Note 12 - Subsequent Events	12 Months Ended
Dec. 31, 2022
Notes to Financial Statements
Subsequent Events [Text Block]	12. Subsequent Events Subsequent events have been evaluated through the date that the Company approved the consolidated financial statements. The following subsequent events have occurred during the period. Private Placement Offering Completion As described in Note 6, on February 28, 2023, the Company completed a private placement offering, raising gross proceeds of $9.2 million before deduction of estimated offering expenses of approximately $1.1 million. Of this amount, gross proceeds of $5.0 million were received in an initial closing in late December 2022 and a further $4.2 million in January and February 2023. A total of 3,216,805 shares of common stock and warrants to purchase 2,090,923 shares of common stock were issued after December 31, 2022 in connection with the subsequent closings held in January and February 2023. New Facility Occupancy The Company took occupancy of its new headquarters office building in February 2023. As of December 31, 2022, the Company owed the new landlord $2.5 million related to agreed-upon excess construction costs, deferral fees, and interest for the new facility as construction-in-progress. The Company remitted payment to the landlord for these costs in January 2023. The Company anticipates at least another $0.7 million of excess construction costs and related interest and deferral fees for which it will be responsible, and they will become due in the first half of 2023.

Note 12 - Subsequent Events

12 Months Ended

Dec. 31, 2022

12. Subsequent Events

Subsequent events have been evaluated through the date that the Company approved the consolidated financial statements. The following subsequent events have occurred during the period.

Private Placement Offering Completion

As described in Note 6, on February 28, 2023, the Company completed a private placement offering, raising gross proceeds of $9.2 million before deduction of estimated offering expenses of approximately $1.1 million. Of this amount, gross proceeds of $5.0 million were received in an initial closing in late December 2022 and a further $4.2 million in January and February 2023. A total of 3,216,805 shares of common stock and warrants to purchase 2,090,923 shares of common stock were issued after December 31, 2022 in connection with the subsequent closings held in January and February 2023.

New Facility Occupancy

The Company took occupancy of its new headquarters office building in February 2023. As of December 31, 2022, the Company owed the new landlord $2.5 million related to agreed-upon excess construction costs, deferral fees, and interest for the new facility as construction-in-progress. The Company remitted payment to the landlord for these costs in January 2023. The Company anticipates at least another $0.7 million of excess construction costs and related interest and deferral fees for which it will be responsible, and they will become due in the first half of 2023.