Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 03, 2015	Sep. 27, 2014	Oct. 03, 2015	Sep. 27, 2014
Accumulated other comprehensive income (loss) [Roll Forward]
Balance at January 1, 2015			$ (11,523)	$ (4,393)
Unrealized losses	$ (1,561)	$ (1,263)	(3,828)	(1,266)
Amounts reclassified from accumulated other comprehensive income (loss)			1,083	541
Tax effect			(412)	(205)
Net of tax amount			(3,157)	(930)
Balance at October 3, 2015	(14,680)	(5,323)	(14,680)	(5,323)
Foreign currencty translation adjustments [Member]
Accumulated other comprehensive income (loss) [Roll Forward]
Balance at January 1, 2015			(1,151)	1,647
Unrealized losses			(3,828)	(1,266)
Amounts reclassified from accumulated other comprehensive income (loss)			0	0
Tax effect			0	0
Net of tax amount			(3,828)	(1,266)
Balance at October 3, 2015	(4,979)	381	(4,979)	381
Defined benefit pension plans [member]
Accumulated other comprehensive income (loss) [Roll Forward]
Balance at January 1, 2015			(10,372)	(6,040)
Unrealized losses			0	0
Amounts reclassified from accumulated other comprehensive income (loss)			1,083	541
Tax effect			(412)	(205)
Net of tax amount			671	336
Balance at October 3, 2015	$ (9,701)	$ (5,704)	$ (9,701)	$ (5,704)