Derivative Financial Instruments - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	6 Months Ended
Jun. 30, 2011	Dec. 31, 2010	Jun. 30, 2010
Derivative [Line Items]
Collateral from counterparties to offset changes in the fair value of derivative assets	$ 989	$ 903	$ 975
Valuation adjustments related to the credit risk associated with counterparties of customer accommodation derivative contracts	30	41	50
Collateral from counterparties to offset changes in the fair value of derivative liabilities	646	680	903
Maximum length of time over which the Bancorp is hedging its exposure to the variability in future cash flows related to the forecasted issuance of floating rate debt	21 months
Interest Rate Floor \| Cash Flow Hedging
Derivative [Line Items]
Deferred gains, net of tax, on cash flow hedges were recorded in accumulated other comprehensive income	68	67	85
Net deferred gains, net of tax, recorded in accumulated other comprehensive income are expected to be reclassified into earnings	35
Interest Rate Contract \| Lender Concentration Risk
Derivative [Line Items]
Notional amount of the risk participation agreements	723	851	824
Risk participation agreements had an average life (in years)	2.0
Interest Rate Contract \| Lender Concentration Risk \| Servicing Contracts
Derivative [Line Items]
Fair value of risk participation agreements	$ 2	$ 1	$ 1

Credit Risk Derivatives, Average Life

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Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

+ References

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- Definition

The amount as of the balance sheet date of the fair value of derivative assets that in accordance with the entity's accounting policy was not offset against an obligation to return cash collateral under a master netting arrangement.

+ References

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The amount as of the balance sheet date of the fair value of derivative liabilities that in accordance with the entity's accounting policy were offset against the right to reclaim cash collateral under a master netting arrangement.

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The net gain (loss) recognized in earnings in the period relating to components of the gain (loss) on credit risk hedging instruments excluded from the assessment of hedge effectiveness.

+ References

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- Definition

The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

+ References

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- Definition

Maximum length of time over which the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments.

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- Definition

Aggregate notional amount of all derivatives not designated as a hedging instrument. The notional amount relates to a number of currency units, shares, bushels, pounds, or other units specified in a derivative instrument.

+ References

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-Glossary Notional Amount
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Fair value of all derivative liabilities not designated as a hedging instrument.

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-Publisher FASB
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