Segment and Geographic Information - Narrative (Details)	12 Months Ended
	Sep. 30, 2023 employee currency market country
Segment Reporting Information [Line Items]
Number of employees | employee	4,000
Number of countries in which entity operates (more than)	180
Retail
Segment Reporting Information [Line Items]
Number of countries in which entity operates (more than)	180
Number of global financial markets | market	18,000
Global 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