Note 3 - Investments and Restricted Investments - Investments and Restricted Investments (Details) $ in Thousands	Jun. 30, 2023 USD ($)
Investments, due within one year	$ 17,122
Restricted investments, due within one year	97,418
Investments,due on year through five years	0
Restricted investments, due on year through five years	16,753
Investments, total	17,122
Restricted investments, total	$ 114,171

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