Nature of Business (Details)		12 Months Ended
	Jul. 27, 2017 USD ($) $ / shares shares	Dec. 31, 2017 USD ($) Class Drug Candidate Patient $ / shares	Dec. 31, 2016 USD ($)	Dec. 16, 2016 $ / shares	Dec. 15, 2016 $ / shares	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Nature of Business [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]
Warrants exercise price (in dollars per share) | $ / shares		$ 30		$ 3.06	$ 4.20
Estimated Projected Expenditure Type [Line Items]
Cash and cash equivalents		$ 37,643,404	$ 56,959,485			$ 22,261,372	$ 32,218,905
Period for projected cash burn required to be maintained		3 months
Projected cash burn		$ 10,000,000
Projected expenditures for clinical programs		$ 27,800,000
Reserve stock split		6
Clinical Programs [Member]
Estimated Projected Expenditure Type [Line Items]
Projected expenditures for clinical programs		$ 1,500,000
Albumin-Binding Cancer Drugs [Member]
Estimated Projected Expenditure Type [Line Items]
Projected expenditures for clinical programs		3,100,000
General Operation [Member]
Estimated Projected Expenditure Type [Line Items]
Projected expenditures for clinical programs		700,000
Other General and Administrative Expenses [Member]
Estimated Projected Expenditure Type [Line Items]
Projected expenditures for clinical programs		10,100,000
Interest and Principal Payments [Member]
Estimated Projected Expenditure Type [Line Items]
Projected expenditures for clinical programs		$ 12,400,000
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