Benefit Plans (Tables)

6 Months Ended

Jun. 30, 2022

Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]

Schedule of Components of Net Periodic Benefit Cost

The components of net periodic benefit cost for the three months ended June 30 were as follows:

	Pension benefits				Other retirement benefits				Total
($ in millions)	2022		2021		2022		2021		2022		2021
Service cost	$	0.3	$	0.4	$	—	$	—	$	0.3	$	0.4
Interest cost	1.6		1.5		—		—		1.6		1.5
Expected return on assets	(2.4)		(3.0)		—		—		(2.4)		(3.0)
Amortization of prior service credit	—		0.1		—		(0.1)		—		—
Recognized actuarial losses (gains)	0.3		0.5		(0.3)		(0.4)		—		0.1
Settlements	0.6		0.1		—		—		0.6		0.1
Net periodic benefit cost	$	0.4	$	(0.4)	$	(0.3)	$	(0.5)	$	0.1	$	(0.9)

	Pension benefits				Other retirement benefits				Total
($ in millions)	2022		2021		2022		2021		2022		2021
U.S. plans	$	0.3	$	(1.0)	$	(0.3)	$	(0.5)	$	—	$	(1.5)
International plans	0.1		0.6		—		—		0.1		0.6
Net periodic benefit cost	$	0.4	$	(0.4)	$	(0.3)	$	(0.5)	$	0.1	$	(0.9)

The components of net periodic benefit cost for the six months ended June 30 were as follows:

	Pension benefits				Other retirement benefits				Total
($ in millions)	2022		2021		2022		2021		2022		2021
Service cost	$	0.7	$	0.8	$	—	$	—	$	0.7	$	0.8
Interest cost	3.2		2.9		—		0.1		3.2		3.0
Expected return on assets	(4.6)		(6.1)		—		—		(4.6)		(6.1)
Amortization of prior service credit	—		0.1		—		(0.2)		—		(0.1)
Recognized actuarial losses (gains)	0.7		1.0		(0.7)		(0.8)		—		0.2
Settlements	1.2		0.7		—		—		1.2		0.7
Net periodic benefit cost	$	1.2	$	(0.6)	$	(0.7)	$	(0.9)	$	0.5	$	(1.5)

	Pension benefits				Other retirement benefits				Total
($ in millions)	2022		2021		2022		2021		2022		2021
U.S. plans	$	0.7	$	(1.6)	$	(0.7)	$	(0.9)	$	—	$	(2.5)
International plans	0.5		1.0		—		—		0.5		1.0
Net periodic benefit cost	$	1.2	$	(0.6)	$	(0.7)	$	(0.9)	$	0.5	$	(1.5)