Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized under stock compensation plan	11.0
Shares available for grant under stock compensation plan	4.2
Share-based compensation expense	$ 15.6	$ 13.1	$ 10.2
Tax benefit from share-based compensation expense	$ 2.3	$ 2.0	$ 1.9
Vesting period	3 years
Weighted average fair value of options granted (usd per share)	$ 29.34	$ 17.44	$ 12.64
Stock options, vested and expected to vest, outstanding (shares)	1.0
Stock options, vested and expected to vest, weighted average exercise price (usd per share)	$ 36.49
Exercisable at end of year (shares)	0.8	0.7	0.8
Stock options, expected to vest (shares)	0.2
Stock options outstanding, aggregate intrinsic value	$ 56.7
Stock options exercisable, aggregate intrinsic value	49.1
Stock options exercised during the period, total intrinsic value	6.5	$ 9.9	$ 9.7
Tax benefit from stock options exercised	5.1	3.9
Proceeds from stock compensation activity	2.0	3.9	0.2
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense related to share-based compensation plans	2.3	2.2	2.1
Unrecognized compensation cost	$ 3.4
Weighted-average recognition period for unrecognized compensation cost	1 year 10 months 24 days
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense related to share-based compensation plans	$ 3.9	4.3	3.8
Unrecognized compensation cost	$ 4.0
Weighted-average recognition period for unrecognized compensation cost	1 year 9 months 18 days
Grant-date fair value of awards vested	$ 2.4	3.5	2.1
PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense related to share-based compensation plans	9.4	6.6	4.3
Unrecognized compensation cost, performance share units	$ 6.7
Weighted-average recognition period for unrecognized compensation cost	1 year 6 months
Grant-date fair value of awards vested	$ 8.7	4.6	4.0
Equity Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Tax benefit from stock options exercised	$ 1.6	$ 2.4	$ 2.5
Maximum \| PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Percentage with TSR Modifier	240.00%
Performance-based Restricted Stock Units, 2022 Grants [Member] \| PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share units performance period	3 years
Performance-based Restricted Stock Units, 2021 Grants [Member] \| PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share units performance period	3 years
Performance-based Restricted Stock Units, 2020 Grants \| PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share units performance period	3 years
Vesting percentage	190.00%	132.00%	125.00%
Performance-based Restricted Stock Units, 2020 Grants \| Performance Shares with TSR
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	228.00%

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-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

+ References

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