Segment Analysis - Narrative (Details)	9 Months Ended
	Jun. 30, 2021 employee country currency market
Segment Reporting Information [Line Items]
Number of employees (more than) | employee	3,000
Number of countries in which entity operates (more than)	180
Retail Segment
Segment Reporting Information [Line Items]
Number of countries in which entity operates (more than)	130
Number of global financial markets (over) | market	15,000
Global Payments
Segment Reporting Information [Line Items]
Number of countries in which entity operates (more than)	170
Number of different types of foreign currencies (more than) | currency	140