CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Statement of Comprehensive Income [Abstract]
NET INCOME	$ 10.3	$ 122.8
OTHER COMPREHENSIVE INCOME:
Net reclassification adjustment for amounts recognized in net income as a component of net periodic benefit cost, net of income tax expense of $0.5 and $1.3 for the three months ended March 31, 2017 and 2016, respectively (see Notes 3 and 8).	0.9	2.5
COMPREHENSIVE INCOME	$ 11.2	$ 125.3