The Company recognizes compensation cost related to share-based payment transactions in the financial statements based on the fair value of the equity or liability instruments issued. Compensation expense related to the fair value of share-based awards is recognized over the requisite service period. Over the life of the grant, the estimate of share-based compensation expense for awards with performance and/or service requirements is adjusted so that compensation cost is recognized only for awards that ultimately vest; for the grants with market conditions, the fair value of the award is determined at grant date and expensed over the life of the grant.

The Company has stock compensation plans pursuant to which it is authorized to grant stock-based awards of which 2.1 million shares of the Company's common stock remain available for grant as of December 31, 2021. The Company’s policy allows the issuance of new or treasury shares to satisfy stock-based awards. Restricted stock, stock options, stock appreciation rights and performance share awards may be granted to officers, key employees and non-employee directors with contractual terms set by the Compensation and Management Development Committee of the Board of Directors.

The Company granted approximately 0.3 million, 0.2 million and 0.1 million options to certain employees of the Company at a fair value of approximately $7.9 million, $2.7 million and $2.2 million during the years ended December 31, 2021, 2020 and 2019, respectively. The stock options granted by the Company had an exercise price equal to the market price of the Company’s common stock on the date of grant. The fair value of the options granted was estimated on the grant date using the Black-Scholes option-pricing model with the following weighted average assumptions:


	2021			2020			2019
Risk-free interest rate	0.94		%	0.99		%	2.46		%
Expected volatility	29.23		%	20.88		%	21.49		%
Expected life of stock option	5.9 years			5.9 years			4.4 years
Dividend yield	0.82		%	0.99		%	1.06		%
Requisite service period	4 years			4 years			4 years
Contractual life	10 years			10 years			7 years
Weighted average fair value of options granted (per option)	$	28.00		$	17.25		$	15.84

The expected life of the options and volatility are based on the historical data which is believed to be indicative of future exercise patterns and volatility. Historical volatility is calculated based on a period that corresponds to the expected life of the stock option. The dividend yield and the risk-free rate of return are calculated on the grant date based on the then current dividend rate and the risk-free rate for the period corresponding to the expected life of the stock option. Compensation expense related to the fair value of these awards is recognized straight-line over the requisite service period based on those awards that ultimately vest.

The aggregate intrinsic value of stock options outstanding and exercisable as of December 31, 2021 was $66.4 million and $37.5 million, respectively. The total intrinsic value of options exercised during the years ended December 31, 2021, 2020 and 2019 was $10.6 million, $8.9 million and $15.8 million, respectively.

The Company received $11.1 million, $10.2 million and $21.4 million in proceeds from the exercise of 0.2 million, 0.2 million and 0.4 million employee stock options during the years ended December 31, 2021, 2020 and 2019, respectively.


	Options Outstanding				Options Exercisable
Range of Exercise Prices	Number Outstanding at December 31, 2021	Weighted Average Remaining Contractual Life (Years)	Weighted Average Exercise Price		Number Exercisable at December 31, 2021	Weighted Average Exercise Price
$45.59 to $55.00	156,462	1.16	$	51.49	156,462	$	51.49
$55.01 to $65.00	84,038	2.10	60.86		84,038	60.86
$65.01 to $85.00	239,981	3.75	81.31		142,673	81.35
$85.01 to $91.28	153,692	8.17	91.28		38,419	91.28
$91.29 to $104.87	276,771	9.16	104.87		—	—
	910,944	5.54	$	83.14	421,592	$	67.09


	For the Year Ended December 31,
	2021		2020		2019
Restricted shares granted	61,009		158,133		167,731
Weighted average grant date fair value per share	$	111.25	$	90.18	$	81.92
Aggregate grant date fair value (in thousands)	$	6,787	$	14,260	$	13,741
Restricted shares forfeited	19,209		36,860		32,735
Vesting service period of shares granted	9 - 48 months		12 - 48 months		12 - 48 months
Fair value of shares vested (in thousands)	$	11,927	$	9,000	$	10,671

Compensation expense related to the fair value of these awards is recognized straight-line over the requisite service period based on those restricted stock grants that ultimately vest. The fair value of grants is measured by the market price of the Company’s common stock on the date of grant. Restricted stock awards generally vest ratably over the service period beginning with the first anniversary of the grant date. Awards granted to retirement eligible non-employee directors are recognized over the shorter of the requisite service period or the length of time until retirement since the terms of the grant provide that awards will vest upon retirement.

The Company has granted performance vested restricted stock units (“PVRSU”) to certain employees. The Company grants three types of PVRSU awards: i) PVRSUs with performance conditions based on internal performance metrics, ii) PVRSUs with market conditions based on the Company's total shareholder return ("TSR") relative to a predetermined peer group, and iii) PVRSUs with both performance and market conditions. The vesting of PVRSU awards is contingent upon the Company achieving internal performance and/or TSR targets over a specified period and the employees' continued employment for a service period. These performance and market conditions affect the number of shares that will ultimately vest.

During the year ended December 31, 2021, the Company granted PVRSUs with market conditions, PVRSUs with performance conditions and PVRSUs with performance and market conditions with requisite service periods between 9 months and 60 months with award vesting ranges generally between 0% and 300% of the initial units granted.

The fair value of PVRSUs with only internal performance metrics is measured by the market price of the Company's common stock on the date of award grant. Compensation expense is recognized ratably over the requisite service period based on the Company's estimate of the achievement of the performance conditions. Management monitors current results and forecasts of the relevant internal performance metrics and, as necessary, adjusts the performance-based leveraging of unvested PVRSUs.

The fair value of PVRSUs with market conditions is estimated using a Monte Carlo simulation method as of the date of award grant. Compensation expense is recognized ratably over the requisite service period, regardless of whether the market conditions are achieved and the awards ultimately vest.

The fair value of PVRSUs with both performance and market conditions is estimated using a Monte Carlo simulation as of the date of award grant. Compensation is recognized ratable over the requisite service period based on the Company's estimate of the achievement of the performance conditions, with subsequent adjustments made for performance-based leveraging of unvested PVRSUs, as necessary.

The Company has currently estimated that between 0% and 300% of the various award targets will be achieved. During the year ended December 31, 2020, the Company reduced the leveraging factor for 230,647 unvested PVRSUs granted in the current and prior periods to 0%, based on management's estimate of achievement of performance targets with contemplation to impacts from the COVID-19 pandemic.


	For the Years Ended December 31,
	2021		2020		2019
PVRSUs granted at target	98,544		170,471		83,934
Weighted average grant date fair value per share	$	108.75	$	134.26	$	81.15
Aggregate grant date fair value (in thousands)	$	10,716	$	22,888	$	6,811
PVRSUs forfeited & expired	78,500		33,080		18,379
Requisite service period	9 - 60 months		31 to 36 months		36 to 48 months

During the years ended December 31, 2021, 2020 and 2019, PVRSUs totaling 3,986, 176,471 and 73,242, respectively, vested at a fair value of $0.3 million, $17.5 million, and $5.5 million, respectively. During the year ended December 31, 2021, an additional 920 units were awarded because the Company's performance exceeded the conditions provided in the awards. During the year ended December 31, 2020, an additional 30,116 units were awarded because the Company's performance exceeded the conditions provided in the awards. During the year ended December 31, 2019, an additional 1,583 units were awarded because the Company's performance exceeded the conditions provided in the awards.

As a result of the Company's operating results not achieving certain performance conditions contained in the PVRSU awards, the number of PVRSUs that expired was 72,944 shares for the year ended December 31, 2021, 16,117 shares for the year ended December 31, 2020, and no shares for the year ended December 31, 2019.


	2021
	Stock Options				Restricted Stock			Performance Vested Restricted Stock Units
	Options	Weighted Average Exercise Price		Weighted Average Remaining Contractual Life	Shares	Weighted Average Grant Date Fair Value		Shares	Weighted Average Grant Date Fair Value
Outstanding as of January 1, 2021	819,610	$	70.48		304,439	$	84.48	321,752	$	109.25
Granted	280,811	104.87			61,009	111.25		98,544	108.75
Performance-based leveraging*	—	—			—	—		74,832	107.51
Exercised/vested	(185,437)	59.61			(109,640)	80.83		(3,986)	81.55
Expired	—	—			—	—		(72,944)	81.55
Forfeited	(4,040)	104.87			(19,209)	90.23		(5,556)	55.76
Outstanding as of December 31, 2021	910,944	$	83.14	5.5 years	236,599	$	92.60	412,642	$	114.70
Options exercisable as of December 31, 2021	421,592	$	67.09	2.8 years


	2020
	Stock Options				Restricted Stock			Performance Vested Restricted Stock Units
	Options	Weighted Average Exercise Price		Weighted Average Remaining Contractual Life	Shares	Weighted Average Grant Date Fair Value		Shares	Weighted Average Grant Date Fair Value
Outstanding as of January 1, 2020	873,895	$	61.69		312,097	$	75.23	330,716	$	70.03
Granted	158,620	91.28			158,133	90.18		170,471	134.26

Performance-based leveraging*	—	—			—	—		30,116	60.68
Exercised/vested	(209,209)	49.17			(128,931)	69.80		(176,471)	58.68
Expired	—	—			—	—		(16,117)	60.50
Forfeited	(3,696)	91.28			(36,860)	81.98		(16,963)	82.25
Outstanding as of December 31, 2020	819,610	$	70.48	4.2 years	304,439	$	84.48	321,752	$	109.25
Options exercisable as of December 31, 2020	480,255	$	60.70	2.5 years


	2019
	Stock Options				Restricted Stock			Performance Vested Restricted Stock Units
	Options	Weighted Average Exercise Price		Weighted Average Remaining Contractual Life	Shares	Weighted Average Grant Date Fair Value		Shares	Weighted Average Grant Date Fair Value
Outstanding as of January 1, 2019	1,186,180	$	54.13		303,765	$	65.06	336,820	$	63.28
Granted	141,827	81.15			167,731	81.92		83,934	81.15
Performance-based leveraging*	—	—			—	—		1,583	51.49
Exercised/vested	(446,456)	47.96			(126,664)	60.39		(73,242)	50.69
Expired	—	—			—	—		—	—
Forfeited	(7,656)	51.49			(32,735)	72.54		(18,379)	72.50
Outstanding as of December 31, 2019	873,895	$	61.69	3.5 years	312,097	$	75.23	330,716	$	70.03
Options exercisable as of December 31, 2019	513,924	$	55.10	2.6 years


	For the Year Ended December 31,
(in thousands)	2021		2020		2019
Stock options	$	3,396	$	1,975	$	2,194
Restricted stock	9,281		8,731		8,043
Performance vested restricted stock units	10,703		(3,466)		6,409
Total share-based compensation expense	$	23,380	$	7,241	$	16,646
Income tax benefit	$	5,648	$	1,706	$	4,010

The total unrecognized compensation costs related to stock-based awards that have not yet vested and the related weighted average amortization period over which the costs are to be recognized as of December 31, 2021 are as follows:


(in thousands)	Unrecognized Compensation Expense on Unvested Awards		Weighted Average Remaining Amortization Period
Stock options	$	8,050	2.8 years
Restricted stock	13,976		2.1 years
Performance vested restricted stock units	25,973		1.4 years
Total	$	47,999

During the fourth quarter of 2021, the Company's board of directors announced a 6% increase to the quarterly dividend rate to $0.2375 per share from $0.225 per share, beginning with the dividend payable in the first quarter of 2022.

During the fourth quarter of 2019, the Company's board of directors announced a 5% increase to the quarterly dividend rate to $0.225 per share from $0.215 per share, beginning with the dividend payable in the first quarter of 2020. On February 28, 2020, the Company’s board of directors declared a quarterly cash dividend of $0.225 per share of common stock for $12.5 million. The dividend was payable on April 16, 2020 to shareholders of record on April 2, 2020. Subsequent to the payment of the dividend, in light of uncertainty resulting from the COVID-19 pandemic, the Company’s board of directors suspended future, undeclared dividends while the pandemic is significantly impacting travel.

On May 7, 2021, the Company's board of directors declared a quarterly cash dividend of $0.225 per share of common stock and approved resumption of the share repurchase program. Additionally, on September 9, 2021, the Company's board of directors declared a quarterly cash dividend of $0.225 per share of common stock.

During the year ended December 31, 2021, the Company's quarterly dividend rate was $0.225 per share for the second and third quarter and was $0.2375 per share in the fourth quarter of 2021. Annual dividends declared during the year ended December 31, 2021 were $0.688 per share or $38.2 million. During the year ended December 31, 2020, the Company's quarterly dividend rate was $0.225 per share. Annual dividends declared during the year ended December 31, 2020 were $0.225 per share or $12.5 million. During the year ended December 31, 2019, the Company's quarterly dividend rate was $0.215 per share for the first three quarters and was $0.225 per share in the fourth quarter of 2019. Annual dividends declared during the year ended December 31, 2019 were $0.87 per share or $48.5 million.

In addition, during the years ended December 31, 2021, 2020 and 2019, the Company paid previously declared but unrecorded dividends totaling $8 thousand, $0.4 million, and $0.2 million, respectively, that were contingent upon the vesting of performance vested restricted units.

During the year ended December 31, 2019, the Company repurchased 0.6 million shares of its common stock under the repurchase program at a total cost of $44.1 million. During the three months ended March 31, 2020, the Company repurchased 0.5 million shares of common stock under the share repurchase program at a total cost of $43.3 million. In light of uncertainty resulting from the COVID-19 pandemic, the Company subsequently temporarily suspended activity under the share repurchase program and no additional repurchases were made pursuant to the program for the balance of 2020. On May 7, 2021, the Company's board of directors approved resumption of the share repurchase program. During the year ended December 31, 2021, the Company repurchased 57,754 shares of its common stock under the repurchase program at a total cost of $7.3 million. On a cumulative basis through December 31, 2021, the Company repurchased 51.7 million shares of its common stock (including 33.0 million prior to the two-for-one stock split effected in October 2005) under the share repurchase program at a total cost of $1.5 billion.

During 2021, the Company redeemed 54,441 shares of common stock at a total cost of approximately $6.0 million from employees to satisfy the option exercise price and statutory minimum tax-withholding requirements related to the exercising of stock options and vesting of performance vested restricted stock units and restricted stock grants. During 2020 and 2019, the Company redeemed 0.1 million and 79,603 shares of common stock at a total cost of $12.2 million and $6.5 million, respectively, from employees to satisfy the option price and minimum tax-withholding requirements related to the exercising of