Other Intangible Assets - Schedule of Finite-lived Intangible Assets (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Jun. 30, 2017
Finite-Lived Intangible Assets [Line Items]
Gross	$ 215.3	$ 202.4
Accumulated Amortization	(111.1)	(101.0)
Net	104.2	101.4	$ 2.4
Franchising rights
Finite-Lived Intangible Assets [Line Items]
Gross	200.0	200.0
Accumulated Amortization	(111.0)	(101.0)
Net	89.0	99.0
Reacquired Franchise Rights
Finite-Lived Intangible Assets [Line Items]
Gross	11.6	0.0
Accumulated Amortization	(0.1)	0.0
Net	11.5	0.0
Leaseholds
Finite-Lived Intangible Assets [Line Items]
Gross	3.7	2.4
Accumulated Amortization	0.0	$ 0.0
Net	$ 3.7