Description of Company and Basis of Presentation (Details)			3 Months Ended
	Oct. 03, 2017 USD ($)	Jul. 27, 2017 USD ($) $ / shares shares	Mar. 31, 2018 USD ($) Class Drug Candidate Patient	Dec. 31, 2017 USD ($)
Description of Company and Basis of Presentation [Abstract]
Number of classes of ultra-high potency drug conjugates | Class			2
Number of designed drug conjugates with highly potent cytotoxic payloads | Drug			75
Number of distinct classes of compound | Class			2
Number of lead candidates | Candidate			4
Number of patients tested for various types of cancer | Patient			600
Number of years Orphan Drug Designation provides several benefits of market exclusivity after approval			7 years
Number of years soft tissue sarcomas confers market among other benefits			10 years
Schedule of Strategic Investment Agreement [Line Items]
Deferred revenue			$ 0	$ 6,924,353
NantCell, Inc [Member]
Schedule of Strategic Investment Agreement [Line Items]
Net proceeds received from the sale of common stock		$ 13,000,000
Common stock, share price (in dollars per share) | $ / shares		$ 6.60
Percentage of common stock premium at market price		92.00%
Warrants to purchase shares of common stock (in shares) | shares		500,000
Warrants exercise price (in dollars per share) | $ / shares		$ 6.60
Period to purchase common stock by exercising warrants			18 months
NantCell, Inc [Member] | Maximum [Member]
Schedule of Strategic Investment Agreement [Line Items]
Fee contingent payments entitled to be received under license agreement		$ 343,000,000
Deferred revenue	$ 4,200,000
Anticipated reimbursement	$ 3,200,000