Investments - Schedule of Available-for-sale Securities, at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 332,988	$ 286,360
Gross unrealized gains	4,070	650
Gross unrealized losses	(1,866)	(3,447)
Fair value	335,192	283,563
U.S. Treasury securities and obligations of U.S. government authorities and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	189,596	71,945
Gross unrealized gains	2,138	266
Gross unrealized losses	(144)	(463)
Fair value	191,590	71,748
Obligations of state and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	45,249	67,624
Gross unrealized gains	1,104	280
Gross unrealized losses	(15)	(458)
Fair value	46,338	67,446
Corporate securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	50,514	96,888
Gross unrealized gains	719	78
Gross unrealized losses	(2)	(1,241)
Fair value	51,231	95,725
Asset backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	45,634	41,912
Gross unrealized gains	89	14
Gross unrealized losses	(1,705)	(1,274)
Fair value	44,018	40,652
Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	896	1,241
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Fair value	896	1,241
Obligations of foreign governments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,099	6,750
Gross unrealized gains	20	12
Gross unrealized losses	0	(11)
Fair value	$ 1,119	$ 6,751

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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-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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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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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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