Description of Business and Summary of Significant Accounting Policies (Income Taxes) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 27, 2014	Dec. 28, 2013
Accounting Policies [Abstract]
Effect on Unrecognized Tax Benefits of adoption of ASU 2013-11	$ 16,200	$ 11,900

[Table Text Block] for Effect on Unrecognized Tax Benefits of adoption of ASU 2013-11 [Table]

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant