Carrying Value of Those Assets Measured at Fair Value on a Non-Recurring Basis (Detail) (USD $)	3 Months Ended		9 Months Ended																						3 Months Ended	9 Months Ended	12 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended																					3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended		12 Months Ended	3 Months Ended	9 Months Ended		3 Months Ended	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012 Loans Held-for-Sale Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Loans Held-for-Sale Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Loans Held For Investment [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Loans Held For Investment [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Other Real Estate Owned [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Other Real Estate Owned [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Fair Value, Inputs, Level 1 [Member] Loans Held-for-Sale Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 1 [Member] Loans Held-for-Sale Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Fair Value, Inputs, Level 1 [Member] Loans Held For Investment [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 1 [Member] Loans Held For Investment [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Fair Value, Inputs, Level 1 [Member] Other Real Estate Owned [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 1 [Member] Other Real Estate Owned [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Fair Value, Inputs, Level 1 [Member] Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 1 [Member] Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Fair Value, Inputs, Level 1 [Member] Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 1 [Member] Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Valuation Allowance [Member] Loans Held-for-Sale Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Valuation Allowance [Member] Loans Held-for-Sale Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Valuation Allowance [Member] Loans Held-for-Sale Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Valuation Allowance [Member] Loans Held For Investment [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Valuation Allowance [Member] Loans Held For Investment [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Valuation Allowance [Member] Loans Held For Investment [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Valuation Allowance [Member] Other Real Estate Owned [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Valuation Allowance [Member] Other Real Estate Owned [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Valuation Allowance [Member] Other Real Estate Owned [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Valuation Allowance [Member] Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Valuation Allowance [Member] Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Valuation Allowance [Member] Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Valuation Allowance [Member] Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Valuation Allowance [Member] Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Valuation Allowance [Member] Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Fair Value, Inputs, Level 3 [Member] Loans Held-for-Sale Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Loans Held-for-Sale Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Fair Value, Inputs, Level 3 [Member] Loans Held For Investment [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Loans Held For Investment [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Fair Value, Inputs, Level 3 [Member] Other Real Estate Owned [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Other Real Estate Owned [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Fair Value, Inputs, Level 3 [Member] Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Fair Value, Inputs, Level 3 [Member] Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Fair Value, Inputs, Level 2 [Member] Loans Held-for-Sale Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Loans Held-for-Sale Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Fair Value, Inputs, Level 2 [Member] Loans Held For Investment [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Loans Held For Investment [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Fair Value, Inputs, Level 2 [Member] Other Real Estate Owned [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Other Real Estate Owned [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Fair Value, Inputs, Level 2 [Member] Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Affordable Housing [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Fair Value, Inputs, Level 2 [Member] Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Other Assets [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Community Development Investments [Member]	Sep. 30, 2012 Community Development Investments [Member]	Sep. 30, 2012 Land [Member] Fair Value, Inputs, Level 3 [Member]	Sep. 30, 2012 Land [Member] Fair Value, Inputs, Level 3 [Member]	Sep. 30, 2012 Nonperforming Financing Receivable [Member] Residential Mortgage, Loans Held For Sale [Member]	Sep. 30, 2012 Nonperforming Financing Receivable [Member] Residential Mortgage, Loans Held For Sale [Member]	Sep. 30, 2011 Nonperforming Financing Receivable [Member] Residential Mortgage, Loans Held For Sale [Member]	Dec. 31, 2011 Nonperforming Financing Receivable [Member] Residential Mortgage, Loans Held For Sale [Member]	Sep. 30, 2012 Student Loans [Member]	Sep. 30, 2012 Student Loans [Member]	Sep. 30, 2012 Federally Guaranteed Residential Loans [Member]	Sep. 30, 2012 Commercial Real Estate	Sep. 30, 2012 Commercial Real Estate	Sep. 30, 2012 Upper Limit	Sep. 30, 2012 Lower Limit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure					$ 1,258,000,000	$ 212,000,000	$ 52,000,000	$ 72,000,000	$ 304,000,000	$ 479,000,000	$ 80,000,000	$ 324,000,000	$ 44,000,000	$ 45,000,000	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0																$ 801,000,000	$ 104,000,000	$ 52,000,000	$ 72,000,000	$ 62,000,000	$ 107,000,000	$ 80,000,000	$ 324,000,000	$ 24,000,000	$ 21,000,000	$ 457,000,000	$ 108,000,000	$ 0	$ 0	$ 242,000,000	$ 372,000,000	$ 0	$ 0	$ 20,000,000	$ 24,000,000
Real Estate Owned, Valuation Allowance																									0	0	0	0	0	(7,000,000)	(126,000,000)	(126,000,000)	(127,000,000)	0	0	0	(4,000,000)	(4,000,000)	(20,000,000)
Asset Impairment Charges																									(121,000,000)	(121,000,000)	0	0	0	0	7,000,000	(8,000,000)	(9,000,000)	(96,000,000)	(96,000,000)	(10,000,000)	(8,000,000)	(6,000,000)	(17,000,000)																							(7,000,000)	(7,000,000)
Other than Temporary Impairment Losses, Investments																																																																3,000,000
valuation losses on affordable housing properties																																																												(96,000,000)	(96,000,000)
Transfer Of Portfolio Loans And Leases To Held For Sale Net Of Impairment																																																													200,000,000			16,000,000	563,000,000	57,000,000		1,400,000,000	1,700,000,000	1,000,000,000	38,000,000	161,000,000
Loans held for investment sold	649,000,000	202,000,000	2,000,000,000	479,000,000																																																													366,000,000		34,000,000		300,000,000	500,000,000
Allowance for Loan and Lease Losses, Write-offs	$ (585,000,000)	$ (536,000,000)	$ (1,445,000,000)	$ (1,714,000,000)																																																													$ (171,000,000)	$ (10,000,000)			$ (15,000,000)	$ (77,000,000)		$ (57,000,000)
Probable forecasted sale of Coke																																																																									7 years	6 years 6 months