Investments - Summary of Amortized Cost and Fair Values of Fixed Maturity Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Cost	$ 35,122	$ 31,811
Gross unrealized gains	786	242
Gross unrealized losses	(9)	(47)
Fair value	35,899	32,006
U.S. Treasury securities, obligations of U.S. Government agencies and municipalities
Debt Securities, Available-for-sale [Line Items]
Cost	28,733	26,487
Gross unrealized gains	537	174
Gross unrealized losses	(7)	(39)
Fair value	29,263	26,622
Corporate debt
Debt Securities, Available-for-sale [Line Items]
Cost	6,389	5,324
Gross unrealized gains	249	68
Gross unrealized losses	(2)	(8)
Fair value	$ 6,636	$ 5,384

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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