Share-based compensation (Tables)

3 Months Ended

Mar. 31, 2015

Share-based compensation

Schedule of share-based compensation expense

	Three months ended March 31,
	2015		2014
	(in thousands)
Cost of sales	$	601	$	560
Selling, general, and administrative	2,798		3,101
Research and development	599		1,061
Total share-based compensation expense	$	3,998	$	4,722

Summary of restricted stock awards and restricted stock unit activity

			Weighted Average
			Grant Date
	Number of Shares		Fair Value
	(in thousands)
Restricted shares outstanding - December 31, 2014	1,237		$	34.27
Granted	39		31.56
Vested	(4	)	32.88
Forfeited	(53	)	35.99
Restricted shares outstanding - March 31, 2015	1,219		$	34.11

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	10		30.49
Exercised	(10	)	28.77
Expired or forfeited	(62	)	36.03
Stock options outstanding - March 31, 2015	2,329		$	31.54