CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (55.6)		$ 39.7
Pension and other postretirement plans adjustments:
Amortization of net actuarial loss	0.2	[1]	0.1	[1]
Amortization of prior service cost	0.5	[2]	0.9	[2]
Total pension and other postretirement plans adjustments	0.7		1.0
Other comprehensive income	0.7		1.0
Comprehensive income (loss)	$ (54.9)		$ 40.7

[1] Presented net of income tax expense of $0.1 million and $0.1 million during the three months ended March 31, 2015, and 2014, respectively.

[2] Presented net of income tax expense of $0.3 million and $0.4 million during the three months ended March 31, 2015, and 2014, respectively.