Securities - Amortized Cost and Fair Value of Securities by Contractual Maturity (Detail) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Investments Debt And Equity Securities [Abstract]
Amortized Cost, Due in one year or less	$ 6,449
Amortized Cost, Due after one year through five years	50,074
Amortized Cost, Due after five years through ten years	66,175
Amortized Cost, Due after ten years	300,333
Amortized Cost, Mortgage-backed securities	261,324
Amortized Cost, Total securities available for sale	684,355	$ 682,351
Fair Value, Due in one year or less	6,299
Fair Value, Due after one year through five years	47,145
Fair Value, Due after five years through ten years	62,011
Fair Value, Due after ten years	277,696
Fair Value, Mortgage-backed securities	234,556
Fair Value, Total securities available for sale	$ 627,707	$ 615,402

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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