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Investments (Gross Unrealized Losses and Fair Values of Securities) (Details) $ in Thousands | Mar. 31, 2022 USD ($) security | Dec. 31, 2021 USD ($) security
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Schedule of Investments [Line Items] |  |
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 83,508 | $ 112,629
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 5,409 | $ 1,821
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments | security | 22 | 16
Available-for-Sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | $ 46,556 | $ 111,881
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 5,498 | $ 7,208
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Investments | security | 11 | 19
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 192,713 | $ 7,395
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 10,207 | $ 291
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number Of Investments | security | 52 | 6
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 7,791 | $ 2,782
Held-to-Maturity Securities, Continuous Unrealized Loss Position, More than 12 Months, Unrealized Losses | $ 984 | $ 145
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number Of Investments | security | 3 | 1
US Treasury Securities [Member] |  |
Schedule of Investments [Line Items] |  |
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 36,059 |
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 953 |
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number Of Investments | security | 4 |
U.S. government agencies [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 8,661 | $ 23,577
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 409 | $ 122
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments | security | 2 | 3
Available-for-Sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | $ 1,637 | $ 33,972
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 363 | $ 2,377
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Investments | security | 1 | 6
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 63,005 |
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 4,522 |
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number Of Investments | security | 9 |
Residential mortgage-backed agencies [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 27,175 | $ 29,507
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 2,023 | $ 257
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments | security | 3 | 3
Available-for-Sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | $ 17,123 | $ 19,154
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 1,998 | $ 712
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Investments | security | 2 | 2
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 14,874 | $ 7,395
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 340 | $ 291
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number Of Investments | security | 29 | 6
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 7,791 | $ 2,782
Held-to-Maturity Securities, Continuous Unrealized Loss Position, More than 12 Months, Unrealized Losses | $ 984 | $ 145
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number Of Investments | security | 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 | $ 27,640 | $ 32,177
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 1,819 | $ 787
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments | security | 7 | 4
Available-for-Sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | $ 8,593 | $ 5,211
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 855 | $ 214
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Investments | security | 2 | 1
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 20,641 |
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 1,171 |
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number Of Investments | security | 2 |
Collateralized mortgage obligations [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 17,359 | $ 24,322
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 1,157 | $ 649
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments | security | 9 | 5
Available-for-Sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | $ 8,637 | $ 43,076
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 840 | $ 2,376
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Investments | security | 1 | 5
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 55,523 |
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 2,967 |
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number Of Investments | security | 7 |
Obligations of states and political subdivisions [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 2,673 | $ 3,046
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 1 | $ 6
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments | security | 1 | 1
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 2,611 |
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 254 |
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number Of Investments | security | 1 |
Collateralized debt obligations [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-Sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | $ 10,566 | $ 10,468
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 1,442 | $ 1,529
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Investments | security | 5 | 5

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