Investment Securities - Summary Of The Amortized Cost And Estimated Fair Value Of Securities (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Amortized cost	$ 38,468	$ 28,115
Gross unrealized gains	1,259	445
Gross unrealized losses	(4)	(5)
Estimated fair value	39,723	28,555
Corporate bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized cost	7,021	0
Gross unrealized gains	250	0
Gross unrealized losses	0	0
Estimated fair value	7,271	0
Mortgage backed securities [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized cost	28,977	20,291
Gross unrealized gains	1,009	436
Gross unrealized losses	0	(5)
Estimated fair value	29,986	20,722
Government agencies [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized cost	2,470	7,824
Gross unrealized gains	0	9
Gross unrealized losses	(4)	0
Estimated fair value	$ 2,466	$ 7,833

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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