Investments - Schedule of Other Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Other Investments
Fair Value	$ 246,499	$ 281,001
Other Long-term Investments
Other Investments
Cost or adjusted/amortized cost	36,167	22,969
Unrealized Gain	660	654
Unrealized Loss	0	0
Fair Value	36,827	23,623
Limited Partnership
Other Investments
Cost or adjusted/amortized cost	2,778	2,556
Unrealized Gain	639	573
Unrealized Loss	0	0
Fair Value of Limited Partnership Interest	3,417	3,129
Surplus Note
Other Investments
Cost or adjusted/amortized cost	6,000
Unrealized Gain	0
Unrealized Loss	0
Fair Value	6,000
Commercial Mortgage Loans
Other Investments
Cost or adjusted/amortized cost	6,840
Unrealized Gain	0
Unrealized Loss	0
Fair Value	6,840
Short-term Investments
Other Investments
Cost or adjusted/amortized cost	20,549	20,413
Unrealized Gain	21	81
Unrealized Loss	0	0
Fair Value	$ 20,570	$ 20,494

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