GOODWILL AND OTHER INTANGIBLE ASSETS, NET - Trade Names Tested For Impairment (Details) $ in Millions	Oct. 01, 2020 USD ($)
Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived intangible asset impairment test, measurement, royalty rate	1.50%
Indefinite- lived intangible asset, impairment test, measurement, discount rate	13.00%
Knoll
Indefinite-lived Intangible Assets [Line Items]
Carrying Amount	$ 187.8
Excess Fair Value	25.00%
Holly Hunt
Indefinite-lived Intangible Assets [Line Items]
Carrying Amount	$ 23.5
Excess Fair Value	1.00%
Muuto
Indefinite-lived Intangible Assets [Line Items]
Carrying Amount	$ 62.1
Muuto \| Minimum
Indefinite-lived Intangible Assets [Line Items]
Excess Fair Value	10000000.00%
Muuto \| Maximum
Indefinite-lived Intangible Assets [Line Items]
Excess Fair Value	20000000.00%

Indefinite- Lived Intangible Asset, Impairment Test, Measurement, Discount Rate

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- Definition

Indefinite- Lived Intangible Asset, Impairment Test, Measurement, Royalty Rate

+ References

No definition available.

+ Details

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- Definition

Indefinite-lived Intangible Assets, Percentage of Fair Value in Excess of Carrying amount

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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