Net Income (Loss) Per Common Share - Schedule of Potential Dilutive Common Shares (Parenthetical) (Detail)	Mar. 31, 2018 $ / shares
Series B Redeemable Convertible Preferred Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Preferred stock conversion price per share	$ 1.35

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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