STOCK PLANS AND SHARE-BASED COMPENSATION (Tables)

3 Months Ended

Mar. 31, 2013

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock-based Compensation Expense [Table Text Block]

The following table summarizes the stock-based compensation expense recognized in accordance with ASC 718-10 for the three months ended March 31, 2013, and March 31, 2012 (in thousands).

	Three Months Ended
	March 31,
	2013		2012
Cost of revenues	$	264	$	245
Research and development	1,106		1,120
Sales and marketing	829		747
General and administrative	1,437		919
Total stock-based compensation expense	$	3,636	$	3,031

Schedule of Unrecognized Compensation Expense for Unvested Awards [Table Text Block]

The following table summarizes total compensation expense related to unvested awards not yet recognized, net of expected forfeitures, and the weighted-average period over which it is expected to be recognized as of March 31, 2013.

	March 31, 2013
	Unrecognized Compensation Expense for Unvested Awards			Weighted Average Remaining Recognition Period
	(In thousands)			(In years)
Options		$	3,042		1.89
Performance-based awards		1,662			0.75
Restricted stock units		19,029			2.71
Purchase plan		379			0.5
Total unrecognized compensation expense		$	24,112

Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block]

The fair value of employees’ stock purchase rights under the Purchase Plan was estimated using the Black-Scholes model with the following weighted-average assumptions:

	Three Months Ended
	March 31,
	2013	2012
Risk-free interest rates	0.11%	0.09%
Expected volatility rates	33%	48%
Expected dividend yield	0.80%	0.54%
Expected term of purchase right (in years)	0.5	0.5
Weighted-average estimated fair value of purchase rights	$9.14	$10.42

Summary of Option Activity Under the Plans [Table Text Block]

A summary of stock option activity under the Plans, excluding performance-based awards and restricted stock units, as of March 31, 2013, and changes during the three months then ended is presented below:

	Shares (in thousands)		Weighted- Average Exercise Price	Weighted-Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value (in thousands)
Outstanding at January 1, 2013	2,817		$26.00
Granted	—		—
Exercised	(274	)	$24.05
Forfeited or expired	—		—
Outstanding at March 31, 2013	2,543		$26.21	4.29	$	43,741
Exercisable at March 31, 2013	2,255		$24.67	3.79	$	42,250
Vested and expected to vest at March 31, 2013	2,531		$26.14	4.27	$	43,709

Summary of Performance-based Awards Activity [Table Text Block]

A summary of performance-based awards outstanding as of March 31, 2013, and activity during the three months then ended, is presented below:

	Shares (in thousands)		Weighted- Average Grant Date Fair Value Per Share	Weighted-Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value (in thousands)
Outstanding at January 1, 2013	102		$37.60
Granted	60		$36.43
Vested	(54	)	$37.60
Change in units due to performance achievement for PSUs vested in the year	(48	)	$37.60
Forfeited or expired	—		—
Outstanding at March 31, 2013	60		$36.43	0.75	$	2,598
Outstanding and expected to vest at March 31, 2013	57			0.75	$	2,490

Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block]

A summary of RSUs outstanding as of March 31, 2013, and changes during the three months then ended, is as follows:

	Shares (in thousands)		Weighted- Average Grant Date Fair Value Per Share	Weighted-Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value (in thousands)
Outstanding at January 1, 2013	573		$38.21
Granted	174		$35.68
Vested	(6	)	$36.62
Forfeited or expired	(12	)	$38.66
Outstanding at March 31, 2013	729		$37.90	1.51	$	31,663
Outstanding and expected to vest at March 31, 2013	676			1.49	$	29,337