Revenue Recognition (Narrative) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Disaggregation of Revenue [Line Items]
Contract with Customer, Liability, Revenue Recognized	$ 3,700,000	$ 1,600,000
Residential Heating and Cooling [Member] | Sales Channel, Directly to Consumer [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	0.66	0.67
Commercial Heating and Cooling | Equipment Sales
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 0.80	$ 0.83