Stock-Based Compensation Plans

3 Months Ended

Mar. 31, 2022

Share-based Payment Arrangement [Abstract]

Stock-Based Compensation Plans

Stock-Based Compensation Plans

Employee Stock Purchase Plan

Shares issued under the 2017 Employee Stock Purchase Plan during the three months ended March 31, 2022 and 2021, totaled 31,406 and 27,117, respectively.

Stock Options

A summary of stock option activity is as follows:

	Number of Shares	Weighted Average Exercise Price ($)		Weighted Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value of In-the-Money Options ($)
Outstanding as of December 31, 2021	1,640,319	$	18.42
Exercised	(57,083)	17.91
Outstanding as of March 31, 2022	1,583,236	$	18.44	3.12	$	20,657,176
Exercisable as of March 31, 2022	1,583,236	$	18.44	3.12	$	20,657,176

The total intrinsic value of stock options exercised during the three months ended March 31, 2022 and 2021, was $0.9 million and $3.1 million, respectively. There were no stock options granted during the three months ended March 31, 2022 or 2021.

Total Shareholder Return Awards

A summary of nonvested total shareholder return awards ("TSRs") is as follows:

	Number of Shares	Weighted Average Grant Date Fair Value
Nonvested as of December 31, 2021	1,154,721	$	40.10
Granted	520,020	42.99
Vested	(212,210)	45.86
Forfeited	(7,114)	43.22
Change in payout rate	(114,355)	45.92
Nonvested as of March 31, 2022	1,341,062	$	39.79

During the three months ended March 31, 2022, a total of 212,210 TSRs awards granted in fiscal 2019 vested and achieved a payout rate of 65% based on the Company's total shareholder return as compared to a group of peer companies over a three-

year performance period. The Company withheld 47,612 of those shares to pay the employees’ portion of the minimum payroll withholding taxes.

The fair value of TSRs granted during the three months ended March 31, 2022 and 2021, were estimated on the date of grant using the Monte Carlo simulation model, acceptable under ASC 718, Compensation - Stock Compensation, using the following weighted average assumptions:

	Three Months Ended March 31,
	2022		2021
Expected life (years)	3.1		2.8
Risk-free interest rate	1.5	%	0.3	%
Expected volatility	40.0	%	41.2	%
Expected dividend yield	—		—

Restricted Share Units

A summary of nonvested restricted share unit awards ("RSUs") is as follows:

	Number of Shares	Weighted Average Grant Date Fair Value
Nonvested as of December 31, 2021	946,151	$	33.57
Granted	756,517	31.69
Vested	(356,079)	31.72
Forfeited	(9,364)	33.38
Nonvested as of March 31, 2022	1,337,225	$	33.00

During the three months ended March 31, 2022, a total of 356,079 RSUs vested. The Company withheld 122,337 of those shares to pay the employees’ portion of the minimum payroll withholding taxes.

As of March 31, 2022, there were unrecognized compensation costs of $39.6 million and $36.1 million related to nonvested RSUs and TSRs, respectively, which the Company expects to recognize over weighted average periods of 2.4 years.

The Company recorded stock-based compensation expense recognized under ASC 718 for the three months ended March 31, 2022 and 2021, of $8.0 million and $6.7 million, respectively, with corresponding tax benefits of $1.1 million and $1.0 million, respectively.