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NanoTx License Agreement - Additional Information (Details) - USD ($)	May 07, 2020	Sep. 30, 2021	Dec. 31, 2020
Common stock, shares issued (in shares)		15,360,025	6,749,028
Common stock, $0.001 par value; 100,000,000 shares authorized; 15,360,025 and 6,749,028 shares issued and outstanding at September 30, 2021 and December 31, 2020, respectively	$ 781,000	$ 15,000	$ 7,000
Nano Tx Licenses Agreement [Member]
License fee payment in cash	$ 400,000
Common stock, shares issued (in shares)	230,769
Nano Tx Licenses Agreement [Member] | Development And Sales Milestone [Member]
Milestone payments	$ 136,500,000

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