Debt (Financing Liability) (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
	Mar. 29, 2015	Mar. 29, 2015	Mar. 30, 2014	Dec. 28, 2014
Debt Instrument [Line Items]
Financing liability	$ 31,187	$ 31,187		$ 33,094
SPAIN
Debt Instrument [Line Items]
Other operating income from sale of rights to future customer receivables	400
Financing Agreement June 2011 | SPAIN
Debt Instrument [Line Items]
Financing liability	$ 30,100	$ 30,100		$ 33,100
Financing arrangement, imputed interest on financing liability	6.365%	6.365%
Financing arrangement, interest expense recognized		$ 500	$ 600
Financing Agreement 2015 [Member] | SPAIN
Debt Instrument [Line Items]
Financing liability	$ 1,100	$ 1,100