Investments (Details) (USD $) In Thousands, unless otherwise specified	Mar. 29, 2014	Dec. 28, 2013
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 4,428	$ 8,642
Estimated Fair Value	4,428	8,642
Certificates of Deposit [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	4,428	8,642
Estimated Fair Value	$ 4,428	$ 8,642