Common Stock, Additional Capital Shares Reserved for Future Issuance

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- Definition

Employee Stock Purchase Plan, Duration Of Offering Period

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Employee Stock Purchase Plan, Duration Of Purchase Period

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Employee Stock Purchase Plan, Percentage Of Market Value Price Of Common Stock

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Employee Stock Purchase Plan, Term of Extension

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- Definition

Aggregate number of common shares reserved for future issuance.

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-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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- 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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- Definition

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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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 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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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Aggregate change in value for stock issued during the period as a result of employee stock purchase plan.

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Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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STOCKHOLDERS' EQUITY - Narrative (Details) - USD ($)				1 Months Ended			12 Months Ended
STOCKHOLDERS' EQUITY - Narrative (Details) - USD ($)	Sep. 18, 2006	Jan. 01, 2005	Dec. 31, 2004	Aug. 31, 2017	May 31, 2017	May 31, 2006	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017	Aug. 31, 2018	Jun. 30, 2018	Jan. 31, 2018	Oct. 31, 2017	Oct. 31, 2016	Aug. 31, 2016	Oct. 31, 2015	Jul. 31, 2015	Nov. 30, 2014	Aug. 31, 2014	Sep. 30, 2013	Jun. 30, 2012	Jun. 30, 1996
2015 Repurchase Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock repurchase program, authorized amount														$ 15,000,000.0		$ 15,000,000.0
2017 Repurchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock repurchase program, authorized amount					$ 25,000,000
Stock repurchase program, remaining authorized repurchase amount							$ 7,100,000
2006 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for future issuance (in shares)						7,000,000
Vesting period							4 years
Expiration period							10 years
Number of shares available for future grant (in shares)							0
2012 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for future issuance (in shares)																					4,100,000
Vesting period							4 years
Expiration period							10 years
Number of shares available for future grant (in shares)							10,700,000
Number of additional shares reserved for future issuance (in shares)										16,300,000					4,500,000				6,800,000
2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for future issuance (in shares)																				1,000,000
Vesting period							4 years
Expiration period							10 years
Number of shares available for future grant (in shares)							0
Number of additional shares reserved for future issuance (in shares)																	1,200,000	1,200,000
2017 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for future issuance (in shares)													1,000,000
Vesting period							3 years
Expiration period							10 years
Number of shares available for future grant (in shares)							600,000
Number of additional shares reserved for future issuance (in shares)											1,500,000	1,500,000
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of options exercised							$ 10,000,000	$ 9,000,000	$ 7,200,000
Unamortized stock-based compensation expense							$ 107,000,000
Weighted average period of recognition for unrecognized compensation expense							2 years 3 months 18 days
Employee Stock \| Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for future issuance (in shares)							500,000															500,000
Unamortized stock-based compensation expense							$ 1,800,000
Weighted average period of recognition for unrecognized compensation expense							7 months 6 days
Term of extension	10 years			10 years	10 years	10 years
Value of shares issued under employee stock purchase plan							$ 500,000	$ 400,000	$ 300,000
Percentage of market value price of common stock under Employee Stock Purchase Plan							85.00%
Duration of offering period		1 year	2 years
Duration of purchase period			6 months
Maximum contribution percentage amount of employee's base compensation							10.00%