Receivables (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 27, 2018	Dec. 27, 2017
Receivables [Abstract]
Trade accounts receivable from franchisees, gross, current	$ 10,060	$ 10,688
Financing receivables from franchisees, gross, current	4,046	5,084
Allowance for doubtful accounts	(427)	(276)
Total current receivables, net	18,975	21,384
Noncurrent assets (included as a component of other noncurrent assets):
Financing receivables from franchisees, noncurrent	1,329	427
Write-off of financing receivables from a franchisee	200
Vendor receivables [Member]
Receivables [Abstract]
Other receivables, gross, current	2,003	3,256
Credit card receivables [Member]
Receivables [Abstract]
Other receivables, gross, current	1,458	1,870
Other [Member]
Receivables [Abstract]
Other receivables, gross, current	$ 1,835	$ 762

Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business.

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- Definition

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

+ References

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An amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date(s) within one year of the balance sheet date or the normal operating cycle, whichever is longer. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

+ References

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An amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date more than one year from the balance sheet date, net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

+ References

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- Definition

Amount, before allowance, of receivables classified as other, due within one year or the operating cycle, if longer.

+ References

No definition available.

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- Definition

Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

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- Definition

The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value.

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- References

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