Employee Benefits and Share-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2017

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, 2017		March 31, 2016
	(In thousands)
Cost of product and service revenues	$	982	$	549
Research and development	897		641
Selling, general and administrative	3,632		2,701
Total share-based compensation expense	$	5,511	$	3,891

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

	Three months ended
	March 31, 2017		March 31, 2016
Employee Stock Purchase Plan
Expected life, years	0.5-2.0		0.5-2.0
Expected volatility, %	25.8-32.8%		25.8-34.8%
Risk free interest rate, %	0.52-1.31%		0.26-0.79%
Dividend yield, %	—	%	—	%

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, 2017 and 2016:

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, 2017 and 2016:

	Three months ended
	March 31, 2017		March 31, 2016
Stock Option Plans
Expected life, years	4.67		4.92
Expected volatility, %	31.1	%	32.6	%
Risk free interest rate, %	1.89	%	1.40	%
Estimated forfeiture rate %	7.7	%	8.6	%
Dividend yield, %	—	%	—	%

Stock Option Activity under the Equity Incentive Plans

The following table summarizes the share option activity under the Company’s equity incentive plans during the three months ended March 31, 2017:

	Number of Shares		Weighted-Average Exercise Price		Weighted-Average Remaining Years	Aggregate Intrinsic Value
	(In thousands, except per share data)
Stock Options
Outstanding at December 31, 2016	3,214		$	26.06	7.3	$	26,331
Granted	363		36.67
Exercised	(188	)	22.86
Expired	(1	)	32.59
Forfeited	(38	)	31.72
Outstanding at March 31, 2017	3,350		$	27.33	7.4	$	44,631
Exercisable at March 31, 2017	1,493		$	20.88	5.5	$	29,519
Vested and expected to vest at March 31, 2017 and thereafter	3,168		$	26.96	7.3	$	43,388

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

The following table summarizes the restricted stock activity under the Company’s equity incentive plans during the three months ended March 31, 2017:

	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 ("RSUs")
Outstanding at December 31, 2016	505		$	31.42	1.6	$	17,135
Granted	74		36.57
Vested	(43	)	28.12
Forfeited	(9	)	31.97
Outstanding and unvested at March 31, 2017	527		$	32.39	1.5	$	21,418

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 ("RSAs")
Outstanding at December 31, 2016	30	$	31.57
Granted	—
Vested	—
Forfeited	—
Outstanding and unvested at March 31, 2017	30	$	31.57

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

The following table summarizes the performance-based restricted stock activity under the Company’s equity incentive plans during the three months ended March 31, 2017:

	Number of Shares		Weighted-Average Grant Date Fair Value Per Unit
	(In thousands, except per share data)
Performance-based Restricted Stock Units ("PSUs")
Outstanding at December 31, 2016	184		$	24.89
Granted	126		32.37
Vested	(31	)	24.66
Forfeited	—		—
Outstanding and unvested at March 31, 2017	279		$	28.29

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, 2017

	Number of Shares
	(In thousands)
Share options outstanding	3,350
Non-vested restricted share awards	836
Shares authorized for future issuance	2,411
ESPP shares available for future issuance	2,572
Total shares reserved for future issuance	9,169