Stock Options And Employee Stock Purchase Plan (Tables)

12 Months Ended

Dec. 31, 2014

Stock Options Activity

Stock option activity for the years ended December 31, 2014, 2013 and 2012 is summarized as follows:

	Number of Shares		Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Life (In Years)	Aggregate Intrinsic Value
Options outstanding at December 31, 2011	2,087,695		$	20.99
Granted	67,000		27.26
Exercised	(357,234	)	15.81
Canceled	(32,000	)	31.34
Options outstanding at December 31, 2012	1,765,461		$	22.08
Granted	—		—
Exercised	(569,204	)	23.90
Canceled	(20,600	)	21.79
Options outstanding at December 31, 2013	1,175,657		$	21.08
Granted	—		—
Exercised	(433,008	)	15.70
Canceled	(17,000	)	29.85
Options outstanding at December 31, 2014	725,649		$	24.29	3.9	$27,362,157
Exercisable at December 31, 2014	618,437		$	23.77	3.4	$23,642,294
Vested and expected to vest at December 31, 2014	714,319		$	24.24	3.8	$26,975,686

Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table Text Block]

The following table summarizes information concerning outstanding and exercisable options as of December 31, 2014:

	Options Outstanding				Exercisable Options
Range of Exercise Prices	Number Outstanding December 31, 2014	Weighted Average Remaining Contractual Life	Weighted Average Exercise Price		Number Exercisable December 31, 2014	Weighted Average Exercise Price
$17.19	49,283	4.18 years	$	17.19	49,283	$	17.19
18.77	128,200	0.67 years	18.77		128,200	18.77
20.91	77,448	3.34 years	20.91		77,448	20.91
21.67 - 21.88	74,420	4.21 years	31.69		74,420	21.69
22.92	98,716	5.35 years	22.92		76,780	22.92
23.11 - 28.52	75,382	4.95 years	26.87		44,382	27.06
29.34	90,700	6.36 years	29.34		54,424	29.34
29.53	22,000	7.17 years	29.53		7,000	29.53
31.07	7,500	6.82 years	31.07		4,500	31.07
32.45	102,000	2.59 years	32.45		102,000	32.45
$17.19 - $32.45	725,649	3.88 years	$	24.29	618,437	$	23.77

Assumptions To Estimate Fair Value Of Stock Options

The weighted-average fair values of stock options granted have been estimated utilizing the following assumptions:

	Year Ended December 31,
	2012
Risk-free interest rate	1.1%
Expected term (in years)	5.7
Dividend yield	3.2%
Expected volatility	41.6%

Allocation Of Share-Based Compensation Expense

The following table represents share-based compensation expense included in cost of revenues and operating expenses in the consolidated statements of income for the years ended December 31, 2014, 2013 and 2012 (in thousands):

	Year Ended December 31,
	2014		2013		2012
Cost of revenues	$	345	$	756	$	844
Operating expenses:
Sales and marketing	1,944		1,855		1,543
Research, development and engineering	721		434		459
General and administrative	5,898		6,675		6,286
	$	8,908	$	9,720	$	9,132

Restricted Stock [Member]

Restricted Stock And Restricted Stock Unit Award Activity

Restricted stock award activity for the years ended December 31, 2014 and 2013 is set forth below:

	Shares		Weighted-Average Grant-Date Fair Value
Nonvested at January 1, 2013	828,475		$	23.08
Granted	690,762		13.57
Vested	(296,966	)	21.46
Canceled	(43,900	)	24.46
Nonvested at December 31, 2013	1,178,371		$	17.86
Granted	226,864		45.66
Vested	(546,115	)	15.63
Canceled	(45,070	)	35.55
Nonvested at December 31, 2014	814,050		$	26.57

Restricted Stock Units (RSUs) [Member]

Restricted Stock And Restricted Stock Unit Award Activity

Restricted stock unit activity for the years ended December 31, 2014 and 2013 is set forth below:

	Number of Shares		Weighted-Average Remaining Contractual Life (in Years)	Aggregate Intrinsic Value
Outstanding at January 1, 2013	115,466
Granted	38,375
Vested	(11,116	)
Canceled	(33,000	)
Outstanding at December 31, 2013	109,725
Granted	38,737
Vested	(19,598	)
Canceled	(25,940	)
Outstanding at December 31, 2014	102,924		2.1	$	6,381,288
Vested and expected to vest at December 31, 2014	79,445		1.9	$	4,925,584