18)

Stock-Based Compensation

Employee Stock Purchase Plans

The Company’s Fourth Restated 1999 Employee Stock Purchase Plan (the “Purchase Plan”) authorized the issuance of up to an aggregate of 1,950,000 shares of common stock to participating employees. Offerings under the Purchase Plan commenced on June 1 and December 1 and terminated, respectively, on November 30 and May 31. Under the Purchase Plan, eligible employees purchased shares of common stock through payroll deductions of up to 10% of their compensation or up to an annual maximum amount of $21,250. The price at which an employee’s purchase option was exercised was the lower of (1) 85% of the closing price of the common stock on the NASDAQ Global Select Market on the day that each offering commenced, or (2) 85% of the closing price on the day that each offering terminated. During 2014, the Company issued 69,474 shares of common stock to employees who participated in the Purchase Plan at an exercise price of $24.52 per share. As of June 1, 2014, the Purchase Plan was replaced by the 2014 Employee Stock Purchase Plan (the “2014 ESPP Plan”).

The Company’s Third Amended and Restated International Employee Stock Purchase Plan (the “Foreign Purchase Plan”) authorized the issuance of up to an aggregate of 400,000 shares of common stock to participating employees. Offerings under the Foreign Purchase Plan commenced on June 1 and December 1 and terminated, respectively, on November 30 and May 31. Under the Foreign Purchase Plan, eligible employees purchased shares of common stock through payroll deductions of up to 10% of their compensation or up to an annual maximum amount of $21,250. The price at which an employee’s purchase option was exercised was the lower of (1) 85% of the closing price of the common stock on the NASDAQ Global Select Market on the day that each offering commenced, or (2) 85% of the closing price on the day that each offering terminated. During 2014, the Company issued 20,053 shares of common stock to employees who participated in the Foreign Purchase Plan at an exercise price of $24.52 per share. As of June 1, 2014, the Foreign Purchase Plan was replaced by the 2014 ESPP Plan.

The 2014 ESPP Plan was adopted by the Board of Directors on February 10, 2014 and approved by the Company’s stockholders on May 5, 2014. The 2014 ESPP Plan authorizes the issuance of up to an aggregate of 2,500,000 shares of common stock to participating employees. Offerings under the 2014 ESPP Plan commence on June 1 and December 1 and terminate, respectively, on November 30 and May 31. Under the 2014 ESPP Plan, eligible employees may purchase shares of common stock through payroll deductions of up to 10% of their compensation or up to an annual maximum amount of $21,250. The price at which an employee’s purchase option is exercised is the lower of (1) 85% of the closing price of the common stock on the NASDAQ Global Select Market on the day that each offering commences, or (2) 85% of the closing price on the day that each offering terminates. During 2015 and 2014, the Company issued 140,531 and 82,481 shares, respectively, of common stock to employees who participated in the 2014 ESPP Plan at exercise prices of $30.74 and $31.34 per share in 2015 and $24.33 per share in 2014. As of December 31, 2015, there were 2,276,988 shares reserved for future issuance under the 2014 ESPP Plan.

Equity Incentive Plans

The Company has granted options to employees under the 2004 Stock Incentive Plan (the “2004 Plan”) and the Second Restated 1995 Stock Incentive Plan (the “1995 Plan”), and to directors under the 1997 Director Stock Plan (the “1997 Director Plan”); the Company has also granted restricted stock units (“RSUs”) to employees and directors under the 2004 Plan and the 2014 Stock Incentive Plan (the “2014 Plan” and together with the 2004 Plan, the 1995 Plan, and the 1997 Director Plan, the “Plans”). The Plans are administered by the Compensation Committee of the Company’s Board of Directors.

The Plans are intended to attract and retain employees and to provide an incentive for them to assist the Company to achieve long-range performance goals and to enable them to participate in the long-term growth of the Company. Employees may be granted RSUs, options to purchase shares of the Company’s stock and other equity incentives under the Plans.

The Company’s 2014 Plan was adopted by the Board of Directors on February 10, 2014 and approved by the Company’s stockholders on May 5, 2014. Up to 18,000,000 shares of common stock (subject to adjustment in the event of stock splits and other similar events) may be issued pursuant to awards granted under the 2014 Plan. The Company may grant options, RSUs, restricted stock appreciation rights and other stock-based awards to employees, officers, directors, consultants and advisors under the 2014 Plan. Any full-value awards granted under the 2014 Plan will be counted against the shares reserved for issuance under the 2014 Plan as 2.4 shares for each share of common stock subject to such award and any award granted under the 2014 Plan that is not a full-value award (including, without limitation, any option or SAR) will be counted against the shares reserved for issuance under the plan as one share for each one share of common stock subject to such award. “Full-value award” means any RSU, or other stock-based award with a per share price or per unit purchase price lower than 100% of fair market value on the date of grant. To the extent a share that was subject to an award that counted as one share is returned to the 2014 Plan, each applicable share reserve will be credited with one share. To the extent that a share that was subject to an award that counts as 2.4 shares is returned to the 2014 Plan, each applicable share reserve will be credited with 2.4 shares. As of December 31, 2015, there were 16,953,488 shares reserved for future issuance under the 2014 Plan.

The Company’s 2004 Plan expired in March 2014 and no further awards may be granted under the 2004 Plan, although there are still outstanding RSUs which may vest under the 2004 Plan. The Company’s 1995 Plan expired in November 2005 and no further awards may be granted under the 1995 Plan. The Company’s 1997 Director Plan expired in February 2007 and no further awards may be granted under the 1997 Director Plan.

Stock options were granted at an exercise price equal to 100% of the fair value of the Company’s common stock on the date of grant. Generally, stock options granted to employees under the 1995 Plan and the 2004 Plan from 2001 to 2006, vested 25% after one year and 6.25% per quarter thereafter, and expired 10 years after the grant date. Options granted to directors generally vested at the earliest of (1) one day prior to the next annual meeting, (2) 13 months from the date of grant, or (3) the effective date of an acquisition. There were no remaining outstanding stock options as of December 31, 2015 under any of the Plans. RSUs granted to employees in 2015, 2014 and 2013 generally vest 33.3% per year on the anniversary of the date of grant. RSUs granted to employees who are at least 60 years old and have a minimum of 10 Years of Service (as defined in the applicable RSU agreement) are expensed immediately. RSUs granted to directors generally vest at the earliest of (1) one day prior to the next annual meeting, (2) 13 months from date of grant, or (3) the effective date of an acquisition. Certain RSUs are subject to performance conditions (“performance shares”) under the Company’s 2004 Plan and 2014 Plan. Such performance shares are available, subject to time-based vesting conditions, if, and to the extent that, financial or operational performance criteria for the applicable period are achieved. Accordingly, the number of performance shares earned will vary based on the level of achievement of financial or operational performance objectives for the applicable period.

The following table presents the activity for RSUs under the Plans:


	Year Ended December 31,
	2015
	Non-vested RSUs			Weighted Average Grant Date Fair Value
Non-vested RSUs — beginning of period		716,714		$	28.67
Granted		394,952		$	32.89
Vested		(351,601	)	$	28.59
Forfeited or expired		(26,903	)	$	29.84

Non-vested RSUs — end of period		733,162		$	30.94

The following table presents the activity for options under the Plans:


	Year Ended December 31,
	2015
	Options			Weighted Average Exercise Price
Outstanding — beginning of period		30,224		$	19.67
Exercised		(30,100	)	$	19.68
Forfeited or expired		(124	)	$	18.16

Outstanding — end of period		—		$	—

Exercisable at end of period		—		$	—

There were no options outstanding or exercisable under the Plans at December 31, 2015.

The total cash received from employees as a result of employee stock option exercises during the years 2015 and 2014 was approximately $592 and $1,605, respectively. In connection with these exercises, the tax benefit realized by the Company for the years 2015 and 2014 was approximately $21 and $175, respectively.

The Company settles employee stock option exercises and restricted stock unit vesting with newly issued common shares.

Stock-Based Compensation Expense

The Company recognized the full impact of its share-based payment plans in the consolidated statements of operations and comprehensive income for the years 2015, 2014 and 2013. As of December 31, 2015 and 2014, the Company capitalized $471 of such cost on its consolidated balance sheet. The following table reflects the effect of recording stock-based compensation for the years 2015, 2014 and 2013:


	Years Ended December 31,
Stock-based compensation expense by type of award:	2015			2014			2013
Restricted stock units	$	11,885		$	10,203		$	12,982
Employee stock purchase plan		1,128			1,112			1,010

Total stock-based compensation		13,013			11,315			13,992
Tax effect on stock-based compensation		(836	)		(331	)		(495	)

Net effect on net income	$	12,177		$	10,984		$	13,497

Effect on net earnings per share:
Basic	$	0.23		$	0.21		$	0.25

Diluted	$	0.23		$	0.21		$	0.25

The pre-tax effect within the consolidated statements of operations and comprehensive income of recording stock-based compensation for the years 2015, 2014 and 2013 was as follows:


	Years Ended December 31,
	2015		2014		2013
Cost of revenues	$	1,814	$	1,960	$	2,038
Research and development expense		1,590		1,659		1,902
Selling, general and administrative expense		9,609		7,696		10,052

Total pre-tax stock-based compensation expense	$	13,013	$	11,315	$	13,992

Valuation Assumptions

The Company determines the fair value of restricted stock units based on the closing market price of the Company’s common stock on the date of the award, and estimates the fair value of stock options and employee stock purchase plan rights using the Black-Scholes valuation model. Such values are recognized as expense on a straight-line basis over the requisite service periods, net of estimated forfeitures except for retirement eligible employees in which the Company expenses the fair value of the grant in the period the grant is issued. The estimation of stock-based awards that will ultimately vest requires significant judgment. The Company considers many factors when estimating expected forfeitures, including types of awards and historical experience. Actual results, and future changes in estimates, may differ substantially from the Company’s current estimates.

The Company did not grant options during 2015, 2014 and 2013. The total intrinsic value of options exercised during 2015, 2014 and 2013 was approximately $494, $958 and $684, respectively.

The weighted average fair value per share of employee stock purchase plan rights granted in 2015, 2014 and 2013 was $8.16, $6.37 and $5.76, respectively. The fair value of the employees’ purchase plan rights was estimated using the Black-Scholes option-pricing model with the following weighted average assumptions:


	Years Ended December 31,
Employee stock purchase plan rights:	2015			2014			2013
Expected life (years)		0.5			0.5			0.5
Risk-free interest rate		0.1	%		0.1	%		0.1	%
Expected volatility		26.4	%		26.4	%		27.7	%
Expected annual dividends per share	$	0.675		$	0.655		$	0.64

Expected volatilities for 2015, 2014 and 2013 are based on a combination of implied and historical volatilities of the Company’s common stock; the expected life represents the weighted average period of time that options granted are expected to be outstanding giving consideration to vesting schedules and the Company’s historical exercise patterns; and the risk-free interest rate is based on the U.S. Treasury yield curve in effect at the time of grant for periods corresponding with the expected life of the option.

The total intrinsic value of options exercised and the total fair value of RSUs vested during 2015, 2014 and 2013 was approximately $12,868, $12,106 and $19,221, respectively. As of December 31, 2015, the unrecognized compensation cost related to restricted stock units was approximately $11,585 and will be recognized over an estimated weighted average amortization period of 0.82 years.