Postretirement and Other Benefits (Tables)

3 Months Ended

Mar. 31, 2022

Retirement Benefits [Abstract]

Schedule of Net Benefit Costs

The components of net pension benefit costs for U.S., French and UK employees during the three months ended March 31, 2022 and 2021 were as follows ($ in millions):

	Three Months Ended March 31,
	U.S. Pension Benefits				French Pension Benefits				UK Pension Benefits
	2022		2021		2022		2021		2022		2021
Service cost	$	—	$	—	$	0.4	$	0.3	$	—	$	—
Interest cost	0.8		0.7		0.1		—		0.5		—
Expected return on plan assets	(1.0)		(1.0)		—		—		(0.6)		—
Amortizations and other	0.4		0.9		0.1		0.3		—		—
Net periodic benefit cost	$	0.2	$	0.6	$	0.6	$	0.6	$	(0.1)	$	—