Goodwill and Intangible Assets - Schedule of Changes in Carrying Amounts of IPR&D Assets and Goodwill (Detail) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2017
Indefinite-lived Intangible Assets [Line Items]
Goodwill Balance, beginning of period		$ 18,758,421
Goodwill, Additions from the Mergers		15,573,822
Goodwill, Foreign currency translation adjustments		1,602,661
Goodwill, Impairment charges	$ (26,600,000)	(26,600,000)
Goodwill Balance, end of period	9,334,904	9,334,904
IPR&D [Member]
Indefinite-lived Intangible Assets [Line Items]
IPR&D Balance, beginning of period		14,477,019
IPR&D, Additions from the Mergers		22,389,000
IPR&D, Foreign currency translation adjustments		1,235,457
IPR&D Balance, end of period	$ 38,101,476	$ 38,101,476

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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