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Related Party Transactions - Additional Information (Detail) - Directors and Executive Officers [Member] $ in Thousands | 12 Months Ended
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Dec. 31, 2015 USD ($) SecurityLoan | Dec. 31, 2014 USD ($)
Related Party Transaction [Line Items] |  |
Granted loans to affiliate companies | $ 739 | $ 1,500
Subsequent advances | 8,700 |
Payment received | 9,100 |
Difference in related borrowings amounts | 440 |
Ownership interest amount | $ 26,300 | $ 26,100
Number of new loans approved | SecurityLoan | 1 |

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