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Significant Accounting and Reporting Policies - Schedule of Goodwill and Other Indefinite-lived Intangible Assets (Details) - USD ($) $ in Millions	12 Months Ended
	May 28, 2022	May 29, 2021	May 30, 2020	Jul. 19, 2021
Goodwill [Roll Forward]
Goodwill	$ 489.7	$ 471.5	$ 303.8
Sale of owned dealer	(0.3)
Foreign currency translation adjustments	(41.2)	18.2	(0.9)
Impairment loss	(125.5)	(125.5)	(125.5)
Net goodwill	1,226.2	364.2	346.0
Indefinite-lived Intangible Assets [Roll Forward]
Beginning balance	97.6	92.8
Foreign currency translation adjustments	(14.6)	4.8
Ending balance	501.0	97.6	92.8
America's Contract
Goodwill [Roll Forward]
Goodwill	233.9	228.2	193.2
Sale of owned dealer	(0.3)
Foreign currency translation adjustments	(5.2)	5.7	0.0
Impairment loss	(36.7)	(36.7)	(36.7)
Net goodwill	191.7	197.2	191.5
International Contract
Goodwill [Roll Forward]
Goodwill	91.3	84.5	31.6
Sale of owned dealer	0.0
Foreign currency translation adjustments	(8.8)	6.8	(0.7)
Impairment loss	0.0	0.0	0.0
Net goodwill	82.5	91.3	84.5
Global Retail
Goodwill [Roll Forward]
Goodwill	164.5	158.8	79.0
Sale of owned dealer	0.0
Foreign currency translation adjustments	(7.3)	5.7	(0.2)
Impairment loss	(88.8)	(88.8)	(88.8)
Net goodwill	68.4	75.7	70.0
Knoll
Goodwill [Roll Forward]
Goodwill	0.0	0.0	0.0
Goodwill acquired	903.5
Sale of owned dealer	0.0
Foreign currency translation adjustments	(19.9)	0.0	0.0
Impairment loss	0.0	0.0	0.0
Net goodwill	883.6	$ 0.0	0.0
Knoll
Goodwill [Roll Forward]
Goodwill acquired	903.5
Net goodwill				$ 903.5
Knoll \| America's Contract
Goodwill [Roll Forward]
Goodwill acquired	0.0
Knoll \| International Contract
Goodwill [Roll Forward]
Goodwill acquired	0.0
Knoll \| Global Retail
Goodwill [Roll Forward]
Goodwill acquired	$ 0.0
Knoll \| Knoll
Goodwill [Roll Forward]
Net goodwill				$ 903.5
HAY
Goodwill [Roll Forward]
Goodwill acquired			168.6
HAY \| America's Contract
Goodwill [Roll Forward]
Goodwill acquired			35.0
HAY \| International Contract
Goodwill [Roll Forward]
Goodwill acquired			53.6
HAY \| Global Retail
Goodwill [Roll Forward]
Goodwill acquired			80.0
HAY \| Knoll
Goodwill [Roll Forward]
Goodwill acquired			$ 0.0