Financing Receivables - Schedule Of Allowance For Credit Losses (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of year	$ 41.3	$ 43.8
Provision for doubtful accounts	35.2	30.9
Write-offs	(39.0)	(35.4)
Recoveries of amounts previously charged off	2.9	2.0
Other adjustment	7.9	0.0
Balances at end of period	66.8	41.3
Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of year	18.5	0.0
Balances at end of period		18.5
PSAs
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of year	29.4	29.6
Provision for doubtful accounts	29.3	26.4
Write-offs	(32.5)	(28.2)
Recoveries of amounts previously charged off	2.7	1.6
Other adjustment	7.9	0.0
Balances at end of period	54.3	29.4
PSAs | Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of year	17.5	0.0
Balances at end of period		17.5
Franchisee Notes
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of year	11.9	14.2
Provision for doubtful accounts	5.9	4.5
Write-offs	(6.5)	(7.2)
Recoveries of amounts previously charged off	0.2	0.4
Other adjustment	0.0	0.0
Balances at end of period	12.5	11.9
Franchisee Notes | Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of year	$ 1.0	0.0
Balances at end of period		$ 1.0