Interim Unaudited Statements of Changes in Stockholder's Equity (USD $) In Millions, unless otherwise specified	Total	COMMON STOCK:	ADDITIONAL PAID-IN CAPITAL:	ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS):	RETAINED EARNINGS (ACCUMULATED DEFICIT):
Balance, beginning of period at Dec. 31, 2013	$ 381.4	$ 2.5	$ 847.2	$ (12.7)	$ (455.6)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Capital contributions from parent			0
Other comprehensive income (loss)	(1.4)			(1.4)
Net income (loss)	(15.2)				(15.2)
Change in stockholder’s equity	(16.6)
Balance, end of period at Mar. 31, 2014	364.8	2.5	847.2	(14.1)	(470.8)
Balance, beginning of period at Dec. 31, 2014	303.8	2.5	862.2	4.0	(564.9)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Capital contributions from parent			0
Other comprehensive income (loss)	(1.3)			(1.3)
Net income (loss)	(52.2)				(52.2)
Change in stockholder’s equity	(53.5)
Balance, end of period at Mar. 31, 2015	$ 250.3	$ 2.5	$ 862.2	$ 2.7	$ (617.1)