Retirement Benefit Plans (Tables)

3 Months Ended

Mar. 31, 2017

Compensation and Retirement Disclosure [Abstract]

Components of Net Pension Expense

The components of net periodic pension expense for our U.S. and foreign defined benefit pension plans are as follows (in millions):

	Three Months Ended March 31,
	2017			2016
Service cost	$	7.5		$	7.5
Interest cost		4.7			7.2
Expected return on plan assets		(10.1	)		(12.7	)
Curtailment gain		—			(0.3	)
Amortization of prior service cost		(2.6	)		(1.9	)
Amortization of unrecognized actuarial loss		5.6			5.0
Net periodic pension expense	$	5.1		$	4.8