Investments - Schedule of Available-for-sale Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, at fair value	$ 3,096,708	$ 2,946,126
U.S. Government and Agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	9,817	9,822
Available-for-sale debt securities gross unrealized gain	57	7
Available-for-sale debt securities, gross unrealized loss	(205)	(326)
Available-for-sale debt securities, at fair value	9,669	9,503
Foreign Government [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	186,815	171,033
Available-for-sale debt securities gross unrealized gain	1,700	1,597
Available-for-sale debt securities, gross unrealized loss	(6,079)	(6,206)
Available-for-sale debt securities, at fair value	182,436	166,424
States and Political Subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	126,677	128,359
Available-for-sale debt securities gross unrealized gain	100	96
Available-for-sale debt securities, gross unrealized loss	(13,977)	(14,886)
Available-for-sale debt securities, at fair value	112,800	113,569
Corporates [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	1,990,113	1,929,350
Available-for-sale debt securities gross unrealized gain	19,854	11,853
Available-for-sale debt securities, gross unrealized loss	(90,960)	(116,095)
Available-for-sale debt securities, at fair value	1,919,007	1,825,108
Residential Mortgage-backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	628,760	552,611
Available-for-sale debt securities gross unrealized gain	2,219	536
Available-for-sale debt securities, gross unrealized loss	(58,313)	(66,590)
Available-for-sale debt securities, at fair value	572,666	486,557
Commercial Mortgage-backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	106,388	110,426
Available-for-sale debt securities gross unrealized gain	101	87
Available-for-sale debt securities, gross unrealized loss	(8,940)	(11,068)
Available-for-sale debt securities, at fair value	97,549	99,445
Other Asset-backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	206,131	250,882
Available-for-sale debt securities gross unrealized gain	1,252	1,396
Available-for-sale debt securities, gross unrealized loss	(4,802)	(6,758)
Available-for-sale debt securities, at fair value	202,581	245,520
Fixed-Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	3,254,701	3,152,483
Available-for-sale debt securities gross unrealized gain	25,283	15,572
Available-for-sale debt securities, gross unrealized loss	(183,276)	(221,929)
Available-for-sale debt securities, at fair value	$ 3,096,708	$ 2,946,126

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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