Supplemental Financial Information (Accounts Receivable) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Jan. 01, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	$ 3,503	$ 2,391
Tenant improvement receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	0	82
Insurance receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	744	69
Vendor rebate receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	788	639
Franchise and other receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	$ 1,971	$ 1,601