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Investments (Gross Unrealized Losses and Fair Values of Securities) (Details) - USD ($) | Jun. 30, 2021 | Dec. 31, 2020
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Schedule of Investments [Line Items] |  |
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 155,868,000 | $ 118,172,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 4,518,000 | $ 459,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments | 19 | 14
Available-for-Sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | $ 16,230,000 | $ 13,260,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 2,349,000 | $ 5,284,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Investments | 9 | 9
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 8,268,000 | $ 2,973,000
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 327,000 | $ 38,000
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number Of Investments | 3 | 1
U.S. government agencies [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 34,409,000 | $ 39,611,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 1,949,000 | $ 322,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments | 6 | 7
Residential mortgage-backed agencies [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 31,481,000 | $ 22,899,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 545,000 | $ 100,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments | 3 | 2
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 8,268,000 | $ 2,973,000
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 327,000 | $ 38,000
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number Of Investments | 3 | 1
Commercial mortgage-backed agencies [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 24,748,000 | $ 16,034,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 477,000 | $ 36,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments | 3 | 1
Collateralized mortgage obligations [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 65,230,000 | $ 39,628,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 1,547,000 | $ 1,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments | 7 | 4
Collateralized debt obligations [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-Sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | $ 16,230,000 | $ 13,260,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 2,349,000 | $ 5,284,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Investments | 9 | 9

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