Income Taxes - Summary of Changes in Amount of Unrecognized Tax Benefits (Excluding Interest and Penalties) (Detail)	12 Months Ended
Dec. 31, 2016 USD ($)
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Additions based on tax positions of prior years	$ 1,961,595
Ending balance of unrecognized tax benefits	$ 1,961,595

Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration