Revenue Recognition (Narrative) (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenues	$ 914,000,000.0	$ 1,055,000,000.0	$ 941,300,000	$ 723,800,000	$ 885,000,000.0	$ 1,032,900,000	$ 1,099,100,000	$ 790,300,000	$ 3,634,100,000	$ 3,807,200,000	$ 3,883,900,000
Contract with Customer, Liability, Revenue Recognized									7,200,000	3,300,000	4,800,000
Residential Heating and Cooling [Member]
Revenues									2,361,500,000	2,291,100,000	2,225,000,000.0
Commercial Heating and Cooling [Member]
Revenues									800,900,000	947,400,000	900,700,000
Revenue from Contract with Customer, Excluding Assessed Tax									0.85	0.86	0.86
Refrigeration [Member]
Revenues									471,700,000	568,700,000	758,200,000
Sales Channel, Directly to Consumer [Member] | Residential Heating and Cooling [Member]
Revenue from Contract with Customer, Excluding Assessed Tax									0.75	0.75	0.76
Service [Member] | Refrigeration [Member]
Revenue from Contract with Customer, Excluding Assessed Tax									$ 0.01	$ 0.01	$ 0.01