Segment Information (Average Assets For Segments) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2018
Segment Reporting Information [Line Items]
Assets	$ 3,382.0	$ 3,550.8	$ 2,984.1	$ 3,551.5
Additions to Property, Plant and Equipment	159.6	159.4	124.0
Acquired Companies’ Long-Lived Assets	85.4	47.9	24.9
Depreciation And Amortization	136.1	125.9	115.4
Residential Products
Segment Reporting Information [Line Items]
Assets	609.4	554.6	527.2
Additions to Property, Plant and Equipment	48.0	60.5	32.4
Acquired Companies’ Long-Lived Assets	6.0	33.6	11.2
Depreciation And Amortization	46.6	45.8	42.9
Industrial Products
Segment Reporting Information [Line Items]
Assets	163.8	150.0	147.4
Additions to Property, Plant and Equipment	9.6	14.3	10.1
Acquired Companies’ Long-Lived Assets	0.0	0.0	0.0
Depreciation And Amortization	10.3	10.2	11.8
Furniture Products
Segment Reporting Information [Line Items]
Assets	279.8	245.7	219.4
Additions to Property, Plant and Equipment	19.7	20.2	16.6
Acquired Companies’ Long-Lived Assets	0.0	14.3	0.0
Depreciation And Amortization	17.4	16.2	14.4
Specialized Products
Segment Reporting Information [Line Items]
Assets	342.5	271.7	248.7
Additions to Property, Plant and Equipment	45.0	51.7	42.2
Acquired Companies’ Long-Lived Assets	79.4	0.0	13.7
Depreciation And Amortization	39.0	31.2	29.7
Average current liabilities included in segment numbers above
Segment Reporting Information [Line Items]
Assets	661.8	557.0	495.9
Additions to Property, Plant and Equipment	0.0	0.0	0.0
Acquired Companies’ Long-Lived Assets	0.0	0.0	0.0
Depreciation And Amortization	0.0	0.0	0.0
Unallocated assets and other
Segment Reporting Information [Line Items]
Assets	1,278.0	1,693.1	1,378.5
Additions to Property, Plant and Equipment	37.3	12.7	22.7
Acquired Companies’ Long-Lived Assets	0.0	0.0	0.0
Depreciation And Amortization	22.8	22.5	16.6
Difference between average assets and year-end balance sheet
Segment Reporting Information [Line Items]
Assets	46.7	78.7	(33.0)
Additions to Property, Plant and Equipment	0.0	0.0	0.0
Acquired Companies’ Long-Lived Assets	0.0	0.0	0.0
Depreciation And Amortization	$ 0.0	$ 0.0	$ 0.0

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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