Employee Benefits and Share-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2015

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

Share-Based Compensation Expense Recognized in Consolidate Statements of Income

The following table sets forth the total share-based compensation expense recognized in our Condensed Consolidated Statements of Income:

	Three Months Ended
	March 31, 2015		March 31, 2014
	(In thousands)
Cost of product and service revenues	$	517	$	268
Research and development	434		369
Selling, general and administrative	2,714		2,092
Total share-based compensation expense	$	3,665	$	2,729

Stock Option Activity under the 2009 Plan

A summary of the stock option activity under the 2009 Plan is presented below:

	Number of Shares		Weighted-Average Exercise Price		Weighted-Average Remaining Years	Aggregate Intrinsic Value(1)
	(In thousands, except per share data)
Outstanding at December 31, 2014	2,672		$	19.02	6.5
Granted	151		33.73
Exercised	(132	)	15.69
Expired	—		—
Forfeited	(16	)	22.60
Outstanding at March 31, 2015	2,675		$	19.98	6.6	$	40,442
Exercisable at March 31, 2015	1,529		$	16.11	5.0	$	29,042
Vested and expected to vest at March 31, 2015	2,643		$	19.88	6.5	$	40,234

_________________________________________________

⁽¹⁾  Intrinsic value is calculated as the difference between the market value or closing price of our common stock as of the last trading day of the year as reported by the NASDAQ Global Select Market, and the exercise price of the option.

Restricted Stock Units Activity under the 2009 Plan

A summary of the restricted stock activity under the 2009 Plan is presented below:

	Number of Shares		Weighted-Average Grant Date Fair Value		Weighted-Average Remaining Years	Aggregate Intrinsic Value
	(In thousands, except per share data)
Restricted Stock Units
Outstanding at December 31, 2014	399		$	24.00	1.5
Granted	44		33.97
Vested	(26	)	22.07
Forfeited	(6	)	21.73
Outstanding and unvested at March 31, 2015	411		$	25.21	1.4	$	14,431
Expected to vest at March 31, 2015	399				1.4	$	13,997

Restricted Stock Units Award under the 2009 Plan

	Number of Shares	Weighted-Average Grant Date Fair Value
	(In thousands, except per share data)
Restricted Stock Awards
Outstanding at December 31, 2014	36	$	17.49
Granted	—	—
Vested	—	—
Forfeited	—	—
Outstanding and unvested at March 31, 2015	36	$	17.49

Performance Shares Restricted Stock Activity under the 2009 Plan

A summary of the performance-based restricted stock activity under the 2009 Plan is presented below:

	Number of Shares		Weighted-Average Grant Date Fair Value Per Unit
	(In thousands, except per share data)
Unvested at December 31, 2014	233		$	17.96
Granted	60		29.56
Vested	(33	)	21.26
Cancelled	—		—
Unvested at March 31, 2015	260		$	20.23