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Investment Securities - Fair value of securities held-to-maturity and available-for-sale (Details) - USD ($) $ in Thousands | Mar. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Held-to-maturity, Fair Value |  |
Fair Value, Less than 12 Months | $ 64,331 | $ 94,506
Fair Value, 12 Months or Longer | 30,720 | 8,751
Fair Value | 95,051 | 103,257
Gross Unrealized Losses |  |
Gross Unrealized Losses, Less than 12 Months | (6,000) | (2,035)
Gross Unrealized Losses, 12 Months or Longer | (3,126) | (216)
Gross Unrealized Losses | (9,126) | (2,251)
Available-for-sale, Fair Value |  |
Fair Value, Less than 12 Months | 239,755 | 168,443
Fair Value, 12 Months or Longer | 30,400 | 7,795
Fair Value | 270,155 | 176,238
Gross Unrealized Losses |  |
Gross Unrealized Losses, Less than 12 Months | (11,585) | (2,723)
Gross Unrealized Losses, 12 Months or Longer | (2,882) | (269)
Gross Unrealized Losses | (14,467) | (2,992)
U.S Treasuries |  |
Held-to-maturity, Fair Value |  |
Fair Value, Less than 12 Months | 5,510 | 5,851
Fair Value | 5,510 | 5,851
Gross Unrealized Losses |  |
Gross Unrealized Losses, Less than 12 Months | (491) | (150)
Gross Unrealized Losses | (491) | (150)
Available-for-sale, Fair Value |  |
Fair Value, Less than 12 Months | 40,683 | 30,543
Fair Value | 40,683 | 30,543
Gross Unrealized Losses |  |
Gross Unrealized Losses, Less than 12 Months | (2,203) | (411)
Gross Unrealized Losses | (2,203) | (411)
U.S. government and federal agencies |  |
Held-to-maturity, Fair Value |  |
Fair Value, Less than 12 Months | 19,818 | 31,617
Fair Value, 12 Months or Longer | 12,894 | 3,376
Fair Value | 32,712 | 34,993
Gross Unrealized Losses |  |
Gross Unrealized Losses, Less than 12 Months | (1,796) | (645)
Gross Unrealized Losses, 12 Months or Longer | (1,165) | (81)
Gross Unrealized Losses | (2,961) | (726)
Available-for-sale, Fair Value |  |
Fair Value, Less than 12 Months | 17,569 | 14,154
Fair Value, 12 Months or Longer | 13,370 | 6,877
Fair Value | 30,939 | 21,031
Gross Unrealized Losses |  |
Gross Unrealized Losses, Less than 12 Months | (619) | (301)
Gross Unrealized Losses, 12 Months or Longer | (1,222) | (223)
Gross Unrealized Losses | (1,841) | (524)
Collateralized mortgage obligations |  |
Held-to-maturity, Fair Value |  |
Fair Value, Less than 12 Months | 20,407 | 25,072
Fair Value, 12 Months or Longer | 1,618 |
Fair Value | 22,025 | 25,072
Gross Unrealized Losses |  |
Gross Unrealized Losses, Less than 12 Months | (1,918) | (534)
Gross Unrealized Losses, 12 Months or Longer | (176) |
Gross Unrealized Losses | (2,094) | (534)
Available-for-sale, Fair Value |  |
Fair Value, Less than 12 Months | 33,514 | 30,352
Fair Value, 12 Months or Longer | 3,284 |
Fair Value | 36,798 | 30,352
Gross Unrealized Losses |  |
Gross Unrealized Losses, Less than 12 Months | (2,230) | (726)
Gross Unrealized Losses, 12 Months or Longer | (326) |
Gross Unrealized Losses | (2,556) | (726)
Taxable municipal |  |
Held-to-maturity, Fair Value |  |
Fair Value, Less than 12 Months | 1,367 | 3,971
Fair Value, 12 Months or Longer | 4,056 | 1,923
Fair Value | 5,423 | 5,894
Gross Unrealized Losses |  |
Gross Unrealized Losses, Less than 12 Months | (184) | (133)
Gross Unrealized Losses, 12 Months or Longer | (478) | (61)
Gross Unrealized Losses | (662) | (194)
Available-for-sale, Fair Value |  |
Fair Value, Less than 12 Months |  | 265
Fair Value, 12 Months or Longer | 252 |
Fair Value | 252 | 265
Gross Unrealized Losses |  |
Gross Unrealized Losses, Less than 12 Months |  | (5)
Gross Unrealized Losses, 12 Months or Longer | (18) |
Gross Unrealized Losses | (18) | (5)
Mortgage-backed |  |
Held-to-maturity, Fair Value |  |
Fair Value, Less than 12 Months | 17,229 | 27,995
Fair Value, 12 Months or Longer | 12,152 | 3,452
Fair Value | 29,381 | 31,447
Gross Unrealized Losses |  |
Gross Unrealized Losses, Less than 12 Months | (1,611) | (573)
Gross Unrealized Losses, 12 Months or Longer | (1,307) | (74)
Gross Unrealized Losses | (2,918) | (647)
Available-for-sale, Fair Value |  |
Fair Value, Less than 12 Months | 143,279 | 93,129
Fair Value, 12 Months or Longer | 13,494 | 918
Fair Value | 156,773 | 94,047
Gross Unrealized Losses |  |
Gross Unrealized Losses, Less than 12 Months | (6,306) | (1,280)
Gross Unrealized Losses, 12 Months or Longer | (1,316) | (46)
Gross Unrealized Losses | (7,622) | $ (1,326)
Corporate bonds |  |
Available-for-sale, Fair Value |  |
Fair Value, Less than 12 Months | 1,965 |
Fair Value | 1,965 |
Gross Unrealized Losses |  |
Gross Unrealized Losses, Less than 12 Months | (35) |
Gross Unrealized Losses | (35) |
Tax-exempt municipal |  |
Available-for-sale, Fair Value |  |
Fair Value, Less than 12 Months | 2,745 |
Fair Value | 2,745 |
Gross Unrealized Losses |  |
Gross Unrealized Losses, Less than 12 Months | (192) |
Gross Unrealized Losses | $ (192) |

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