Net Loss per Share - Computation of Denominators Used in Net Loss per Share (Detail) - shares	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Basic:
Weighted average common shares outstanding	39,552,277	32,681,661
Diluted:
Weighted average common shares outstanding - Basic	39,552,277	32,681,661
Common stock options	0	0
Denominator for diluted net loss per share	39,552,277	32,681,661

No definition available.

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- References

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
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- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

+ References

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- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
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