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NanoTx License Agreement - Additional Information (Details) - USD ($)	May 07, 2020	Sep. 30, 2020	Dec. 31, 2019
Common stock, shares issued (in shares)		4,591,415	3,880,588
Common stock, $0.001 par value; 100,000,000 shares authorized; 4,591,415 and 3,880,588 shares issued and outstanding at September 30, 2020 and December 31, 2019, respectively		$ 5,000	$ 4,000
NanoTx License 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; 4,591,415 and 3,880,588 shares issued and outstanding at September 30, 2020 and December 31, 2019, respectively	$ 781,000
NanoTx License Agreement [Member] | Development and Sales Milestone [Member]
Milestone payments	$ 136,500,000

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