Addition In Reserve Equity Instruments Other Than Options Quantity Of Addition

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Cap on fair value of shares available for purchase by participants.

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Employee Stock Purchase Plan, Number of Shares Purchased by Employee

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Exercise price of options percentage of fair market value of common stock.

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Percentage of incentive stock option granted.

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Percentage of voting stock.

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Percentage of Annualized Forfeiture Rate For Award Granted

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Reduction In Reserve, Equity Instruments Other Than Options, Quantity Of Reduction

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Reduction In Reserve, Options, Quantity Of Reduction

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Term of options granted, years

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Aggregate number of common shares reserved for future issuance.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

Discount rate from fair value on offering date that participants pay for shares.

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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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The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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The highest quantity of shares an employee can purchase under the plan per period.

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Number of additional shares authorized for issuance under share-based payment arrangement.

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Number of shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Per share weighted-average price paid for shares purchased on open market for issuance under share-based payment arrangement.

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STOCK PLANS - Narrative (Details)					12 Months Ended
STOCK PLANS - Narrative (Details)	Sep. 10, 2020 shares	Sep. 12, 2019 shares	Nov. 08, 2018 shares	Mar. 01, 2012 USD ($) shares	Mar. 31, 2021 USD ($) $ / shares shares	Sep. 09, 2020	Mar. 31, 2020	Mar. 31, 2019	Sep. 07, 2011 shares
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost \| $					$ 94,800,000
Unrecognized cost, period for recognition, years					1 year 3 months 18 days
Employee stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares purchased by employees (in shares)					561,669
Shares issued under ESPP plan, weighted average purchase price per share (in dollars per share) \| $ / shares					$ 25.69
Shares available for future issuance under the ESPP (in shares)					1,751,813
Maximum \| Incentive options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of options granted, years					5 years
2011 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, equity awards reserved for issuance (in shares)									2,500,000
Number of additional shares available (in shares)			3,000,000
Maximum payroll deductions for purchase of shares by participants				20.00%
Maximum number of shares available for purchased by participants (in shares)				2,000
Cap on fair value of shares available for purchase by participants \| $				$ 25,000
Percentage of common stock price for employees				85.00%
2011 Employee Stock Purchase Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cap on fair value of shares available for purchase by participants \| $				$ 50,000
2019 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, equity awards reserved for issuance (in shares)		6,794,651
Number of additional shares available (in shares)	2,967,262	5,500,000
Minimum vesting requirement					4 years
Reduction for each share of common stock pursuant to other than option		1.00
Shares available for grant (in shares)					4,495,613
Percentage of incentive stock option granted					110.00%
2019 Equity Incentive Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of options granted, years					7 years
2019 Equity Incentive Plan \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of fair market value of common stock					100.00%
Percentage of voting stock					10.00%
2007 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional shares available (in shares)		1,294,651
2007 Equity Incentive Plan \| Independent Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of annualized forfeiture rate for awards granted					0.00%		0.00%	0.00%
2007 Equity Incentive Plan \| Senior Executives
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of annualized forfeiture rate for awards granted					2.00%		2.00%	2.00%
2007 Equity Incentive Plan \| Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of annualized forfeiture rate for awards granted					5.00%		5.00%	5.00%
2019 Amended, Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, equity awards reserved for issuance (in shares)	7,667,262
Number of additional shares available (in shares)	4,700,000
Minimum vesting requirement	1 year
Reduction for each share of common stock pursuant to other than option	2.32	2.76
Addition in reserve equity	2.32					2.76
Reduction for each share of common stock pursuant to option		1
Shares available for grant (in shares)					7,868,290