Investment Securities and Other Investments - Summary of Investments Classified by Contractual Maturity Date (Detail) $ in Thousands	Sep. 30, 2023 USD ($)
Schedule of Investments [Abstract]
Debt Securities Available for Sale, Amortized Cost, Due in one year or less	$ 2
Debt Securities Available for Sale, Amortized Cost, Due after one year through five years	40,689
Debt Securities Available for Sale, Amortized Cost, Due after five years through ten years	131,518
Debt Securities Available for Sale, Amortized Cost, Due after ten years	211,522
Total	383,731
Debt Securities Available for Sale, Fair Value, Due in one year or less	2
Debt Securities Available for Sale, Fair Value, Due after one year through five years	36,416
Debt Securities Available for Sale, Fair Value, Due after five years through ten years	109,844
Debt Securities Available for Sale, Fair Value, Due after ten years	167,668
Total	$ 313,930

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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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).

+ References

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