Other Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Mar. 29, 2014	Dec. 31, 2013
Other Liabilities Disclosure [Abstract]
Long-term income taxes payable	$ 2,559	$ 2,574
Deferred compensation	4,342	3,874
Asset retirement obligation	2,279	2,248
Deferred service income-long term	1,025	1,460
Postretirement medical obligation	1,044	1,032
Deferred Tax Liabilities, Gross, Noncurrent	125	125
Other	599	610
Balance, end of the period	$ 11,973	$ 11,923	[1]

[1] The balance sheet as of December 31, 2013 has been derived from the audited financial statements at that date.