Summary of Significant Accounting Policies	9 Months Ended
Jun. 30, 2018
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Note 1—Summary of Significant Accounting Policies Organization. Visa Inc. (“Visa” or the “Company”) is a global payments technology company that enables fast, secure and reliable electronic payments across more than 200 countries and territories. Visa and its wholly-owned consolidated subsidiaries, including Visa U.S.A. Inc. (“Visa U.S.A.”), Visa International Service Association (“Visa International”), Visa Worldwide Pte. Limited, Visa Europe Limited (“Visa Europe”), Visa Canada Corporation, Visa Technology & Operations LLC and CyberSource Corporation, operate one of the world’s largest retail electronic payments networks — VisaNet — which facilitates authorization, clearing and settlement of payment transactions and enables the Company to provide its financial institution and merchant clients a wide range of products, platforms and value-added services. VisaNet also offers fraud protection for account holders and assured payment for merchants. Visa is not a bank and does not issue cards, extend credit or set rates and fees for account holders on Visa products. In most cases, account holder and merchant relationships belong to, and are managed by, Visa’s financial institution clients. Consolidation and basis of presentation. The accompanying unaudited consolidated financial statements include the accounts of Visa and its consolidated entities and are presented in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). The Company consolidates its majority-owned and controlled entities, including variable interest entities (“VIEs”) for which the Company is the primary beneficiary. The Company’s investments in VIEs have not been material to its consolidated financial statements as of and for the periods presented. All significant intercompany accounts and transactions are eliminated in consolidation. The accompanying unaudited consolidated financial statements are presented in accordance with the U.S. Securities and Exchange Commission (SEC) requirements for Quarterly Reports on Form 10-Q and, consequently, do not include all of the annual disclosures required by U.S. GAAP. Reference should be made to the Visa Annual Report on Form 10-K for the year ended September 30, 2017 for additional disclosures, including a summary of the Company’s significant accounting policies. In the opinion of management, the accompanying unaudited consolidated financial statements include all normal recurring adjustments necessary for a fair presentation of the Company’s financial position, results of operations and cash flows for the interim periods presented. Recently Issued and Adopted Accounting Pronouncements. In May 2014, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2014-09, which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of goods or services to customers. The ASU replaces existing revenue recognition guidance in U.S. GAAP. Subsequently, the FASB also issued a series of amendments to the new revenue standard. The Company will adopt the standard effective October 1, 2018, and expects to adopt the standard using the modified retrospective transition method. The Company expects that the new standard will primarily impact recognition timing for certain fixed incentives and price discounts provided to clients, and the classification of certain client incentives between contra revenues and operating expenses. The impact of the new standard to future financial results is unknowable as it is not possible to estimate the impact to the recognition of new customer contracts which may be executed in future periods. The Company has completed an assessment of its existing customer contracts through June 30, 2018. Application of the new standard to consolidated financial statements for the first three quarters of fiscal 2018 would not have resulted in a material impact. The Company will continue to assess the impact of the new standard as new customer contracts are executed going forward. In March 2016, the FASB issued ASU 2016-05, which clarifies that a change in the counterparty to a derivative instrument that has been designated as the hedging instrument under Topic 815, Derivatives and Hedging, does not, in and of itself, require dedesignation of that hedging relationship provided that all other hedge accounting criteria continue to be met. The Company adopted the standard effective October 1, 2017. The adoption did not have a material impact on the consolidated financial statements. In March 2016, the FASB issued ASU 2016-06, which clarifies the requirements for assessing whether contingent call/put options that can accelerate the payment of principal on debt instruments are clearly and closely related to their debt hosts. An entity performing the assessment is required to assess the embedded call/put options solely in accordance with a four-step decision sequence. The Company adopted the standard effective October 1, 2017. The adoption did not have a material impact on the consolidated financial statements. In March 2016, the FASB issued ASU 2016-07, which eliminates the requirement that an entity retroactively adopt the equity method of accounting if an investment qualifies for use of the equity method as a result of an increase in the level of ownership or degree of influence. The equity method investor is required to add the cost of acquiring the additional interest in the investee to the current basis of the investor’s previously held interest and adopt the equity method of accounting as of the date the investment becomes qualified for equity method accounting. The Company adopted the standard effective October 1, 2017. The adoption did not have a material impact on the consolidated financial statements. In February 2018, the FASB issued ASU 2018-02, which allows a reclassification from accumulated other comprehensive income to retained earnings for adjustments to tax effects that were originally recorded in other comprehensive income due to changes in the U.S. federal corporate income tax rate resulting from the enactment of the U.S. tax reform legislation, commonly referred to as the Tax Cuts and Jobs Act (the “Tax Act”). The Company will adopt the standard effective October 1, 2019. The adoption is not expected to have a material impact on the consolidated financial statements. In March 2018, the FASB issued ASU 2018-05 to insert the SEC’s interpretive guidance from Staff Accounting Bulletin No. 118 into the income tax accounting codification under U.S. GAAP. The ASU permits companies to use provisional amounts for certain income tax effects of the Tax Act during a one-year measurement period. The provisional accounting impacts for the Company may change in future reporting periods until the accounting analysis is finalized, which will occur no later than the first quarter of fiscal 2019.

Note 1—Summary of Significant Accounting Policies

Organization. Visa Inc. (“Visa” or the “Company”) is a global payments technology company that enables fast, secure and reliable electronic payments across more than 200 countries and territories. Visa and its wholly-owned consolidated subsidiaries, including Visa U.S.A. Inc. (“Visa U.S.A.”), Visa International Service Association (“Visa International”), Visa Worldwide Pte. Limited, Visa Europe Limited (“Visa Europe”), Visa Canada Corporation, Visa Technology & Operations LLC and CyberSource Corporation, operate one of the world’s largest retail electronic payments networks — VisaNet — which facilitates authorization, clearing and settlement of payment transactions and enables the Company to provide its financial institution and merchant clients a wide range of products, platforms and value-added services. VisaNet also offers fraud protection for account holders and assured payment for merchants. Visa is not a bank and does not issue cards, extend credit or set rates and fees for account holders on Visa products. In most cases, account holder and merchant relationships belong to, and are managed by, Visa’s financial institution clients.

Consolidation and basis of presentation. The accompanying unaudited consolidated financial statements include the accounts of Visa and its consolidated entities and are presented in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). The Company consolidates its majority-owned and controlled entities, including variable interest entities (“VIEs”) for which the Company is the primary beneficiary. The Company’s investments in VIEs have not been material to its consolidated financial statements as of and for the periods presented. All significant intercompany accounts and transactions are eliminated in consolidation.

The accompanying unaudited consolidated financial statements are presented in accordance with the U.S. Securities and Exchange Commission (SEC) requirements for Quarterly Reports on Form 10-Q and, consequently, do not include all of the annual disclosures required by U.S. GAAP. Reference should be made to the Visa Annual Report on Form 10-K for the year ended September 30, 2017 for additional disclosures, including a summary of the Company’s significant accounting policies.

In the opinion of management, the accompanying unaudited consolidated financial statements include all normal recurring adjustments necessary for a fair presentation of the Company’s financial position, results of operations and cash flows for the interim periods presented.

Recently Issued and Adopted Accounting Pronouncements.

In May 2014, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2014-09, which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of goods or services to customers. The ASU replaces existing revenue recognition guidance in U.S. GAAP. Subsequently, the FASB also issued a series of amendments to the new revenue standard. The Company will adopt the standard effective October 1, 2018, and expects to adopt the standard using the modified retrospective transition method. The Company expects that the new standard will primarily impact recognition timing for certain fixed incentives and price discounts provided to clients, and the classification of certain client incentives between contra revenues and operating expenses. The impact of the new standard to future financial results is unknowable as it is not possible to estimate the impact to the recognition of new customer contracts which may be executed in future periods. The Company has completed an assessment of its existing customer contracts through June 30, 2018. Application of the new standard to consolidated financial statements for the first three quarters of fiscal 2018 would not have resulted in a material impact. The Company will continue to assess the impact of the new standard as new customer contracts are executed going forward.

In March 2016, the FASB issued ASU 2016-05, which clarifies that a change in the counterparty to a derivative instrument that has been designated as the hedging instrument under Topic 815, Derivatives and Hedging, does not, in and of itself, require dedesignation of that hedging relationship provided that all other hedge accounting criteria continue to be met. The Company adopted the standard effective October 1, 2017. The adoption did not have a material impact on the consolidated financial statements.

In March 2016, the FASB issued ASU 2016-06, which clarifies the requirements for assessing whether contingent call/put options that can accelerate the payment of principal on debt instruments are clearly and closely related to their debt hosts. An entity performing the assessment is required to assess the embedded call/put options solely in accordance with a four-step decision sequence. The Company adopted the standard effective October 1, 2017. The adoption did not have a material impact on the consolidated financial statements.

In March 2016, the FASB issued ASU 2016-07, which eliminates the requirement that an entity retroactively adopt the equity method of accounting if an investment qualifies for use of the equity method as a result of an increase in the level of ownership or degree of influence. The equity method investor is required to add the cost of acquiring the additional interest in the investee to the current basis of the investor’s previously held interest and adopt the equity method of accounting as of the date the investment becomes qualified for equity method accounting. The Company adopted the standard effective October 1, 2017. The adoption did not have a material impact on the consolidated financial statements.

In February 2018, the FASB issued ASU 2018-02, which allows a reclassification from accumulated other comprehensive income to retained earnings for adjustments to tax effects that were originally recorded in other comprehensive income due to changes in the U.S. federal corporate income tax rate resulting from the enactment of the U.S. tax reform legislation, commonly referred to as the Tax Cuts and Jobs Act (the “Tax Act”). The Company will adopt the standard effective October 1, 2019. The adoption is not expected to have a material impact on the consolidated financial statements.

In March 2018, the FASB issued ASU 2018-05 to insert the SEC’s interpretive guidance from Staff Accounting Bulletin No. 118 into the income tax accounting codification under U.S. GAAP. The ASU permits companies to use provisional amounts for certain income tax effects of the Tax Act during a one-year measurement period. The provisional accounting impacts for the Company may change in future reporting periods until the accounting analysis is finalized, which will occur no later than the first quarter of fiscal 2019.