Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2017

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

Schedule of Stock-based Compensation Expense

Stock-based compensation expense by statement of operations caption and the related income tax benefit were as follows:



	Year Ended December 31,
(In thousands)	2017		2016		2015
Cost of sales	$	71	$	57	$	39
Research and development expenses	551		541		428
Selling, general and administrative expenses:
Employees	7,368		7,095		5,946
Outside directors	3,953		2,631		1,500
Total employee and director stock-based compensation expense	$	11,943	$	10,324	$	7,913

Income tax benefit	$	2,954	$	3,102	$	2,366

Schedule of Black Scholes Assumptions

The assumptions we utilized in the Black-Scholes option pricing model and the resulting weighted average fair value of stock option grants were the following:



	Year Ended December 31,
	2017			2016			2015
Weighted average fair value of grants	$	19.61		$	17.96		$	24.47
Risk-free interest rate	1.75		%	1.36		%	1.39		%
Expected volatility	34.25		%	41.38		%	43.36		%
Expected life in years	4.52			4.55			4.57

Schedule of Stock Option Activity

Stock option activity was as follows:



	2017							2016							2015
	Number of Options (in 000's)		Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value (in 000's)		Number of Options (in 000's)		Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value (in 000's)		Number of Options (in 000's)		Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value (in 000's)
Outstanding at beginning of the year	652		$	39.27				648		$	30.50				650		$	25.56
Granted	92		62.70					243		49.67					77		64.81
Exercised	(56	)	25.72			$	2,140	(239	)	26.09			$	9,933	(71	)	23.97			$	2,193
Forfeited/canceled/expired	(168	)	46.44					—		—					(8	)	20.64
Outstanding at end of the year ⁽¹⁾	520		$	42.56	4.25	$	5,607	652		$	39.27	4.78	$	16,553	648		$	30.50	4.85	$	14,556
Vested and expected to vest at the end of the year ⁽¹⁾	520		$	42.56	4.25	$	5,607	652		$	39.27	4.78	$	16,548	648		$	30.50	4.85	$	14,551
Exercisable at the end of the year ⁽¹⁾	381		$	36.39	3.72	$	5,607	363		$	30.21	3.88	$	12,511	493		$	25.03	4.51	$	12,979

⁽¹⁾

The aggregate intrinsic value represents the total pre-tax value (the difference between our closing stock price on the last trading day of 2017, 2016, and 2015 and the exercise price, multiplied by the number of in-the-money options) that would have been received by the option holders had they all exercised their options on December 31, 2017, 2016, and 2015. This amount will change based on the fair market value of our stock.

Schedule of Exercise Price Range and Life Information

Significant option groups outstanding at December 31, 2017 and the related weighted average exercise price and life information were as follows:



	Options Outstanding				Options Exercisable
Range of Exercise Prices	Number Outstanding (in 000’s)	Weighted-Average Remaining Contractual Term (in years)	Weighted-Average Exercise Price		Number Exercisable (in 000’s)	Weighted-Average Exercise Price
$18.25 to $21.95	155	3.79	$	19.92	155	$	19.92
26.48 to 27.74	17	0.30	27.02		17	27.02
35.28	85	3.12	35.28		85	35.28
51.38 to 65.54	263	5.14	59.31		124	59.10
	520	4.25	$	42.56	381	$	36.39

Schedule of Non-vested Restricted Stock Awards Activity

Non-vested restricted stock award activity was as follows:



	2017				2016				2015
	Shares (in 000’s)		Weighted-Average Grant Date Fair Value		Shares (in 000’s)		Weighted-Average Grant Date Fair Value		Shares (in 000’s)		Weighted-Average Grant Date Fair Value
Non-vested at beginning of the year	153		$	57.43	225		$	51.31	266		$	39.28
Granted	133		64.14		77		63.30		138		53.64
Vested	(119	)	59.67		(146	)	51.10		(178	)	35.09
Forfeited	(5	)	60.11		(3	)	60.17		(1	)	63.19
Non-vested at end of the year	162		$	61.19	153		$	57.43	225		$	51.31

Schedule of Information Regarding Stock Incentive Plans

Detailed information regarding our active Stock Incentive Plans was as follows at December 31, 2017:



Name	Approval Date	Initial Shares Available for Grant Under the Plan	Remaining Shares Available for Grant Under the Plan	Outstanding Shares Granted Under the Plan
1999A Stock Incentive Plan	10/7/1999	1,000,000	—	7,500
2003 Stock Incentive Plan	6/18/2003	1,000,000	—	14,391
2006 Stock Incentive Plan	6/13/2006	1,000,000	—	82,572
2010 Stock Incentive Plan	6/15/2010	1,000,000	—	203,303
2014 Stock Incentive Plan	6/12/2014	1,100,000	448,051	373,673
			448,051	681,439