Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2016

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock-Based Compensation Expense Related to Stock Options, Restricted Stock Units (RSUs) and Restricted Stock

The following table summarizes the stock-based compensation expense related to stock options, restricted stock units (RSUs) and restricted stock for the three months ended March 31, 2016 and 2015, which was recognized as follows:

	Three Months Ended March 31,
(In thousands)	2016			2015
Stock-based compensation expense included in cost of sales	$	99		$	90
Selling, general and administrative expense		769			691
Research and development expense		690			858
Stock-based compensation expense included in operating expenses		1,459			1,549
Total stock-based compensation expense		1,558			1,639
Tax benefit for expense associated with non-qualified options		(212	)		(180	)
Total stock-based compensation expense, net of tax	$	1,346		$	1,459

Summary of Weighted-Average Assumptions and Value of Options Granted

The weighted-average assumptions and value of options granted during the three months ended March 31, 2015 were as follows:

	Three Months
	Ended
	March 31,
	2015
Expected volatility		38.75	%
Risk-free interest rate		1.46	%
Expected dividend yield		1.60	%
Expected life (in years)		6.47
Weighted-average estimated value	$	7.63

Summary of Stock Options Outstanding

The following table is a summary of our stock options outstanding as of December 31, 2015 and March 31, 2016 and the changes that occurred during the three months ended March 31, 2016:

(In thousands, except per share amounts)	Number of Options			Weighted Avg. Exercise Price		Weighted Avg. Remaining Contractual Life In Years		Aggregate Intrinsic Value
Options outstanding, December 31, 2015		7,108		$	21.97		6.42	$	3,284
Options granted		—		$	—
Options exercised		(15	)	$	16.65
Options forfeited		(23	)	$	17.84
Options expired		(26	)	$	24.40
Options outstanding, March 31, 2016		7,044		$	22.00		6.18	$	11,580
Options vested and expected to vest, March 31, 2016		6,910		$	22.10		6.12	$	11,095
Options exercisable, March 31, 2016		4,466		$	24.33		4.69	$	4,191