CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018
Income Statement [Abstract]
Net sales	$ 625,386	$ 611,120	$ 1,630,868	$ 1,659,803
Cost of sales	387,715	377,789	1,030,993	1,048,683
Gross profit	237,671	233,331	599,875	611,120
Selling and administrative expenses	176,731	179,577	511,080	524,445
Restructuring and impairment charges	284	128	1,214	2,303
Operating income	60,656	53,626	87,581	84,372
Interest expense, net	2,205	2,522	6,795	7,375
Income before income taxes	58,451	51,104	80,786	76,997
Income taxes	12,375	11,197	17,878	16,033
Net income	46,076	39,907	62,908	60,964
Less: Net loss attributable to non-controlling interest	(2)	0	(2)	(50)
Net income attributable to HNI Corporation	$ 46,078	$ 39,907	$ 62,910	$ 61,014
Average number of common shares outstanding – basic (in shares)	42,899	43,823	43,217	43,616
Net income attributable to HNI Corporation per common share – basic (in dollars per share)	$ 1.07	$ 0.91	$ 1.46	$ 1.40
Average number of common shares outstanding – diluted (in shares)	43,186	44,679	43,620	44,349
Net income attributable to HNI Corporation per common share – diluted (in dollars per share)	$ 1.07	$ 0.89	$ 1.44	$ 1.38
Foreign currency translation adjustments	$ (1,035)	$ (817)	$ (406)	$ (1,944)
Change in unrealized gains (losses) on marketable securities, net of tax	36	(6)	252	(99)
Change in pension and post-retirement liability, net of tax	0	0	(1,185)	0
Change in derivative financial instruments, net of tax	(477)		(2,112)
Change in derivative financial instruments, net of tax		106		1,459
Other comprehensive loss, net of tax	(1,476)	(717)	(3,451)	(584)
Comprehensive income	44,600	39,190	59,457	60,380
Less: Comprehensive loss attributable to non-controlling interest	(2)	0	(2)	(50)
Comprehensive income attributable to HNI Corporation	$ 44,602	$ 39,190	$ 59,459	$ 60,430