Net Loss per Share of Common Stock - Summary of Computation of Basic and Diluted Net Loss Per Share (Parenthetical) (Detail)	Oct. 16, 2018
Subsequent Event [Member]
Reverse stock split ratio	0.1667

Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB TOPIC 4.C)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770

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Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration