STOCK-BASED COMPENSATION (Tables)

12 Months Ended

Dec. 31, 2017

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

Summary Of Employee Stock-Based Compensation Expense

Stock-based compensation expense - all related to employees and members of the Board of Directors - recognized under the authoritative guidance was as follows:

	Years Ended December 31,
	2017		2016		2015
	(In thousands)
Selling, general and administrative	$	19,785	$	15,829	$	14,461
Research and development	1,273		1,048		714
Cost of goods sold	492		433		275
Total stock-based compensation expense	21,550		17,310		15,450
Total estimated tax benefit related to stock-based compensation expense	15,448		10,569		5,792
Net effect on net income	$	6,102	$	6,741	$	9,658

Summary Of Weighted-Average Assumptions

The following weighted-average assumptions were used in the calculation of fair value:

	Years Ended December 31,
	2017	2016	2015
Dividend yield	0%	0%	0%
Expected volatility	30%	29%	29%
Risk free interest rate	2.18%	1.94%	1.96%
Expected life of option from grant date	8 years	8 years	8 years

Summary Of Stock Option Activity

The following table summarizes the Company’s stock option activity.

			Weighted Average Exercise Price		Weighted Average Contractual Term in Years	Aggregate Intrinsic Value
	Shares
Stock Options	(In thousands)					(In thousands)
Outstanding at January 1, 2017	2,083		$	20.65
Granted	187		41.72
Exercised	(531	)	17.60
Forfeited or Expired	—		—
Outstanding at December 31, 2017	1,739		$	23.84	3.54	$	41,753
Vested or expected to vest at December 31, 2017	1,739		$	23.84	3.54	$	41,753
Exercisable at December 31, 2017	1,333		$	19.95	2.63	$	37,208

Summary Of Restricted Stock, Performance Stock, and Contract Stock

The following table summarizes the Company’s awards of restricted stock, performance stock and contract stock for the year ended December 31, 2017.

					Performance Stock and Contract Stock Awards
	Restricted Stock Awards
	Shares		Weighted Average Grant Date Fair Value Per Share		Shares		Weighted Average Grant Date Fair Value Per Share
	(In thousands)				(In thousands)
Unvested, January 1, 2017	512		$	28.49	345		$	21.62
Granted	286		44.15		213		43.75
Adjustments for performance achievement related to award target	—		—		25		36.90
Cancellations	(61	)	36.00		(12	)	30.52
Released	(286	)	27.89		(225	)	43.11
Vested but not released	—		—		(174	)	32.40
Unvested, December 31, 2017	451		$	37.79	172		$	33.61