Accumulated Other Comprehensive Income (Loss) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 28, 2014	Jun. 29, 2013	Jun. 28, 2014	Jun. 29, 2013
Accumulated Other Comprehensive Income
Beginning Balance			$ 61,634
Other comprehensive income before reclassifications			(6,611)
Tax effect			(640)
Other comprehensive income before reclassifications, net of tax			(7,251)
Amounts reclassified out of AOCI			4,492
Tax effect			(1,632)
Amounts reclassified out of AOCI, net of tax			2,860
Net other comprehensive income	(5,462)	12,747	(4,391)	(8,713)
Ending Balance	57,243		57,243
Unrealized Gain (Loss) on Available-for-Sale Securities [Member]
Accumulated Other Comprehensive Income
Beginning Balance			554
Other comprehensive income before reclassifications			1,828
Tax effect			(640)
Other comprehensive income before reclassifications, net of tax			1,188
Amounts reclassified out of AOCI			0
Tax effect			0
Amounts reclassified out of AOCI, net of tax			0
Net other comprehensive income			1,188
Ending Balance	1,742		1,742
Currency Translation Adjustment [Member]
Accumulated Other Comprehensive Income
Beginning Balance			190,998
Other comprehensive income before reclassifications			(8,439)
Tax effect			0
Other comprehensive income before reclassifications, net of tax			(8,439)
Amounts reclassified out of AOCI			0
Tax effect			0
Amounts reclassified out of AOCI, net of tax			0
Net other comprehensive income			(8,439)
Ending Balance	182,559		182,559
Pension and Other Post-Retirement Actuarial Items [Member]
Accumulated Other Comprehensive Income
Beginning Balance			(129,918)
Other comprehensive income before reclassifications			0
Tax effect			0
Other comprehensive income before reclassifications, net of tax			0
Amounts reclassified out of AOCI			4,492
Tax effect			(1,632)
Amounts reclassified out of AOCI, net of tax			2,860
Net other comprehensive income			2,860
Ending Balance	$ (127,058)		$ (127,058)