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Net (Loss) Income Per Share - Additional Information (Detail) - shares	Sep. 26, 2016	Jun. 15, 2016	Apr. 14, 2016	Dec. 31, 2016	Dec. 31, 2015
Schedule of Net Income (Loss) Per Share [Line Items]
Preferred stock issued pursuant to Private Placement			4,630,145
Preferred stock issued pursuant to Subsequent Financing		4,630,145
Preferred stock, shares outstanding				0	0
Public Offering [Member]
Schedule of Net Income (Loss) Per Share [Line Items]
Common stock shares issued	2,250,000

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Topic 210
-SubTopic 10
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Number of new stock issued during the period.

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