Note 3 - Investments (Details Textual)	12 Months Ended
Dec. 31, 2025 USD ($) FixedMaturitySecurities	Dec. 31, 2024 USD ($) FixedMaturitySecurities	Dec. 31, 2023 USD ($)
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions \| FixedMaturitySecurities	391	595
Debt Securities, Available-for-Sale, Unrealized Loss Position	$ 375,350,000	$ 663,972,000
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss	19,511,000	37,257,000
Proceeds from Sale of Debt Securities, Available-for-Sale	28,000,000	6,300,000	$ 10,100,000
Proceeds from Sale of Equity Securities, FV-NI	6,400,000
Debt Securities, Available-for-sale	1,224,187,000	939,046,000
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments	124,300,000
Debt Securities, Available-for-Sale, Allowance for Credit Loss	0	244,000
Securities on Deposit With State Regulatory Authorities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale	$ 13,500,000	$ 9,900,000

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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