Nature of Operations and Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2021
Accounting Policies [Abstract]
Nature of Operations and Summary of Significant Accounting Policies	Nature of Operations and Summary of Significant Accounting Policies Nature of Operations Google was incorporated in California in September 1998 and re-incorporated in the State of Delaware in August 2003. In 2015, we implemented a holding company reorganization, and as a result, Alphabet became the successor issuer to Google. We generate revenues by delivering relevant, cost-effective online advertising, cloud-based solutions that provide customers with platforms, collaboration tools and services, and sales of other products and services, such as apps and in-app purchases, digital content and subscriptions for digital content, and hardware. Basis of Consolidation The consolidated financial statements of Alphabet include the accounts of Alphabet and entities consolidated under the variable interest and voting models. All intercompany balances and transactions have been eliminated. Unaudited Interim Financial Information The Consolidated Balance Sheet as of June 30, 2021, the Consolidated Statements of Income for the three and six months ended June 30, 2020 and 2021, the Consolidated Statements of Comprehensive Income for the three and six months ended June 30, 2020 and 2021, the Consolidated Statements of Stockholders' Equity for the three and six months ended June 30, 2020 and 2021 and the Consolidated Statements of Cash Flows for the six months ended June 30, 2020 and 2021 are unaudited. These unaudited interim consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States ("GAAP"). In our opinion, the unaudited interim consolidated financial statements include all adjustments of a normal recurring nature necessary for the fair presentation of our financial position as of June 30, 2021, our results of operations for the three and six months ended June 30, 2020 and 2021, and our cash flows for the six months ended June 30, 2020 and 2021. The results of operations for the three and six months ended June 30, 2021 are not necessarily indicative of the results to be expected for the year ending December 31, 2021. These unaudited interim consolidated financial statements should be read in conjunction with the consolidated financial statements and the related notes included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2020 filed with the SEC. Use of Estimates Preparation of consolidated financial statements in conformity with GAAP requires us to make estimates and assumptions that affect the amounts reported and disclosed in the financial statements and the accompanying notes. Actual results could differ materially from these estimates. On an ongoing basis, we evaluate our estimates, including those related to the allowance for credit losses, fair values of financial instruments, intangible assets and goodwill, useful lives of intangible assets and property and equipment, income taxes, and contingent liabilities, among others. We base our estimates on assumptions, both historical and forward looking, that are believed to be reasonable, the results of which form the basis for making judgments about the carrying values of assets and liabilities. The allowance for credit losses on accounts receivable was $789 million and $579 million as of December 31, 2020 and June 30, 2021, respectively. Change in Accounting Estimate In January 2021, we completed an assessment of the useful lives of our servers and network equipment and adjusted the estimated useful life of our servers from three years to four years and the estimated useful life of certain network equipment from three years to five years. This change in accounting estimate was effective beginning in fiscal year 2021. Based on the carrying value of servers and certain network equipment as of December 31, 2020, and those acquired during the six months ended June 30, 2021, the effect of this change in estimate was a reduction in depreciation expense of $721 million and $1.6 billion and an increase in net income of $561 million and $1.2 billion, or $0.84 and $1.81 per basic and $0.83 and $1.78 per diluted share, for the three and six months ended June 30, 2021, respectively. Prior Period Reclassifications Certain amounts in prior periods have been reclassified to conform with current period presentation.