STOCKHOLDERS' EQUITY - Assumptions Used In Black-Scholes Model (Details) - $ / shares	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	41.00%	41.00%	44.00%
Expected dividend yield	0.00%	0.00%	0.00%
Risk-free interest rate, minimum	2.50%	1.80%	1.10%
Risk-free interest rate, maximum	3.00%	2.40%	2.20%
Weighted average expected term (in years)	4 years 5 months 18 days	4 years 9 months 18 days	4 years 10 months 24 days
Weighted average fair value of options granted (in dollars per share)	$ 8.19	$ 5.70	$ 5.74
Stock Purchase Right
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	41.00%	40.00%	37.00%
Expected dividend yield	0.00%	0.00%	0.00%
Risk-free interest rate	2.43%	1.33%	0.65%
Weighted average expected term (in years)	9 months 18 days	9 months 18 days	9 months 18 days
Weighted average fair value of options granted (in dollars per share)	$ 5.74	$ 4.10	$ 4.19

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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- Definition

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

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Paragraph 2
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