Note 6 - Fair Value - Assets at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Fair Value, Recurring [Member]
Investments, fair value	$ 647,244	$ 697,891
Fair Value, Recurring [Member] \| Debt [Member]
Investments, fair value	596,025	638,779
Fair Value, Recurring [Member] \| Warrant [Member]
Investments, fair value	16,648	18,277
Fair Value, Recurring [Member] \| Other Investments [Member]
Investments, fair value	3,444	14,637
Fair Value, Recurring [Member] \| Equity Securities [Member]
Investments, fair value	31,127	26,198
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Investments, fair value	3,988	587
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Debt [Member]
Investments, fair value	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Warrant [Member]
Investments, fair value	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Other Investments [Member]
Investments, fair value	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Equity Securities [Member]
Investments, fair value	3,988	587
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Investments, fair value	1,916	1,839
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Debt [Member]
Investments, fair value	0	0
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Warrant [Member]
Investments, fair value	1,916	1,839
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Other Investments [Member]
Investments, fair value	0	0
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Equity Securities [Member]
Investments, fair value	0	0
Fair Value, Inputs, Level 3 [Member]
Investments, fair value	641,340	695,465
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Investments, fair value	641,340	695,465
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| Debt [Member]
Investments, fair value	596,025	638,779
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| Warrant [Member]
Investments, fair value	14,732	16,438
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| Other Investments [Member]
Investments, fair value	3,444	14,637
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| Equity Securities [Member]
Investments, fair value	$ 27,139	$ 25,611

- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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