Debt - Additional Information (Detail) (USD $)	12 Months Ended
Sep. 30, 2013	Sep. 30, 2012
Revolving Credit Facility
Debt Instrument [Line Items]
Credit Facility Maximum Borrowing Capacity	$ 3,000,000,000	$ 3,000,000,000
Credit Facility Amount Outanding	0
Revolving Credit Facility \| Minimum
Debt Instrument [Line Items]
Credit Facility Interest Rate During Period	0.00%
Revolving Credit Facility \| Maximum
Debt Instrument [Line Items]
Credit Facility Interest Rate During Period	0.75%
Credit Facility Commitment Fee Percentage	0.05%
Commercial Paper
Debt Instrument [Line Items]
Commercial Paper Program, Amount Available	3,000,000,000	500,000,000
Commercial Paper Program, Maturity Period	P397D
Commercial Paper Program, Amount Outstanding	$ 0

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Period Type:	duration

Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:stringItemType
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Period Type:	duration

- Definition

Amount borrowed under the credit facility as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

Name:	us-gaap_LineOfCreditFacilityAmountOutstanding
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The effective interest rate at the end of the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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Data Type:	num:percentItemType
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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Commercial Paper, Amount Outstanding

+ References

No definition available.

+ Details

Name:	v_CommercialPaperAmountOutstanding
Namespace Prefix:	v_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Commercial Paper, Maximum Borrowing Capacity

+ References

No definition available.

+ Details

Name:	v_CommercialPaperMaximumBorrowingCapacity
Namespace Prefix:	v_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant