CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Pension and other postretirement plans adjustments:
Net Prior Service Cost, Tax		$ 0.0	$ 0.3	$ 0.0
Tax benefit (expense) on net unamortized gain (loss) incurred	[1]	3.3	0.3	8.5
Tax expense on prior service cost incurred		(0.5)	(4.9)	(6.0)
Amortization of Net Actuarial Gain (Loss), Tax	[2]	(0.3)	(0.2)	(0.3)
Net Curtailment And Settlements, Tax		$ 0.0	$ (2.6)	$ (3.5)

[1] Presented net of income tax benefit of $3.3 million, $0.3 million and $8.5 million for the years ended December 31, 2016, 2015 and 2014, respectively

[2] Presented net of income tax expense of $0.5 million, $4.9 million, and $6.0 million during the years ended December 31, 2016, 2015, and 2014, respectively.