Investment Securities - Summary Of The Amortized Cost And Estimated Fair Value Of Securities (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized cost	$ 81,793	$ 54,183
Gross unrealized gains	1,040	1,103
Gross unrealized losses	(725)	(193)
Estimated fair value	82,108	55,093
Corporate bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized cost	36,352	24,224
Gross unrealized gains	589	434
Gross unrealized losses	(365)	(170)
Estimated fair value	36,576	24,488
Mortgage backed securities [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized cost	43,324	27,541
Gross unrealized gains	416	669
Gross unrealized losses	(360)	(17)
Estimated fair value	43,380	28,193
Government agencies [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized cost	2,117	2,418
Gross unrealized gains	35	0
Gross unrealized losses	0	(6)
Estimated fair value	$ 2,152	$ 2,412

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on 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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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on 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).

+ References

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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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