Note 5 - Investments - Investments (Details) - USD ($) $ in Thousands |
Sep. 30, 2020 |
Dec. 31, 2019 |
|---|---|---|
| Investment, Cost | $ 32,996 | $ 17,740 |
| Investment, Unrealized gain/(loss) | 1 | 18 |
| Investment, Market value | 32,997 | 17,758 |
| Corporate Debt Securities [Member] | ||
| Investment, Cost | 8,999 | 3,736 |
| Investment, Unrealized gain/(loss) | 1 | |
| Investment, Market value | 9,000 | 3,736 |
| Investments [Member] | ||
| Investment, Cost | 12,008 | |
| Investment, Unrealized gain/(loss) | 18 | |
| Investment, Market value | 12,026 | |
| US Treasury Securities [Member] | ||
| Investment, Cost | 23,997 | |
| Investment, Unrealized gain/(loss) | ||
| Investment, Market value | $ 23,997 | |
| Canadian Provincial Promissory Notes [Member] | ||
| Investment, Cost | 1,996 | |
| Investment, Unrealized gain/(loss) | ||
| Investment, Market value | $ 1,996 |
| X | ||||||||||
- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, before tax, of unrealized gain (loss) in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). No definition available.
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