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Securities - Continuous Unrealized Loss Position (Details) - USD ($) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2020
Securities |  |  |  |  |
Proceeds from the sale of available for sale investments | $ 7,300,000 | $ 26,400,000 | $ 20,855,000 | $ 44,592,000 |
Gross gain on sale of available for sale investments | 314,000 | 1,300,000 | 562,000 | 1,500,000 |
Gross loss on sale of available for sale investments | 0 | $ 0 | 200,000 | $ 202,000,000 |
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value |  |  |  |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Less than 12 Months | 62,188,000 |  | 62,188,000 |  | $ 10,529,000
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, 12 Months or Longer | 1,007,000 |  | 1,007,000 |  | 7,443,000
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Total | 63,195,000 |  | 63,195,000 |  | 17,972,000
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses |  |  |  |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Less than 12 Months | (732,000) |  | (732,000) |  | (86,000)
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, 12 Months or Longer | (20,000) |  | (20,000) |  | (71,000)
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Total | (752,000) |  | (752,000) |  | (157,000)
U.S. asset backed securities |  |  |  |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value |  |  |  |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Less than 12 Months | 4,158,000 |  | 4,158,000 |  | 2,884,000
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, 12 Months or Longer |  |  |  |  | 7,443,000
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Total | 4,158,000 |  | 4,158,000 |  | 10,327,000
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses |  |  |  |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Less than 12 Months | (26,000) |  | (26,000) |  | (4,000)
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, 12 Months or Longer |  |  |  |  | (71,000)
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Total | (26,000) |  | (26,000) |  | (75,000)
U.S. government agency mortgage-backed securities |  |  |  |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value |  |  |  |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Less than 12 Months | 1,614,000 |  | 1,614,000 |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Total | 1,614,000 |  | 1,614,000 |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses |  |  |  |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Less than 12 Months | (29,000) |  | (29,000) |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Total | (29,000) |  | (29,000) |  |
U.S. government agency collateralized mortgage obligations |  |  |  |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value |  |  |  |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Less than 12 Months | 7,315,000 |  | 7,315,000 |  | 2,284,000
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Total | 7,315,000 |  | 7,315,000 |  | 2,284,000
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses |  |  |  |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Less than 12 Months | (142,000) |  | (142,000) |  | (17,000)
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Total | (142,000) |  | (142,000) |  | (17,000)
State and municipal securities |  |  |  |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value |  |  |  |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Less than 12 Months | 34,808,000 |  | 34,808,000 |  | 4,163,000
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, 12 Months or Longer | 568,000 |  | 568,000 |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Total | 35,376,000 |  | 35,376,000 |  | 4,163,000
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses |  |  |  |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Less than 12 Months | (451,000) |  | (451,000) |  | (63,000)
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, 12 Months or Longer | (10,000) |  | (10,000) |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Total | (461,000) |  | (461,000) |  | (63,000)
U.S. Treasuries |  |  |  |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value |  |  |  |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Less than 12 Months | 12,049,000 |  | 12,049,000 |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Total | 12,049,000 |  | 12,049,000 |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses |  |  |  |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Less than 12 Months | (78,000) |  | (78,000) |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Total | (78,000) |  | (78,000) |  |
Corporate bonds |  |  |  |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value |  |  |  |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Less than 12 Months | 2,244,000 |  | 2,244,000 |  | 1,198,000
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, 12 Months or Longer | 439,000 |  | 439,000 |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Fair Value, Total | 2,683,000 |  | 2,683,000 |  | 1,198,000
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses |  |  |  |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Less than 12 Months | (6,000) |  | (6,000) |  | (2,000)
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, 12 Months or Longer | (10,000) |  | (10,000) |  |
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Total | $ (16,000) |  | $ (16,000) |  | $ (2,000)

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