Income Taxes	9 Months Ended
Income Taxes	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes We are subject to both direct and indirect taxation in the U.S. and various states and foreign jurisdictions. We are under examination by certain tax authorities for the 2008 to 2016 tax years. We believe that adequate amounts have been reserved for any adjustments that may ultimately result from these or other examinations. The material jurisdictions where we are subject to potential examination by tax authorities for tax years after 2007 include, among others, the U.S. (Federal and California), Germany, Korea, Israel, Switzerland, United Kingdom and Canada. Although the timing of the resolution and/or closure of audits is highly uncertain, it is reasonably possible that the balance of gross unrecognized tax benefits could significantly change in the next 12 months. However, given the number of years remaining subject to examination and the number of matters being examined, we are unable to estimate the full range of possible adjustments to the balance of gross unrecognized tax benefits. As a result of the realignment of our legal structure in 2016 and 2017, we no longer benefit from tax rulings previously concluded in several different jurisdictions. Without the benefit of the rulings, the noncash tax impacts of the realignment in our foreign eBay and Classifieds platforms have increased our income tax rate in certain foreign jurisdictions, most significantly Switzerland. The higher rate results from eBay being subject to a higher enacted tax rate for the foreseeable future. While our tax rate is higher, the realignment allows us to achieve certain foreign cash tax benefits due to the step-up in tax basis achieved in certain foreign jurisdictions. We expect these cash tax benefits to remain consistent, subject to the performance of our foreign platforms, for a period in excess of 10 years. The realignment is expected to be substantially complete by the end of 2018 and primarily impact our international entities. However, U.S. tax reform and the new U.S. minimum tax on foreign earnings will reduce our expected consolidated cash tax benefits. On December 22, 2017, the Tax Cuts and Jobs Act (the “Act” or “U.S. tax reform”) was enacted. U.S. tax reform, among other things, reduces the U.S. federal income tax rate from 35% to 21% in 2018, institutes a dividends received deduction for foreign earnings with a related tax for the deemed repatriation of unremitted foreign earnings and creates a new U.S. minimum tax on earnings of foreign subsidiaries. We recognized a provisional income tax charge of $3.1 billion in the fourth quarter of 2017, which was included as a component of the income tax provision on our condensed consolidated statement of income. We computed the amount based on information available to us, including our expectation that existing foreign basis differences will affect the amount of U.S. minimum tax upon reversal; however, there is still uncertainty as to the application of the Act. As of September 30, 2018, we have not yet completed our analysis of the components of the tax computation, including a complete reconciliation of the book and tax bases in our foreign subsidiaries. As we complete our analysis of U.S. tax reform, we may make adjustments to the provisional amounts, which may materially impact our provision for income taxes from continuing operations in the period in which the adjustments are made. We expect to complete our analysis by the fourth quarter of 2018. During the third quarter of 2018, we recorded an immaterial increase to the provisional amount recorded in the fourth quarter of 2017. On October 11, 2018, we received a favorable tax ruling in connection with the ongoing realignment of our legal structure. The ruling will result in a reduction of the provisional amounts recorded in the fourth quarter of 2017 as a result of U.S. tax reform for the deferred income tax effects of the Act. Therefore, we expect to record a $389 million income tax benefit related to this matter in the fourth quarter of 2018. In 2018, certain foreign earnings will not be subject to U.S. federal income tax on a current basis as a result of differences between U.S. GAAP and U.S. tax treatment. Management intends to indefinitely reinvest those earnings. The amount expected to be indefinitely reinvested in 2018 is between $200 million and $300 million. The related unrecognized deferred tax liability would be approximately 24% of the indefinitely reinvested earnings. On July 27, 2015, in Altera Corp. v. Commissioner, the U.S. Tax Court issued an opinion invalidating the regulations relating to the treatment of stock-based compensation expense in an intercompany cost-sharing arrangement. A final decision was issued by the Tax Court in December 2015. The IRS appealed the decision in June 2016. On July 24, 2018, the Ninth Circuit Federal Court issued a decision that was subsequently withdrawn to allow time for a reconstituted panel to confer on the appeal. Due to the uncertainty surrounding the status of the current regulations, questions related to the scope of potential benefits or obligations, and the risk of the Tax Court’s decision being overturned upon appeal, we have not recorded any benefit or expense as of September 30, 2018. We will continue to monitor ongoing developments and potential impacts to our condensed consolidated financial statements.