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Investments Securities (Gross Unrealized Losses and Fair Values of Securities) (Details) $ in Thousands | Dec. 31, 2020 USD ($) security | Dec. 31, 2019 USD ($) security
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Schedule of Investments [Line Items] |  |
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 118,172 | $ 34,430
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 459 | $ 134
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments | security | 14 | 6
Available-for-Sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | $ 13,260 | $ 70,605
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses | $ 5,284 | $ 4,266
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Investments | security | 9 | 16
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 2,973 | $ 2,722
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 38 | $ 6
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number Of Investments | security | 1 | 3
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | $ 9,486
Held-to-Maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses |  | $ 149
Held-to-Maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number Of Investments | security |  | 12
U.S. government agencies [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 39,611 | $ 24,907
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 322 | $ 80
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments | security | 7 | 3
Available-for-Sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | $ 14,987
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses |  | $ 13
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Investments | security |  | 3
Residential mortgage-backed agencies [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 22,899 | $ 4,900
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 100 | $ 17
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments | security | 2 | 1
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 2,973 | $ 2,722
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 38 | $ 6
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number Of Investments | security | 1 | 3
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | $ 9,486
Held-to-Maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses |  | $ 149
Held-to-Maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number Of Investments | security |  | 12
Commercial mortgage-backed agencies [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 16,034 | $ 4,623
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 36 | $ 37
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments | security | 1 | 2
Available-for-Sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | $ 5,793
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses |  | $ 55
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Investments | security |  | 3
Collateralized mortgage obligations [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 39,628 |
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses | $ 1 |
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments | security | 4 |
Available-for-Sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | $ 35,472
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses |  | $ 109
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, 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 | $ 13,260 | $ 14,353
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses | $ 5,284 | $ 4,089
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Investments | security | 9 | 9

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