Marketable Securities (Maturities of Marketable Securities) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 28, 2014	Dec. 28, 2013
Marketable Securities [Abstract]
Amortized Cost, Due within one year	$ 3,935
Fair Value, Due within one year	3,965
Amortized Cost, Due after one year through five years	39,405
Fair Value, Due after one year through five years	40,822
Amortized Cost, Due after five years through ten years	11,942
Fair Value, Due after five years through ten years	12,194
Amortized Cost, Equity securities	1,198
Fair Value, Equity securities	8,132
Amortized Cost, Total	56,480	56,401
Available-for-sale Securities, Fair Value, Total	$ 65,113	$ 63,093