Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
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	4.7
Share-based compensation expense	$ 13.1	$ 10.2	$ 7.6
Tax benefit from share-based compensation expense	$ 2.0	$ 1.9	$ 1.5
Vesting period	3 years
Weighted average fair value of options granted (usd per share)	$ 17.44	$ 12.64	$ 13.54
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)	$ 31.53
Exercisable at end of year (shares)	0.7	0.8	1.0
Stock options, expected to vest (shares)	0.3
Stock options outstanding, aggregate intrinsic value	$ 47.4
Stock options exercisable, aggregate intrinsic value	37.3
Stock options exercised during the period, total intrinsic value	9.9	$ 9.7	$ 22.7
Tax benefit from stock options exercised	2.4	2.5	5.7
Proceeds from stock compensation activity	3.9	0.2	4.2
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense related to share-based compensation plans	2.2	2.1	2.0
Unrecognized compensation cost	$ 3.1
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	$ 4.3	3.8	2.6
Unrecognized compensation cost	$ 3.6
Weighted-average recognition period for unrecognized compensation cost	1 year 9 months 18 days
Grant-date fair value of awards vested	$ 3.5	2.1	1.9
PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense related to share-based compensation plans	6.6	4.3	3.0
Unrecognized compensation cost, performance share units	$ 5.6
Weighted-average recognition period for unrecognized compensation cost	1 year 7 months 6 days
Grant-date fair value of awards vested	$ 4.6	$ 4.0	$ 2.6
Minimum \| PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	0.00%
Maximum \| PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	200.00%
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	132.00%

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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

+ Details

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