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Acquisitions - Chasing Returns Ltd (Details) - USD ($) $ in Millions	1 Months Ended
	Aug. 31, 2021	Sep. 30, 2023	Sep. 30, 2022
Business Acquisition [Line Items]
Goodwill		$ 59.3	$ 58.2
Chasing Returns Limited
Business Acquisition [Line Items]
Purchase price	$ 6.0
Goodwill	3.6
Chasing Returns Limited \| Software programs/platforms
Business Acquisition [Line Items]
Finite-lived intangible assets acquired	$ 2.4