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Acquisition of EGEN Assets (Details Narrative) - USD ($)					1 Months Ended	3 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2016	Jun. 20, 2014	Jun. 20, 2014	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Asset impairment charges, total						$ 2,400,000
Business Combination, Consideration Transferred, Liabilities Incurred								$ 4,500,000	$ 2,500,000
Finite-lived intangible assets, net, ending balance						511,463	$ 738,779	568,292	795,608
Purchase Agreement [Member]
Finite-lived intangible assets, net, ending balance						511,463		568,292
Finite-lived intangible assets, accumulated amortization						1,079,751		1,022,922
IPR&D Drug Technology Platforms [Member]
Asset impairment charges, total			$ 1,400,000
EGEN Inc [Member]
Potential future earn-out payments				$ 30,400,000	$ 30,400,000
Payments to Acquire Businesses, Gross					$ 3,000,000
Stock issued during period, shares, acquisitions					241,590
Business Combination, Consideration Transferred, Liabilities Incurred				13,900,000			12,800,000	$ 8,900,000	$ 12,500,000
Goodwill, acquisition						2,000,000
EGEN Inc [Member] \| Purchase Agreement [Member]
Finite-lived intangible assets acquired						$ 1,600,000
Finite-lived intangible asset, useful life						7 years
Amortization expense						$ 56,829	$ 56,829
EGEN Inc [Member] \| Glioblastoma Multiforme Brain Cancer [Member]
Asset impairment charges, total	$ 9,400,000	$ 9,400,000
EGEN Inc [Member] \| Ovarian Cancer [Member]
Finite-lived intangible assets, net, ending balance						13,300,000
EGEN Inc [Member] \| IPR&D Drug Technology Platforms [Member]
Indefinite lived intangible assets						$ 24,200,000
EGEN Inc [Member] \| Maximum [Member]
Total purchase price for the asset acquisition					$ 44,400,000
Potential future earn-out payments				$ 30,400,000	$ 30,400,000