Employee benefit plans (Tables)

6 Months Ended

Jun. 30, 2020

Postemployment Benefits [Abstract]

Components of Net Periodic Benefit Cost (Credit)

The following table summarizes the components of net periodic (benefit) cost recognized in the condensed consolidated statements of operations:

	Domestic - Defined Benefit Pension Plans								Foreign - Defined Benefit Pension Plans
	Three months ended June 30,				Six months ended June 30,				Three months ended June 30,				Six months ended June 30,
(in millions)	2020		2019		2020		2019		2020		2019		2020		2019
Service cost (1)	$	—	$	—	$	—	$	—	$	0.4	$	0.6	$	0.9	$	1.2
Interest cost (2)	5.8		6.8		11.6		13.6		3.0		3.9		6.1		7.8
Expected return on plan assets (2)	(7.2)		(6.3)		(14.3)		(12.6)		(3.8)		(5.1)		(7.8)		(10.1)
Prior service cost (2)	—		—		—		—		0.1		0.1		0.1		0.1
Net periodic (benefit) cost	$	(1.4)	$	0.5	$	(2.7)	$	1.0	$	(0.3)	$	(0.5)	$	(0.7)	$	(1.0)

(1)Service cost is included in warehouse, selling and administrative expenses.

(2)These amounts are included in other expense, net.