Goodwill - Goodwill by Segment (Details) - USD ($) $ in Millions	Mar. 31, 2023	Sep. 30, 2022
Goodwill [Line Items]
Total Goodwill	$ 59.4	$ 58.2
Commercial
Goodwill [Line Items]
Total Goodwill	33.8	32.6
Institutional
Goodwill [Line Items]
Total Goodwill	9.8	9.8
Retail
Goodwill [Line Items]
Total Goodwill	5.8	5.8
Global Payments
Goodwill [Line Items]
Total Goodwill	$ 10.0	$ 10.0