Financing Receivables - Schedule of Amortized Cost by Origination Year (Details) - USD ($) $ in Millions	Sep. 25, 2020	Dec. 31, 2019
PSAs
Financing Receivable, Credit Quality Indicator [Line Items]
2020	$ 136.5
2019	99.0
2018	51.5
2017	22.6
2016	7.3
Prior	2.1
Total	319.0	$ 327.5
PSAs | Less than 400
Financing Receivable, Credit Quality Indicator [Line Items]
2020	14.1
2019	12.0
2018	5.6
2017	2.6
2016	0.8
Prior	0.4
Total	35.5
PSAs | 400-599
Financing Receivable, Credit Quality Indicator [Line Items]
2020	20.6
2019	15.9
2018	8.6
2017	3.8
2016	1.3
Prior	0.6
Total	50.8
PSAs | 600-799
Financing Receivable, Credit Quality Indicator [Line Items]
2020	42.2
2019	30.5
2018	16.1
2017	7.6
2016	2.8
Prior	0.7
Total	99.9
PSAs | 800+
Financing Receivable, Credit Quality Indicator [Line Items]
2020	59.6
2019	40.6
2018	21.2
2017	8.6
2016	2.4
Prior	0.4
Total	132.8
Franchisee Notes
Financing Receivable, Credit Quality Indicator [Line Items]
2020	16.0
2019	23.5
2018	11.6
2017	8.0
2016	5.4
Prior	8.5
Total	73.0
Franchisee Notes | Active distributors
Financing Receivable, Credit Quality Indicator [Line Items]
2020	15.9
2019	22.4
2018	10.0
2017	6.5
2016	3.4
Prior	4.5
Total	62.7
Franchisee Notes | Separated distributors
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0.1
2019	1.1
2018	1.6
2017	1.5
2016	2.0
Prior	4.0
Total	$ 10.3