Reconciliation of the Beginning and Ending Amounts of the Bancorp's Unrecognized Tax Benefits (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued [Abstract]
Unrecognized tax benefits at January 1	$ 7	[1]	$ 18	[1]	$ 14
Gross increases for tax positions taken during prior period	2		1		6
Gross decreases for tax positions taken during prior period			(7)		(3)
Gross increases for tax positions taken during current period	2		1		2
Settlements with taxing authorities			(5)
Lapse of applicable statute of limitations			(1)		(1)
Unrecognized tax benefits at December 31	$ 11	[1]	$ 7	[1]	$ 18	[1]

[1] Amounts represent unrecognized tax benefits that if recognized would affect the annual effective tax rate.