Retirement Benefit Plans (Tables)

6 Months Ended

Jun. 30, 2016

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 June 30,						Six Months Ended June 30,
	2016			2015			2016			2015
Service cost	$	7.7		$	7.6		$	15.2		$	15.2
Interest cost		7.4			5.6			14.6			11.1
Expected return on plan assets		(12.7	)		(10.9	)		(25.4	)		(21.8	)
Curtailment gain		(0.3	)		—			(0.6	)		—
Amortization of prior service cost		(2.0	)		(1.2	)		(3.9	)		(2.3	)
Amortization of unrecognized actuarial loss		5.0			4.2			10.0			8.5
Net periodic pension expense	$	5.1		$	5.3		$	9.9		$	10.7