Accumulated Other Comprehensive Income (Loss) and Shareholders' Equity (Reclassification) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest (expense) or income	$ (2,602)	$ (1,835)	$ (7,657)	$ (4,228)
Tax (expense) or benefit	(11,197)	(18,624)	(16,033)	(27,573)
Net income attributable to HNI Corporation	39,907	37,271	61,014	55,956
Interest rate swap \| Reclassifications from accumulated other comprehensive income (loss) \| Derivative Financial Instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest (expense) or income	305	(27)	661	(328)
Tax (expense) or benefit	(75)	10	(162)	121
Net income attributable to HNI Corporation	$ 230	$ (17)	$ 499	$ (207)

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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