STOCK-BASED COMPENSATION

6 Months Ended

Sep. 30, 2011

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

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

STOCK-BASED COMPENSATION

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

	Three Months Ended						Six Months Ended
	September 30,						September 30,
(in thousands)	2011			2010			2011			2010
Cost of revenues	$	559		$	565		$	1,105		$	1,098
Research, development and engineering	1,028			967			1,975			1,904
Selling, general and administrative	2,921			2,480			5,608			4,787
Stock-based compensation expense included in operating expenses	3,949			3,447			7,583			6,691
Total stock-based compensation expense	4,508			4,012			8,688			7,789
Income tax benefit	(1,441		)	(1,305		)	(2,723		)	(2,346		)
Total stock-based compensation expense, net of tax	$	3,067		$	2,707		$	5,965		$	5,443

Stock Options

The following is a summary of the Company’s stock option activity during the six months ended September 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	424		$	35.54
Options exercised	(795	)	$	20.95
Options forfeited or expired	(703	)	$	39.33
Outstanding at September 30, 2011	4,286		$	25.17	3.6	$	21,669
Vested and expected to vest at September 30, 2011	4,186		$	24.99	3.5	$	21,573
Exercisable at September 30, 2011	3,119		$	23.18	2.7	$	19,052

The total intrinsic value of options exercised during the six months ended September 30, 2011 and 2010 was $11.7 million and $5.1 million, respectively.  Intrinsic value is defined as the amount by which the fair value of the underlying stock exceeds the exercise price at the time of option exercise. The total cash received as a result of stock option exercises during the six months ended September 30, 2011 was $16.7 million.

As of September 30, 2011, total unrecognized compensation cost related to unvested stock options was $10.0 million which is expected to be recognized over a weighted average period of 1.9 years.

Restricted Stock

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

	Number of Shares		Weighted Average Grant Date Fair Value
	(in thousands)
Unvested at March 31, 2011	688		$	29.52
Restricted stock granted	390		$	36.36
Restricted stock vested	(68	)	$	27.90
Restricted stock forfeited	(28	)	$	29.64
Unvested at September 30, 2011	982		$	32.47

The weighted average grant-date fair value of awards of restricted stock and restricted stock units (collectively "restricted stock") is based on the quoted market price of the Company's common stock on the date of grant. The weighted average grant-date fair value of restricted stock granted during the six months ended September 30, 2011 and 2010 was $36.36 and $30.16, respectively. The total fair value of restricted stock that vested during the six months ended September 30, 2011 and 2010 was $1.9 million and $0.7 million, respectively.

As of September 30, 2011, total unrecognized compensation cost related to unvested restricted stock was $21.0 million which is expected to be recognized over a weighted average period of 2.9 years.  

Valuation Assumptions

The Company estimates the fair value of stock options and Employee Stock Purchase Plan (“ESPP”) shares using a Black-Scholes option valuation model.  The fair value of stock options and ESPP shares granted during the respective periods is estimated on the date of grant using the following weighted average assumptions:

	Three Months Ended						Six Months Ended
	September 30,						September 30,
Employee Stock Options	2011			2010			2011			2010
Expected volatility	44.7		%	46.6		%	44.4		%	46.3		%
Risk-free interest rate	0.6		%	1.2		%	1.2		%	1.7		%
Expected dividends	0.6		%	0.7		%	0.6		%	0.7		%
Expected life (in years)	4.0			4.2			4.0			4.2
Weighted-average grant date fair value	$	10.85		$	11.14		$	12.18		$	11.22
ESPP
Expected volatility	38.7		%	41.8		%	38.7		%	41.8		%
Risk-free interest rate	0.1		%	0.2		%	0.1		%	0.2		%
Expected dividends	0.6		%	0.7		%	0.6		%	0.7		%
Expected life (in years)	0.5			0.5			0.5			0.5
Weighted-average grant date fair value	$	8.00		$	8.02		$	8.00		$	8.02

The Company recognizes the grant-date fair value of stock-based compensation as compensation expense in the Condensed consolidated statements of operations using the straight-line attribution approach over the service period for which the stock-based compensation is expected to vest.