Stock-Based Compensation

6 Months Ended

Jun. 30, 2022

Share-Based Payment Arrangement [Abstract]

The Company's stock-based compensation expense for the three and six months ended June 30, 2022 and 2021 included PRSUs, non-qualified stock options, RSUs and deferred stock units ("DSUs"). A summary of the Company's stock-based compensation expense is presented in the following table:


	Three Months Ended June 30,				Six Months Ended June 30,
(in millions)	2022		2021		2022		2021
PRSU expense	$	7.9	$	9.7	$	16.2	$	19.3
Option expense	—		0.4		—		0.8
RSU/DSU expense	5.1		5.0		10.7		10.1
Total stock-based compensation expense	$	13.0	$	15.1	$	26.9	$	30.2

The Company grants PRSUs to executive officers and certain members of management. Actual payout under the PRSUs is dependent upon the achievement of certain financial goals. During the first quarter of 2022, the Company granted PRSUs as a component of the long-term incentive plan ("2022 PRSUs"). The Company has recorded stock-based compensation expense related to the 2022 PRSUs during the three and six months ended June 30, 2022, as it was probable that the Company would achieve the specified performance target for the performance period.