Securities - Realized Gains and Losses on Sales of Investment Securities (Detail) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Investments, Debt and Equity Securities [Abstract] | |||
| Gross realized gains on sales of investment securities | $ 1,891 | $ 396 | $ 6,776 |
| Gross realized losses on sales of investment securities | (143) | (350) | (165) |
| Net realized gains on sales of investment securities | 1,748 | 46 | 6,611 |
| Proceeds from sales of investment securities | $ 97,271 | $ 78,282 | $ 456,098 |
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- Definition This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition The cash inflow associated with the sale or maturity (principal being due) of securities not classified as either held-to-maturity securities or trading securities which are classified as available-for-sale securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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