CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) shares in Millions, $ in Millions		Total		Series B Preferred Stock	Series C Preferred Stock	Class A common stock		Class B common stock		Class C common stock		Preferred Stock	Preferred Stock Series B Preferred Stock		Preferred Stock Series C Preferred Stock		Common Stock Class A common stock	Common Stock Class B common stock	Common Stock Class C common stock	Treasury Stock	Right to Recover for Covered Losses	Additional Paid-In Capital	Accumulated Income	Accumulated Other Comprehensive Income (Loss)
Beginning Balance (in shares) at Sep. 30, 2014																	1,978	245	22
Beginning Balance at Sep. 30, 2014		$ 27,413																				$ 18,299	$ 9,131	$ (17)
Net income		6,328	[1]			$ 5,044	[1]	$ 1,045	[1]	$ 224	[1]												6,328
Other comprehensive loss, net of tax		(57)																						(57)
Comprehensive income		6,271
Conversion of class C common stock upon sale into public market (in shares)																	11		(2)
Issuance and vesting of restricted stock and performance-based shares (in shares)																	4
Share-based compensation, net of forfeitures (Note 15) (in shares)	[2]																(1)
Share-based compensation, net of forfeitures (Note 15)		187																				187
Restricted stock and performance-based shares settled in cash for taxes (in shares)																	(1)
Restricted stock and performance-based shares settled in cash for taxes		(108)																				(108)
Excess tax benefit for share-based compensation		84																				84
Cash proceeds from issuance of common stock under employee equity plans (in shares)																	3
Cash proceeds from issuance of common stock under employee equity plans		82																				82
Cash dividends declared and paid, at a quarterly amount of $0.165 in FY 2017, $0.14 in FY 2016, and $0.12 in FY 2015 per as-converted share		(1,177)																					(1,177)
Repurchase of class A common stock (Note 13) (in shares)																	(44)
Repurchase of class A common stock (Note 13)		(2,910)																				(471)	(2,439)
Ending Balance (in shares) at Sep. 30, 2015													0	[3]	0	[3]	1,950	245	20
Ending Balance at Sep. 30, 2015		29,842										$ 0								$ 0	$ 0	18,073	11,843	(74)
Net income		5,991	[1],[4]			$ 4,738	[1],[4]	1,006	[1],[4]	185	[1],[4]												5,991
Other comprehensive loss, net of tax		(384)																						(384)
Comprehensive income		5,607
Issuance of preferred stock (Note 2 and Note 13) (in shares)	[3]												2		3
Issuance of preferred stock (Note 2 and Note 13)		5,717										5,717
VE territory covered losses incurred (Note 3)		(34)																			(34)
Class C common stock held by Visa Europe, a wholly-owned subsidiary of Visa Inc. (Note 13) (in shares)																			1
Class C common stock held by Visa Europe, a wholly-owned subsidiary of Visa Inc. (Note 13)		0																		170
Conversion of class C common stock upon sale into public market (in shares)																	8		(2)
Issuance and vesting of restricted stock and performance-based shares (in shares)																	2
Share-based compensation, net of forfeitures (Note 15) (in shares)	[5]																0
Share-based compensation, net of forfeitures (Note 15)		221																				221
Restricted stock and performance-based shares settled in cash for taxes (in shares)																	(1)
Restricted stock and performance-based shares settled in cash for taxes		(92)																				(92)
Excess tax benefit for share-based compensation		63																				63
Cash proceeds from issuance of common stock under employee equity plans (in shares)																	3
Cash proceeds from issuance of common stock under employee equity plans		95																				95
Cash dividends declared and paid, at a quarterly amount of $0.165 in FY 2017, $0.14 in FY 2016, and $0.12 in FY 2015 per as-converted share		(1,350)																					(1,350)
Repurchase of class A common stock (Note 13) (in shares)						(91)	[6],[7]										(91)
Repurchase of class A common stock (Note 13)		(6,987)				$ (6,987)	[7]															(965)	(6,022)
Ending Balance (in shares) at Sep. 30, 2016													2	[8]	3	[8]	1,871	245	17
Ending Balance at Sep. 30, 2016		32,912										5,717	$ 2,516		$ 3,201					(170)	(34)	17,395	10,462	(458)
Net income		6,699	[1]			$ 5,170	[1]	$ 1,134	[1]	$ 163	[1]												6,699
Other comprehensive loss, net of tax		1,336																						1,336
Comprehensive income		8,035
Recovery through conversion rate adjustment (Note 3 and Note 13)				$ 190	$ 1							(191)	$ (190)		$ (1)						191
VE territory covered losses incurred (Note 3)		(209)																			(209)
Charitable contribution of Visa Inc. shares (Note 13 and Note 18) (in shares)																	2
Charitable contribution of Visa Inc. shares (Note 13 and Note 18)		170																		170
Treasury Stock Appreciation, Net Of Tax		$ 14																				14
Conversion of class C common stock upon sale into public market (in shares)		2,350	[9]			1,818	[9],[10]	405	[9]	51	[9]						17		(4)
Issuance and vesting of restricted stock and performance-based shares (in shares)																	2
Share-based compensation, net of forfeitures (Note 15) (in shares)	[11]																0
Share-based compensation, net of forfeitures (Note 15)		$ 235																				235
Restricted stock and performance-based shares settled in cash for taxes (in shares)																	(1)
Restricted stock and performance-based shares settled in cash for taxes		(76)																				(76)
Cash proceeds from issuance of common stock under employee equity plans (in shares)																	4
Cash proceeds from issuance of common stock under employee equity plans		149																				149
Cash dividends declared and paid, at a quarterly amount of $0.165 in FY 2017, $0.14 in FY 2016, and $0.12 in FY 2015 per as-converted share		(1,579)																					(1,579)
Repurchase of class A common stock (Note 13) (in shares)						(77)	[6],[7]										(77)
Repurchase of class A common stock (Note 13)		(6,891)				$ (6,891)	[7]															(817)	(6,074)
Ending Balance (in shares) at Sep. 30, 2017													2	[8]	3	[8]	1,818	245	13
Ending Balance at Sep. 30, 2017		$ 32,760										$ 5,526	$ 2,326		$ 3,200					$ 0	$ (52)	$ 16,900	$ 9,508	$ 878

[1] Net income is allocated based on proportional ownership on an as-converted basis. The weighted-average number of shares of as-converted class B common stock used in the income allocation was 405 million for fiscal 2017, 2016 and 2015. The weighted-average number of shares of as-converted class C common stock used in the income allocation was 58 million, 75 million and 87 million for fiscal 2017, 2016 and 2015, respectively. The weighted-average number of shares of preferred stock, included within participating securities, was 33 million of as-converted UK&I preferred stock, and 44 million of as-converted Europe preferred stock for fiscal 2017.

[2] Decrease in Class A common stock related to forfeitures of restricted stock awards.

[3] Series B and C preferred stock are alternatively referred to as UK&I and Europe preferred stock, respectively.

[4] See Note 2—Visa Europe.

[5] Decrease in Class A common stock related to forfeitures of restricted stock awards is less than one million shares.

[6] All shares repurchased in the open market have been retired and constitute authorized but unissued shares.

[7] Shares repurchased in the open market reflect repurchases settled during fiscal 2017. These amounts include repurchases traded but not yet settled on or before September 30, 2016 for fiscal 2017 or September 30, 2015 for fiscal 2016 and exclude repurchases traded but not yet settled on or before September 30, 2017 for fiscal 2017 or September 30, 2016 for fiscal 2016.

[8] Series B and C preferred stock are alternatively referred to as UK&I and Europe preferred stock, respectively.

[9] Figures in the table may not recalculate exactly due to rounding. As-converted class A common stock is calculated based on unrounded numbers.

[10] Class A common stock shares outstanding reflect repurchases settled on or before September 30, 2017.

[11] Decrease in Class A common stock related to forfeitures of restricted stock awards is less than one million shares.