Segment Analysis - Narrative (Details)	6 Months Ended
	Mar. 31, 2024 employee country market currency
Segment Reporting Information [Line Items]
Number of employees | employee	4,300
Number of countries in which entity operates (more than)	180
Number of global financial markets (more than) | market	18,000
Payments
Segment Reporting Information [Line Items]
Number of countries in which entity operates (more than)	180
Number of different types of foreign currencies (more than) | currency	140