Note 8 - Liability Related to Sale of Future Royalties - Activity of Liability Related to Sale of Future Royalties (Details) - USD ($) $ in Thousands |
1 Months Ended | 3 Months Ended | 6 Months Ended | 45 Months Ended | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
Sep. 30, 2015 |
Jun. 30, 2019 |
Jun. 30, 2018 |
Jun. 30, 2019 |
Jun. 30, 2018 |
Jun. 30, 2019 |
Dec. 31, 2018 |
[1] | |||
| Liability related to sale of future royalties — beginning balance | $ 93,679 | |||||||||
| Proceeds from sale of future royalties | $ 61,200 | 61,184 | ||||||||
| Non-cash royalty revenue | (161) | (538) | ||||||||
| Non-cash interest expense recognized | $ (996) | $ 2,995 | 611 | $ 5,811 | 33,483 | |||||
| Liability related to sale of future royalties as of June 30, 2019 | 94,129 | 94,129 | 94,129 | |||||||
| Less: current portion | (592) | (592) | (592) | $ (392) | ||||||
| Liability related to sale of future royalties — net of current portion | $ 93,537 | $ 93,537 | $ 93,537 | $ 93,287 | ||||||
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