Subsequent Events - Additional Information (Detail) - Subsequent Events - Underwritten Public Offering $ / shares in Units, $ in Millions	Jan. 22, 2018 USD ($) $ / shares shares
Subsequent Event [Line Items]
Common stock shares sold \| shares	11,500,000
Public offering price per share \| $ / shares	$ 5.25
Net proceeds, after deducting underwriting commissions and discounts and offering expenses payable \| $	$ 56.7

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

No definition available.

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