Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2023

Share-Based Payment Arrangement [Abstract]

Schedule of Compensation Expense

Stock-based compensation cost by award type follows:

(in millions)	Three Months Ended June 30,				Six Months Ended June 30,
	2023		2022		2023		2022
Stock option awards	$	5.0	$	2.2	$	10.1	$	5.1
Restricted stock awards	2.2		1.7		5.4		4.9
Performance share awards	3.6		2.1		6.0		5.1
Total stock-based compensation cost incurred	10.8		6.0		21.5		15.1
Capitalized cost during the period	(1.6)		—		(3.2)		—
Amortization of capitalized cost during the period	1.6		—		3.5		—
Total stock-based compensation expense	$	10.8	$	6.0	$	21.8	$	15.1