Reportable Business Segments (Assets by Segment) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Total assets	$ 2,032.5	$ 2,034.9	$ 1,817.2
Residential Heating and Cooling [Member]
Segment Reporting Information [Line Items]
Total assets	1,034.6	1,055.7	837.4
Commercial Heating and Cooling [Member]
Segment Reporting Information [Line Items]
Total assets	366.5	409.0	349.5
Refrigeration [Member]
Segment Reporting Information [Line Items]
Total assets	387.9	393.3	462.9
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Total assets	$ 243.5	$ 176.9	$ 167.4