Benefit Plans

3 Months Ended

Mar. 31, 2020

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

Benefit Plans

Benefit Plans

The components of net periodic benefit cost for the three months ended March 31 were as follows:

	Pension benefits				Other retirement benefits				Total
($ in millions)	2020		2019		2020		2019		2020		2019
Service cost	$	0.3	$	0.4	$	—	$	—	$	0.3	$	0.4
Interest cost	1.9		2.4		0.1		0.1		2.0		2.5
Expected return on assets	(3.0)		(2.9)		—		—		(3.0)		(2.9)
Amortization of prior service credit	—		—		(0.2)		(0.2)		(0.2)		(0.2)
Recognized actuarial losses (gains)	0.5		0.5		(0.4)		(0.5)		0.1		—
Settlements	1.4		—		—		—		1.4		—
Net periodic benefit cost	$	1.1	$	0.4	$	(0.5)	$	(0.6)	$	0.6	$	(0.2)

	Pension benefits				Other retirement benefits				Total
($ in millions)	2020		2019		2020		2019		2020		2019
U.S. plans	$	0.8	$	(0.1)	$	(0.5)	$	(0.6)	$	0.3	$	(0.7)
International plans	0.3		0.5		—		—		0.3		0.5
Net periodic benefit cost	$	1.1	$	0.4	$	(0.5)	$	(0.6)	$	0.6	$	(0.2)

During the three months ended March 31, 2020, we recorded a $1.4 million pension settlement charge within other nonoperating expense (income), as we determined that normal-course lump-sum payments for our U.S. qualified defined benefit pension plan exceeded the threshold for settlement accounting under U.S. GAAP for the year.