Investments - Summary of Amortized Cost and Fair Values of Fixed Maturity Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Cost	$ 35,562	$ 31,811
Gross unrealized gains	703	242
Gross unrealized losses	(11)	(47)
Fair value	36,254	32,006
U.S. Treasury securities, obligations of U.S. Government agencies and Municipalities
Debt Securities, Available-for-sale [Line Items]
Cost	28,372	26,487
Gross unrealized gains	464	174
Gross unrealized losses	(5)	(39)
Fair value	28,831	26,622
Corporate debt
Debt Securities, Available-for-sale [Line Items]
Cost	7,190	5,324
Gross unrealized gains	239	68
Gross unrealized losses	(6)	(8)
Fair value	$ 7,423	$ 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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