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Schedule of Temporary Impairment Losses, Investments (Details) - USD ($) $ in Thousands | Mar. 31, 2021 | Dec. 31, 2020
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Schedule of Unrealized Losses and Estimated Fair Values [Line Items] |  |
Investment Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 616,229 | $ 3,755
Investment Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (13,689) | (10)
Investment Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | 0 | 0
Investment Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 0 | 0
Investment Securities, Continuous Unrealized Loss Position, Fair Value, Total | 616,229 | 3,755
Investment Securities, Continuous Unrealized Loss Position, Accumulated Loss | (13,689) | (10)
US Government Agencies Debt Securities Commercial |  |
Schedule of Unrealized Losses and Estimated Fair Values [Line Items] |  |
Investment Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | 91,266 |
Investment Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (1,098) |
Investment Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | 0 |
Investment Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 0 |
Investment Securities, Continuous Unrealized Loss Position, Fair Value, Total | 91,266 |
Investment Securities, Continuous Unrealized Loss Position, Accumulated Loss | (1,098) |
Residential Mortgage Backed Securities [Member] |  |
Schedule of Unrealized Losses and Estimated Fair Values [Line Items] |  |
Investment Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | 481,498 | 3,755
Investment Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (10,788) | (10)
Investment Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | 0 | 0
Investment Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 0 | 0
Investment Securities, Continuous Unrealized Loss Position, Fair Value, Total | 481,498 | 3,755
Investment Securities, Continuous Unrealized Loss Position, Accumulated Loss | (10,788) | $ (10)
US Government-sponsored Enterprises Debt Securities [Member] |  |
Schedule of Unrealized Losses and Estimated Fair Values [Line Items] |  |
Investment Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | 21,421 |
Investment Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (1,250) |
Investment Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | 0 |
Investment Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 0 |
Investment Securities, Continuous Unrealized Loss Position, Fair Value, Total | 21,421 |
Investment Securities, Continuous Unrealized Loss Position, Accumulated Loss | (1,250) |
Obligations of States and Political Subdivisions [Member] |  |
Schedule of Unrealized Losses and Estimated Fair Values [Line Items] |  |
Investment Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | 16,919 |
Investment Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (478) |
Investment Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | 0 |
Investment Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 0 |
Investment Securities, Continuous Unrealized Loss Position, Fair Value, Total | 16,919 |
Investment Securities, Continuous Unrealized Loss Position, Accumulated Loss | (478) |
Corporate Debt Securities [Member] |  |
Schedule of Unrealized Losses and Estimated Fair Values [Line Items] |  |
Investment Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | 5,125 |
Investment Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (75) |
Investment Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | 0 |
Investment Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 0 |
Investment Securities, Continuous Unrealized Loss Position, Fair Value, Total | 5,125 |
Investment Securities, Continuous Unrealized Loss Position, Accumulated Loss | $ (75) |

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