Income Taxes - Components of Deferred Tax Assets and Liabilities (Detail) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets:
Domestic NOLs	$ 4,025,587	$ 6,320,893
Foreign NOLs	5,303,154	8,323,454
Accrued expenses	162,814	19,597
Amortization	1,035,765	1,187,512
Deferred revenue	38,494	49,373
Stock compensation	568,165	589,986
Deferred rent	336,070	110,731
Depreciation		6,955
Research and development carryforward	73,156
Total deferred tax assets	11,543,205	16,608,501
Deferred tax liabilities:
IPR&D assets	(2,557,085)	(8,856,561)
Depreciation	(205,859)
IRC §481(a) adjustment		(20,118)
Total deferred tax liabilities	(2,762,944)	(8,876,679)
Deferred tax assets, net	8,780,261	7,731,822
Valuation allowance	(8,838,761)	(13,670,224)
Total deferred tax liabilities net	$ (58,500)	$ (5,938,402)