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Derivative Financial Instruments (Schedule of Weighted-Average Rates Paid and Received for Interest Rate Swaps Outstanding) (Detail)	Dec. 31, 2016
Weighted Average Interest Rate Paid [Member]
Weighted Average Discount Rate [Line Items]
Fair Value Hedge Loan Lease Interest Rate Swaps	2.40%
Weighted-Average Interest Rate Received [Member]
Weighted Average Discount Rate [Line Items]
Fair Value Hedge Loan Lease Interest Rate Swaps	0.71%
Financial Institution Counterparties [Member] | Weighted Average Interest Rate Paid [Member]
Weighted Average Discount Rate [Line Items]
Non-hedging interest rate swaps - financial institution counterparties	3.97%
Financial Institution Counterparties [Member] | Weighted-Average Interest Rate Received [Member]
Weighted Average Discount Rate [Line Items]
Non-hedging interest rate swaps - financial institution counterparties	2.39%
Customer Counterparties [Member] | Weighted Average Interest Rate Paid [Member]
Weighted Average Discount Rate [Line Items]
Non-hedging interest rate swaps - customer counterparties	2.39%
Customer Counterparties [Member] | Weighted-Average Interest Rate Received [Member]
Weighted Average Discount Rate [Line Items]
Non-hedging interest rate swaps - customer counterparties	3.97%

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- Definition

Fair Value Hedge Loan Lease Interest Rate Swaps

+ References

No definition available.

+ Details

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- Definition

Non-hedging interest rate swaps

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No definition available.

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- Definition

Non-hedging interest rate swaps (2)

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- Definition

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.

+ References

No definition available.

+ Details

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- Details

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