SEGMENT INFORMATION - Summary of Segment Results from Continuing Operations (Details) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) segment	Sep. 30, 2020 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments | segment				3
Net trade sales	$ 1,319.2	$ 1,207.6		$ 3,739.7	$ 3,098.2
Total Sales	1,334.8	1,221.2		3,784.8	3,134.3
EBIT	144.2	150.2		443.8	251.5
Depreciation and Amortization	46.6	47.0		140.8	141.0
Goodwill impairment		0.0		0.0	25.4
Fashion Bed Business
Segment Reporting Information [Line Items]
Gain on sale of real estate					28.2
Hydraulic Cylinders Group
Segment Reporting Information [Line Items]
Goodwill impairment			$ 25.4		25.4
Bedding Products
Segment Reporting Information [Line Items]
Total Sales	675.5	599.8		1,841.0	1,514.6
EBIT	81.1	75.8		245.3	123.0
Depreciation and Amortization	27.3	26.6		79.8	79.7
Goodwill impairment		0.0			0.0
Specialized Products
Segment Reporting Information [Line Items]
Net trade sales	235.6	242.9		734.9	618.2
Total Sales	236.6	243.7		737.5	620.2
EBIT	22.4	32.6		85.0	40.6
Depreciation and Amortization	11.7	10.7		35.0	32.5
Goodwill impairment		0.0			25.4
Furniture, Flooring & Textile Products
Segment Reporting Information [Line Items]
Net trade sales	419.5	374.9		1,196.2	989.0
Total Sales	422.7	377.7		1,206.3	999.5
EBIT	41.1	42.5		114.1	91.6
Depreciation and Amortization	6.0	6.3		18.1	19.1
Operating segments
Segment Reporting Information [Line Items]
Net trade sales	1,319.2	1,207.6		3,739.7	3,098.2
Operating segments | Bedding Products
Segment Reporting Information [Line Items]
Net trade sales	664.1	589.8		1,808.6	1,491.0
Operating segments | Specialized Products
Segment Reporting Information [Line Items]
Net trade sales	235.6	242.9		734.9	618.2
Operating segments | Furniture, Flooring & Textile Products
Segment Reporting Information [Line Items]
Net trade sales	419.5	374.9		1,196.2	989.0
Intersegment eliminations
Segment Reporting Information [Line Items]
Net trade sales	15.6	13.6		45.1	36.1
EBIT	(0.4)	(0.7)		(0.6)	(3.7)
Depreciation and Amortization	1.6	3.4		7.9	9.7
Intersegment eliminations | Bedding Products
Segment Reporting Information [Line Items]
Net trade sales	11.4	10.0		32.4	23.6
Intersegment eliminations | Specialized Products
Segment Reporting Information [Line Items]
Net trade sales	1.0	0.8		2.6	2.0
Intersegment eliminations | Furniture, Flooring & Textile Products
Segment Reporting Information [Line Items]
Net trade sales	$ 3.2	$ 2.8		$ 10.1	$ 10.5