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Note 4 - Collaboration Revenue (Details Textual) $ / shares in Units, ¥ in Billions |  |  |  | 1 Months Ended | 12 Months Ended | 31 Months Ended |
--- | --- | --- | --- | --- | --- | --- | ---
Jun. 13, 2022 USD ($) shares | Nov. 20, 2020 USD ($) | Nov. 12, 2020 $ / shares shares | Jun. 30, 2022 USD ($) shares | Nov. 30, 2020 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Nov. 12, 2022 USD ($) $ / shares shares | Sep. 30, 2021 USD ($) | Sep. 30, 2021 CNY (¥)
Revenue from Contract with Customer, Including Assessed Tax |  |  |  |  |  | $ 1,751,000 | $ 1,351,000 | $ 1,351,000 |  |  |  |
Dalian Wanchunbulin Pharmaceuticals Ltd. (“Wanchunbulin”) [Member] | Jiangsu Hengrui Pharmaceuticals Co., Ltd. [Member] |  |  |  |  |  |  |  |  |  |  |  |
Collaboration Agreement, Upfront Cash Payment |  |  |  |  |  |  |  |  |  |  | $ 31,039,000 | ¥ 0.2
Research Collaboration and License Agreement with Eli Lilly [Member] | Series A-2 Preferred Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |
Redeemable Noncontrolling Interest, Equity, Preferred, Fair Value | $ 3,763,000 |  |  |  |  |  |  |  | $ 5,267,000 |  |  |
Research Collaboration and License Agreement with Eli Lilly [Member] | SEED Therapeutics Inc. [Member] |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangement, Upfront Cash Payment |  | $ 9,455,000 |  |  | $ 10,000,000 |  |  |  |  |  |  |
Revenue from Collaborative Arrangement, Excluding Revenue from Contract with Customer |  |  |  |  |  | 2,000,000 |  |  |  |  |  |
Derivative Liability, Total | $ 1,237,000 |  |  |  |  |  |  |  | 278,000 |  |  |
Proceeds from Issuance or Sale of Equity, Total |  | $ 15,000,000 |  |  |  |  |  |  | $ 15,000,000 |  |  |
Revenue from Contract with Customer, Including Assessed Tax |  |  |  |  |  | 1,751,000 | 1,351,000 |  |  |  |  |
Collaboration Agreement,, Maximum Regulatory Development Milestones to be Received |  |  |  |  |  |  |  |  |  |  | 108,638,000 | 0.7
Collaboration Agreement, Maximum Commercial Milestones to be Received |  |  |  |  |  |  |  |  |  |  | $ 62,079,000 | ¥ 0.4
Revenue from Contract with Customer, Excluding Assessed Tax |  |  |  |  |  | $ 0 | $ 0 | $ 0 |  |  |  |
Research Collaboration and License Agreement with Eli Lilly [Member] | SEED Therapeutics Inc. [Member] | Series A-1 Convertible Preferred Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued for Transfer of Assets, Shares (in shares) | shares |  |  | 9,631,941 |  |  |  |  |  |  |  |  |
Research Collaboration and License Agreement with Eli Lilly [Member] | SEED Therapeutics Inc. [Member] | Series A-1 Preferred Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues (in shares) | shares |  |  | 1,194,030 |  |  |  |  |  |  |  |  |
Research Collaboration and License Agreement with Eli Lilly [Member] | SEED Therapeutics Inc. [Member] | Series A-2 Preferred Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues (in shares) | shares | 1,990,000 |  | 1,990,000 | 1,990,000 |  |  |  |  |  |  |  |
Shares Issued, Price Per Share (in dollars per share) | $ / shares |  |  | $ 2.5125 |  |  |  |  |  |  |  |  |
Stock Issued During Period, Value, New Issues | $ 5,000,000 |  |  | $ 5,000,000 |  |  |  |  |  |  |  |
Research Collaboration and License Agreement with Eli Lilly [Member] | SEED Therapeutics Inc. [Member] | Additional Series A-2 Preferred Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues (in shares) | shares |  |  |  |  |  |  |  |  |  | 1,990,000 |  |
Shares Issued, Price Per Share (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  |  | $ 2.5125 |  |
Stock Issued During Period, Value, New Issues |  |  |  |  |  |  |  |  |  | $ 1,990,000 |  |
Research Collaboration and License Agreement with Eli Lilly [Member] | SEED Therapeutics Inc. [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangement, Equity Investment |  |  |  |  | $ 780,000,000 |  |  |  |  |  |  |

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