Consolidated Statement of Comprehensive Income - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	[1]	Sep. 30, 2016	Sep. 30, 2015	[1]
Statement of Comprehensive Income [Abstract]
Net Income	$ 83.1	$ 50.9		$ 221.0	$ 128.7
Defined benefit plans
Plan sponsored by equity affiliate, net of tax	(0.4)			0.3
Other Comprehensive Income	(0.4)			0.3
Comprehensive Income	$ 82.7	$ 50.9		$ 221.3	$ 128.7

[1] Prior-period financial information has been retrospectively adjusted for acquisitions of businesses under common control.