Fair Values of Assets and Liabilities (Significant Unobservable Level 3 Inputs Recurring Basis) (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Fair Value Inputs [Line Items]
Derivative instruments		$ 2,126		$ 1,852
Residential mortgage loans
Fair Value Inputs [Line Items]
Residential mortgage loans measured at FV		160	$ 126
IRLCs, net
Fair Value Inputs [Line Items]
Derivative instruments		29	19
Stock warrants associated with Vantiv Holding, LLC
Fair Value Inputs [Line Items]
Derivative instruments		308	485
Swap associated with the sale of Visa, Inc. Class B shares
Fair Value Inputs [Line Items]
Derivative instruments		$ (55)	$ (60)
Minimum | Residential mortgage loans
Fair Value Inputs [Line Items]
Interest rate risk factor		(6.00%)	(5.70%)
Minimum | IRLCs, net
Fair Value Inputs [Line Items]
Loan closing rates		5.60%	2.30%
Minimum | Stock warrants associated with Vantiv Holding, LLC
Fair Value Inputs [Line Items]
Expected term (years)		2 years	2 years
Expected volatility	[1]	23.00%	22.90%
Minimum | Swap associated with the sale of Visa, Inc. Class B shares
Fair Value Inputs [Line Items]
Timing of the resolution of the covered litigation		Dec. 31, 2016	Sep. 30, 2016
Maximum | Residential mortgage loans
Fair Value Inputs [Line Items]
Interest rate risk factor		16.50%	18.30%
Credit risk factor		80.50%	47.90%
Maximum | IRLCs, net
Fair Value Inputs [Line Items]
Loan closing rates		94.00%	87.60%
Maximum | Stock warrants associated with Vantiv Holding, LLC
Fair Value Inputs [Line Items]
Expected term (years)		13 years 3 months 18 days	14 years 3 months 18 days
Expected volatility	[1]	30.40%	32.20%
Maximum | Swap associated with the sale of Visa, Inc. Class B shares
Fair Value Inputs [Line Items]
Timing of the resolution of the covered litigation		Mar. 31, 2021	Mar. 31, 2021
Weighted average | Residential mortgage loans
Fair Value Inputs [Line Items]
Interest rate risk factor		4.40%	5.30%
Credit risk factor		1.40%	1.20%
Weighted average | IRLCs, net
Fair Value Inputs [Line Items]
Loan closing rates		75.00%	67.00%
Weighted average | Stock warrants associated with Vantiv Holding, LLC
Fair Value Inputs [Line Items]
Expected term (years)		5 years 10 months 24 days	5 years 10 months 24 days
Expected volatility	[1]	25.90%	26.50%

[1] Based on historical and implied volatilities of Vantiv, Inc. and comparable companies assuming similar expected terms.