SEGMENT INFORMATION - Summary of Segment Results from Continuing Operations (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) segment	Jun. 30, 2019 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments \| segment			3
Net trade sales	$ 845.1	$ 1,213.2	$ 1,890.6	$ 2,368.3
Total Sales	852.0	1,228.1	1,913.1	2,398.6
EBIT	22.8	136.0	103.5	234.2
Depreciation and Amortization	46.5	50.0	94.0	96.3
Goodwill impairment	25.4		25.4	0.0
Hydraulic Cylinders group
Segment Reporting Information [Line Items]
Goodwill impairment	25.4		25.4
Bedding Products
Segment Reporting Information [Line Items]
Net trade sales	410.6	568.4	901.2	1,122.7
Total Sales	414.6	578.6	914.8	1,143.1
EBIT	18.6	63.5	48.6	107.6
Depreciation and Amortization	26.3	28.2	53.1	53.0
Goodwill impairment	0.0		0.0
Specialized Products
Segment Reporting Information [Line Items]
Net trade sales	140.8	267.0	375.3	529.9
Total Sales	141.2	267.7	376.5	531.5
EBIT	(19.7)	41.5	8.0	77.2
Depreciation and Amortization	10.6	10.4	21.8	20.6
Goodwill impairment	25.4		25.4
Furniture, Flooring & Textile Products
Segment Reporting Information [Line Items]
Net trade sales	293.7	377.8	614.1	715.7
Total Sales	296.2	381.8	621.8	724.0
EBIT	23.4	31.5	49.9	49.9
Depreciation and Amortization	6.3	6.7	12.8	13.3
Operating segments
Segment Reporting Information [Line Items]
Net trade sales	845.1	1,213.2	1,890.6	2,368.3
Operating segments \| Bedding Products
Segment Reporting Information [Line Items]
Net trade sales	410.6	568.4	901.2	1,122.7
Operating segments \| Specialized Products
Segment Reporting Information [Line Items]
Net trade sales	140.8	267.0	375.3	529.9
Operating segments \| Furniture, Flooring & Textile Products
Segment Reporting Information [Line Items]
Net trade sales	293.7	377.8	614.1	715.7
Intersegment eliminations
Segment Reporting Information [Line Items]
Net trade sales	6.9	14.9	22.5	30.3
EBIT	(0.5)	0.5	3.0	0.5
Depreciation and Amortization	(3.3)	(4.7)	(6.3)	(9.4)
Intersegment eliminations \| Bedding Products
Segment Reporting Information [Line Items]
Net trade sales	4.0	10.2	13.6	20.4
Intersegment eliminations \| Specialized Products
Segment Reporting Information [Line Items]
Net trade sales	0.4	0.7	1.2	1.6
Intersegment eliminations \| Furniture, Flooring & Textile Products
Segment Reporting Information [Line Items]
Net trade sales	$ 2.5	$ 4.0	$ 7.7	$ 8.3

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