Reportable Business Segments (Segment Data) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($) segment	Mar. 31, 2023 USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments | segment	2
Net sales
Net sales	$ 1,047.1	$ 1,049.4
Segment profit (loss)
Total segment profit	166.8	141.7
Reconciliation to Operating income:
Items in Losses (gains) and other expenses, net that are excluded from segment profit (loss)	0.0	2.2
Operating income	166.8	139.5
Home Comfort Solutions
Net sales
Net sales	674.6	681.0
Segment profit (loss)
Total segment profit	112.1	111.1
Building Climate Solutions
Net sales
Net sales	372.5	308.7
Segment profit (loss)
Total segment profit	78.2	50.0
Corporate and Other
Net sales
Net sales	0.0	59.7
Segment profit (loss)
Total segment profit	$ (23.5)	$ (19.4)