Investments - Schedule of Available-for-sale Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, at fair value	$ 3,444,026	$ 3,265,246
U.S. Government and Agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	9,812	9,814
Available-for-sale debt securities gross unrealized gain	34	65
Available-for-sale debt securities, gross unrealized loss	(127)	(137)
Available-for-sale debt securities, at fair value	9,719	9,742
Foreign Government [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	173,243	173,732
Available-for-sale debt securities gross unrealized gain	1,086	1,587
Available-for-sale debt securities, gross unrealized loss	(7,096)	(6,286)
Available-for-sale debt securities, at fair value	167,233	169,033
States and Political Subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	135,903	136,996
Available-for-sale debt securities gross unrealized gain	604	953
Available-for-sale debt securities, gross unrealized loss	(11,510)	(11,017)
Available-for-sale debt securities, at fair value	124,997	126,932
Corporates [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	2,206,510	2,042,691
Available-for-sale debt securities gross unrealized gain	16,105	27,386
Available-for-sale debt securities, gross unrealized loss	(93,677)	(74,204)
Available-for-sale debt securities, at fair value	2,128,938	1,995,873
Residential Mortgage-backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	691,744	687,149
Available-for-sale debt securities gross unrealized gain	4,381	5,892
Available-for-sale debt securities, gross unrealized loss	(51,978)	(47,176)
Available-for-sale debt securities, at fair value	644,147	645,865
Commercial Mortgage-backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	90,721	92,035
Available-for-sale debt securities gross unrealized gain	72	120
Available-for-sale debt securities, gross unrealized loss	(7,203)	(7,123)
Available-for-sale debt securities, at fair value	83,590	85,032
Other Asset-backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	289,773	236,201
Available-for-sale debt securities gross unrealized gain	506	816
Available-for-sale debt securities, gross unrealized loss	(4,877)	(4,248)
Available-for-sale debt securities, at fair value	285,402	232,769
Fixed-Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	3,597,706	3,378,618
Available-for-sale debt securities gross unrealized gain	22,788	36,819
Available-for-sale debt securities, gross unrealized loss	(176,468)	(150,191)
Available-for-sale debt securities, at fair value	$ 3,444,026	$ 3,265,246

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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