Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Jun. 24, 2012
NET CASH PROVIDED BY OPERATING ACTIVITIES	$ 15,366	$ 34,564
CASH FLOWS FROM INVESTING ACTIVITIES:
Additions to property, plant and equipment	(17,140)	(8,661)
Proceeds from life insurance policy	297	1,726
Proceeds from sales and maturities of investments	2,800	3,142
Purchase of investments	(2,800)	(2,808)
Other	2	240
NET CASH USED IN INVESTING ACTIVITIES	(16,841)	(6,361)
CASH FLOWS FROM FINANCING ACTIVITIES:
Cash dividends paid	0	(8,703)
Proceeds from exercise of stock options	1,133	417
Excess tax benefits from exercise of stock options	324	0
NET CASH PROVIDED BY (USED IN) FINANCING ACTIVITIES	1,457	(8,286)
Effect of exchange rate changes on cash	(810)	(218)
Net (decrease) increase in cash and cash equivalents	(828)	19,699
Cash and cash equivalents at the beginning of the period	203,364	187,795
Cash and cash equivalents at the end of period	$ 202,536	$ 207,494