Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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Franchise Operating Rights & Goodwill - Impairment (Details) $ in Millions		12 Months Ended
	Oct. 01, 2019 USD ($) item	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Franchise operating rights
Number of reporting units which franchise operating rights were impaired \| item	2
Impairment of franchise operating rights		$ 9.7	$ 143.2	$ 14.1
Goodwill
Impairment of goodwill			73.1	$ 133.3
Accumulated impairment		$ 206.4	$ 206.4
Newnan, GA
Franchise operating rights
Impairment of franchise operating rights	$ 4.2
Dothan, AL
Franchise operating rights
Impairment of franchise operating rights	$ 5.5