Reportable Business Segments (Key Financial Information by Segment) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Segment Reporting Information [Line Items]
Net sales	$ 1,072,600,000	$ 1,047,100,000
Cost of Goods Sold	744,100,000	707,100,000
Selling, general and administrative	171,300,000	170,700,000
Other (income) expense	1,600,000	2,500,000
Segment Profit And Loss	155,600,000	166,800,000
Revenue from transactions with major customers	0
Segment Reporting, Reconciling Item, Corporate Nonsegment
Segment Reporting Information [Line Items]
Net sales	0	0
Cost of Goods Sold	(300,000)	(300,000)
Selling, general and administrative	12,500,000	19,600,000
Other (income) expense	2,500,000	4,200,000
Segment Profit And Loss	(14,700,000)	(23,500,000)
Residential Heating and Cooling [Member]
Segment Reporting Information [Line Items]
Net sales	721,400,000	674,600,000
Residential Heating and Cooling [Member] | Operating Segments
Segment Reporting Information [Line Items]
Net sales	721,400,000	674,600,000
Cost of Goods Sold	507,200,000	466,100,000
Selling, general and administrative	98,400,000	97,500,000
Other (income) expense	(1,000,000.0)	(1,100,000)
Segment Profit And Loss	116,800,000	112,100,000
Commercial Heating and Cooling
Segment Reporting Information [Line Items]
Net sales	351,200,000	372,500,000
Commercial Heating and Cooling | Operating Segments
Segment Reporting Information [Line Items]
Net sales	351,200,000	372,500,000
Cost of Goods Sold	237,200,000	241,300,000
Selling, general and administrative	60,400,000	53,600,000
Other (income) expense	100,000	(600,000)
Segment Profit And Loss	$ 53,500,000	$ 78,200,000