Supplemental Balance Sheet Other Assets, Current (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 27, 2014	Dec. 28, 2013	Dec. 29, 2012
Other Assets, Current [Line Items]
Provision for Doubtful Accounts	$ 512us-gaap_ProvisionForDoubtfulAccounts	$ 1,332us-gaap_ProvisionForDoubtfulAccounts	$ 947us-gaap_ProvisionForDoubtfulAccounts
Other current assets	99,841	86,597
Prepaid assets	26,900us-gaap_PrepaidExpenseCurrent	20,058us-gaap_PrepaidExpenseCurrent
Deferred tax asset	27,644us-gaap_DeferredTaxAssetsNetCurrent	29,889us-gaap_DeferredTaxAssetsNetCurrent
Prepaid income tax	26,287us-gaap_PrepaidTaxes	25,247us-gaap_PrepaidTaxes
Restricted cash	2,552	245
Bank Time Deposits [Member]
Other Assets, Current [Line Items]
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	$ 16,167	$ 11,158

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