STOCK-BASED COMPENSATION (Tables)

3 Months Ended

Jun. 30, 2011

Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]

Stock-Based Compensation Expense Included in Statements of Operations [Table Text Block]

The following table summarizes the amount of stock-based compensation expense included in the Condensed consolidated statements of operations:

	Three Months Ended
	June 30,
(in thousands)	2011			2010
Cost of revenues	$	546		$	533
Research, development and engineering	947			937
Selling, general and administrative	2,686			2,307
Stock-based compensation expense included in operating expenses	3,633			3,244
Total stock-based compensation	4,179			3,777
Income tax benefit	(1,282		)	(1,041		)
Total stock-based compensation, net of tax	$	2,897		$	2,736

Summary of Stock Option Activity [Table Text Block]

The following is a summary of the Company’s stock option activity during the three months ended June 30, 2011:

	Options Outstanding
	Number of Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Life	Aggregate Intrinsic Value
	(in thousands)				(in years)	(in thousands)
Outstanding at March 31, 2011	5,360		$	25.58
Options granted	327		$	36.51
Options exercised	(552	)	$	20.87
Options forfeited or expired	(52	)	$	36.87
Outstanding at June 30, 2011	5,083		$	26.68	3.2	$	55,305
Vested and expected to vest at June 30, 2011	4,968		$	26.56	3.2	$	54,715
Exercisable at June 30, 2011	3,778		$	25.89	2.3	$	44,704

Summary of Restricted Stock Activity [Table Text Block]

The following is a summary of the Company’s restricted stock activity during the three months ended June 30, 2011:

	Number of Shares		Weighted Average Grant Date Fair Value
	(in thousands)
Non-vested at March 31, 2011	688		$	29.52
Restricted stock granted	366		$	36.60
Restricted stock vested	(46	)	$	29.02
Restricted stock forfeited	(3	)	$	33.01
Non-vested at June 30, 2011	1,005		$	32.23

Valuation Assumptions [Table Text Block]

The fair value of stock option and ESPP shares granted during the respective periods is estimated on the date of grant using the following weighted average assumptions:

	Three Months Ended
	June 30,
Employee Stock Options	2011			2010
Expected volatility	44.4		%	46.1		%
Risk-free interest rate	1.4		%	1.9		%
Expected dividends	0.6		%	0.7		%
Expected life (in years)	4.0			4.2
Weighted-average grant date fair value	$	12.58		$	11.26