Investment Securities - Amortized Cost and Fair Value - Held-to-maturity Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Securities Held-to-Maturity
Amortized cost	$ 96,347	$ 99,415
Gross unrealized (losses)	(20,614)	(18,254)
Securities held-to-maturity, fair value		81,161
Securities held-to-maturity, fair value.	75,733
U.S Treasuries
Securities Held-to-Maturity
Amortized cost	6,001	6,000
Gross unrealized (losses)	(873)	(840)
Securities held-to-maturity, fair value		5,160
Securities held-to-maturity, fair value.	5,128
U.S. government and federal agencies
Securities Held-to-Maturity
Amortized cost	35,463	35,551
Gross unrealized (losses)	(6,743)	(6,135)
Securities held-to-maturity, fair value		29,416
Securities held-to-maturity, fair value.	28,720
Collateralized mortgage obligations
Securities Held-to-Maturity
Amortized cost	19,773	21,275
Gross unrealized (losses)	(4,920)	(4,227)
Securities held-to-maturity, fair value		17,048
Securities held-to-maturity, fair value.	14,853
Taxable municipal
Securities Held-to-Maturity
Amortized cost	6,061	6,073
Gross unrealized (losses)	(1,409)	(1,364)
Securities held-to-maturity, fair value		4,709
Securities held-to-maturity, fair value.	4,652
Mortgage-backed
Securities Held-to-Maturity
Amortized cost	29,049	30,516
Gross unrealized (losses)	(6,669)	(5,688)
Securities held-to-maturity, fair value		$ 24,828
Securities held-to-maturity, fair value.	$ 22,380

Fair value of investment in debt security measured at amortized cost excluding accrued interest (held-to-maturity).

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Amount excluding accrued interest, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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