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Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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Value of loans held-for-sale transferred to loans held in the entity's portfolio in noncash transactions.

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Fair Value Measurements - Additional Information (Detail) (USD $) In Millions	3 Months Ended		9 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010	Sep. 30, 2011 Residential Mortgage Loans	Sep. 30, 2010 Residential Mortgage Loans	Dec. 31, 2010 Residential Mortgage Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net fair value of the interest rate lock commitments	$ 37		$ 37
Increases in the fair value of the interest rate lock commitments, due to decrease in current interest rates of 25 bp	22		22
Increases in the fair value of the interest rate lock commitments, due to decrease in current interest rates of 50 bp	40		40
Decreases in the fair value of the interest rate lock commitments, due to increase in current interest rates of 25 bp	28		28
Decreases in the fair value of the interest rate lock commitments, due to increase in current interest rates of 50 bp	59		59
Decrease in fair value of interest rate lock commitments, due to 10% adverse changes in the assumed loan closing rates	4		4
Decrease in fair value of interest rate lock commitments, due to 20% adverse changes in the assumed loan closing rates	8		8
Increase in fair value of interest rate lock commitments, due to 10% favorable changes in the assumed loan closing rates	4		4
Increase in fair value of interest rate lock commitments, due to 20% favorable changes in the assumed loan closing rates	8		8
Commercial loans transferred from the portfolio to loans held for sale			115	650
Existing loans held for sale, further adjusted	1,593	1,879	1,593	1,879	1,892	3
Residential loans transferred to the Bancorp's portfolio			17	18		24	152
Net impact related to fair value adjustments			17
Fair value changes included in earnings for instruments for which the fair value option was elected	24	84	64	112
The fair value of loans	$ 3		$ 4	$ 5			$ 4	$ 5