CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Pension and other postretirement plans adjustments:
Amortization of net actuarial loss, income tax expense	$ (0.1)	$ 0.0	$ (0.3)	$ (0.2)
Amortization of prior service cost, income tax expense	$ (0.1)	$ (0.1)	$ (0.3)	$ (0.5)