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Exercise Price As Percentage Of Fair Market Value On Grant Date, Minimum

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Number of Purchase Period in Each Offering Period

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- Definition

Number of Stock-based Compensation Plans

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- Definition

Purchase Price as Percentage of Lower of Fair Market Value on First Day of Offering Period or Purchase Date.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

Aggregate number of common shares reserved for future issuance.

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- Definition

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

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

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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Number of shares issued under share-based payment arrangement.

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- Definition

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

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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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STOCK PLANS AND SHARE BASED COMPENSATION (Details) $ in Thousands, shares in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) period plan shares	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock-based compensation plans \| plan	3
Number of shares available for future issuance	3.4
Stock-based compensation expense \| $	$ 30,912	$ 23,347	$ 21,580
2016 Incentive Award Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period	2.2
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	2.8
Incentive Stock Options [Member] \| 2007 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price of stock options as percentage of fair market value on date of grant, minimum	100.00%
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period	4 years
Stock-based compensation expense \| $	$ 18,700	17,500	16,600
Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum percentage of employee's compensation eligible for payroll deductions	15.00%
Purchase price of the purchase plan as percentage of the lower of the fair market value on the first day of each offering period or on the purchase date	85.00%
Number of purchase periods in each offering period \| period	1
Duration of each purchase period in each offering period	6 months
Shares reserved for issuance	7.0
Number of shares purchased	6.6
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	0.4
Stock-based compensation expense \| $	$ 2,000	$ 1,700	$ 1,600
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period	4 years
Stock Options [Member] \| 2007 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period	48 months
Stock Options [Member] \| 2007 Equity Incentive Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards expiration period	10 years