Impacts of Derivative Financial Instruments on the Consolidated Statements of Income/(Loss) and the Consolidated Statements of Shareholders' Equity (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016		Mar. 31, 2015
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	$ 154		$ 206
Other Trading [Member] | Other Trading [Member]
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	15		15
Gain (Loss) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments	(18)		56
Other Trading [Member] | Credit Risk Contract [Member] | Other Trading [Member]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	5		6
Other Trading [Member] | Equity Contract [Member] | Other Trading [Member]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	2		3
Other Trading [Member] | Other Contract [Member] | Other Trading [Member]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	1
Mortgage Servicing Income [Member] | Mortgage Servicing Rights [Member]
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	169		88
Mortgage Production Income [Member] | Loans Held For Sale [Member]
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	(62)		(43)
Mortgage Production Income [Member] | Other Contract [Member] | Loans [Member]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	45		81
Other Income [Member] | Loans [Member]
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	(2)
Other Income [Member] | Credit Risk Contract [Member] | Loans [Member]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	(1)
Cash Flow Hedging [Member] | Interest Income [Member] | Interest Rate Contract [Member] | Adjustable Rate Loans [Member]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	306		125
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	38	[1]	35	[2]
Fair Value Hedging | Interest Rate Contract [Member]
Derivative, Gain (Loss) on Derivative, Net	(2)	[3]	14	[4]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	3	[3]	(14)	[4]
Gain (Loss) on Fair Value Hedge Ineffectiveness, Net	1	[3]	0
Fair Value Hedging | Other Trading [Member] | Interest Rate Contract [Member] | Brokered Time Deposits [Member]
Derivative, Gain (Loss) on Derivative, Net	0		0
Gain (Loss) on Fair Value Hedges Recognized in Earnings	0		0
Gain (Loss) on Fair Value Hedge Ineffectiveness, Net	0		0
Fair Value Hedging | Other Trading [Member] | Interest Rate Contract [Member] | Fixed Income Interest Rate [Member]
Derivative, Gain (Loss) on Derivative, Net	(2)	[3]	14	[4]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	3	[3]	(14)	[4]
Gain (Loss) on Fair Value Hedge Ineffectiveness, Net	$ 1	[3]	$ 0

[1] During the three months ended March 31, 2016, the Company also reclassified $29 million of pre-tax gains from AOCI into net interest income. These gains related to hedging relationships that have been terminated or de-designated and are reclassified into earnings consistent with the pattern of net cash flows expected to be recognized.

[2] During the three months ended March 31, 2015, the Company also reclassified $19 million of pre-tax gains from AOCI into net interest income. These gains related to hedging relationships that have been terminated or de-designated and are reclassified into earnings consistent with the pattern of net cash flows expected to be recognized.

[3] Amounts are recognized in trading income in the Consolidated Statements of Income.

[4] Amounts are recognized in trading income in the Consolidated Statements of Income.