Subsequent Event (Details) - USD ($) $ in Millions	Aug. 31, 2023	Jun. 30, 2023	Aug. 31, 2022	Aug. 31, 2020	May 31, 2019	Feb. 28, 2018	Aug. 31, 2017
Subsequent Event [Line Items]
Share repurchase program, increase in shares authorized for repurchase			$ 78.7	$ 58.5	$ 50.0	$ 30.0
Share repurchase program, approved amount							$ 30.0
Treasury stock, carrying basis		$ 52.4		$ 247.2
Subsequent Event
Subsequent Event [Line Items]
Share repurchase program, increase in shares authorized for repurchase	$ 47.6
Share repurchase program, approved amount	294.8
Treasury stock, carrying basis	$ 100.0