CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Statement of Comprehensive Income [Abstract]
Net income (loss)		$ (197.0)	$ (76.3)	$ (1,060.8)	$ (131.9)
Pension and other postretirement plans adjustments:
Amortization of net actuarial losses	[1]	0.2	0.0	0.3	0.2
Amortization of prior service costs	[2]	0.2	0.1	0.3	0.6
Other comprehensive income		0.4	0.1	0.6	0.8
Comprehensive income (loss)		$ (196.6)	$ (76.2)	$ (1,060.2)	$ (131.1)

[1] Presented net of income tax expense of $0.2 million and $0.3 million during the three and six months ended June 30, 2016, respectively. Presented net of income tax expense of $0.1 million for the six months ended June 30, 2015.

[2] Presented net of income tax of $0.2 million for the three and six months ended June 30, 2016. Presented net of income tax expense of $0.1 million and $0.4 million during the three and six months ended June 30, 2015, respectively.