Investment Securities - Summary of Fixed Maturity Securities Available for Sale (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 44,191	$ 48,614
Gross Unrealized Gains	1,808	597
Gross Unrealized Losses	(8)	(213)
Fair Value	45,991	48,998
Mortgage-backed Securities, Principally Obligations of US Federal Agencies [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	35,965	36,335
Gross Unrealized Gains	1,571	411
Gross Unrealized Losses	(8)	(112)
Fair Value	37,528	36,634
State and Municipalities [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	8,226	12,279
Gross Unrealized Gains	237	186
Gross Unrealized Losses		(101)
Fair Value	$ 8,463	$ 12,364

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).

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