Stock-Based Compensation

3 Months Ended

Mar. 31, 2023

Share-Based Payment Arrangement [Abstract]

Aggregate stock-based compensation charges were $7.0 million and $8.3 million during the three months ended March 31, 2023 and 2022, respectively. Routine stock-based compensation expense is included as a component of “Selling, general and administrative” expense on the accompanying Condensed Consolidated Statements of Operations. As of March 31, 2023, there was $41.6 million of unrecognized stock-based compensation expense related to stock options and restricted stock units, which will be recognized over a weighted-average period of 2.3 years.

Restricted Stock Units Activity

The following table provides a summary of restricted stock unit (RSU) activity for the three months ended March 31, 2023:


Three Months Ended March 31, 2023
	Number of Time-Based RSUs	Aggregate Intrinsic Value (in millions)		Number of Market Performance-Based RSUs(2)	Aggregate Intrinsic Value (in millions)
Non-vested as of December 31, 2022	687,667	$	19.5	249,447	$	7.1
Granted	406,062			107,177
Market-performance adjustment(3)	—			(10,834)
Vested	(181,204)			(52,962)
Forfeited	(18,261)			(6,477)
Non-vested as of March 31, 2023	894,264	$	25.4	286,351	$	8.1
Shares vested, but not released(1)	46,890	$	1.3	—	$	—
Total outstanding restricted stock units	941,154	$	26.7	286,351	$	8.1

(1)For certain vested RSUs, common stock issuance is contingent upon the first to occur of: (1) termination of service; (2) change in control; (3) death; or (4) disability, as defined in the 2010 Plan. These 46,890 RSUs belong to an active member of the Board of Directors and the date of issuance is therefore unknown at this time. The weighted average grant date fair value of these units is $8.42 per unit.

(2)The number of market performance-based RSUs are reflected within this table based upon the number of shares of common stock issuable upon achievement of the performance metric at target.

(3)Represents the decrease in the number of original market-performance units awarded based on the final performance criteria achievement at the end of the defined performance period. In January 2023, following the completion of the applicable market-performance period, the Compensation Committee determined that the 47th percentile had been achieved for the 2020 awards and, accordingly, 52,962 units vested immediately, representing a vesting percentage of 83.0%.


Three Months Ended March 31, 2022
Restricted Stock	Number of Time-Based Restricted Stock Units	Aggregate Intrinsic Value (in millions)		Number of Performance-Based Restricted Stock Units	Aggregate Intrinsic Value (in millions)		Number of Market Performance-Based Restricted Stock Units(2)	Aggregate Intrinsic Value (in millions)
Non-vested as of December 31, 2021	1,071,959	$	35.1	—	$	—	374,048	$	12.3
Granted	350,641			—			130,458
Market-performance adjustment(3)	—			—			(18,253)
Vested	(171,176)			—			(194,111)
Forfeited	(45,597)			—			(8,044)
Non-vested as of March 31, 2022	1,205,827	$	33.6	—	$	—	284,098	$	7.9
Shares vested, but not released(1)	615,643	17.2		42,856	1.2		—	—
Total outstanding restricted stock units	1,821,470	$	50.8	42,856	$	1.2	284,098	$	7.9

(1)For certain vested restricted stock units, common share issuance is contingent upon the first to occur of: (1) termination of service; (2) change in control; (3) death; or (4) disability, as defined in the 2010 Plan. This is comprised of 568,753 vested time-based restricted stock units which belong to a member of the Board of Trustees who has resigned and common shares shall not be issued until the first to occur: (1) change in control; or (2) April 13, 2022. The weighted average grant date fair value of these units is $9.38 per unit. This is also comprised of 46,890 vested time-based restricted stock units which belong to an active member of the Board of Trustees and the date of issuance is therefore unknown at this time. The weighted average grant date fair value of these units is $8.42 per unit. Finally, this is comprised of 42,856 vested performance-based restricted stock units which belong to the former CEO and common shares shall not be issued until May 2, 2022 in accordance with the terms of the award. The weighted average grant date fair value of these units is $13.43 per unit. The holders of these vested restricted stock units are entitled to receive distributions, but are not entitled to vote the shares until common shares are issued.in exchange for these vested restricted stock units.

(2)The number of market performance-based restricted stock units are reflected within this table based upon the number of shares issuable upon achievement of the performance metric at target.

(3)Represents the decrease in the number of original market-performance units awarded based on the final performance criteria achievement at the end of the defined performance period.

The weighted average grant date fair value of restricted stock units granted during the three months ended March 31, 2023 was $31.03 per unit. During the three months ended March 31, 2023, the weighted average grant date fair value of vested and converted restricted stock units was $29.58 and forfeited restricted stock units was $28.16. The weighted average grant date fair value of non-vested restricted stock units was $29.07 and $28.15 per unit as of March 31, 2023 and December 31, 2022, respectively.

OP Units Activity

The following table provides a summary of the OP unit activity for the three months ended March 31, 2023:


Three Months Ended March 31, 2023
	Number of Time-Based OP Units	Aggregate Intrinsic Value (in millions)		Number of Market Performance-Based OP Units	Aggregate Intrinsic Value (in millions)
Non-vested as of December 31, 2022	160,182	$	4.5	462,815	$	13.1
Granted	127,637			193,560
Market-performance adjustment(1)	—			(23,959)
Vested	(53,498)			(116,983)

Non-vested as of March 31, 2023	234,321	$	6.7	515,433	$	14.7
Shares vested, but not released	228,456	$	6.5	—	$	—
Total outstanding OP units	462,777	$	13.2	515,433	$	14.7

(1) Represents the decrease in the number of original market-performance units awarded based on the final performance criteria achievement at the end of the defined performance period. In January 2023, following the completion of the applicable market-performance period, the Compensation Committee determined that the 47th percentile had been achieved for the 2020 awards and, accordingly, 116,983 units vested immediately, representing a vesting percentage of 83.0%.


Three Months Ended March 31, 2022
OP Units	Number of Time-Based OP Units	Aggregate Intrinsic Value (in millions)		Number of Market Performance-Based OP Units	Aggregate Intrinsic Value (in millions)
Non-vested as of December 31, 2021	140,222	$	4.6	288,165	$	9.4
Granted	98,994			243,986
Vested	(28,179)			—
Forfeited	(7,635)			(20,366)
Non-vested as of March 31, 2022	203,402	$	5.7	511,785	$	14.3
Shares vested, but not released	104,874	2.9		—	—
Total outstanding OP units	308,276	$	8.6	511,785	$	14.3

The weighted average grant date fair value of OP units granted during the three months ended March 31, 2023 was $33.52 per unit. During the three months ended March 31, 2023, the weighted average grant date fair value of vested OP units was $29.60. The weighted average grant date fair value of non-vested OP units was $30.61 and $29.39 per unit as of March 31, 2023 and December 31, 2022, respectively.

Stock Options Activity

The following table provides a summary of stock option activity for the three months ended March 31, 2023:


Options	Number of Options	Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Terms (Years)
Outstanding as of December 31, 2022	105,498	$	9.81	3.6
Granted	—	$	—
Exercised	—	$	9.81
Forfeited or expired	—	$	—
Outstanding as of March 31, 2023	105,498	$	9.81	3.4

Exercisable as of March 31, 2023	105,498	$	9.81	3.4


Options	Shares (In thousands)	Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Terms (Years)
Outstanding as of December 31, 2021	206,298	$	9.81	2.9
Granted	—	—
Exercised	(40,900)	9.81
Forfeited or expired	—	—
Outstanding as of March 31, 2022	165,398	9.81		3.1

Exercisable as of March 31, 2022	165,398	$	9.81	3.1

All outstanding stock options were vested as of December 31, 2022.