Change in Fair Value of Financial Instruments for which the FVO has been Elected (Detail) (USD $) In Millions	3 Months Ended				9 Months Ended
	Sep. 30, 2011		Sep. 30, 2010		Sep. 30, 2011		Sep. 30, 2010
Trading Account Profits And Commissions [Member] | Loans Held-for-Sale
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	$ (11)		$ 7		$ (14)		$ 14
Trading Account Profits And Commissions [Member] | Trading Account Assets
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	3		1		15		(3)
Trading Account Profits And Commissions [Member] | Loans Held-for-Investment
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	(1)		1		3		(1)
Trading Account Profits And Commissions [Member] | Mortgage Servicing Rights [Member]
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	0		0		0		0
Trading Account Profits And Commissions [Member] | Brokered Deposits
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	27		(59)		24		(67)
Trading Account Profits And Commissions [Member] | Long-Term Debt
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	7		(97)		(31)		(222)
Mortgage Production Income [Member] | Loans Held-for-Sale
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	181	[1]	206	[1]	330	[1]	498	[1]
Mortgage Production Income [Member] | Trading Account Assets
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	0	[1]	0	[1]	0	[1]	0	[1]
Mortgage Production Income [Member] | Loans Held-for-Investment
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	17	[1]	6	[1]	13	[1]	13	[1]
Mortgage Production Income [Member] | Mortgage Servicing Rights [Member]
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	1	[1]	8	[1]	5	[1]	14	[1]
Mortgage Production Income [Member] | Brokered Deposits
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	0	[1]	0	[1]	0	[1]	0	[1]
Mortgage Production Income [Member] | Long-Term Debt
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	0	[1]	0	[1]	0	[1]	0	[1]
Mortgage Servicing Income [Member] | Loans Held-for-Sale
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	0		0		0		0
Mortgage Servicing Income [Member] | Trading Account Assets
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	0		0		0		0
Mortgage Servicing Income [Member] | Loans Held-for-Investment
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	0		0		0		0
Mortgage Servicing Income [Member] | Mortgage Servicing Rights [Member]
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	(437)		(290)		(582)		(810)
Mortgage Servicing Income [Member] | Brokered Deposits
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	0		0		0		0
Mortgage Servicing Income [Member] | Long-Term Debt
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	0		0		0		0
Trading Account Assets
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	3	[2]	1	[3]	15	[2]	(3)	[3]
Loans Held-for-Sale
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	170	[2]	213	[3]	316	[2]	512	[3]
Mortgage Servicing Rights [Member]
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	(436)	[2]	(282)	[3]	(577)	[2]	(796)	[3]
Brokered Deposits
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	27	[2]	(59)	[3]	24	[2]	(67)	[3]
Long-Term Debt
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	7	[2]	(97)	[3]	(31)	[2]	(222)	[3]
Loans Held-for-Investment
Fair Value Gain/(Loss) for Items Measured at Fair Value Pursuant to Election of the Fair Value Option	$ 16	[2]	$ 7	[3]	$ 16	[2]	$ 12	[3]

[1] For the three and nine months ended September 30, 2011, income related to LHFS includes $46 million and $178 million, respectively, related to MSRs recognized upon the sale of loans reported at fair value. For the three and nine months ended September 30, 2011, income related to MSRs includes $1 million and $5 million, respectively, of MSRs recognized upon the sale of loans reported at LOCOM. These MSRs are included in the table since the Company elected to report MSRs recognized in 2009 using the fair value method. Previously, MSRs were reported under the amortized cost method.

[2] Changes in fair value for the three and nine months ended September 30, 2011, exclude accrued interest for the periods then ended. Interest income or interest expense on trading assets, LHFS, LHFI, brokered deposits and long-term debt that have been elected to be carried at fair value are recorded in interest income or interest expense in the Consolidated Statements of Income based on their contractual coupons. Certain trading assets do not have a contractually stated coupon and, for these securities, the Company records interest income based on the effective yield calculated upon acquisition of the securities.

[3] Changes in fair value for the three and nine months ended September 30, 2010, exclude accrued interest for the periods then ended. Interest income or interest expense on trading assets, LHFS, LHFI, brokered deposits and long-term debt that have been elected to be carried at fair value are recorded in interest income or interest expense in the Consolidated Statements of Income based on their contractual coupons. Certain trading assets do not have a contractually stated coupon and, for these securities, the Company records interest income based on the effective yield calculated upon acquisition of the securities.