Investment Securities - Summary Of The Amortized Cost And Estimated Fair Value Of Securities (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized cost	$ 57,938	$ 54,183
Gross unrealized gains	1,038	1,103
Gross unrealized losses	(871)	(193)
Estimated fair value	58,105	55,093
Corporate bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized cost	26,241	24,224
Gross unrealized gains	500	434
Gross unrealized losses	(459)	(170)
Estimated fair value	26,282	24,488
Mortgage backed securities [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized cost	29,305	27,541
Gross unrealized gains	538	669
Gross unrealized losses	(405)	(17)
Estimated fair value	29,438	28,193
Government agencies [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized cost	2,392	2,418
Gross unrealized gains	0	0
Gross unrealized losses	(7)	(6)
Estimated fair value	$ 2,385	$ 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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