Marketable Securities (Maturities of Marketable Securities) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 29, 2014	Dec. 28, 2013
Marketable Securities [Abstract]
Amortized Cost, Due within one year	$ 5,133
Fair Value, Due within one year	5,160
Amortized Cost, Due after one year through five years	37,973
Fair Value, Due after one year through five years	39,235
Amortized Cost, Due after five years through ten years	12,467
Fair Value, Due after five years through ten years	12,605
Amortized Cost, Equity securities	1,198
Fair Value, Equity securities	8,013
Available-for-sale Securities, Amortized Cost Basis, Total	56,771	56,401
Available-for-sale Securities, Fair Value, Total	$ 65,013	$ 63,093