Investments - Schedule of Available-for-sale Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, at fair value	$ 3,471,682	$ 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	8,935	9,814
Available-for-sale debt securities gross unrealized gain	13	65
Available-for-sale debt securities, gross unrealized loss	(120)	(137)
Available-for-sale debt securities, at fair value	8,828	9,742
Foreign Government [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	163,667	173,732
Available-for-sale debt securities gross unrealized gain	1,581	1,587
Available-for-sale debt securities, gross unrealized loss	(5,524)	(6,286)
Available-for-sale debt securities, at fair value	159,724	169,033
States and Political Subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	134,946	136,996
Available-for-sale debt securities gross unrealized gain	1,263	953
Available-for-sale debt securities, gross unrealized loss	(11,013)	(11,017)
Available-for-sale debt securities, at fair value	125,196	126,932
Corporates [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	2,266,740	2,042,691
Available-for-sale debt securities gross unrealized gain	18,194	27,386
Available-for-sale debt securities, gross unrealized loss	(84,283)	(74,204)
Available-for-sale debt securities, at fair value	2,200,651	1,995,873
Residential Mortgage-backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	694,542	687,149
Available-for-sale debt securities gross unrealized gain	4,219	5,892
Available-for-sale debt securities, gross unrealized loss	(53,146)	(47,176)
Available-for-sale debt securities, at fair value	645,615	645,865
Commercial Mortgage-backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	85,346	92,035
Available-for-sale debt securities gross unrealized gain	54	120
Available-for-sale debt securities, gross unrealized loss	(6,976)	(7,123)
Available-for-sale debt securities, at fair value	78,424	85,032
Other Asset-backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	257,784	236,201
Available-for-sale debt securities gross unrealized gain	375	816
Available-for-sale debt securities, gross unrealized loss	(4,915)	(4,248)
Available-for-sale debt securities, at fair value	253,244	232,769
Fixed-Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	3,611,960	3,378,618
Available-for-sale debt securities gross unrealized gain	25,699	36,819
Available-for-sale debt securities, gross unrealized loss	(165,977)	(150,191)
Available-for-sale debt securities, at fair value	3,471,682	$ 3,265,246
Short-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	4,953
Available-for-sale debt securities gross unrealized gain	0
Available-for-sale debt securities, gross unrealized loss	(3)
Available-for-sale debt securities, at fair value	4,950
Fixed-Maturity Securities and Short-term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities, amortized cost basis	3,616,913
Available-for-sale debt securities gross unrealized gain	25,699
Available-for-sale debt securities, gross unrealized loss	(165,980)
Available-for-sale debt securities, at fair value	$ 3,476,632

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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