Visa Europe - Additional Information (Detail) $ / shares in Units, € in Billions				3 Months Ended		12 Months Ended
	Jun. 21, 2016 EUR (€) shares	Jun. 21, 2016 USD ($) shares		Sep. 30, 2016 USD ($) $ / shares	Sep. 30, 2016 USD ($) $ / shares	Sep. 30, 2016 USD ($) $ / shares		Sep. 30, 2015 USD ($) $ / shares	Sep. 30, 2014 USD ($)	Jun. 21, 2016 USD ($) $ / shares
Class of Stock [Line Items]
Convertible participating preferred stock issued in Visa Europe acquisition						$ 5,717,000,000		$ 0	$ 0
Average price of common stock (USD per share) | $ / shares										$ 77.33
Initial conversion rate of UK&I and Europe preferred stock into class A common or class A equivalent preferred stock	13.952									13.952
Revenues						15,082,000,000	[1]	13,880,000,000	12,702,000,000
Visa Europe Framework Agreement loss		$ (1,900,000,000)				(1,877,000,000)		0	0
Debt Instrument, Face Amount				$ 16,000,000,000	$ 16,000,000,000	16,000,000,000
Increase (Decrease) Liabilities Related to Investment Contracts, Fair Value Disclosure						255,000,000		$ 110,000,000
Foreign exchange gains related to euros						145,000,000
Gains related to currency forward contracts						74,000,000
Visa Europe
Class of Stock [Line Items]
Share capital of Visa Europe acquired (percent)	100.00%									100.00%
Up-front cash consideration	€ 12.2	13,882,000,000
Convertible participating preferred stock issued in Visa Europe acquisition	5.3	6,100,000,000
Contingent consideration | €	1.0
Accrued interest on contingent consideration | €	€ 0.0
Initial conversion rate of UK&I and Europe preferred stock into class A common or class A equivalent preferred stock	13.952									13.952
Revenues					$ 554,000,000
Acquisition related costs						96,000,000
Revenue since acquisition				$ 489,000,000
Visa Europe net income included in consolidated net income						299,000,000
Impact of acquisition on consolidated net income						(872,000,000)
Visa Europe Framework Agreement loss		$ (1,856,000,000)	[2]			$ (1,184,000,000)
Visa Europe | Class A equivalent preferred stock
Class of Stock [Line Items]
Preferred stock, par value | $ / shares										$ 0.0001
Conversion rate of U.K.&I preferred stock						100
Visa Europe | U.K.&I preferred stock
Class of Stock [Line Items]
Shares issued at closing (shares) | shares	2,480,466	2,480,466
Preferred stock, par value | $ / shares										0.0001
Visa Europe | Europe preferred stock
Class of Stock [Line Items]
Shares issued at closing (shares) | shares	3,156,823	3,156,823
Preferred stock, par value | $ / shares										$ 0.0001
Loss Sharing Agreement | Visa Europe
Class of Stock [Line Items]
Conversion rate of U.K.&I preferred stock	0	0
Loss sharing agreement										$ 1,000,000,000
Preferred Stock
Class of Stock [Line Items]
Preferred stock, par value | $ / shares				$ 0.0001	$ 0.0001	$ 0.0001		$ 0.0001
Preferred Stock | Visa Europe
Class of Stock [Line Items]
Shares issued at closing (shares) | shares	79,000,000	79,000,000
Operating Expense
Class of Stock [Line Items]
Acquisition related costs						$ 152,000,000
Professional Fees
Class of Stock [Line Items]
Acquisition related costs						60,000,000
General and Administrative Expenses
Class of Stock [Line Items]
Acquisition related costs						92,000,000
Visa Europe | Framework Agreement
Class of Stock [Line Items]
Revenues					$ 65,000,000	191,000,000		$ 255,000,000	$ 226,000,000
United Kingdom | Visa Europe
Class of Stock [Line Items]
Tax benefit upon remeasurement of deferred tax liability to reflect tax rate change					$ (88,000,000)	$ (88,000,000)

[1] The Company did not include Visa Europe's financial results in the Company's consolidated statements of operations from the acquisition date, June 21, 2016, through June 30, 2016 as the impact was immaterial. The Company's consolidated statement of operations for the year ended September 30, 2016 includes Visa Europe's financial results for the three months ended September 30, 2016. See Note 2—Acquisition of Visa Europe.

[2] the loss upon consummation of the transaction resulting from the effective settlement of the Framework Agreement between Visa and Visa Europe. The Visa Europe Framework Agreement provided Visa Europe with a perpetual, exclusive right to operate the Visa business in the Visa Europe region in exchange for a license fee paid to Visa. Under the terms of the Framework Agreement, the license fee paid by Visa Europe has increased modestly since inception in 2007, while the value of the Visa Europe business has increased at a greater rate. Using an income approach, the Company assessed the contractual terms and conditions of the Framework Agreement as compared to current market conditions and the historical and expected financial performance of Visa Europe. Based on the analysis performed, the Company determined that the terms were not at fair value as determined under U.S. GAAP at the Closing. The present value of the expected differential between payments required by the Framework Agreement and those that would be required if the contract were at fair value under U.S. GAAP was calculated over the Framework Agreement's contractual perpetual term, resulting in a loss of $1.9 billion recognized within operating expense in the Company's consolidated statement of operations during the third quarter of fiscal 2016, and a reduction to the purchase accounting consideration; and