Note 5 - Fair Value Measurements - Unobservable Inputs (Details) - Fair Value, Recurring [Member] - Fair Value, Inputs, Level 3 [Member] $ in Thousands	Jun. 30, 2026 USD ($)	Dec. 31, 2025 USD ($)
Long-term investments	$ 228,578	$ 238,566
Senior Secured Loan Two [Member] \| Minimum [Member] \| Measurement Input, Long-Term Revenue Growth Rate [Member]
Investment owned, measurement input	0.02	0.02
Senior Secured Loan Two [Member] \| Maximum [Member] \| Measurement Input, Long-Term Revenue Growth Rate [Member]
Investment owned, measurement input	0.02	0.02
Senior Secured Loan Two [Member] \| Weighted Average [Member] \| Measurement Input, Long-Term Revenue Growth Rate [Member]
Investment owned, measurement input	0.02	0.02
Senior Secured Loan Three [Member] \| Minimum [Member] \| Measurement Input, Long-Term Revenue Growth Rate [Member]
Investment owned, measurement input	0.01	0.01
Senior Secured Loan Three [Member] \| Maximum [Member] \| Measurement Input, Long-Term Revenue Growth Rate [Member]
Investment owned, measurement input	0.02	0.01
Senior Secured Loan Three [Member] \| Weighted Average [Member] \| Measurement Input, Long-Term Revenue Growth Rate [Member]
Investment owned, measurement input	0.017	0.01
Valuation, Market Approach [Member] \| Senior Secured Loan One [Member]
Long-term investments	$ 219,921	$ 225,328
Valuation, Market Approach [Member] \| Senior Secured Loan One [Member] \| Minimum [Member] \| Measurement Input, Discount Rate [Member]
Investment owned, measurement input	0.068	0.072
Valuation, Market Approach [Member] \| Senior Secured Loan One [Member] \| Maximum [Member] \| Measurement Input, Discount Rate [Member]
Investment owned, measurement input	0.114	0.112
Valuation, Market Approach [Member] \| Senior Secured Loan One [Member] \| Weighted Average [Member] \| Measurement Input, Discount Rate [Member]
Investment owned, measurement input	0.081	0.084
Valuation, Market Approach [Member] \| Senior Secured Loan Two [Member]
Long-term investments	$ 5,067	$ 9,431
Valuation, Market Approach [Member] \| Senior Secured Loan Two [Member] \| Minimum [Member] \| Measurement Input, Discount Rate [Member]
Investment owned, measurement input	0.09	0.129
Valuation, Market Approach [Member] \| Senior Secured Loan Two [Member] \| Maximum [Member] \| Measurement Input, Discount Rate [Member]
Investment owned, measurement input	0.147	0.143
Valuation, Market Approach [Member] \| Senior Secured Loan Two [Member] \| Weighted Average [Member] \| Measurement Input, Discount Rate [Member]
Investment owned, measurement input	0.127	0.135
Valuation Technique, Price of Comparable Business [Member] \| Senior Secured Loan One [Member] \| Minimum [Member] \| Measurement Input, EBITDA Multiple [Member]
Investment owned, measurement input	5	5.4
Valuation Technique, Price of Comparable Business [Member] \| Senior Secured Loan One [Member] \| Maximum [Member] \| Measurement Input, EBITDA Multiple [Member]
Investment owned, measurement input	17.1	16.8
Valuation Technique, Price of Comparable Business [Member] \| Senior Secured Loan One [Member] \| Weighted Average [Member] \| Measurement Input, EBITDA Multiple [Member]
Investment owned, measurement input	9	9.6
Valuation Technique, Price of Comparable Business [Member] \| Senior Secured Loan Two [Member] \| Minimum [Member] \| Measurement Input, EBITDA Multiple [Member]
Investment owned, measurement input	4.7	7.2
Valuation Technique, Price of Comparable Business [Member] \| Senior Secured Loan Two [Member] \| Maximum [Member] \| Measurement Input, EBITDA Multiple [Member]
Investment owned, measurement input	8.3	10.3
Valuation Technique, Price of Comparable Business [Member] \| Senior Secured Loan Two [Member] \| Weighted Average [Member] \| Measurement Input, EBITDA Multiple [Member]
Investment owned, measurement input	7.4	9.3
Valuation Technique, Price of Comparable Business [Member] \| Senior Secured Loan Three [Member]
Long-term investments	$ 3,590	$ 3,807
Valuation Technique, Price of Comparable Business [Member] \| Senior Secured Loan Three [Member] \| Minimum [Member] \| Measurement Input, EBITDA Multiple [Member]
Investment owned, measurement input	5.9	6
Valuation Technique, Price of Comparable Business [Member] \| Senior Secured Loan Three [Member] \| Maximum [Member] \| Measurement Input, EBITDA Multiple [Member]
Investment owned, measurement input	7.3	7.5
Valuation Technique, Price of Comparable Business [Member] \| Senior Secured Loan Three [Member] \| Weighted Average [Member] \| Measurement Input, EBITDA Multiple [Member]
Investment owned, measurement input	6.8	6.6
Valuation Approach, Transactions Precedent [Member] \| Senior Secured Loan One [Member] \| Minimum [Member] \| Measurement Input, EBITDA Multiple [Member]
Investment owned, measurement input	6.4	6.4
Valuation Approach, Transactions Precedent [Member] \| Senior Secured Loan One [Member] \| Maximum [Member] \| Measurement Input, EBITDA Multiple [Member]
Investment owned, measurement input	18.9	18.9
Valuation Approach, Transactions Precedent [Member] \| Senior Secured Loan One [Member] \| Weighted Average [Member] \| Measurement Input, EBITDA Multiple [Member]
Investment owned, measurement input	10.9	10.8
Valuation Approach, Transactions Precedent [Member] \| Senior Secured Loan Two [Member] \| Minimum [Member] \| Measurement Input, EBITDA Multiple [Member]
Investment owned, measurement input	6.4	10
Valuation Approach, Transactions Precedent [Member] \| Senior Secured Loan Two [Member] \| Maximum [Member] \| Measurement Input, EBITDA Multiple [Member]
Investment owned, measurement input	13.5	13.7
Valuation Approach, Transactions Precedent [Member] \| Senior Secured Loan Two [Member] \| Weighted Average [Member] \| Measurement Input, EBITDA Multiple [Member]
Investment owned, measurement input	11.4	12.7
Valuation Approach, Transactions Precedent [Member] \| Senior Secured Loan Three [Member] \| Minimum [Member] \| Measurement Input, EBITDA Multiple [Member]
Investment owned, measurement input	6.3	8
Valuation Approach, Transactions Precedent [Member] \| Senior Secured Loan Three [Member] \| Maximum [Member] \| Measurement Input, EBITDA Multiple [Member]
Investment owned, measurement input	9.5	9.5
Valuation Approach, Transactions Precedent [Member] \| Senior Secured Loan Three [Member] \| Weighted Average [Member] \| Measurement Input, EBITDA Multiple [Member]
Investment owned, measurement input	8.1	8.6
Valuation Technique, Discounted Cash Flow [Member] \| Senior Secured Loan Two [Member] \| Minimum [Member] \| Measurement Input, Weighted Average Cost of Capital [Member]
Investment owned, measurement input	0.084	0.083
Valuation Technique, Discounted Cash Flow [Member] \| Senior Secured Loan Two [Member] \| Maximum [Member] \| Measurement Input, Weighted Average Cost of Capital [Member]
Investment owned, measurement input	0.098	0.101
Valuation Technique, Discounted Cash Flow [Member] \| Senior Secured Loan Two [Member] \| Weighted Average [Member] \| Measurement Input, Weighted Average Cost of Capital [Member]
Investment owned, measurement input	0.095	0.09
Valuation Technique, Discounted Cash Flow [Member] \| Senior Secured Loan Three [Member] \| Minimum [Member] \| Measurement Input, Weighted Average Cost of Capital [Member]
Investment owned, measurement input	0.091	0.091
Valuation Technique, Discounted Cash Flow [Member] \| Senior Secured Loan Three [Member] \| Maximum [Member] \| Measurement Input, Weighted Average Cost of Capital [Member]
Investment owned, measurement input	0.134	0.091
Valuation Technique, Discounted Cash Flow [Member] \| Senior Secured Loan Three [Member] \| Weighted Average [Member] \| Measurement Input, Weighted Average Cost of Capital [Member]
Investment owned, measurement input	0.103	0.091

Note 5 - Fair Value Measurements - Unobservable Inputs (Details) - Fair Value, Recurring [Member] - Fair Value, Inputs, Level 3 [Member]
$ in Thousands