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Securities - Continuous Unrealized Loss Position (Details) $ in Thousands | 3 Months Ended | 12 Months Ended
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Mar. 31, 2024 USD ($) security | Dec. 31, 2023 USD ($) security
Fair value and gross unrealized losses of securities with unrealized losses, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position |  |
Number of Holdings with unrealized losses | security | 519 | 521
Less Than 12 Months, Fair Value | $ 92,970 | $ 95,041
Less Than 12 Months, Unrealized Losses | (1,071) | (1,320)
12 Months or Greater, Fair Value | 375,116 | 378,544
12 Months or Greater, Unrealized Losses | (45,990) | (46,522)
Fair Value | 468,086 | 473,585
Unrealized Losses | $ (47,061) | $ (47,842)
Percentage debt securities with aggregate depreciation from amortized cost basis | 9.10% | 9.20%
Allowance for available for sale securities | $ 0 | $ 0
Accrued interest receivable on securities | $ 5,200 | $ 4,900
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] | Interest Receivable | Interest Receivable
Municipal Bonds |  |
Fair value and gross unrealized losses of securities with unrealized losses, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position |  |
Number of Holdings with unrealized losses | security | 215 | 212
Less Than 12 Months, Fair Value | $ 7,862 | $ 4,052
Less Than 12 Months, Unrealized Losses | (44) | (17)
12 Months or Greater, Fair Value | 122,437 | 120,527
12 Months or Greater, Unrealized Losses | (19,114) | (19,018)
Fair Value | 130,299 | 124,579
Unrealized Losses | $ (19,158) | $ (19,035)
Mortgage-Backed Securities |  |
Fair value and gross unrealized losses of securities with unrealized losses, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position |  |
Number of Holdings with unrealized losses | security | 129 | 128
Less Than 12 Months, Fair Value | $ 42,583 | $ 35,719
Less Than 12 Months, Unrealized Losses | (665) | (310)
12 Months or Greater, Fair Value | 124,205 | 135,829
12 Months or Greater, Unrealized Losses | (16,742) | (16,091)
Fair Value | 166,788 | 171,548
Unrealized Losses | $ (17,407) | $ (16,401)
Corporate Securities |  |
Fair value and gross unrealized losses of securities with unrealized losses, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position |  |
Number of Holdings with unrealized losses | security | 113 | 110
Less Than 12 Months, Fair Value | $ 16,148 | $ 14,528
Less Than 12 Months, Unrealized Losses | (290) | (756)
12 Months or Greater, Fair Value | 105,583 | 101,311
12 Months or Greater, Unrealized Losses | (9,957) | (11,123)
Fair Value | 121,731 | 115,839
Unrealized Losses | $ (10,247) | $ (11,879)
SBA Securities |  |
Fair value and gross unrealized losses of securities with unrealized losses, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position |  |
Number of Holdings with unrealized losses | security | 45 | 47
Less Than 12 Months, Fair Value | $ 1,973 | $ 1,731
Less Than 12 Months, Unrealized Losses | (5) | (3)
12 Months or Greater, Fair Value | 6,296 | 7,072
12 Months or Greater, Unrealized Losses | (86) | (99)
Fair Value | 8,269 | 8,803
Unrealized Losses | $ (91) | $ (102)
Asset-Backed Securities |  |
Fair value and gross unrealized losses of securities with unrealized losses, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position |  |
Number of Holdings with unrealized losses | security | 17 | 24
Less Than 12 Months, Fair Value | $ 24,404 | $ 39,011
Less Than 12 Months, Unrealized Losses | (67) | (234)
12 Months or Greater, Fair Value | 16,595 | 13,805
12 Months or Greater, Unrealized Losses | (91) | (191)
Fair Value | 40,999 | 52,816
Unrealized Losses | $ (158) | $ (425)

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