Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 24, 2018	Dec. 30, 2017	Mar. 25, 2017	Dec. 31, 2016
Financial assets, Carrying Amount
Cash and cash equivalents, Carrying Amount	$ 2,863	$ 1,572	$ 2,536	$ 1,013
Financial liabilities, Carrying Amount
Current portion of Long-term debt, Carrying Amount	18,941	1,250	1,300
Long-term debt, Carrying Amount	3,750	21,871	23,000
Fair Value, Inputs, Level 1 [Member]
Financial assets, Fair Value
Cash and cash equivalents, Fair Value	2,863	1,572	2,536
Financial liabilities, Fair Value
Current portion of Long-term debt, Fair Value	0	0	0
Long-term debt, Fair Value	0	0	0
Fair Value, Inputs, Level 2 [Member]
Financial assets, Fair Value
Cash and cash equivalents, Fair Value	0	0	0
Financial liabilities, Fair Value
Current portion of Long-term debt, Fair Value	18,941	1,250	1,300
Long-term debt, Fair Value	3,750	21,871	23,000
Fair Value, Inputs, Level 3 [Member]
Financial assets, Fair Value
Cash and cash equivalents, Fair Value	0	0	0
Financial liabilities, Fair Value
Current portion of Long-term debt, Fair Value	0	0	0
Long-term debt, Fair Value	$ 0	$ 0	$ 0

No definition available.

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- Definition

For the entity and the disposal group, cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents.

+ References

No definition available.

+ Details

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

No definition available.

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- References

No definition available.

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- References

No definition available.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19,20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount of short-term debt existing as of the balance sheet date.

+ References

No definition available.

+ Details

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