Stock-based Compenstaion Assumptions Used In Black-Scholes Model (Details) - $ / shares	3 Months Ended	9 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Option Grants and Stock Purchase Rights
Expected volatility	42.00%	51.00%	44.00%	53.00%
Expected dividend yield	0.00%	0.00%	0.00%	0.00%
Risk-free interest rate	1.20%	1.75%	1.17%	1.60%
Weighted average expected option term, in years	4 years 180 days	5 years 90 days	4 years 248 days	5 years 158 days
Weighted average fair value of options granted, per share	$ 5.54	$ 4.92	$ 5.47	$ 4.12
Employee Stock Purchase Plan Rights
Expected volatility	0.00%	0.00%	40.00%	45.00%
Expected dividend yield	0.00%	0.00%	0.00%	0.00%
Risk-free interest rate	0.00%	0.00%	0.45%	0.30%
Weighted average expected option term, in years	0 years	0 years	274 days	9 months
Weighted average fair value of options granted, per share	$ 0.00	$ 0.00	$ 4.04	$ 2.78

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

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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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