| Loans - Activity for SBA Loans Held for Sale (Detail) - USD ($) $ in Thousands | 3 Months Ended | |
|---|---|---|
| Mar. 31, 2020 | Mar. 31, 2019 | |
| Financing Receivable, Reclassification From Portfolio Loans To Loans Held For Sale [Roll Forward] | ||
| Balance at beginning of period | $ 6,020 | $ 9,390 | 
| Originations | 12,197 | 13,223 | 
| Sales | (18,212) | (15,459) | 
| Principal paydowns and amortization | (5) | (14) | 
| Balance at end of period | 7,140 | |
| Real Estate | ||
| Financing Receivable, Reclassification From Portfolio Loans To Loans Held For Sale [Roll Forward] | ||
| Balance at beginning of period | 2,943 | 5,194 | 
| Originations | 6,494 | 9,064 | 
| Sales | (9,432) | (7,756) | 
| Principal paydowns and amortization | (5) | (2) | 
| Balance at end of period | 6,500 | |
| Commercial and Industrial | ||
| Financing Receivable, Reclassification From Portfolio Loans To Loans Held For Sale [Roll Forward] | ||
| Balance at beginning of period | 3,077 | 4,196 | 
| Originations | 5,703 | 4,159 | 
| Sales | $ (8,780) | (7,703) | 
| Principal paydowns and amortization | (12) | |
| Balance at end of period | $ 640 | |
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- Definition Financing Receivable, Reclassification From Portfolio Loans To Loans Held For Sale [Roll Forward] No definition available. 
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- Definition Principal payoffs and amortization. No definition available. 
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- Definition The face amount of loans that will be sold to other entities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition The amount of cash paid for the origination of mortgages that are held for sale. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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- Definition The cash inflow resulting from the sale of loans classified as held-for-sale, including proceeds from loans sold through mortgage securitization. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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