Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2020

Share-based Payment Arrangement [Abstract]

Summary of Stock-Based Compensation Expense by Type of Award

The following table summarizes stock-based compensation expense by type of award:

	Three months ended September 30,				Nine months ended September 30,
	2020		2019		2020		2019
	(In millions)
Stock Appreciation Rights	$	0.6	$	5.1	$	(1.3)	$	12.7
Stock options	0.1		0.1		0.3		0.2
Restricted stock and restricted stock units, service based	1.5		1.3		4.7		4.0
Restricted stock and restricted stock units, performance based	3.0		2.2		8.7		6.9
Employee stock purchase plan	0.3		0.3		0.8		0.7
Total stock-based compensation expense	$	5.5	$	9.0	$	13.2	$	24.5