Stockholder's Equity Assumptions Used In Black-Scholes Model (Details) - $ / shares	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Option Grants
Expected volatility	41.00%	44.00%	53.00%
Expected dividend yield	0.00%	0.00%	0.00%
Risk-free interest rate, minimum	1.80%	1.10%	1.50%
Risk-free interest rate, maximum	2.40%	2.20%	1.80%
Weighted average expected option term, in years	4 years 288 days	4 years 324 days	5 years 144 days
Weighted average fair value of options granted, per share	$ 5.70	$ 5.74	$ 4.17
Employee Stock Purchase
Expected volatility	40.00%	37.00%	43.00%
Expected dividend yield	0.00%	0.00%	0.00%
Risk-free interest rate	1.33%	0.65%	0.39%
Weighted average expected option term, in years	288 days	288 days	288 days
Weighted average fair value of options granted, per share	$ 4.10	$ 4.19	$ 3.25

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

The maximum risk-free interest rate assumption that is used in valuing an option on its own shares.

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No definition available.

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The minimum risk-free interest rate assumption that is used in valuing an option on its own shares.

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No definition available.

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- Definition

Weighted average expected volatility rate of share-based compensation awards.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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