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Derivative Financial Instruments (Schedule of Amounts Related to Interest Rate Derivatives Included in Income Designated as Hedges of Cash Flows) (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Designated as Hedging Instrument [Member] | Interest Income on Loans [Member] | Interest Rate Swaps On Variable-Rate Loans [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount reclassified from accumulated other comprehensive income to interest | $ 0 | $ 0 | $ 30,604

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