Retirement Benefits (Tables)

3 Months Ended

Mar. 31, 2017

Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]

Components of Net Periodic (Benefit Credit) Benefit Cost

The components of net periodic benefit credit included in the consolidated statements of income for the three months ended March 31, 2017 and 2016 are as follows:

	Pension Benefits						Other Benefits
	Three Months Ended   March 31						Three Months Ended   March 31
	2017			2016			2017			2016
Service cost	$	2.5		$	2.8		$	0.3		$	0.4
Interest cost	16.6			17.3			5.2			5.6
Expected return on assets	(36.8		)	(36.7		)	(5.7		)	(5.6		)
Recognized actuarial loss	5.4			4.4			2.9			3.1
Settlement loss	1.7			2.4			—			—
Amortization of prior service credit	(0.1		)	(0.1		)	(3.4		)	(3.5		)
Net periodic benefit credit	$	(10.7	)	$	(9.9	)	$	(0.7	)	$	—