Retirement Benefit Plans Deferred Compensation (Details) - USD ($)	12 Months Ended
Dec. 31, 2016	Dec. 26, 2015	Dec. 27, 2014
Schedule of Deferred Compensation
Company's maximum match under employee deferred compensation program	$ 4,500
Deferred compensation arrangement with individual, employer contribution	$ 600,000	$ 500,000	$ 500,000

The amount of payment into the fund established for purposes of making future disbursements to the individual in accordance with the terms and understanding of the deferred compensation arrangement.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration