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Commitments and Letters of Credit - Notional Amount of Commitments and Letter of Credit Instruments (Detail) - USD ($) $ in Thousands | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Commitments to extend credit |  |
Loss Contingencies [Line Items] |  |
Financial instrument of credit risk | $ 1,733,820 | $ 1,643,187
Financial standby letters of credit |  |
Loss Contingencies [Line Items] |  |
Financial instrument of credit risk | 18,108 | 17,843
Performance standby letters of credit |  |
Loss Contingencies [Line Items] |  |
Financial instrument of credit risk | 26,630 | 26,497
Commercial letters of credit |  |
Loss Contingencies [Line Items] |  |
Financial instrument of credit risk | $ 1,301 | $ 1,672

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- Definition Notional amount of outstanding commitments and letters of credit. + References No definition available. + Details
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Balance Type: | credit
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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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- Details
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- Details
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- Details
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