Investment Securities - Estimated Fair Value of Contractual Maturities - Held-to-Maturity Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date [Abstract]
Maturing within one year	$ 145
Maturing after one year through five years	2,413
Maturing after five years through ten years	19,895
Maturing after ten years	155,325
Securities not due at a single maturity date, Amortized Cost	142,295
Amortized Cost	320,073	$ 336,944
Debt Securities, Held-to-Maturity, Maturity, Allocated and Single Maturity Date, Fair Value [Abstract]
Maturing within one year, Fair Value	145
Maturing after one year through five years, Fair Value	2,384
Maturing after five years through ten years, Fair Value	18,350
Maturing after ten years, Fair Value	162,191
Securities not due at a single maturity date, Fair Value	131,854
Estimated Fair Value	314,924	328,011
Mortgage-Backed Securities [Member]
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date [Abstract]
Amortized Cost	142,295	157,473
Debt Securities, Held-to-Maturity, Maturity, Allocated and Single Maturity Date, Fair Value [Abstract]
Estimated Fair Value	$ 131,854	$ 147,558

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Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) with single maturity date and allocated without single maturity date, maturing after tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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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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