Basis and Summary of Significant Accounting Policies - Accounts Receivable Net of Allowances (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts Receivable	$ 84,309	$ 99,887
Customers
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts Receivable	48,978	48,661
Corporate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts Receivable	12,860	23,431
Franchisee
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts Receivable	$ 22,471	$ 27,795