Investments - Available-for-sale Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	$ 141,951	$ 129,313
Debt securities, Gross Unrealized Gain	5,488	1,940
Debt securities, Gross Unrealized Losses	(551)	(253)
Debt securities, Estimated Fair Value	146,888	131,000
U.S. Government
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	9,778	9,392
Debt securities, Gross Unrealized Gain	292	66
Debt securities, Gross Unrealized Losses	0	(6)
Debt securities, Estimated Fair Value	10,070	9,452
State and local government
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	19,968	14,388
Debt securities, Gross Unrealized Gain	890	545
Debt securities, Gross Unrealized Losses	(1)	0
Debt securities, Estimated Fair Value	20,857	14,933
Corporate debt
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	47,741	39,550
Debt securities, Gross Unrealized Gain	2,712	865
Debt securities, Gross Unrealized Losses	(147)	(21)
Debt securities, Estimated Fair Value	50,306	40,394
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	24,951	19,549
Debt securities, Gross Unrealized Gain	260	81
Debt securities, Gross Unrealized Losses	(310)	(55)
Debt securities, Estimated Fair Value	24,901	19,575
Mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	23,187	31,389
Debt securities, Gross Unrealized Gain	590	238
Debt securities, Gross Unrealized Losses	0	(112)
Debt securities, Estimated Fair Value	23,777	31,515
Commercial mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	9,941	9,972
Debt securities, Gross Unrealized Gain	621	116
Debt securities, Gross Unrealized Losses	(81)	(45)
Debt securities, Estimated Fair Value	10,481	10,043
Collateralized mortgage obligations
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	6,385	5,073
Debt securities, Gross Unrealized Gain	123	29
Debt securities, Gross Unrealized Losses	(12)	(14)
Debt securities, Estimated Fair Value	$ 6,496	$ 5,088

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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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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