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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- Definition

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

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- Definition

Percentage of incentive stock option granted.

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Percentage of voting stock.

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- Definition

Percentage of Annualized Forfeiture Rate For Award Granted

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- Definition

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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- Definition

Restricted stock shares issued net of shares for tax withholdings restoration ratio

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- Definition

Share based compensation arrangement by share based payment award equity outstanding.

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- Definition

Term of options granted, years

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

Unrecognized cost of unvested share-based compensation awards.

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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

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

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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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- Definition

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

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- Definition

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

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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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- Definition

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

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The weighted average of per share prices paid for shares purchased on the open market for issuance to employees under the plan.

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STOCK PLANS - Narrative (Details)		1 Months Ended	12 Months Ended
STOCK PLANS - Narrative (Details)	Sep. 07, 2011 USD ($) shares	Sep. 30, 2007 shares	Mar. 31, 2017 USD ($) $ / shares shares	Mar. 31, 2016 shares	Mar. 31, 2015 shares	Sep. 22, 2015 shares	Mar. 31, 2014 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)			0	0	0		31,350
Employee stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares purchased by employees			471,658
Shares issued under ESPP plan, weighted average purchase price per share (in dollars per share) \| $ / shares			$ 33.28
Shares available for future issuance under the ESPP			1,096,090
Incentive options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of options granted, years			5 years
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost \| $			$ 0
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost \| $			$ 87,200,000
Unrecognized cost, period for recognition, years			1 year 8 months 4 days
2011 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, equity awards reserved for issuance	2,500,000
Maximum payroll deductions for purchase of shares by participants	20.00%
Maximum number of shares available for purchased by participants	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
1999 Stock Option And Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)			0
Shares available for grant			0
2007 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, equity awards reserved for issuance	21,500,000
Shares available for grant			8,602,261
Restoration ratio of restricted stock unit grants withheld		2
Reduction for each share of common stock pursuant to option		1
Reduction for each share of common stock pursuant to other than option		2
Equity awards outstanding			3,610,301
Share-based awards generally vest, years			4 years
Percentage of incentive stock option granted			110.00%
2007 Equity Incentive Plan \| Common stock voting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, equity awards reserved for issuance	8,000,000					8,500,000
2007 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 \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of options granted, years			10 years
Independent Directors \| 2007 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of incentive stock option granted				0.00%	0.00%
Percentage of annualized forfeiture rate for awards granted			0.00%
Employees \| 2007 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of incentive stock option granted				5.00%	5.00%
Percentage of annualized forfeiture rate for awards granted			5.00%
Senior Executives \| 2007 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of incentive stock option granted				2.00%	2.00%
Percentage of annualized forfeiture rate for awards granted			2.00%