Share-based compensation (Tables)

6 Months Ended

Jun. 30, 2015

Share-based compensation

Schedule of share-based compensation expense

	Three months ended June 30,				Six months ended June 30,
	2015		2014		2015		2014
	(in thousands)
Cost of sales	$	713	$	620	$	1,314	$	1,180
Selling, general, and administrative	3,112		3,324		5,910		6,425
Research and development	1,096		1,147		1,695		2,208
Total share-based compensation expense	$	4,921	$	5,091	$	8,919	$	9,813

Summary of restricted share activity

			Weighted Average Grant Date
	Number of Shares		Fair Value
	(in thousands)
Restricted shares outstanding - December 31, 2014	1,237		$	34.27
Granted	597		31.32
Vested	(125	)	40.70
Forfeited	(59	)	35.92
Restricted shares outstanding - June 30, 2015	1,650		$	32.66

Summary of stock option activity

			Weighted Average
	Number of Shares		Exercise Price
	(in thousands)
Stock options outstanding - December 31, 2014	2,391		$	31.65
Granted	17		30.22
Exercised	(74	)	19.07
Expired or forfeited	(119	)	38.62
Stock options outstanding - June 30, 2015	2,215		$	31.69