Reportable Business Segments (Depreciation and Amortization Expense by Segment) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Total depreciation and amortization	$ 72.6	$ 71.1	$ 66.0
Residential Heating and Cooling [Member]
Segment Reporting Information [Line Items]
Total depreciation and amortization	28.5	30.0	26.6
Commercial Heating and Cooling [Member]
Segment Reporting Information [Line Items]
Total depreciation and amortization	13.5	12.5	8.6
Refrigeration [Member]
Segment Reporting Information [Line Items]
Total depreciation and amortization	7.8	7.9	8.9
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Total depreciation and amortization	$ 22.8	$ 20.7	$ 21.9