Stock Options And Employee Stock Purchase Plan (Tables)

12 Months Ended

Dec. 31, 2013

Stock option activity for the years ended December 31, 2013, 2012 and 2011 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, 2010	3,794,394		$	14.40
Granted	163,319		$	29.42
Exercised	(1,820,678	)	$	7.92
Canceled	(49,340	)	$	24.76
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		$	21.21	4.0	$33,858,816
Exercisable at December 31, 2013	845,198		$	20.35	3.1	$25,068,917
Vested and expected to vest at December 31, 2013	1,132,886		$	21.01	3.9	$32,856,049

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, 2013:



	Options Outstanding				Exercisable Options
Range of Exercise Prices	Number Outstanding December 31, 2013	Weighted Average Remaining Contractual Life	Weighted Average Exercise Price		Number Exercisable December 31, 2013	Weighted Average Exercise Price
$9.55	200,000	0.23 years	$	9.55	200,000	$	9.55
13.74 - 15.65	7,911	0.93 years	15.57		7,911	15.57
17.19	150,420	5.18 years	17.19		43,280	17.19
18.77	172,925	1.67 years	18.77		172,925	18.77
20.15 - 21.67	157,504	4.86 years	21.21		130,152	21.15
21.88 - 23.11	119,228	6.13 years	22.85		65,244	22.78
23.40 - 29.34	203,169	6.52 years	28.25		94,686	28.32
29.53 - 31.07	47,500	8.00 years	30.26		14,000	30.52
32.45	102,000	3.59 years	32.45		102,000	32.45
34.73	15,000	3.56 years	34.73		15,000	34.73
$9.55 - $34.73	1,175,657	4.03 years	$	21.21	845,198	$	20.35

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	2011
Risk-free interest rate		1.1%	2.3%
Expected term (in years)		5.7	6.5
Dividend yield		3.2%	2.6%
Expected volatility		41.6%	41.8%

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, 2013, 2012 and 2011 (in thousands):



	Year Ended December 31,
	2013		2012		2011
Cost of revenues	$	756	$	844	$	982
Operating expenses:
Sales and marketing	1,855		1,543		1,431
Research, development and engineering	434		459		477
General and administrative	6,675		6,286		6,103
	$	9,720	$	9,132	$	8,993

Restricted Stock [Member]

Restricted Stock And Restricted Stock Unit Award Activity

Restricted stock award activity for the year ended December 31, 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

Restricted Stock Units (RSUs) [Member]

Restricted Stock And Restricted Stock Unit Award Activity

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



	Number of Shares		Weighted-Average Remaining Contractual Life (in Years)	Aggregate Intrinsic Value
Outstanding at January 1, 2012	32,750
Granted	91,166
Vested	(1,700	)
Canceled	(6,750	)
Outstanding at December 31, 2012	115,466
Granted	38,375
Vested	(11,116	)
Canceled	(33,000	)
Outstanding at December 31, 2013	109,725		2.2	$	5,487,347
Vested and expected to vest at December 31, 2013	74,509		1.9	$	3,726,174