Goodwill (Details) - USD ($) $ in Millions	Mar. 31, 2025	Sep. 30, 2024
Goodwill [Line Items]
Total Goodwill	$ 67.8	$ 61.0
Commercial
Goodwill [Line Items]
Total Goodwill	38.1	33.3
Institutional
Goodwill [Line Items]
Total Goodwill	11.8	9.8
Self-Directed/Retail
Goodwill [Line Items]
Total Goodwill	7.9	7.9
Payments
Goodwill [Line Items]
Total Goodwill	$ 10.0	$ 10.0

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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+ Details

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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