Stockholders' Equity Option Activity (Details) - $ / shares	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Stockholders Equity Option Activity Details
Balance at beginning of period	4,462,412	4,793,266	5,327,907
Granted	609,135	407,392	723,776
Exercised	(773,897)	(603,998)	(1,162,175)
Cancelled/forfeited	(299,365)	(134,248)	(96,242)
Balance at end of period	3,998,285	4,462,412	4,793,266
Options, Vested and expected to vest	3,998,285
Options, Exercisable at end of period	3,025,925
Weighted-average exercise price of options outstanding, at beginning of period	$ 7.52	$ 6.29	$ 5.19
Weighted-average exercise price of options granted during period	14.95	14.63	8.63
Weighted-average exercise price of options exercised during the period	3.95	2.34	2.56
Weighted-average exercise price of options forfeited, cancelled or expired during the period	13.05	8.41	8.06
Weighted-average exercise price of options outstanding at end of period	8.93	$ 7.52	$ 6.29
Options, Vested and Expected to Vest, Weighted Average Exercise Price	7.52
Weighted-Average Exercise Prices, Exercisable at end of period	$ 7.66

No definition available.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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Net number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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