Investments - Available for Sale Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Available for sale investments
Amortized Cost	$ 397,955	$ 381,279
Gross Unrealized Gains	11,731	17,221
Gross Unrealized Losses	(1,640)	(513)
Fair Value	408,046	397,987
U.S. Governments
Available for sale investments
Amortized Cost	18,965	16,308
Gross Unrealized Gains	461	756
Gross Unrealized Losses	(115)	(5)
Fair Value	19,311	17,059
States, territories, and possessions
Available for sale investments
Amortized Cost	6,171	6,208
Gross Unrealized Gains	348	428
Gross Unrealized Losses	(118)
Fair Value	6,401	6,636
Political subdivisions
Available for sale investments
Amortized Cost	1,494	2,027
Gross Unrealized Gains	94	125
Fair Value	1,588	2,152
Special revenue excluding mortgage/asset-backed securities
Available for sale investments
Amortized Cost	43,376	39,704
Gross Unrealized Gains	1,228	1,525
Gross Unrealized Losses	(174)	(2)
Fair Value	44,430	41,227
Corporate and other
Available for sale investments
Amortized Cost	248,480	234,049
Gross Unrealized Gains	7,751	11,602
Gross Unrealized Losses	(1,131)	(291)
Fair Value	255,100	245,360
Mortgage/asset-backed securities
Available for sale investments
Amortized Cost	79,469	82,983
Gross Unrealized Gains	1,849	2,785
Gross Unrealized Losses	(102)	(215)
Fair Value	$ 81,216	$ 85,553

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 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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