Accumulated Other Comprehensive Income (Loss) (Details) $ in Thousands	9 Months Ended
	Sep. 29, 2017 USD ($)
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	$ 258,870
Other comprehensive income (loss)	7,509
Amounts reclassified from other comprehensive income (loss)	874	[1]
Ending Balance	309,147
Total accumulated other Foreign currency comprehensive translation Pension income (loss)
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(27,715)
Ending Balance	(19,332)
Foreign currency translation adjustments
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(17,222)
Other comprehensive income (loss)	8,340
Ending Balance	(8,882)
Pension liabilities
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(10,493)
Other comprehensive income (loss)	(831)
Amounts reclassified from other comprehensive income (loss)	874	[1]
Ending Balance	$ (10,450)

[1] The amounts reclassified from other comprehensive income (loss) were included in selling, general and administrative expenses in the consolidated statements of operations.