Employee Benefits and Share-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2016

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 the Company's Condensed Consolidated Statements of Operations:

	Three months ended
	March 31, 2016		March 31, 2015
	(In thousands)
Cost of product and service revenues	$	549	$	517
Research and development	641		434
Selling, general and administrative	2,701		2,714
Total share-based compensation expense	$	3,891	$	3,665

Estimate of Fair Value of Share-Based Awards, Employee Stock Purchase Plan

The following weighted average assumptions are used to value stock options and Employee Stock Purchase Plan ("ESPP") shares issued pursuant to the Company's equity incentive plans for the three months ended March 31, 2016 and March 31, 2015:

	Three months ended
	March 31, 2016		March 31, 2015
	(In thousands, except percentages)
Stock Option Plans
Expected life, years	4.92		5.04
Expected volatility, %	32.6	%	33.2	%
Risk free interest rate, %	1.40	%	1.66	%
Estimated forfeiture rate %	8.6	%	2.5	%
Dividend yield, %	—	%	—	%

	Three months ended
	March 31, 2016		March 31, 2015
	(In thousands, except percentages)
Employee Stock Purchase Plan
Expected life, years	0.5-2.0		0.5-2.0
Expected volatility, %	25.79-34.79%		28.52-37.53%
Risk free interest rate, %	0.26-0.79%		0.03-0.53%
Dividend yield, %	—	%	—	%

Estimate of Fair Value of Share-Based Awards, Share Options

The following weighted average assumptions are used to value stock options and Employee Stock Purchase Plan ("ESPP") shares issued pursuant to the Company's equity incentive plans for the three months ended March 31, 2016 and March 31, 2015:

	Three months ended
	March 31, 2016		March 31, 2015
	(In thousands, except percentages)
Stock Option Plans
Expected life, years	4.92		5.04
Expected volatility, %	32.6	%	33.2	%
Risk free interest rate, %	1.40	%	1.66	%
Estimated forfeiture rate %	8.6	%	2.5	%
Dividend yield, %	—	%	—	%

	Three months ended
	March 31, 2016		March 31, 2015
	(In thousands, except percentages)
Employee Stock Purchase Plan
Expected life, years	0.5-2.0		0.5-2.0
Expected volatility, %	25.79-34.79%		28.52-37.53%
Risk free interest rate, %	0.26-0.79%		0.03-0.53%
Dividend yield, %	—	%	—	%

Stock Option Activity under the Equity Incentive Plans

A summary of the stock options 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)
Stock Options
Outstanding at December 31, 2015	2,688		$	22.89	6.9
Granted	376		27.75
Exercised	(49	)	13.48
Expired	(1	)	19.96
Forfeited	(38	)	28.51
Outstanding at March 31, 2016	2,976		$	23.59	7.0	$	15,891
Exercisable at March 31, 2016	1,478		$	18.53	5.0	$	14,329
Vested and expected to vest at March 31, 2016 and thereafter	2,790		$	23.23	6.9	$	15,806

Restricted Stock Units Activity under the Stock Option Activity under the Equity Incentive Plans

Summaries of restricted stock activity under the 2009 Plan are 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 ("RSU")
Outstanding at December 31, 2015	417		$	28.49	1.6
Granted	90		27.77
Vested	(23	)	25.76
Forfeited	(7	)	28.42
Outstanding and unvested at March 31, 2016	477		$	28.49	1.5	$	13,292
Expected to vest after March 31, 2016	419		$	28.39	1.4	$	11,677

Restricted Stock Units Award under the Stock Option Activity under the Equity Incentive Plans

	Number of Shares	Weighted-Average Grant Date Fair Value
	(In thousands, except per share data)
Restricted Stock Awards ("RSA")
Outstanding at December 31, 2015	31	$	35.98
Granted	—	—
Vested	—	—
Forfeited	—	—
Outstanding and unvested at March 31, 2016	31	$	35.98

Performance Shares Restricted Stock Activity under the Stock Option Activity under the Equity Incentive Plans

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

	Number of Shares		Weighted-Average Grant Date Fair Value Per Unit
	(In thousands, except per share data)
Performance-based Restricted Stock Units ("PSU")
Outstanding at December 31, 2015	151		$	23.33
Granted	123		24.66
Vested	(15	)	29.56
Forfeited	—		—
Outstanding and unvested at March 31, 2016	259		$	23.60

Shares Reserved for Future Issuance under the Stock Option Activity under the Equity Incentive Plans

The Company had the following ordinary shares reserved for future issuance under its equity incentive plans as of March 31, 2016:

	Number of Shares
	(In thousands)
Share options outstanding	2,976
Non-vested restricted share awards	767
Shares authorized for future issuance	3,017
ESPP shares available for future issuance	3,053
Total shares reserved for future issuance	9,813