Investments - Schedule of Available-for-sale Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, at fair value	$ 2,554,465	$ 2,702,567
Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	2,777,820	2,621,388
Available-for-sale debt securities gross unrealized gain	5,143	95,045
Available-for-sale debt securities, gross unrealized loss	(228,498)	(13,866)
Available-for-sale debt securities, at fair value	2,554,465	2,702,567
Short-Term Investments
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	3,311	85,246
Available-for-sale debt securities gross unrealized gain		1
Available-for-sale debt securities, gross unrealized loss		(4)
Available-for-sale debt securities, at fair value	3,311	85,243
Fixed-Maturity Securities and Short-term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	2,781,131	2,706,634
Available-for-sale debt securities gross unrealized gain	5,143	95,046
Available-for-sale debt securities, gross unrealized loss	(228,498)	(13,870)
Available-for-sale debt securities, at fair value	2,557,776	2,787,810
U.S. Government and Agencies [Member] \| Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	32,924	32,292
Available-for-sale debt securities gross unrealized gain	46	187
Available-for-sale debt securities, gross unrealized loss	(718)	(79)
Available-for-sale debt securities, at fair value	32,252	32,400
Foreign Government [Member] \| Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	159,464	147,288
Available-for-sale debt securities gross unrealized gain	623	6,283
Available-for-sale debt securities, gross unrealized loss	(10,255)	(595)
Available-for-sale debt securities, at fair value	149,832	152,976
States and Political Subdivisions [Member] \| Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	143,750	147,455
Available-for-sale debt securities gross unrealized gain	247	6,326
Available-for-sale debt securities, gross unrealized loss	(14,457)	(254)
Available-for-sale debt securities, at fair value	129,540	153,527
Corporates [Member] \| Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	1,650,504	1,649,334
Available-for-sale debt securities gross unrealized gain	3,338	72,418
Available-for-sale debt securities, gross unrealized loss	(136,869)	(8,068)
Available-for-sale debt securities, at fair value	1,516,973	1,713,684
Residential Mortgage-backed Securities [Member] \| Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	484,034	373,753
Available-for-sale debt securities gross unrealized gain	701	5,108
Available-for-sale debt securities, gross unrealized loss	(45,673)	(3,230)
Available-for-sale debt securities, at fair value	439,062	375,631
Commercial Mortgage-backed Securities [Member] \| Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	145,360	142,631
Available-for-sale debt securities gross unrealized gain	6	3,314
Available-for-sale debt securities, gross unrealized loss	(9,861)	(420)
Available-for-sale debt securities, at fair value	135,505	145,525
Other Asset-backed Securities [Member] \| Fixed Maturities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	161,784	128,635
Available-for-sale debt securities gross unrealized gain	182	1,409
Available-for-sale debt securities, gross unrealized loss	(10,665)	(1,220)
Available-for-sale debt securities, at fair value	$ 151,301	$ 128,824

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, 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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