Goodwill and Other Intangible Assets - Schedule of Changes in Carrying Amount of Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Goodwill [Roll Forward]
Beginning balance	$ 761.7	$ 633.4
Currency translation adjustment	2.8	(10.1)
Acquisitions		138.4
Acquisition adjustments	(53.9)
Ending balance	710.6	761.7
North America
Goodwill [Roll Forward]
Beginning balance	586.7	574.9
Currency translation adjustment	4.8	(8.7)
Acquisitions		20.5
Acquisition adjustments	0.0
Ending balance	591.5	586.7
Rest of World
Goodwill [Roll Forward]
Beginning balance	175.0	58.5
Currency translation adjustment	(2.0)	(1.4)
Acquisitions		117.9
Acquisition adjustments	(53.9)
Ending balance	$ 119.1	$ 175.0

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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+ Details

SMITH A O CORP 10-K