Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 30, 2019	Mar. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ (5,034)	$ (8,393)
Unrealized gains (losses)	509	(832)
Amounts reclassified from accumulated other comprehensive income (loss)	60	198
Tax effect	(16)	(52)
Net of tax amount	553	(686)
Ending balance	(4,481)	(9,079)
Foreign currency translation adjustments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(5,819)	(3,305)
Unrealized gains (losses)	509	(832)
Amounts reclassified from accumulated other comprehensive income (loss)	0	0
Tax effect	0	0
Net of tax amount	509	(832)
Ending balance	(5,310)	(4,137)
Defined benefit pension plans [member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	785	(5,088)
Unrealized gains (losses)	0	0
Amounts reclassified from accumulated other comprehensive income (loss)	60	198
Tax effect	(16)	(52)
Net of tax amount	44	146
Ending balance	$ 829	$ (4,942)