Restructuring Costs Expensed (Details) - Realignment of Office Furniture Facilities and Exit of Business Line - USD ($) $ in Thousands	3 Months Ended
	Mar. 30, 2019	Mar. 31, 2018
Restructuring Cost and Reserve [Line Items]
Restructuring costs		$ 1,338
Restructuring and impairment charges
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 0	$ 1,338