Goodwill And Intangible Assets, Net (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	$ 1,513.6	$ 1,515.0
Franchise rights - indefinite-lived	572.2	572.2
Other intangibles	24.1	23.3
Other intangible assets, gross	596.3	595.5
Less: accumulated amortization	(9.0)	(8.7)
Other intangible assets, net	$ 587.3	$ 586.8