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

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Factor used to determine number of options units to be granted

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Number of Performance Based Awards Shares Released as Percentage of Target Number, Maximum

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Number of Performance Based Awards Shares Released as Percentage of Target Number, Minimum

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Number of Purchase Period in Each Offering Period

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Number of Stock-based Compensation Plans

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Reduction in Number of Shares Available for Issuance per Awards Unit Granted

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Share-Based Compensation Arrangement By Share Based Payment Award Employee Shares Purchased For Awards

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Aggregate number of common shares reserved for future issuance.

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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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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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 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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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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Purchase price of common stock expressed as a percentage of its fair value.

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STOCK PLANS AND SHARE-BASED COMPENSATION (Details)	3 Months Ended		6 Months Ended
STOCK PLANS AND SHARE-BASED COMPENSATION (Details)	Jun. 30, 2015 USD ($) $ / shares shares	Jun. 30, 2014 USD ($) $ / shares	Jun. 30, 2015 USD ($) Plan PurchasePeriod $ / shares shares	Jun. 30, 2014 USD ($) $ / shares	Dec. 31, 2014 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock-based compensation plans \| Plan			2
Awards expiration period, maximum (in years)			10 years
Allocated stock-based compensation expense \| $	$ 3,750,000	$ 4,175,000	$ 8,141,000	$ 8,090,000
Equity Incentive Plan 2007 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for future issuance	6,338,020		6,338,020
Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for future issuance	252,216		252,216
Maximum percentage of employee's compensation eligible for payroll deductions	15.00%		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%
Shares reserved for issuance	3,000,000		3,000,000
Employee shares purchased under employee stock purchase plan	2,747,784		2,747,784
Allocated stock-based compensation expense \| $	$ 300,000	300,000	$ 600,000	600,000
Number of purchase period in each offering period \| PurchasePeriod			1
Duration of each purchase period in each offering period			6 months
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			4 years
Allocated stock-based compensation expense \| $	$ 3,100,000	$ 2,700,000	$ 6,300,000	$ 5,200,000
Reduction in number of shares available for issuance under the 2007 Plan per award granted			2
Granted shares			282,000
Vested shares			248,000
Outstanding shares	707,000		707,000		692,000
Weighted-average grant date fair value per granted share \| $ / shares	$ 49.37	$ 47.81	$ 50.43	$ 50.97
Grant date fair value of awards released \| $	$ 7,800,000	$ 7,800,000	$ 10,600,000	$ 9,500,000
Performance Based Awards (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reduction in number of shares available for issuance under the 2007 Plan per award granted			2
Granted shares			88,000
Vested shares			0
Outstanding shares	88,000		88,000		0
Weighted-average grant date fair value per granted share \| $ / shares	$ 50.75	$ 48.89	$ 52.45	$ 53.93
Grant date fair value of awards released \| $				$ 3,200,000
Number of performance-based awards shares released as percentage of target number, minimum			0.00%
Number of performance-based awards shares released as percentage of target number, maximum			200.00%
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			4 years
Allocated stock-based compensation expense \| $	$ 200,000	$ 500,000	$ 400,000	1,000,000
Performance Based Awards and Long Term Performance based Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated stock-based compensation expense \| $	$ 200,000	$ 700,000	$ 800,000	$ 1,300,000
Long-Term Performance-based Awards (PRSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reduction in number of shares available for issuance under the 2007 Plan per award granted			2
Granted shares			72,000
Vested shares			0
Outstanding shares	133,000		133,000		61,000
Weighted-average grant date fair value per granted share \| $ / shares	$ 49.40	$ 47.95	$ 52.47	$ 56.15
Number of performance-based awards shares released as percentage of target number, minimum			0.00%
Number of performance-based awards shares released as percentage of target number, maximum			200.00%
Equity Incentive Plan 2007 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			48 months
Equity Incentive Plan 2007 [Member] \| Incentive Stock Options [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%
Equity Incentive Plan 2007 [Member] \| Nonstatutory Stock Options [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%
Directors Equity Compensation Program [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Factor used to determine the number of options/units to be granted \| $			$ 100,000
Directors Equity Compensation Program [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Factor used to determine the number of options/units to be granted \| $			100,000
Directors Equity Compensation Program [Member] \| Stock Options and Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Factor used to determine the number of options/units to be granted \| $			$ 100,000