Collateral (Detail) - USD ($) $ in Millions		Sep. 30, 2016	Sep. 30, 2015
Business Acquisition [Line Items]
Cash equivalents		$ 1,295	$ 1,023
Pledged securities at market value		170	154
Letters of credit		1,311	1,178
Guarantees		1,418	971
Total		4,194	$ 3,326
Visa Europe
Business Acquisition [Line Items]
Cash equivalents	[1]	294
Pledged securities at market value		0
Letters of credit		144
Guarantees		375
Total		$ 813

[1] Cash collateral held by Visa Europe is not included on the Company's consolidated balance sheet as its clients retain beneficial ownership and the cash is only accessible to the Company in the event of default by the client on its settlement obligations.