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Investment in Securities (Narrative) (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($)
Investments, Debt and Equity Securities [Abstract] |  |  |
Number of securities that had an unrealized loss | 136 | 64 |
Number of securities that had an unrealized loss, greater than 12 months | 61 | 24 |
Percentage of total securities | 43.00% | 17.00% |
Premium related to purchase of state and political subdivisions | $ 6,857 | $ 7,147 |
Securities pledged as collateral | 0 | 3,750 |
Proceeds from sales of securities available-for-sale | 58,520 |  | $ 21,491
Gross realized gains | 180 | 0 | 387
Gross realized losses | $ 222 | $ 0 | $ 0

X
- Definition The percentage of the number of investment positions in the available-for-sale investments determined to be temporarily impaired. + References No definition available. + Details
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- Definition The premium related to the purchase of state and political subdivisions. + References No definition available. + Details
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- Definition Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details
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- Definition Number of investment positions in available-for-sale investments that have been in a continuous unrealized loss position for greater than or equal to a year for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement. + References No definition available. + Details
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- Definition Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 1A -Subparagraph (b)(1)(i) -URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729 + Details
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- Definition The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26853-111562 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (a),(b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585 + Details
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