v3.25.1

Stock Based Compensation - Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2025 USD ($) shares	Mar. 31, 2024 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expense	$ 6.1	$ 8.3
Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Number of units granted (in shares) \| shares	209,366	189,792
Value of units share units granted	$ 13.7	$ 15.6
Stock based compensation expense	$ 5.5	$ 7.8
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Number of units granted (in shares) \| shares	35,365	28,390
Value of units share units granted	$ 2.3	$ 2.3
Stock based compensation expense	$ 0.5	$ 0.3
Performance Shares \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Potential payouts range	0
Performance Shares \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Potential payouts range	1.50
A.O. Smith Combined Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for granting of options or share units (in shares) \| shares	2,079,233

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Fair Value

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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SMITH A O CORP 10-Q