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NanoTx License Agreement - Additional Information (Details) - USD ($)	May 07, 2020	Dec. 31, 2020	Dec. 31, 2019
Common stock, shares issued (in shares)		6,749,028	3,880,588
Common stock, $0.001 par value; 100,000,000 shares authorized; 6,749,028 and 3,880,588 shares issued and outstanding in 2020 and 2019, respectively		$ 7,000	$ 4,000
Nano Tx Licenses Agreement [Member]
License fee payment in cash	$ 400,000
Common stock, shares issued (in shares)	230,769
Common stock, $0.001 par value; 100,000,000 shares authorized; 6,749,028 and 3,880,588 shares issued and outstanding in 2020 and 2019, respectively	$ 781,000
Nano Tx Licenses Agreement [Member] | Development And Sales Milestone [Member]
Milestone payments	$ 136,500,000

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-Publisher FASB
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