Borrowings - Summary of Financial Data Pertaining to Federal Home Loan Bank Advances (Detail) - USD ($) $ in Thousands |
12 Months Ended | ||
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Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Federal Home Loan Banks [Abstract] | |||
| Weighted-average interest rate at end of year | 1.41% | 0.55% | 0.27% |
| Weighted-average interest rate during the year | 0.90% | 0.45% | 0.20% |
| Average balance of FHLB advances | $ 119,041 | $ 196,708 | $ 38,110 |
| Maximum amount outstanding at any month-end | $ 330,000 | $ 320,000 | $ 180,000 |
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- Definition The calculated average balance outstanding for the year for all Federal Home Loan Bank advances as of the Balance Sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The calculated weighted average interest rate for Federal Home Loan Bank advances outstanding as of the Balance Sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The calculated weighted average interest rate for Federal Home Loan Bank advances for the period ended as of the Balance Sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The maximum balance outstanding at any month end during the period as of the Balance Sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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