v3.23.2
Note 4 - Asset Acquisition (Details Textual) - USD ($)
$ / shares in Units, $ in Thousands
 12 Months Ended
Jan. 07, 2022
Dec. 31, 2022
In Process Research and Development [Member]    
Impairment of Intangible Assets, Indefinite-Lived (Excluding Goodwill)   $ 0
Lowell Therapeutics [Member]    
Business Combination, Consideration Transferred, Net of Cash Acquired $ 32,500  
Cash Acquired from Acquisition 3,549  
Business Combination, Options To Purchase Capital Stock Issued and Outstanding Cancelled, Exchange for Cash $ 3,500  
Business Combination, Acquiree Common Stock to Be Held Back to Satisfy Some Obligations (in shares) 69,808  
Business Combination, Acquiree Common Stock to Be Held Back to Satisfy Some Obligations, Value [1] $ 800  
Business Combination, Cash and Stock Paid for Transaction Costs 500  
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets, Total [2] 8,819  
Business Combination, Consideration Transferred, Total 12,368  
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable 6,000  
Business Combination, Acquisition Related Costs 500  
Payments to Acquire Businesses, Gross 3,536  
Business Acquisition, Transaction Costs 2,521  
Lowell Therapeutics [Member] | Contingent Consideration Payable Upon Achievement of Milestones [Member]    
Business Combination, Contingent Consideration, Liability, Total $ 26,000  
Lowell Therapeutics [Member] | AcelRx Common Stock [Member]    
Business Combination, Options To Purchase Capital Stock Issued and Outstanding Cancelled, Exchange for Common Stock, Number (in shares) 450,477  
Business Combination, Acquiree Common Stock to Be Held Back to Satisfy Some Obligations, Fixed Value per Share (in dollars per share) $ 11.46  
Business Combination, Options To Purchase Capital Stock Issued and Outstanding Cancelled, Exchange for Common Stock, Value $ 5,200  
Business Combination, Acquiree Common Stock to Be Held Back to Satisfy Some Obligations (in shares) 69,808  
Business Combination, Acquiree Common Stock to Be Held Back to Satisfy Some Obligations, Value $ 800  
[1] Recorded as Other long-term liabilities in the Condensed Consolidated Balance Sheets.
[2] Recorded as In-process research and development asset in the Condensed Consolidated Balance Sheets.