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Investment Securities (Narrative) (Details) | 12 Months Ended
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Dec. 31, 2019 USD ($) Security | Dec. 31, 2018 USD ($) Security | Dec. 31, 2017 USD ($)
Investments [Abstract] |  |  |
Securities pledged as collateral | $ 676,900,000 | $ 751,000,000 |
Number of security positions, unrealized loss position | Security | 91 | 571 |
Number of security positions, unrealized loss position for more than 12 months | Security | 34 | 435 |
Securities, 12 months or longer, Fair Value | $ 47,202,000 | $ 672,797,000 |
Securities, 12 months or longer, Unrealized Losses | $ 659,000 | $ 18,467,000 |
Number of security positions, unrealized loss position for less than 12 months | Security | 57 | 136 |
Securities, less than 12 months, Fair Value | $ 178,723,000 | $ 50,770,000 |
Securities, less than 12 months, Unrealized Losses | 1,595,000 | 182,000 |
Impairment recorded | $ 0 | $ 0 | $ 0

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- Definition Amount of accumulated pre-tax unrealized loss on securities that have been in a loss position for twelve months or longer. + References No definition available. + Details
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- Definition Amount of accumulated pre-tax unrealized loss on investments in securities that have been in a loss position for less than twelve months. + References No definition available. + Details
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- Definition This item represents the fair value of securities that have been in a continuous unrealized loss position for twelve months or longer. + References No definition available. + Details
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- Definition Number of investments in securities measured at fair value with change in fair value and in unrealized loss position. + References No definition available. + Details
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- Definition Disclosure regarding factors used to determine that the impairment of securities not categorized as either held-to-maturity securities or trading securities (hence equal to available for sale securities) where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the available-for-sale investments determined to be temporarily impaired for less than twelve months. + References No definition available. + Details
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- Definition Disclosure regarding factors used to determine that the impairment of securities not categorized as either held-to-maturity securities or trading securities (hence equal to available for sale securities) where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the available-for-sale investments determined to be temporarily impaired for twelve months or longer. + References No definition available. + Details
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- References No definition available. + Details
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- Definition Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings and other comprehensive loss (OCI). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 8A -URI http://asc.fasb.org/extlink&oid=118954083&loc=SL6284422-111562 + Details
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