Goodwill and Other Intangible Assets - Goodwill Rollforward (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014
Acquired Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 24.1	$ 24.1	$ 24.1	$ 24.1	$ 24.1	$ 24.1	$ 24.1	$ 23.8
Intangible Assets, Net (Excluding Goodwill)	29.2	36.4	29.2	36.4	32.2	31.3	39.0	38.7
Disposal Group, Including Discontinued Operation, Intangible Assets		(0.6)		(0.6)	$ 0.3	$ 0.4	$ 0.7	$ 0.8
Goodwill, Acquired During Period				0.3
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill			0.0	2.8
Finite-lived Intangible Assets Acquired			3.9
Amortization of Intangible Assets	$ (3.3)	$ (2.7)	$ (6.4)	$ (5.3)