Stock-Based Compensation

12 Months Ended

Dec. 31, 2023

Share-Based Payment Arrangement [Abstract]

We have a long-term incentive plan (“LTIP”) that provides for the grant of various stock-based compensation awards at the discretion of our compensation committee of our board of directors. Employees and non-employee directors are eligible to receive awards under the LTIP. Stock-based awards granted pursuant to the LTIP are expected to be settled in shares of our Class A common stock if they vest. Our stock-based awards do not have voting rights prior to vesting. Dividends declared are accumulated and paid upon vesting. We account for forfeitures when they occur and recognize the impact to stock-based compensation expense at that time. We recorded $18.1 million, $10.6 million and $8.6 million of stock-based compensation expense for the years ended December 31, 2023, 2022 and 2021. Stock-based compensation expense is primarily recorded in selling, general and administrative expenses. We recognized $1.2 million, $1.7 million and $1.1 million in tax benefits for tax deductions from the vesting of stock-based awards benefits during the years ended December 31, 2023, 2022 and 2021, respectively. As of December 31, 2023, 3.0 million stock awards were available for grant.

Restricted Stock Units

Restricted stock units (“RSUs”) granted to our key employees generally vest over a three-year period (vesting ratably in equal tranches over a three-year period); however, RSUs granted to our non-employee directors generally vest on the first anniversary of the grant date. We recognize compensation expense over the requisite service period using straight-line amortization.

The following table summarizes our RSU activity during the year ended December 31, 2023 (RSUs in thousands):


	No. of RSUs	Weighted Average Grant Date Fair Value ($)
Nonvested as of December 31, 2022	350	$	36.27
Granted	484	43.19
Vested	(239)	31.57
Forfeited	(31)	44.43
Nonvested as of December 31, 2023	564	$	43.75

The weighted average grant date fair value of RSUs granted was $43.19 during 2023, $55.06 during 2022 and $32.92 during 2021. The total fair value of RSUs vested was $10.1 million during 2023, $14.1 million during 2022 and $13.9 million during 2021. There was approximately $16.7 million of unrecognized compensation expense relating to the unvested RSUs as of December 31, 2023. The unrecognized compensation expense will be recognized over the weighted average remaining vesting period of 2.3 years.

Performance Stock Units

Performance stock units (“PSUs”) are granted to our executive officers and in rare instances, other key employees. Under these awards, the number of shares vested and earned is typically determined at the end of a three-year performance period based on our Return on Capital Employed (“ROCE”). The number of shares earned may range from 0% to 200% of the target units set forth in the applicable award agreement and is determined at the end of the performance period conditioned upon continued service and on our achievement of certain predefined targets as defined in the underlying performance stock

unit agreements. PSUs cliff vest upon conclusion of the three-year performance period. As the ROCE target represents a performance condition, we recognize compensation expense for the performance share units on a straight-line basis over three years based on the probable outcome of the ROCE performance.

The following table summarizes our PSU activity during the year ended December 31, 2023 (PSUs in thousands at their target number of shares, which assumes achievement of 100% of target, unless otherwise noted):


	No. of PSUs	Weighted Average Grant Date Fair Value ($)
Nonvested as of December 31, 2022	128	$	43.63
Granted	149	44.20
Vested (1)	(131)	32.82
Forfeited	(35)	45.78
Performance adjustment (2)	65	32.82
Nonvested as of December 31, 2023	176	$	47.71

(1) Reflects shares vested at 200% of target based on actual ROCE performance upon conclusion of the three-year performance period.

(2) Represents additional shares issued to participants upon vesting due to the ROCE performance metrics exceeding target upon conclusion of the three-year performance period.

The weighted average grant date fair value of PSUs granted was $44.20 during 2023, $55.02 during 2022 and $32.82 during 2021. The total fair value of PSUs vested was $5.9 million during 2023 (200% of target achieved) and $4.8 million during 2022 (80% of target achieved). No PSUs vested during 2021. As of December 31, 2023, there was approximately $3.5 million of unrecognized compensation expense relating to the unvested PSUs (based on the grant date fair value of the awards at 100% of target) which is expected to be recognized over a weighted average period of 1.7 years.