Investment Securities - Summary of Maturities Available for Sale Investment Securities (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Amortized Cost Available for sale securities:
One to five years	$ 22,145
Five to ten years	14,846
Beyond ten years	5,426
Securities not due at a single maturity date	39,376
Total available for sale securities	81,793	$ 54,183
Fair Value Available for sale securities:
One to five years	22,317
Five to ten years	15,061
Beyond ten years	5,209
Securities not due at a single maturity date	39,521
Total available for sale securities	$ 82,108	$ 55,093

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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