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Securities (Details Textual) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract] |  |  |  |
Available-for-sale securities, gross realized gain (loss) | $ 41 | $ 0 |  |
Continuous unrealized loss position, fair value | $ 205,100 |  |  | $ 317,500
Continuous unrealized loss position, fair value (as a percent) | 30.00% |  | 53.00% |

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- Definition This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position in percentage. + References No definition available. + Details
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- Definition Securities, Continuous Unrealized Loss Position, Fair Value + References No definition available. + Details
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- Definition Amount of realized gain (loss) on 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/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27357-111563 + Details
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