Derivatives (Net Gains (Losses) Recorded in the Consolidated Statements of Income Relating to Free-Standing Derivative Instruments Used for Risk Management and Other Business Purposes) (Detail) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016		Dec. 31, 2015
Derivative Instruments, Gain (Loss)
Net gains (losses) recorded in earnings	[1]	$ 2	$ 24		$ 90
Interest Rate Contract | Forward Contracts | Loans Held-for-Sale | Mortgage Banking Revenue
Derivative Instruments, Gain (Loss)
Net gains (losses) recorded in earnings		(17)	14		8
Interest Rate Contract | Mortgage Servicing Rights | Mortgage Banking Revenue | Residential Mortgage
Derivative Instruments, Gain (Loss)
Net gains (losses) recorded in earnings		2	24		90
Foreign Exchange Contract | Forward Contracts | Other Noninterest Income
Derivative Instruments, Gain (Loss)
Net gains (losses) recorded in earnings		(7)	2		23
Equity Contract | Warrant | Other Noninterest Income
Derivative Instruments, Gain (Loss)
Net gains (losses) recorded in earnings		0	73	[2]	325	[2]
Equity Contract | Swap | Other Noninterest Income
Derivative Instruments, Gain (Loss)
Net gains (losses) recorded in earnings		$ (80)	$ (56)		$ (37)

[1] Included in mortgage banking net revenue in the Consolidated Statements of Income.

[2] a) The Bancorp recognized a net gain of $ 9 on the exercise of the remaining warrant during the fourth quarter of 2016 and a net gain of $89 on both the sale and partial exercise of the warrant during the fourth quarter of 2015