Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 04, 2015	Jun. 28, 2014	Jul. 04, 2015	Jun. 28, 2014
Accumulated other comprehensive income (loss) [Roll Forward]
Balance at January 1, 2015			$ (11,523)
Unrealized losses	$ (84)	$ 971	(2,267)	$ (3)
Amounts reclassified from accumulated other comprehensive income (loss)			737
Tax effect			(280)
Net of tax amount			(1,810)
Balance at July 4, 2015	(13,333)		(13,333)
Foreign currencty translation adjustments [Member]
Accumulated other comprehensive income (loss) [Roll Forward]
Balance at January 1, 2015			(1,151)
Unrealized losses			(2,267)
Amounts reclassified from accumulated other comprehensive income (loss)			0
Tax effect			0
Net of tax amount			(2,267)
Balance at July 4, 2015	(3,418)		(3,418)
Accumulated defined benefit plans adjustment [member]
Accumulated other comprehensive income (loss) [Roll Forward]
Balance at January 1, 2015			(10,372)
Unrealized losses			0
Amounts reclassified from accumulated other comprehensive income (loss)			737
Tax effect			(280)
Net of tax amount			457
Balance at July 4, 2015	$ (9,915)		$ (9,915)