Note 10 - Investments in Marketable Securities (Details Textual) - USD ($) |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
Dec. 31, 2025 |
|
| Equity Securities Fv Ni Gross Unrealized Gain | $ 129,818,000 | $ 129,818,000 | $ 137,436,000 | ||
| Equity Securities Fv Ni Gross Unrealized Loss | 540,000 | 540,000 | 547,000 | ||
| Equity Securities, FV-NI, Unrealized Gain (Loss) | (17,599,000) | $ 20,827,000 | (7,610,000) | $ 26,748,000 | |
| Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax | 10,000 | 10,000 | 1,464,000 | ||
| Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax | $ 5,498,000 | 5,498,000 | $ 2,181,000 | ||
| Proceeds from Sale and Maturity of Marketable Securities | 22,683,000 | 64,689,000 | |||
| Debt Securities, Realized Gain (Loss) | $ 1,023,000 | $ 872,000 | |||