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Exercise price per share or per unit of warrants or rights outstanding.

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Fair Value Measurements - Additional Information (Detail) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2015 USD ($) $ / shares shares	Mar. 31, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) $ / shares shares	Sep. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)	Jun. 30, 2015	Jun. 30, 2009
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Portfolio loans to loans held for sale				$ 470	$ 117
Existing loans held for sale, further adjusted	$ 617			617		$ 561
Residential loans transferred to the Bancorp's portfolio				274	24
Fair value changes included in earnings for instruments for which the fair value option was elected	$ 32		$ 23	$ 32	23
Incremental Unit Purchase Option \| shares	20			20
Vantiv Holding, LLC Warrant Exercise Price \| $ / shares	$ 15.98			$ 15.98
Percentage of Vantiv Holding, LLC sold to Advent for cash and warrants								51.00%
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	$ 26
Existing loans held for sale, further adjusted	1		1	$ 1	1
Gain Loss On Sales Of Loans Net				5	1
Commercial Loans HFS transferred from portfolio in the current quarter
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Portfolio loans to loans held for sale			8		10
Net impact related to fair value adjustments			4	1	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
Net impact related to fair value adjustments				1
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			102
Net impact related to fair value adjustments	1			1
Other Real Estate Owned
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net impact related to fair value adjustments	1			6	13
Nonrecurring Losses Included As Charge-Offs	2		$ 3	10	$ 9
Disposal Group Classified As Held For Sale [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Operating Branch Locations							105
Parcels Of Undeveloped Land							31
Residential Mortgage Loans
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
Interest Rate Lock Commitments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net fair value of the interest rate lock commitments	19			19
Change in the fair value of the interest rate lock commitments, due to decrease in current interest rates of 25 bp	7			7
Change in the fair value of the interest rate lock commitments, due to decrease in current interest rates of 50 bp	14			14
Change in the fair value of the interest rate lock commitments, due to increase in current interest rates of 25 bp	8			8
Change in the fair value of the interest rate lock commitments, due to increase in current interest rates of 50 bp	16			16
Change in fair value of interest rate lock commitments, due to 10% adverse changes in the assumed loan closing rates	2			2
Change in fair value of interest rate lock commitments, due to 20% adverse changes in the assumed loan closing rates	4			4
Change in fair value of interest rate lock commitments, due to 10% favorable changes in the assumed loan closing rates	2			2
Change in fair value of interest rate lock commitments, due to 20% favorable changes in the assumed loan closing rates	$ 4			$ 4