Significant Accounting Policies (Policies)	3 Months Ended
Mar. 31, 2021
Accounting Policies [Abstract]
Basis of Presentation and Principles of Consolidation	Basis of Presentation and Principles of Consolidation The accompanying unaudited condensed consolidated interim financial statements include the accounts of Grubhub Inc. and have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) for interim financial information and in accordance with the rules and regulations of the United States Securities and Exchange Commission (the “SEC”). Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. These unaudited condensed consolidated interim financial statements include all wholly-owned subsidiaries and reflect all normal and recurring adjustments, as well as any other than normal adjustments, that are, in the opinion of management, necessary for a fair presentation of the results for the interim periods and should be read in conjunction with the consolidated financial statements and accompanying notes included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020 filed with the SEC on March 1, 2021 (the “2020 Form 10-K”). All significant intercompany transactions have been eliminated in consolidation. Operating results for the three months ended March 31, 2021 are not necessarily indicative of the results that may be expected for the fiscal year ending December 31, 2021.
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in accordance with GAAP requires management to make certain estimates, judgments and assumptions that affect the reported amounts of assets and liabilities and the related disclosures at the date of the financial statements, as well as the reported amounts of revenue and expenses during the periods presented. These estimates, judgments and assumptions take into account historical and forward-looking factors that the Company believes are reasonable including, but not limited to, the potential impacts arising from the COVID-19 pandemic and measures implemented to prevent its spread. As the extent and duration of the impacts from the COVID-19 pandemic remain unclear, the Company’s estimates and assumptions may evolve as conditions change. Significant items subject to such estimates, judgments and assumptions include revenue recognition, website and internal-use software development costs, goodwill, valuation and recoverability of intangible assets with finite lives and other long-lived assets, stock-based compensation, and income taxes. Actual results could differ significantly from these estimates.
Changes in Accounting Principle and Recently Issued Accounting Pronouncements	Changes in Accounting Principle There have been no material changes to the Company’s significant accounting policies described in the 2020 Form 10-K. Recently Issued Accounting Pronouncements There were no recently issued accounting pronouncements that had or are expected to have a material impact on our financial statements.

Significant Accounting Policies (Policies)

3 Months Ended

Mar. 31, 2021

Basis of Presentation and Principles of Consolidation

The accompanying unaudited condensed consolidated interim financial statements include the accounts of Grubhub Inc. and have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) for interim financial information and in accordance with the rules and regulations of the United States Securities and Exchange Commission (the “SEC”). Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. These unaudited condensed consolidated interim financial statements include all wholly-owned subsidiaries and reflect all normal and recurring adjustments, as well as any other than normal adjustments, that are, in the opinion of management, necessary for a fair presentation of the results for the interim periods and should be read in conjunction with the consolidated financial statements and accompanying notes included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020 filed with the SEC on March 1, 2021 (the “2020 Form 10-K”). All significant intercompany transactions have been eliminated in consolidation. Operating results for the three months ended March 31, 2021 are not necessarily indicative of the results that may be expected for the fiscal year ending December 31, 2021.

Use of Estimates

The preparation of condensed consolidated financial statements in accordance with GAAP requires management to make certain estimates, judgments and assumptions that affect the reported amounts of assets and liabilities and the related disclosures at the date of the financial statements, as well as the reported amounts of revenue and expenses during the periods presented. These estimates, judgments and assumptions take into account historical and forward-looking factors that the Company believes are reasonable including, but not limited to, the potential impacts arising from the COVID-19 pandemic and measures implemented to prevent its spread. As the extent and duration of the impacts from the COVID-19 pandemic remain unclear, the Company’s estimates and assumptions may evolve as conditions change. Significant items subject to such estimates, judgments and assumptions include revenue recognition, website and internal-use software development costs, goodwill, valuation and recoverability of intangible assets with finite lives and other long-lived assets, stock-based compensation, and income taxes. Actual results could differ significantly from these estimates.

Changes in Accounting Principle and Recently Issued Accounting Pronouncements

Changes in Accounting Principle

There have been no material changes to the Company’s significant accounting policies described in the 2020 Form 10-K.

Recently Issued Accounting Pronouncements

There were no recently issued accounting pronouncements that had or are expected to have a material impact on our financial statements.