Goodwill and Other Intangible Assets - Goodwill (Details) - USD ($)	3 Months Ended	6 Months Ended
	Jun. 27, 2020	Jun. 27, 2020
Goodwill [Roll Forward]
Goodwill, gross, beginning balance		$ 315,339,000
Accumulated impairment losses, beginning balance		(44,519,000)
Goodwill, net, beginning balance		270,820,000
Goodwill acquired		10,537,000
Impairment losses	$ 0	(21,607,000)
Foreign currency translation adjustment		27,000
Goodwill, gross, ending balance	325,903,000	325,903,000
Accumulated impairment losses, ending balance	(66,126,000)	(66,126,000)
Goodwill, net, ending balance	259,777,000	259,777,000
Workplace furnishings
Goodwill [Roll Forward]
Goodwill, gross, beginning balance		128,677,000
Accumulated impairment losses, beginning balance		(44,376,000)
Goodwill, net, beginning balance		84,301,000
Goodwill acquired		0
Impairment losses		(21,607,000)
Foreign currency translation adjustment		27,000
Goodwill, gross, ending balance	128,704,000	128,704,000
Accumulated impairment losses, ending balance	(65,983,000)	(65,983,000)
Goodwill, net, ending balance	62,721,000	62,721,000
Residential building products
Goodwill [Roll Forward]
Goodwill, gross, beginning balance		186,662,000
Accumulated impairment losses, beginning balance		(143,000)
Goodwill, net, beginning balance		186,519,000
Goodwill acquired		10,537,000
Impairment losses		0
Foreign currency translation adjustment		0
Goodwill, gross, ending balance	197,199,000	197,199,000
Accumulated impairment losses, ending balance	(143,000)	(143,000)
Goodwill, net, ending balance	$ 197,056,000	$ 197,056,000