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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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- Definition

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

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No definition available.

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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, Award Expiration Period

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- Definition

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

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- Definition

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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- 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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- Definition

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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- Definition

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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- Definition

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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- Definition

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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- Definition

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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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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STOCK PLANS AND SHARE-BASED COMPENSATION (Details) (USD $)	0 Months Ended	3 Months Ended
	Mar. 31, 2015 plans	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock-based compensation plans	2
Awards expiration period, maximum (in years)		10 years
Allocated stock-based compensation expense		$ 4,391,000	$ 3,915,000
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%	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 period in each offering period		1
Duration of each purchase period in each offering period		6 months
Shares reserved for issuance	3,000,000	3,000,000
Employee shares purchased for award	2,747,784	2,747,784
Shares available for grant	252,216	252,216
Allocated stock-based compensation expense		300,000	300,000
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		3,300,000	2,600,000
Reduction in number of shares available for issuance under the 2007 Plan per award granted		2
Granted shares		104,000
Vested shares		64,000
Outstanding shares	729,000	729,000		692,000
Weighted-average grant date fair value per granted share		$ 52.25	$ 57.05
Grant date fair value of awards released		2,700,000	1,600,000
Performance Based Awards (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of performance-based awards shares released as percentage of target number, maximum		200.00%
Number of performance-based awards shares released as percentage of target number, minimum		0.00%
Allocated stock-based compensation expense		600,000	500,000
Reduction in number of shares available for issuance under the 2007 Plan per award granted		2
Granted shares		50,000
Vested shares		0
Outstanding shares	50,000	50,000		0
Weighted-average grant date fair value per granted share		$ 53.74	$ 58.55
Grant date fair value of awards released			3,200,000
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
Long-Term Performance-based Awards (PRSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of performance-based awards shares released as percentage of target number, maximum		200.00%
Number of performance-based awards shares released as percentage of target number, minimum		0.00%
Reduction in number of shares available for issuance under the 2007 Plan per award granted		2
Granted shares		65,000
Vested shares		0
Outstanding shares	126,000	126,000		61,000
Weighted-average grant date fair value per granted share		$ 52.80	$ 57.76
2007 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		48 months
2007 Equity Incentive Plan [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%
2007 Equity Incentive Plan [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
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for future issuance	6,582,346	6,582,346