Settlement Guarantee Management - Additional Information (Details) - USD ($) $ in Billions	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024
Settlement Guarantee Management [Abstract]
Maximum settlement exposure	$ 153.4
Average daily settlement exposure	91.2
Total collateral	$ 8.8	$ 7.7

The total of cash deposits and non-cash collateral assets including cash equivalents, pledged securities at market value, letters of credit and guarantees.

No definition available.

Name:	v_TotalCollateral
Namespace Prefix:	v_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant