Quarterly report pursuant to Section 13 or 15(d)

Equity (Details Textual)

Equity (Details Textual) - USD ($)
$ / shares in Units, $ in Thousands
1 Months Ended 3 Months Ended
Jun. 30, 2020
Jun. 19, 2020
Apr. 30, 2020
Apr. 24, 2020
Oct. 31, 2018
Mar. 31, 2020
Mar. 31, 2019
Equity (Textual)              
Received amount           $ 9,300 $ 900
Net proceeds on sale of common stock           $ 2,500 400
Share cancelled due to termination of employees           300  
Total option expense           $ 400 300
Unrecognized compensation expense           1,700  
Net proceeds on exercise of warrants           $ 1,504
Weighted average remaining contractual term           3 years 3 years
Subsequent Event [Member]              
Equity (Textual)              
Description of pre-funded warrants Holders of 36.0 million pre-funded warrants exercised their warrants at $0.0001 per share and received 36.0 million common shares.            
Subsequent event, description The Company issued 157 thousand restricted common shares for consulting services.   The Company sold 171 thousand common shares through its at-the-market program and realized net proceeds of $35 thousand. The Company issued and sold 128.3 million shares of common stock and 82.5 million pre-funded warrants to purchase shares of common stock. The price to the public in this offering for each share of common stock was $0.15 and for each pre-funded warrant was $0.1499. Each pre-funded warrant has an exercise price of $0.0001 per share and is exercisable immediately upon issuance. The warrants are subject to certain limitations on beneficial ownership. Gross proceeds from this offering to Actinium were $31.6 million, before deducting underwriting discounts and commissions and other offering expenses payable by the Company. Net proceeds from this offering were $29.1 million.      
Series A warrants [Member]              
Equity (Textual)              
Received amount             $ 1,500
Warrants exercised             2,500
Lincoln Park Capital Fund, LLC [Member]              
Equity (Textual)              
Received amount           $ 200  
Sale of common stock, shares           800,000  
Lincoln Park Capital Fund, LLC [Member] | Purchase Agreement [Member]              
Equity (Textual)              
Aggregate value of common stock, shares over life of agreement         $ 32,500    
Forecast [Member]              
Equity (Textual)              
Issuance of common stock, shares   55,700,000          
Warrant to purchase of common stock   21,300,000          
Warrants exercised   0.0001          
Net proceeds of public offering   $ 22,800          
Gross proceeds   $ 25,000          
Common Stock [Member]              
Equity (Textual)              
Issuance of common stock, shares           10,138,369 924,500
Common Stock [Member] | Forecast [Member]              
Equity (Textual)              
Share price   $ 0.325          
Warrant [Member] | Forecast [Member]              
Equity (Textual)              
Share price   $ 0.3249