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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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