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Licenses Acquired (Oncogenuity and Tamid - Narrative) (Details)		12 Months Ended
	May 06, 2020 USD ($) shares	Dec. 31, 2020 USD ($) $ / shares	Dec. 31, 2019 USD ($)
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development - licenses acquired		$ 2,834,000	$ 6,090,000
Oncogenuity [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development - licenses acquired		271,000	0
Licensing Agreements [Member] \| Oncogenuity [Member] \| Columbia University [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Upfront fees payment	$ 300,000
Common shares issued (in shares) \| shares	1,000,000
Amount of net of debt utilized		21,000
Research and development - licenses acquired		300,000
Licensing Agreements [Member] \| Tamid [Member] \| University of North Carolina [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development - licenses acquired		$ 0	$ 0
Licensing Agreements [Member] \| Discount for Lack of Marketability [Member] \| Oncogenuity [Member] \| Columbia University [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Common Shares, measurement input			0.417
Licensing Agreements [Member] \| Measurement Input Weighted Average Cost of Capital [ Member] \| Oncogenuity [Member] \| Columbia University [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Common Shares, measurement input			0.205
Licensing Agreements [Member] \| Share Price [Member] \| Oncogenuity [Member] \| Columbia University [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Common Shares, measurement input \| $ / shares		0.021
Licensing Agreements [Member] \| Completion of Clinical Development Milestones [Member] \| Oncogenuity [Member] \| Columbia University [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Payments of milestones	$ 15,300,000
Licensing Agreements [Member] \| Achievement of Certain Sales Milestones [Member] \| Oncogenuity [Member] \| Columbia University [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Payments of milestones	15,000,000.0
Licensing Agreements [Member] \| Certain Milestones in Connection with the Initial Indication [Member] \| Oncogenuity [Member] \| Columbia University [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Payments of milestones	$ 18,000,000.0
Oncogenuity [Member] \| Licensing Agreements [Member] \| Oncogenuity [Member] \| Columbia University [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Percentage of ownership	10.00%