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Fair Value Measurements - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Jun. 30, 2009
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net fair value of the interest rate lock commitments	$ 15
Change in the fair value of the interest rate lock commitments, due to decrease in current interest rates of 25 bp	6
Change in the fair value of the interest rate lock commitments, due to decrease in current interest rates of 50 bp	11
Change in the fair value of the interest rate lock commitments, due to increase in current interest rates of 25 bp	7
Change in the fair value of the interest rate lock commitments, due to increase in current interest rates of 50 bp	14
Change in fair value of interest rate lock commitments, due to 10% adverse changes in the assumed loan closing rates	2
Change in fair value of interest rate lock commitments, due to 20% adverse changes in the assumed loan closing rates	3
Change in fair value of interest rate lock commitments, due to 10% favorable changes in the assumed loan closing rates	2
Change in fair value of interest rate lock commitments, due to 20% favorable changes in the assumed loan closing rates	3
Portfolio loans to loans held for sale	487	$ 855	$ 641
Existing loans held for sale, further adjusted	519	561
Residential loans transferred to the Bancorp's portfolio	288	31	44
Fair value changes included in earnings for instruments for which the fair value option was elected	$ 17	26
Incremental Unit Purchase Option	7.8
Vantiv Holding, LLC Warrant Exercise Price	$ 15.98
Percentage of Vantiv Holding, LLC sold to Advent for cash and warrants				51.00%
Private Equity Fund Impairment	$ 1		$ 4
Commercial Loans Held For Sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Portfolio loans to loans held for sale	37	28
Existing loans held for sale, further adjusted	1	2
Net impact related to fair value adjustments	1	10
Gain Loss On Sales Of Loans Net	5
Residential Mortgagel Loans Held For Sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Portfolio loans to loans held for sale	233	720
Net impact related to fair value adjustments	2	87
Automobile Loans Held For Sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Portfolio loans to loans held for sale	5
Credit Card Held For Sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Portfolio loans to loans held for sale	102
Fair value adjustment	2
Other Real Estate Owned
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net impact related to fair value adjustments	10	14
Nonrecurring Losses Included As Charge-Offs	14	12
Vantiv Holding, LLC
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percentage of Vantiv Holding, LLC sold to Advent for cash and warrants				51.00%
Residential Portfolio Segment
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Residential loans transferred to the Bancorp's portfolio	55
Fair value adjustment	1
The fair value of loans	$ 2	$ 2