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Investment Securities - Amortized cost and estimated fair value (Details) - USD ($) $ in Thousands | Mar. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Carrying Value |  |
Due within one year or less | $ 5,797 |
Due after one year through five years | 40,296 |
Due after five years through ten years | 69,945 |
Due after 10 years | 16,395 |
Held-to-maturity securities carrying value | 132,433 |
Amortized Cost | 313,871 | $ 321,902
Estimated Fair Value |  |
Due within one year or less | 5,692 |
Due after one year through five years | 37,454 |
Due after five years through ten years | 60,959 |
Due after 10 years | 14,179 |
Total investment securities | 118,284 |
Debt Securities, Held-to-maturity, Fair Value, Total | 267,874 | 270,912
Amortized Cost |  |
Due after one year through five years | 17,549 |
Due after five years through ten years | 78,819 |
Due after 10 years | 45,438 |
Total investment securities available-for-sale | 141,806 |
Total investment securities, Amortized Cost | 833,140 |
Fair Value |  |
Due after one year through five years | 16,463 |
Due after five years through ten years | 66,742 |
Due after 10 years | 41,001 |
Total investment securities available-for-sale | 124,206 |
Debt Securities, Available-for-sale, Total | 705,825 | 717,324
Mortgage backed securities - Residential agency |  |
Carrying Value |  |
Mortgage-backed securities, Carrying value | 181,438 |
Amortized Cost | 181,438 | 184,115
Estimated Fair Value |  |
Mortgage-backed securities, Fair value | 149,590 |
Debt Securities, Held-to-maturity, Fair Value, Total | 149,590 | 150,861
Amortized Cost |  |
Mortgage-backed securities, Amortized Cost | 691,334 |
Fair Value |  |
Mortgage-backed securities, Fair value | 581,619 |
Debt Securities, Available-for-sale, Total | $ 581,619 | $ 587,679

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