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The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

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Fair Value Measurements (Fair Value Measurements - Additional Information) (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended			6 Months Ended		12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015	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	$ 34			$ 34
Change in the fair value of the interest rate lock commitments, due to decrease in current interest rates of 25 bp	10			10
Change in the fair value of the interest rate lock commitments, due to decrease in current interest rates of 50 bp	18			18
Change in the fair value of the interest rate lock commitments, due to increase in current interest rates of 25 bp	11			11
Change in the fair value of the interest rate lock commitments, due to increase in current interest rates of 50 bp	23			23
Change in fair value of interest rate lock commitments, due to 10% adverse changes in the assumed loan closing rates	3			3
Change in fair value of interest rate lock commitments, due to 20% adverse changes in the assumed loan closing rates	7			7
Change in fair value of interest rate lock commitments, due to 10% favorable changes in the assumed loan closing rates	3			3
Change in fair value of interest rate lock commitments, due to 20% favorable changes in the assumed loan closing rates	7			7
Portfolio loans to loans held for sale				27	$ 369
Existing loans held for sale, further adjusted	$ 852			852		$ 519
Residential loans transferred to the Bancorp's portfolio				16	139
Fair value changes included in earnings for instruments for which the fair value option was elected				$ 45	18
Incremental Unit Purchase Option	7.8			7.8
Vantiv Holding, LLC Warrant Exercise Price	$ 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	$ 20	$ 26		$ 25	26
Net impact related to fair value adjustments					1
Gain Loss On Sales Of Loans Net				(2)	5
Commercial Loans HFS transferred from portfolio in the current quarter
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net impact related to fair value adjustments	5	1		5	1
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		2			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	3	2		4	5
Nonrecurring Losses Included As Charge-Offs	$ 3	$ 3		5	$ 8
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