Stock-Based Compensation Plans - RSUs and PSUs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based compensation plans
Shares authorized for future grant	1,539,738
Restricted stock units (RSUs) and performance stock units (PSUs)
Additional share-based compensation disclosures
Tax benefit realized from RSU and PSU settlements	$ 7.7	$ 8.0	$ 6.8
Vesting period (in years)	3 years	3 years	3 years