Investments - Available-for-sale Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	$ 148,699	$ 149,954
Debt securities, Gross Unrealized Gain	1,413	2,196
Debt securities, Gross Unrealized Losses	(924)	(151)
Debt securities, Estimated Fair Value	149,188	151,999
U.S. Government
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	21,936	30,743
Debt securities, Gross Unrealized Gain	148	225
Debt securities, Gross Unrealized Losses	(27)	(1)
Debt securities, Estimated Fair Value	22,057	30,967
State and local government
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	31,467	32,253
Debt securities, Gross Unrealized Gain	778	1,040
Debt securities, Gross Unrealized Losses	(74)	(28)
Debt securities, Estimated Fair Value	32,171	33,265
Corporate debt
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	19,989	19,015
Debt securities, Gross Unrealized Gain	162	311
Debt securities, Gross Unrealized Losses	(208)	(23)
Debt securities, Estimated Fair Value	19,943	19,303
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	31,691	20,987
Debt securities, Gross Unrealized Gain	28	49
Debt securities, Gross Unrealized Losses	(92)	(73)
Debt securities, Estimated Fair Value	31,627	20,963
Mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	34,811	38,512
Debt securities, Gross Unrealized Gain	145	345
Debt securities, Gross Unrealized Losses	(499)	(3)
Debt securities, Estimated Fair Value	34,457	38,854
Commercial mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	1,844	2,083
Debt securities, Gross Unrealized Gain	62	65
Debt securities, Gross Unrealized Losses	0	(22)
Debt securities, Estimated Fair Value	1,906	2,126
Collateralized mortgage obligations
Debt Securities, Available-for-sale [Line Items]
Debt securities, Cost or Amortized Cost	6,961	6,361
Debt securities, Gross Unrealized Gain	90	161
Debt securities, Gross Unrealized Losses	(24)	(1)
Debt securities, Estimated Fair Value	$ 7,027	$ 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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