Accounting policy.

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- Definition

Offering expenses related to the entity's first offering of stock to the public.

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- Definition

Underwriting discounts and commissions related to the entity's first offering of stock to the public.

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No definition available.

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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- Definition

Amount of the related income tax effect of a cumulative effect on retained earnings.

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- Definition

Represents the quantification of the effect of adopting the new accounting standard or change in accounting principle expected by the entity to have a significant effect on the entity's financial statements.

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No definition available.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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- Definition

The cash inflow from the additional capital contribution to the entity.

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Per share or per unit amount of equity securities issued.

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No definition available.

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- Definition

Number of new stock issued during the period.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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Significant Accounting Policies - Additional Information (Detail)		3 Months Ended	6 Months Ended
	Apr. 11, 2017 USD ($) $ / shares shares	Jun. 30, 2016 shares	Jun. 30, 2017 USD ($) Segment	Jun. 30, 2016 USD ($)
Accounting Policy [Line Items]
Net proceeds from offering			$ 12,244,000	$ 4,496,000
Number of operating segment \| Segment			1
Anti-dilutive securities excluded from computation of diluted net income per share \| shares		6,600,000
ASU 2016-09 [Member]
Accounting Policy [Line Items]
Retrospective increase in deferred tax assets for previously unrecognized excess tax benefits			$ 19,500,000
Increase in valuation allowance			19,500,000
Net impact to accumulated deficit			$ 0
Follow-on Offering [Member]
Accounting Policy [Line Items]
Common stock shares sold \| shares	5,228,750
Public offering price \| $ / shares	$ 22.95
Net proceeds from offering	$ 115,100,000
Underwriting discounts and commissions	4,900,000
Offering expenses	$ 600,000