Investments - Available-for-sale Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	$ 148,434	$ 149,954
Debt securities, Gross Unrealized Gain	1,279	2,196
Debt securities, Gross Unrealized Losses	(2,084)	(151)
Debt securities, Estimated Fair Value	147,629	151,999
U.S. Government
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	22,015	30,743
Debt securities, Gross Unrealized Gain	172	225
Debt securities, Gross Unrealized Losses	(27)	(1)
Debt securities, Estimated Fair Value	22,160	30,967
State and local government
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	31,896	32,253
Debt securities, Gross Unrealized Gain	584	1,040
Debt securities, Gross Unrealized Losses	(601)	(28)
Debt securities, Estimated Fair Value	31,879	33,265
Corporate debt
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	16,379	19,015
Debt securities, Gross Unrealized Gain	172	311
Debt securities, Gross Unrealized Losses	(410)	(23)
Debt securities, Estimated Fair Value	16,141	19,303
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	31,905	20,987
Debt securities, Gross Unrealized Gain	36	49
Debt securities, Gross Unrealized Losses	(118)	(73)
Debt securities, Estimated Fair Value	31,823	20,963
Mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	36,724	38,512
Debt securities, Gross Unrealized Gain	184	345
Debt securities, Gross Unrealized Losses	(861)	(3)
Debt securities, Estimated Fair Value	36,047	38,854
Commercial mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	1,849	2,083
Debt securities, Gross Unrealized Gain	40	65
Debt securities, Gross Unrealized Losses	(32)	(22)
Debt securities, Estimated Fair Value	1,857	2,126
Collateralized mortgage obligations
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	7,666	6,361
Debt securities, Gross Unrealized Gain	91	161
Debt securities, Gross Unrealized Losses	(35)	(1)
Debt securities, Estimated Fair Value	$ 7,722	$ 6,521

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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