Computation of Net Loss per Common Share - Reconciliation of Numerators and Denominators of EPS Calculation (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Jun. 30, 2017	Jun. 30, 2016
Numerator:
Net loss	$ (15,252)	$ (10,355)
Denominator:
Weighted-average shares of common stock outstanding (in shares)	17,089	14,132
Weighted-average shares subject to repurchase (in shares)	(311)	(456)
Shares used in per-share calculation ― basic (in shares)	16,778	13,676
Shares used in per-share calculation ― diluted (in shares)	16,778	13,676
Net loss per share ― basic (in dollars per share)	$ (0.91)	$ (0.76)
Net loss per share ― diluted (in dollars per share)	$ (0.91)	$ (0.76)

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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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.

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Number of shares of common stock subject to repurchase or cancellation determined by relating the portion of time within a reporting period that these shares have been outstanding to the total time in that period. Common stock subject to repurchase are outstanding common shares that are contingently returnable (that is, subject to recall).

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This element represents the weighted average total number of shares issued throughout the period including the first (beginning balance outstanding) and last (ending balance outstanding) day of the period before considering any reductions (for instance, shares held in treasury) to arrive at the weighted average number of shares outstanding. Weighted average relates to the portion of time within a reporting period that common shares have been issued and outstanding to the total time in that period. Such concept is used in determining the weighted average number of shares outstanding for purposes of calculating earnings per share (basic).

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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.

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