Share-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2020

Share-Based Compensation

Schedule of share-based compensation expense

		Three months ended March 31,
		2020		2019
	(in thousands)
Cost of sales		$	521	$	470
Research and development			874		792
Selling, general, and administrative			2,251		1,895
Total		$	3,646	$	3,157

Summary of stock option activity

		Weighted
	Number of	Average
	Shares	Exercise Price
	(in thousands)
Balance - December 31, 2019	1,119		34.88
Expired or forfeited	(40)		34.19
Balance - March 31, 2020	1,079		34.90

Summary of non-vested restricted and performance shares activity

		Weighted
		Average
	Number of	Grant Date
	Shares	Fair Value
	(in thousands)
Balance - December 31, 2019	2,257		16.20
Granted	840		8.99
Performance award adjustments	(45)		31.34
Vested	(190)		12.68
Forfeited	(233)		16.35
Balance - March 31, 2020	2,629		13.88