Assets and Liabilities Measured at Fair Value on a Recurring Basis (Detail) (USD $) In Millions	Sep. 30, 2011		Dec. 31, 2010		Sep. 30, 2010
Assets:
Residential mortgage loans held for sale	$ 1,593		$ 1,892		$ 1,879
Residential mortgage loans	62	[1]	46	[1]	42	[1]
Derivative assets	2,600		2,074		2,542
Total assets	19,829		18,852		19,864
Liabilities:
Derivative liabilities	1,505		1,314		1,448
Short positions	8		2		7
Total liabilities	1,513		1,316		1,455
Available-for-sale Securities | US Treasury and Government | Fair Value, Inputs, Level 1
Assets:
Securities	202		230		311
Available-for-sale Securities | Fair Value, Inputs, Level 1
Assets:
Securities	693	[2]	410	[2]	664	[2]
Available-for-sale Securities | Fair Value, Inputs, Level 1 | Equity Securities, Other
Assets:
Securities	491	[2]	180	[2]	353	[2]
US Treasury and Government | Fair Value, Inputs, Level 1 | Trading Securities
Assets:
Securities			1
Fair Value, Inputs, Level 1
Assets:
Derivative assets	3		90		3
Total assets	838		548		710
Liabilities:
Derivative liabilities	59		14		32
Short positions	7		1		6
Total liabilities	66		15		38
Fair Value, Inputs, Level 1 | Trading Securities
Assets:
Securities	142		48		43
Fair Value, Inputs, Level 1 | Trading Securities | Equity Securities, Other
Assets:
Securities	142		47		43
Fair Value, Inputs, Level 1 | Interest Rate Contract
Assets:
Derivative assets	3		90		3
Liabilities:
Derivative liabilities	59		14		32
Available-for-sale Securities | US States and Political Subdivisions Debt Securities | Fair Value, Inputs, Level 2
Assets:
Securities	105		172		195
Available-for-sale Securities | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises | Fair Value, Inputs, Level 2
Assets:
Securities	11,017		10,973		11,347
Available-for-sale Securities | Other Debt Securities | Fair Value, Inputs, Level 2
Assets:
Securities	1,573		1,342		1,018
Available-for-sale Securities | Fair Value, Inputs, Level 2
Assets:
Securities	14,692	[2]	14,136	[2]	14,417	[2]
Available-for-sale Securities | Fair Value, Inputs, Level 2 | US Government Agencies Debt Securities
Assets:
Securities	1,990		1,645		1,851
Available-for-sale Securities | Fair Value, Inputs, Level 2 | Equity Securities, Other
Assets:
Securities	7	[2]	4	[2]	6	[2]
US States and Political Subdivisions Debt Securities | Fair Value, Inputs, Level 2 | Trading Securities
Assets:
Securities	11		20		50
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises | Fair Value, Inputs, Level 2 | Trading Securities
Assets:
Securities	20		8		15
Other Debt Securities | Fair Value, Inputs, Level 2 | Trading Securities
Assets:
Securities	15		115		133
Fair Value, Inputs, Level 2
Assets:
Residential mortgage loans held for sale	1,593		1,892		1,879
Derivative assets	2,455		1,890		2,423
Total assets	18,786		18,158		18,991
Liabilities:
Derivative liabilities	1,414		1,261		1,357
Short positions	1		1		1
Total liabilities	1,415		1,262		1,358
Fair Value, Inputs, Level 2 | Trading Securities
Assets:
Securities	46		240		272
Fair Value, Inputs, Level 2 | Trading Securities | Equity Securities, Other
Assets:
Securities			97		74
Fair Value, Inputs, Level 2 | Interest Rate Contract
Assets:
Derivative assets	1,872		1,448		2,045
Liabilities:
Derivative liabilities	862		846		1,011
Fair Value, Inputs, Level 2 | Foreign Exchange Contract
Assets:
Derivative assets	471		343		273
Liabilities:
Derivative liabilities	447		323		249
Fair Value, Inputs, Level 2 | Commodity Contract
Assets:
Derivative assets	112		99		105
Liabilities:
Derivative liabilities	105		92		97
US States and Political Subdivisions Debt Securities | Fair Value, Inputs, Level 3 | Trading Securities
Assets:
Securities	1		1		1
Other Debt Securities | Fair Value, Inputs, Level 3 | Trading Securities
Assets:
Securities			5		4
Fair Value, Inputs, Level 3
Assets:
Residential mortgage loans	62	[1]	46	[1]	42	[1]
Derivative assets	142		94		116
Total assets	205		146		163
Liabilities:
Derivative liabilities	32		39		59
Total liabilities	32		39		59
Fair Value, Inputs, Level 3 | Interest Rate Contract
Assets:
Derivative assets	39		13		39
Liabilities:
Derivative liabilities	2		11		2
Fair Value, Inputs, Level 3 | Equity Contract
Assets:
Derivative assets	103		81		77
Liabilities:
Derivative liabilities	30		28		57
Fair Value, Inputs, Level 3 | Trading Securities
Assets:
Securities	1		6		5
Available-for-sale Securities
Assets:
Securities	15,385	[2]	14,546	[2]	15,081	[2]
Available-for-sale Securities | US Treasury and Government
Assets:
Securities	202		230		311
Available-for-sale Securities | US Government Agencies Debt Securities
Assets:
Securities	1,990		1,645		1,851
Available-for-sale Securities | US States and Political Subdivisions Debt Securities
Assets:
Securities	105		172		195
Available-for-sale Securities | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises
Assets:
Securities	11,017		10,973		11,347
Available-for-sale Securities | Other Debt Securities
Assets:
Securities	1,573		1,342		1,018
Available-for-sale Securities | Equity Securities, Other
Assets:
Securities	498	[2]	184	[2]	359	[2]
US Treasury and Government | Trading Securities
Assets:
Securities			1
US States and Political Subdivisions Debt Securities | Trading Securities
Assets:
Securities	12		21		51
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises | Trading Securities
Assets:
Securities	20		8		15
Other Debt Securities | Trading Securities
Assets:
Securities	15		120		137
Trading Securities
Assets:
Securities	189		294		320
Trading Securities | Equity Securities, Other
Assets:
Securities	142		144		117
Interest Rate Contract
Assets:
Derivative assets	1,914		1,551		2,087
Liabilities:
Derivative liabilities	923		871		1,045
Foreign Exchange Contract
Assets:
Derivative assets	471		343		273
Liabilities:
Derivative liabilities	447		323		249
Equity Contract
Assets:
Derivative assets	103		81		77
Liabilities:
Derivative liabilities	30		28		57
Commodity Contract
Assets:
Derivative assets	112		99		105
Liabilities:
Derivative liabilities	$ 105		$ 92		$ 97

[1] Includes residential mortgage loans originated as held for sale and subsequently transferred to held for investment

[2] Excludes FHLB and FRB restricted stock totaling $497 and $345, respectively, at September 30, 2011, $524 and $344 at December 31, 2010, and $551 and $343, respectively, at September 30, 2010.