On April 4, 2018, the Company’s board of directors approved the 2018 Omnibus Incentive Plan (the “2018 Omnibus Plan”), which was subsequently approved by the stockholders and became effective on May 31, 2018 (the “Effective Date”). The 2018 Omnibus Plan replaced the previous 2010 Omnibus Incentive Plan (the “Prior Plan”).

On or after the Effective Date, the 2018 Omnibus Plan allows the Company to grant 1,185,000 shares using stock options, stock appreciation rights, restricted stock, RSUs, performance units and PSAs, cash-based awards, and other stock-based awards to all key officers, key employees, and non-employee directors of the Company. Outstanding grants under the Prior Plan, totaling 568,801, remain subject to their terms and conditions, and no additional awards from the Prior Plan are to be made after the Effective Date. As of December 31, 2018, the Company had approximately 1,098,906 shares available to grant under the 2018 Omnibus Plan. CSRSUs have no impact on the shares available for grant under the 2018 Omnibus Plan and have no impact on the calculated shares used in earnings per share calculations.

The total stock-based compensation expense for the years ended December 31, 2018, 2017, and 2016, the unrecognized compensation expense at December 31, 2018, and the weighted-average period to recognize the remaining unrecognized shares are as follows:

	Stock-Based Compensation Expense
	Recognized as of December 31,						Unrecognized
	2018		2017		2016		December 31, 2018		Weighted-Average Period to Recognize (years)
Stock Options	$	—	$	164	$	909	$	—		—
Restricted Stock Units		7,410		7,080		6,325		13,484		1.8
Cash-Settled Restricted Stock Units		8,214		7,253		7,091		10,550		1.6
Non-Employee Director Awards		764		671		741		327		0.4
Performance Shares		3,193		2,376		877		3,000		1.5
Total	$	19,581	$	17,544	$	15,943	$	27,361

The assumptions of employment termination forfeiture rates used in the determination of fair value of stock awards during the 2018 calendar year were based on the Company’s historical average of actual forfeitures from the previous 5 years preceding the reporting period. The expected annualized forfeiture rates used during the 2018 calendar year varied from 0% to 18.17%, and the Company does not expect these termination rates to vary significantly in the future.

Option awards are granted with an exercise price equal to the market value of the Company’s common stock on the date of grant. All options outstanding as of December 31, 2018 have a 10-year contractual term. Options generally have a vesting term of three or four years. There were no option awards granted during 2018, 2017, and 2016.

	Number of Shares			Weighted Average Exercise Price		Aggregate Intrinsic Value
Outstanding at January 1, 2016		723,005		$	28.62
Exercised		(128,301	)	$	23.65
Granted	—			$	—
Forfeited/Expired		(7,297	)	$	40.68
Outstanding at December 31, 2016		587,407		$	29.56
Exercised		(175,909	)	$	26.84
Granted		—		$	—
Forfeited/Expired		—		$	—
Outstanding at December 31, 2017		411,498		$	30.71
Exercised		(209,688	)	$	27.86
Granted		—		$	—
Forfeited/Expired		—		$	—
Outstanding at December 31, 2018		201,810		$	33.68	$	6,276,432

Vested plus expected to vest at December 31, 2018		201,810		$	33.68	$	6,276,432
Exercisable at December 31, 2018		201,810		$	33.68	$	6,276,432

The aggregate intrinsic value in the preceding table is based on the Company’s closing stock price of $64.78 as of December 31, 2018. The total intrinsic value of options exercised was $8.3 million, $4.5 million, and $2.5 million for the years ended December 31, 2018, 2017, and 2016, respectively. The fair value of shares vested was $0, $1.9 million, and $1.3 million for the years ended December 31, 2018, 2017, and 2016, respectively. As of December 31, 2018, the weighted-average remaining contractual term for options vested was 4.7 years and for exercisable options was 4.7 years.

Information regarding stock options outstanding as of December 31, 2018 is summarized below:

	OPTIONS OUTSTANDING						OPTIONS EXERCISABLE
Range of Exercise Prices	Number Outstanding As of December 31, 2018		Weighted Average Remaining Contractual Term		Weighted Average Exercise Price		Number Exercisable As of December 31, 2018		Weighted Average Exercise Price
$21.77 to $25.00		1,915		2.3	$	21.77		1,915	$	21.77
$25.01 to $28.00		100,114		4.1	$	26.93		100,114	$	26.93
$28.01 to $40.68		99,781		5.2	$	40.68		99,781	$	40.68
$21.77 to $41.00		201,810		4.7	$	33.68		201,810	$	33.68

RSUs generally have a vesting term of three to four years. On vesting the employee is issued one share of stock for each RSU awarded. The fair value of shares vested was $6.5 million, $6.3 million, and $7.2 million for the years ended December 31, 2018, 2017, and 2016, respectively.

	Number of Shares			Weighted- Average Grant Date Fair Value		Aggregate Intrinsic Value
Non-vested RSUs at January 1, 2016		555,904		$	35.40
Granted		240,868		$	34.68
Vested		(221,659	)	$	32.45
Cancelled		(67,115	)	$	37.60
Non-vested RSUs at December 31, 2016		507,998		$	36.12
Granted		194,227		$	41.41
Vested		(179,974	)	$	35.19
Cancelled		(58,664	)	$	36.04
Non-vested RSUs at December 31, 2017		463,587		$	38.71
Granted		235,480		$	65.37
Vested		(169,279	)	$	38.66
Cancelled		(54,742	)	$	47.50
Non-vested RSUs at December 31, 2018		475,046		$	50.93	$	30,773,480
RSUs expected to vest in the future		425,272		$	49.77	$	27,549,127

The aggregate intrinsic value in the preceding table is based on the Company’s closing stock price of $64.78 per share as of December 31, 2018.

CSRSUs generally have a vesting term of three to four years. A summary of the Company’s CSRSUs is presented below.

	Number of Shares			Weighted- Average Grant Date Fair Value		Aggregate Intrinsic Value
Non-vested CSRSUs at January 1, 2016		446,663		$	37.18
Granted		233,790		$	34.29
Vested		(146,619	)	$	34.70
Cancelled		(70,812	)	$	37.55
Non-vested CSRSUs at December 31, 2016		463,022		$	35.96
Granted		174,419		$	42.06
Vested		(161,576	)	$	40.78
Cancelled		(83,949	)	$	36.43
Non-vested CSRSUs at December 31, 2017		391,916		$	38.80
Granted		147,103		$	60.84
Vested		(147,759	)	$	38.71
Cancelled		(51,695	)	$	43.07
Non-vested CSRSUs at December 31, 2018		339,565		$	47.73	$	21,997,021
CSRSUs expected to vest in the future		301,532		$	47.00	$	19,533,238

The aggregate intrinsic value in the preceding table is based on the Company’s closing stock price of $64.78 per share as of December 31, 2018. The fair value of CSRSUs vested and settled in cash for the years ended December 31, 2018, 2017, and 2016 was $7.7 million, $6.9 million and $5.9 million, respectively.

In the first six months of 2018, the Company granted awards of unregistered shares to its non-employee directors on a quarterly basis under its Annual Equity Election. The awards were issued from the Company’s treasury stock and had no impact on the shares available for grant under the 2018 Omnibus Plan or the Prior Plan. The awards do not include vesting conditions; thus, there was no unrecognized expense related to these awards at December 31, 2018.

A summary of the Company’s non-employee director awards of unregistered shares granted by fiscal year is presented below.

For the Year ended December 31,	Number of shares Granted		Weighted- Average Grant Date Fair Value
2016		15,299	$	39.32
2017		13,861	$	48.41
2018		7,985	$	60.36

On July 2, 2018, the Company granted awards of registered shares to its non-employee directors on an annual basis under the Omnibus Plan. A summary of the non-employee director awards is presented below:

	Number of Shares			Weighted-Average Grant Date Fair Value		Aggregate Intrinsic Value
Non-vested RSAs at January 1, 2018		—		$	—
Granted		11,606		$	72.35
Vested		(5,395	)	$	72.35
Cancelled		(1,243	)	$	72.35
Non-vested RSAs at December 31, 2018		4,968		$	72.35	$	321,827
RSAs expected to vest in the future		4,968		$	72.35	$	321,827

The aggregate intrinsic value in the preceding table is based on the Company’s closing stock price of $64.78 per share as of December 31, 2018.

In the first quarter of 2015, the Company’s Board of Directors approved a performance-based share program (the “Program”) that provides for the issuance of PSAs to its senior management. Under the Program, the number of PSAs that the participant will receive depends on the Company’s achievement of two performance goals during two performance periods. The performance goals under the Program are based on (i) the Company’s compounded annual growth rate in earnings per share (“EPS”) during a two-year performance period and (ii) the Company’s cumulative total shareholder return (“rTSR”) relative to its peer group during a performance period from the first day of the performance period (typically January 1 of the year awarded) to the last day of the third year of the performance period (typically December 31). The PSAs will only be eligible to vest following the expiration of the three-year performance period. Actual shares vested will be subject to both continued employment by the Company (barring certain exceptions allowing for partial performance periods) and actual financial measures achieved. The actual number of shares of common stock that will be issued to each participant at the end of the applicable performance period will be determined by multiplying the award by the product of two percentages, one based on the Company’s EPS performance and a second one based on the Company’s rTSR performance, subject to a minimum and maximum performance level. As of December 31, 2018, shares granted during 2016, 2017, and 2018 are within year three, two, and one of the performance period, respectively, and therefore have not vested. A total of 30,576 shares granted in 2015 vested during 2018 after meeting the performance goals.

	Number of Shares			Weighted-Average Grant Date Fair Value		Aggregate Intrinsic Value
Non-vested PSAs at January 1, 2016		58,822		$	44.21
Granted		74,574		$	37.75
Vested		—		$	—
Cancelled		(3,422	)	$	41.61
Non-vested PSAs at December 31, 2016		129,974		$	40.57
Granted		60,929		$	38.81
Vested		—		$	—
Cancelled		(3,881	)	$	42.83
Non-vested PSAs at December 31, 2017		187,022		$	39.95
Granted		45,136		$	65.05
Vested		(30,576	)	$	44.21
Cancelled		(32,096	)	$	43.72
Non-vested PSAs at December 31, 2018		169,486		$	45.15	$	10,979,303
PSAs expected to vest in the future		97,309		$	50.35	$	6,303,674

The aggregate intrinsic value in the preceding table is based on the Company’s closing stock price of $64.78 per share as of December 31, 2018. The fair value of the awards is estimated on the grant date using a Monte Carlo simulation model due to the market condition for the rTSR component. The fair value assumptions using the Monte Carlo simulation model for awards granted in 2018, 2017, and 2016 were 0.9%, 0.0% and 0.0% for dividend yields, respectively; 31.9%, 31.3% and 30.9% for historical volatility, respectively; and 2.4%, 1.5%, and 1.0% both risk-free rate of returns, respectively.