SEGMENT INFORMATION - Average Assets for Segments (Details) - USD ($) $ in Millions	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Assets	$ 4,953.8	$ 3,517.9	$ 3,382.0
Operating segments | Residential Products
Segment Reporting Information [Line Items]
Assets	771.5		609.4
Operating segments | Industrial Products
Segment Reporting Information [Line Items]
Assets	168.3		163.8
Operating segments | Furniture Products
Segment Reporting Information [Line Items]
Assets	259.4		279.8
Operating segments | Specialized Products
Segment Reporting Information [Line Items]
Assets	357.7		342.5
Operating segments | Average current liabilities included in segment numbers above
Segment Reporting Information [Line Items]
Assets	765.2		661.8
Unallocated assets
Segment Reporting Information [Line Items]
Assets	2,569.3		1,278.0
Difference between average assets and period-end balance sheet
Segment Reporting Information [Line Items]
Assets	$ 62.4		$ 46.7