Independent Operator Notes and Receivables - Allowance for Credit Loss (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 28, 2020	Mar. 30, 2019
Accounts And Financing Receivable, Allowance For Credit Loss [Roll Forward]
Beginning balance	$ 10,371	$ 9,067
Provision for independent operator notes and receivables	848	1,483
Cumulative effect of accounting change	439	0
Write-off of provision for independent operator notes and receivables	(188)	(291)
Ending Balance	$ 10,592	$ 10,259