Reportable Segment Information (Business Segment Information) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) Segment	Jan. 02, 2016 USD ($)	Jan. 03, 2015 USD ($)
Segment Reporting [Abstract]
Number of business segments | Segment	2
Segment Reporting Information [Line Items]
Net sales	$ 2,203,489	$ 2,304,419	$ 2,222,695
Income (loss) before income taxes	128,911	157,170	104,931
Depreciation and amortization expense	68,947	57,564	56,722
Capital expenditures (including capitalized software)	119,584	114,966	112,713
Identifiable assets	1,330,234	1,263,925	1,239,334
Restructuring and impairment charges	11,005	11,792	33,019
Office Furniture
Segment Reporting Information [Line Items]
Restructuring and impairment charges	10,900	11,600	38,200
Hearth Products
Segment Reporting Information [Line Items]
Restructuring and impairment charges	5,500	900
Operating
Segment Reporting Information [Line Items]
Operating profit	187,357	214,755	164,119
Operating | Office Furniture
Segment Reporting Information [Line Items]
Net sales	1,703,885	1,777,804	1,739,049
Operating profit	117,397	136,593	87,053
Depreciation and amortization expense	45,088	42,415	45,891
Capital expenditures (including capitalized software)	65,944	64,850	62,696
Identifiable assets	749,145	739,915	724,293
Operating | Hearth Products
Segment Reporting Information [Line Items]
Net sales	499,604	526,615	483,646
Operating profit	69,960	78,162	77,066
Depreciation and amortization expense	12,486	8,430	5,415
Capital expenditures (including capitalized software)	11,217	11,078	6,342
Identifiable assets	340,494	341,813	341,315
General corporate
Segment Reporting Information [Line Items]
Unallocated corporate expenses	(58,446)	(57,585)	(59,188)
Depreciation and amortization expense	11,373	6,719	5,416
Capital expenditures (including capitalized software)	42,423	39,038	43,675
Identifiable assets	$ 240,595	$ 182,197	$ 173,726