Note 2 - Investments (Details Textual) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026 USD ($) FixedMaturitySecurities	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($) FixedMaturitySecurities	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($) FixedMaturitySecurities
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions \| FixedMaturitySecurities	739		739		391
Debt Securities, Available-for-Sale, Unrealized Loss Position	$ 904,454		$ 904,454		$ 375,350
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss	28,071		28,071		19,511
Proceeds from Sale of Debt Securities, Available-for-Sale	32,300	$ 3,000	47,700	$ 8,800
Proceeds from Sale of Equity Securities, FV-NI		$ 4,600		$ 6,400
Debt Securities, Available-for-sale	1,502,860		1,502,860		1,224,187
Other investments	45,877		45,877		28,503
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments	164,300		164,300
Partnership [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Other investments	40,900		40,900
Securities on Deposit With State Regulatory Authorities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale	$ 18,100		$ 18,100		$ 13,500

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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