Significant Accounting Policies (Details 4) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 29, 2015	Dec. 28, 2014
Measurement of financial assets and liabilities at fair value on a recurring basis
Transfers among levels within the fair value hierarchy	$ 0
Measured on Recurring Basis \| Level 1
Measurement of financial assets and liabilities at fair value on a recurring basis
Cash surrender value of life insurance policies	18,806	18,238
Measured on Recurring Basis \| Level 2
Measurement of financial assets and liabilities at fair value on a recurring basis
Interest rate swap liabilities	1,470	376
Measured on Recurring Basis \| Carrying Value
Measurement of financial assets and liabilities at fair value on a recurring basis
Cash surrender value of life insurance policies	18,806	18,238
Interest rate swap liabilities	$ 1,470	$ 376

Fair value portion of the amount that could be realized under a life insurance contract or contracts owned by the entity, commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Surrender Value

-URI http://asc.fasb.org/extlink&oid=6507153

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- Definition

Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

+ References

No definition available.

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- Definition

Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13433-108611

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