Securities - Amortized Cost and Fair Value of Debt Securities, by Contractual Maturity (Detail) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Available For Sale Securities Debt Maturities [Abstract]
Amortized Cost, One year or less	$ 18,764
Amortized Cost, After one year through five years	211,418
Amortized Cost, After five years through ten years	79,611
Amortized Cost, After ten years	4,310
Amortized Cost, Total	314,103
Amortized Cost, Mortgage-backed securities	98,348
Amortized Cost	412,451	$ 439,186
Fair Value, One year or less	18,352
Fair Value, After one year through five years	193,248
Fair Value, After five years through ten years	70,746
Fair Value, After ten years	4,309
Fair Value, Total	286,655
Fair Value, Mortgage-backed securities	86,320
Total, Fair Value	$ 372,975	$ 390,789

Available for sale debt securities amortized cost basis excluding mortgage backed securities.

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Available for sale securities debt maturities fair value excluding mortgage backed securities.

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Mortgage backed securities available for sale amortized cost.

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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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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), 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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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), 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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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth 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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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth 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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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), 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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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next 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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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next 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 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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Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as available-for-sale.

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No definition available.

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