beneficiary	Sep. 30, 2011 Community Development Investments Variable Interest Entity, Not Primary Beneficiary	Dec. 31, 2010 Community Development Investments Variable Interest Entity, Not Primary Beneficiary	Sep. 30, 2011 Community Development Investments Variable Interest Entity, Not Primary Beneficiary Limited Partner	Dec. 31, 2010 Community Development Investments Variable Interest Entity, Not Primary Beneficiary Limited Partner	Sep. 30, 2011 Community Development Investments General Partner	Dec. 31, 2010 Community Development Investments General Partner	Sep. 30, 2011 Community Development Investments Partnership [Member]	Dec. 31, 2010 Community Development Investments Partnership [Member]	Sep. 30, 2011 Ridgeworth Fund Variable Interest Entity, Not Primary Beneficiary	Dec. 31, 2010 Ridgeworth Fund Variable Interest Entity, Not Primary Beneficiary	Dec. 31, 2010 Variable Interest Entity, Not Primary Beneficiary	Sep. 30, 2011 Variable Interest Entity, Primary Beneficiary day		Dec. 31, 2010 Variable Interest Entity, Primary Beneficiary		Sep. 30, 2011 Commercial Portfolio Segment	Jun. 30, 2011 Commercial Portfolio Segment	Dec. 31, 2010 Commercial Portfolio Segment	Sep. 30, 2010 Commercial Portfolio Segment	Jun. 30, 2010 Commercial Portfolio Segment	Dec. 31, 2009 Commercial Portfolio Segment
Funding commitments extended by Three Pillars to its customers, almost all of which renew annually																																																		$ 4,100,000,000		$ 4,100,000,000	$ 4,100,000,000	$ 2,700,000,000	$ 2,400,000,000
Residential mortgage loans sold, pre-tax gains												167,000,000	220,000,000	285,000,000	443,000,000
Fair value of the residual interest												160,000,000		160,000,000		193,000,000	143,000,000	17,000,000																		42,000,000	29,000,000
Total assets	172,553,000,000			172,553,000,000				172,874,000,000				554,000,000		554,000,000		651,000,000				2,000,000,000	2,100,000,000	2,000,000	2,000,000		307,000,000			490,000,000						1,200,000,000	1,300,000,000								2,700,000,000		2,400,000,000													1,200,000,000	1,100,000,000			8,000,000	8,000,000	379,000,000	394,000,000	1,100,000,000	1,900,000,000
Total liabilities	152,353,000,000			152,353,000,000				149,744,000,000												1,900,000,000					279,000,000			490,000,000																																		1,000,000	1,000,000	110,000,000	123,000,000			2,000,000,000
Sale of corporate loans to multi-seller commercial paper conduits																			1,900,000,000
The Company completed a structured sale of corporate loans to multi-seller commercial paper conduits, which are VIEs administered by unrelated third parties, from which it retained a residual interest in the pool of loans transferred, percent																			3.00%
Loans held																								311,000,000		448,000,000	479,000,000
Debt issued	13,544,000,000	[1]		13,544,000,000	[1]			13,648,000,000	[1]															285,000,000		443,000,000	474,000,000																																										728,000,000	[1]	764,000,000	[1]
Recourse to the federal government																										To the extent that losses occur on the SPE’s assets, the SPE has recourse to the federal government as the guarantor up to a maximum guarantee amount of 97%.
Government guarantee																													97.00%
The weighted average remaining lives of the Company's retained interests, approximating (years)																																		23
Assumed discount rate in valuing securities, over LIBOR																														14.00%	16.00%	8.00%	14.00%
Declines in fair values for the total retained interests due to 20% adverse changes in the discount rate																														20,000,000		10,000,000		9,000,000	5,000,000
Servicing fees received by the Company	58,000,000		132,000,000	202,000,000		290,000,000																																87,000,000	94,000,000	263,000,000	280,000,000
Allowance for loan losses on consolidated loans	2,600,000,000		3,086,000,000	2,600,000,000		3,086,000,000	2,744,000,000	2,974,000,000		3,156,000,000	3,120,000,000																																1,700,000,000																														1,101,000,000	1,200,000,000	1,303,000,000	1,402,000,000	1,447,000,000	1,353,000,000
The Company's activities with Three Pillars generated total fee revenue for the Company, net of direct salary and administrative costs incurred by the Company																																																		18,000,000	20,000,000	50,000,000	50,000,000
Commercial paper issued																																																		58,000,000		58,000,000	99,000,000
Assets supporting those commitments have a weighted average life (years)																																																		3.0		3.0	2.3
Initial terms																																										3		1
The majority of the commitments that have been originated by companies operating across a number of industries which collateralize, percent of the outstanding commitments																																														40.00%	21.00%	14.00%	48.00%
Transactions structured to minimum implied credit and underwriting risk																																																		Each transaction added to Three Pillars is typically structured to a minimum implied A/A2 rating according to established credit and underwriting policies
Weighted average lives (days)																																																																					15
Minimum tangible net worth allowed for a period of 15 days																																																		5,000		5,000
Credit enhancement requirements as a percent of aggregate commitments of Three Pillars																																																		10.00%		10.00%
Other assets	6,595,000,000			6,595,000,000				7,814,000,000																																																				199,000,000	202,000,000
Maximum exposure to loss from variable interest entity																																																		4,200,000,000		4,200,000,000	4,200,000,000							446,000,000	458,000,000
Loans issued by the Company to the limited partnerships																																																												225,000,000	222,000,000
Senior financing outstanding to VIEs	6,288,000,000			6,288,000,000				6,175,000,000																																																1,400,000,000	972,000,000
VIEs had entered into TRS contracts with the Company with outstanding notional amounts																																																								1,400,000,000	969,000,000
Derivative asset positions																																																								47,000,000	34,000,000
Derivative liability positions																																																								$ 44,000,000	$ 32,000,000

[1] Includes debt of consolidated VIEs ($285 and $290 at fair value at September 30, 2011 and December 31, 2010, respectively) $728 $764