Condensed Financial Information Disclosure [Abstract] Condensed Income Statement [Table] Condensed Income Statement [Table] Consolidation Items [Axis] Consolidation Items [Axis] Consolidation Items [Domain] Consolidation Items [Domain] Reportable Legal Entities Reportable Legal Entities [Member] Eliminations Consolidation, Eliminations [Member] Consolidated Entities [Axis] Consolidated Entities [Axis] Consolidated Entities [Domain] Consolidated Entities [Domain] Parent Parent Company [Member] Guarantor Subsidiaries Guarantor Subsidiaries [Member] Non-Guarantor Subsidiaries Non-Guarantor Subsidiaries [Member] Condensed Income Statements, Captions [Line Items] Condensed Income Statements, Captions [Line Items] Revenue Revenue from Contract with Customer, Including Assessed Tax Costs and expenses: Costs and Expenses [Abstract] Cost of revenue Cost of Revenue Selling and marketing Selling and Marketing Expense Technology and content Technology and Content Expense Technology and content expense includes product development and content expense, as well as information technology costs to support infrastructure, back-office applications and overall monitoring and security of networks, and is principally comprised of personnel and overhead, depreciation and amortization of technology assets including hardware, and purchased and internally developed software, and other costs including cloud expense, licensing and maintenance expense and stock-based compensation. General and administrative General and Administrative Expense Amortization of intangible assets Amortization of Intangible Assets Impairment of goodwill Goodwill, Impairment Loss Impairment of intangible assets Impairment of Intangible Assets (Excluding Goodwill) Legal reserves, occupancy tax and other Legal Reserves Occupancy Tax And Other Legal reserves, occupancy tax and other consists of changes in reserves for court decisions and the potential and final settlement of issues related to hotel occupancy taxes, expenses recognized related to monies paid in advance of occupancy and other tax proceedings as well as certain other legal reserves. Restructuring and related reorganization charges Restructuring Charges Intercompany (income) expense, net Intercompany Income Expense Net Intercompany income expense net Operating income Operating Income (Loss) Other income (expense): Nonoperating Income (Expense) [Abstract] Equity in pre-tax earnings of consolidated subsidiaries Income (Loss) from Subsidiaries, before Tax Other, net Condensed Consolidating Reporting Information, Other Income expense Net Condensed Consolidating Reporting Information - The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items. Total other expense, net Nonoperating Income (Expense) Income before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Provision for income taxes Income Tax Expense (Benefit) Net income Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Net income (loss) attributable to noncontrolling interests Net Income (Loss) Attributable to Noncontrolling Interest Net income attributable to Expedia, Inc. Net Income (Loss) Attributable to Parent Comprehensive income attributable to Expedia, Inc. Comprehensive Income (Loss), Net of Tax, Attributable to Parent Quarterly Financial Information Disclosure [Abstract] Operating income (loss) Basic (in dollars per share) Earnings Per Share, Basic Diluted (in dollars per share) Earnings Per Share, Diluted Schedule of Goodwill [Table] Schedule of Goodwill [Table] Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Nonrecurring Basis Fair Value, Measurements, Nonrecurring [Member] Segments [Axis] Segments [Axis] Segments [Domain] Segments [Domain] Reporting Unit Within Core Online Travel Companies [Member] Reporting Unit Within Core Online Travel Companies [Member] Reporting Unit Within Core Online Travel Companies [Member] Core OTA Core Online Travel Companies [Member] Core Online Travel Companies [Member] Goodwill [Line Items] Goodwill [Line Items] Segment Reporting [Abstract] Operating Segment Information Schedule of Segment Reporting Information, by Segment [Table Text Block] Schedule of Revenue by Services Revenue from External Customers by Products and Services [Table Text Block] Schedule of Revenue by Geographic Area Schedule of Revenue from External Customers Attributed to Foreign Countries by Geographic Area [Table Text Block] Schedule of Property and Equipment by Geographic Area Schedule of Disclosure on Geographic Areas, Long-Lived Assets in Individual Foreign Countries by Country [Table Text Block] Accounting Policies [Abstract] Organization and Basis of Presentation Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Goodwill and Intangible Assets Disclosure [Abstract] Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] 2018 Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months 2019 Finite-Lived Intangible Assets, Amortization Expense, Year Two 2020 Finite-Lived Intangible Assets, Amortization Expense, Year Three 2021 Finite-Lived Intangible Assets, Amortization Expense, Year Four 2022 Finite-Lived Intangible Assets, Amortization Expense, Year Five 2024 and thereafter Finite-Lived Intangible Assets, Amortization Expense, after Year Five Net Finite-Lived Intangible Assets, Net Income Statement [Abstract] Interest income Investment Income, Interest Interest expense Interest Expense Other, net Other Nonoperating Income (Expense) Income before income taxes Net income Net loss attributable to non-controlling interests Net income attributable to Expedia Group, Inc. Earnings per share attributable to Expedia Group, Inc. available to common stockholders: Earnings Per Share [Abstract] Shares used in computing earnings per share (000's): Weighted Average Number of Shares Outstanding, Diluted [Abstract] Basic (in shares) Weighted Average Number of Shares Outstanding, Basic Diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Restricted cash and cash equivalents Restricted Cash and Cash Equivalents Restricted cash included within long-term investments and other assets Restricted Cash and Cash Equivalents, Long-term Investments and Other Assets Restricted Cash and Cash Equivalents, Long-term Investments and Other Assets Total cash, cash equivalents and restricted cash and cash equivalents in the consolidated statement of cash flow Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Earnings Per Share Earnings Per Share [Text Block] Outstanding stock awards excluded from calculation of diluted earnings per share Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Income Tax Disclosure [Abstract] Income Taxes Income Tax Disclosure [Text Block] Equity [Abstract] Foreign currency translation adjustments, net of tax Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax Net unrealized gain (loss) on available for sale securities, net of tax Accumulated Other Comprehensive Income (Loss), Debt Securities, Available-for-sale, Adjustment, after Tax Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] 2.5% Senior Notes Due 2022 Two Point Five Percent Senior Notes Due On Two Zero Two Two [Member] Two Point Five Percent Senior Notes Due On Two Zero Two Two [Member] Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Foreign currency translation gains (losses), net of tax Cumulative Translation Adjustment for Net Investment Hedges, Net of Tax Cumulative Translation Adjustment for Net Investment Hedges, Net of Tax Foreign currency translation gains (losses), before tax Cumulative Translation Adjustment for Net Investment Hedge, Before Tax Cumulative translation adjustment in other comprehensive income reflecting gains or losses on foreign currency derivatives those are designated as, and are effective as, hedges of a net investment in a foreign entity, before tax effect. Senior notes, interest rate Debt Instrument, Interest Rate, Stated Percentage Net unrealized loss on available-for-sale-securities before tax Available-for-sale Securities, Accumulated Gross Unrealized Gain (Loss), before Tax Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Award Type [Axis] Award Type [Axis] Equity Award [Domain] Equity Award [Domain] Stock Options Employee Stock Option [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Risk-free interest rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Expected volatility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Expected life Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Dividend yield Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Weighted-average estimated fair value of options granted during the year Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Fair Value Disclosures [Abstract] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Investment, Name [Axis] Investment, Name [Axis] Investment, Name [Domain] Investment, Name [Domain] Despegar.com Corp. Despegar.com Corp. [Member] Despegar.com Corp. [Member] Investment Type [Axis] Investment Type [Axis] Investments [Domain] Investments [Domain] Available-for-sale Securities Available-for-sale Securities [Member] Recurring Basis Fair Value, Measurements, Recurring [Member] Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets, Major Class Name [Domain] Indefinite-lived Intangible Assets, Major Class Name [Domain] Trade Names Trade Names [Member] Derivative Instrument [Axis] Derivative Instrument [Axis] Derivative Contract [Domain] Derivative Contract [Domain] Foreign currency forward contracts Foreign Exchange Forward [Member] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Gain (Loss) on Investments Gain (Loss) on Investments Amortized cost Available-for-sale Securities, Amortized Cost Basis Accumulated gross unrealized loss Available-for-sale Equity Securities, Accumulated Gross Unrealized Loss, before Tax Notional amount of foreign currency derivatives Derivative, Notional Amount Foreign currency forward contracts, Assets Foreign Currency Derivative Instruments Not Designated as Hedging Instruments, Asset at Fair Value Net gains(losses) from foreign currency forward contracts Gain (Loss) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments Impairment of indefinite-lived intangible assets Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill) Finite-lived intangible assets, fair value disclosure Finite-lived Intangible Assets, Fair Value Disclosure Fair value of indefinite-lived intangible assets Indefinite-lived Intangible Assets (Excluding Goodwill), Fair Value Disclosure Loss on sale of cost method Investments Loss on Sale of Investments Investments without readily determinable fair values Equity Securities without Readily Determinable Fair Value, Amount Equity securities, gain (loss) Equity Securities, FV-NI, Gain (Loss) Equity securities, other-than-temporary impairments Equity Securities without Readily Determinable Fair Value, Impairment Loss, Annual Amount Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Seasonality Seasonality Policy [Policy Text Block] Seasonality Policy [Policy Text Block] Consolidation Consolidation, Policy [Policy Text Block] Accounting Estimates Use of Estimates, Policy [Policy Text Block] Reclassifications Reclassification, Policy [Policy Text Block] Revenue Recognition Revenue from Contract with Customer [Policy Text Block] Cash and Cash Equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Short-term and Long-term Investments Investment, Policy [Policy Text Block] Accounts Receivable Trade and Other Accounts Receivable, Policy [Policy Text Block] Property and Equipment Property, Plant and Equipment, Policy [Policy Text Block] Business Combinations Business Combinations Policy [Policy Text Block] Recoverability of Goodwill and Indefinite-Lived Intangible Assets Goodwill and Intangible Assets, Policy [Policy Text Block] Recoverability of Intangible Assets with Definite Lives and Other Long-Lived Assets Intangible Assets, Finite-Lived, Policy [Policy Text Block] Redeemable Noncontrolling Interests Redeemable Noncontrolling Interest [Policy Text Block] Disclosure of accounting policy for redeemable noncontrolling interest. Income Taxes Income Tax, Policy [Policy Text Block] Derivative Instruments Derivatives, Policy [Policy Text Block] Foreign Currency Translation and Transaction Gains and Losses Foreign Currency Transactions and Translations Policy [Policy Text Block] Debt Issuance Costs Debt, Policy [Policy Text Block] Marketing Promotions Marketing Promotions Policy [Policy Text Block] Marketing Promotions Policy [Policy Text Block] Stock-Based Compensation Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block] Earnings Per Share Earnings Per Share, Policy [Policy Text Block] Fair Value Recognition, Measurement and Disclosure Fair Value of Financial Instruments, Policy [Policy Text Block] Certain Risks and Concentrations Concentration Risk, Credit Risk, Policy [Policy Text Block] Contingent Liabilities Commitments and Contingencies, Policy [Policy Text Block] Occupancy Tax Occupancy Tax Policy [Policy Text Block] Occupancy Tax Policy [Policy Text Block] Recent Accounting Policies Not Yet Adopted New Accounting Pronouncements, Policy [Policy Text Block] Fair Value Measurements Fair Value Measurement, Policy [Policy Text Block] Property, Plant and Equipment [Abstract] Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Accounts Payable Accounts Payable [Member] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Build To Suit Asset Build To Suit Asset [Member] Build To Suit Asset [Member] New Corporate Headquarters New Corporate Headquarters [Member] New Corporate Headquarters [Member] Building Improvements Building Improvements [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Capitalized software development costs, net of accumulated amortization Capitalized Computer Software, Net Amortization of capitalized software development costs Capitalized Computer Software, Amortization Property and equipment, net Property, Plant and Equipment, Net Projects in progress Construction in Progress, Gross Capitalized construction cost Capitalized Build-To-Suit Assets Capitalized Build-To-Suit Assets Capital expenditures Payments to Acquire Property, Plant, and Equipment Acquisition of property and equipment, non-cash investing activity Construction in Progress Expenditures Incurred but Not yet Paid RSUs Restricted Stock Units (RSUs) [Member] RSUs Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Beginning balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Cancelled (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Ending balance (in shares) Weighted Average Grant-Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Beginning balance (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Granted (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Vested (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Cancelled (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Ending balance (in dollars per share) Noncontrolling Interest [Abstract] Redeemable Noncontrolling Interest, by Legal Entity [Table] Redeemable Noncontrolling Interest, by Legal Entity [Table] Trivago Trivago [Member] Trivago [Member] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] trivago Redeemable Noncontrolling Interest [Line Items] Redeemable Noncontrolling Interest [Line Items] Percentage of remaining minority ownership interest that may be acquired Percentage Of Remaining Minority Ownership Interest That May Be Acquired Percentage of remaining shares of minority interest that may be acquired during the open window. Percentage of remaining minority ownership interest to be acquired Percentage of Remaining Minority Ownership Interest to be Acquired Percentage of remaining shares of minority interest to be acquired. Proceeds related to trivago IPO, net of fees and expenses Stock Issued During Period, Value, Subsidiary Issuance Stock Issued During Period, Value, Subsidiary Issuance Ownership interest percentage Noncontrolling Interest, Ownership Percentage by Parent Voting interest percentage Noncontrolling Interest, Voting Interest of Parent Noncontrolling Interest, Voting Interest of Parent Reconciliation of Revenue from Segments to Consolidated [Table] Reconciliation of Revenue from Segments to Consolidated [Table] Contract with Customer, Sales Channel [Axis] Contract with Customer, Sales Channel [Axis] Contract with Customer, Sales Channel [Domain] Contract with Customer, Sales Channel [Domain] Sales Channel, Through Intermediary [Member] Sales Channel, Through Intermediary [Member] Customer [Axis] Customer [Axis] Customer [Domain] Customer [Domain] Merchant Merchant Customers [Member] Merchant Customers [Member] Agency Agency Customers [Member] Agency Customers [Member] Advertising and media Advertising and Media Customers [Member] Advertising and Media Customers [Member] HomeAway HomeAway Customers [Member] HomeAway Customers [Member] Product and Service [Axis] Product and Service [Axis] Product and Service [Domain] Product and Service [Domain] Lodging Lodging [Member] Lodging [Member] Air Air [Member] Air [Member] Other Other Services [Member] Other Services [Member] Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] United States UNITED STATES All other countries All Other Countries [Member] Balances and or activity atributable to all countries other than the United States. Segment Reporting, Revenue Reconciling Item [Line Items] Segment Reporting, Revenue Reconciling Item [Line Items] Condensed Balance Sheet Statement [Table] Condensed Balance Sheet Statement [Table] Condensed Balance Sheet Statements, Captions [Line Items] Condensed Balance Sheet Statements, Captions [Line Items] ASSETS Assets [Abstract] Total current assets Assets, Current Investment in subsidiaries Equity Method Investments Intangible assets, net Intangible Assets, Net (Excluding Goodwill) Goodwill Goodwill Other assets, net Other Assets TOTAL ASSETS Assets LIABILITIES AND STOCKHOLDERS’ EQUITY Liabilities and Equity [Abstract] Total current liabilities Liabilities, Current Long-term debt, excluding current maturities Long-term Debt, Excluding Current Maturities Other long-term liabilities Other Liabilities Redeemable non-controlling interests Redeemable Noncontrolling Interest, Equity, Carrying Amount Stockholders’ equity Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY Liabilities and Equity Intangible assets with indefinite lives Indefinite-lived Intangible Assets (Excluding Goodwill) Intangible assets with definite lives, net Goodwill and intangible assets Intangible Assets, Net (Including Goodwill) Commitments and Contingencies Disclosure [Abstract] Loss Contingencies [Table] Loss Contingencies [Table] Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] City of San Francisco Travel Companies [Member] Travel Companies [Member] Hawaii HAWAII Loss Contingency Nature [Axis] Loss Contingency Nature [Axis] Loss Contingency, Nature [Domain] Loss Contingency, Nature [Domain] Litigation relating to occupancy tax Litigation Relating to Occupancy Tax [Member] Litigation Relating to Occupancy Tax [Member] Litigation Related to Other Taxes Litigation Related to Other Taxes [Member] Litigation Related to Other Taxes [Member] Orbitz Worldwide, Inc. Orbitz Worldwide, Inc. [Member] Orbitz Worldwide, Inc. [Member] Loss Contingencies [Line Items] Loss Contingencies [Line Items] Number of lawsuits filed by cities, counties and states involving hotel occupancy taxes Loss Contingency Number Of Lawsuits This element represents the number of lawsuits in which the reporting entity was involved. Number of lawsuits currently active Loss Contingency Number Of Lawsuits Currently Active This element represents the number of lawsuits in which the reporting entity was involved and which are currently active. Number of lawsuits dismissed to date Loss Contingency, Claims Dismissed, Number Dismissal based in finding not subject to tax Dismissal Based On Finding Not Subject To Tax Dismissal findings. Reserve for legal contingencies Loss Contingency Accrual Pay-to-play occupancy and other tax payments Occupancy and Other Tax Assessment Payments Monies paid in advance of litigation in occupancy and other tax proceedings. Tax refunds received Proceeds from Tax Refund Proceeds from pay-to-play refund. Tax paid, net of refunds Taxes Paid, Net of Refunds Taxes Paid, Net of Refunds Payments for occupancy and other tax assessments Payments For Occupancy And Other Tax Assessment Paid To Date Payments in advances of litigation in occupancy and other tax proceedings, paid to date. Occupancy and other tax assessment refund received Occupancy and Other Tax Assessment Refund Received Occupancy and Other Tax Assessment Refund Received Occupancy and other tax assessment refund received, interest Occupancy and Other Tax Assessment Refund Received, Interest Occupancy and Other Tax Assessment Refund Received, Interest Deferred Tax Liabilities, Net [Abstract] Deferred Tax Liabilities, Net [Abstract] Deferred tax assets: Deferred Tax Assets, Net of Valuation Allowance [Abstract] Provision for accrued expenses Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Accrued Liabilities Deferred loyalty rewards Deferred Tax Assets, Loyalty Program Deferred Tax Assets, Loyalty Program Net operating loss and tax credit carryforwards Deferred Tax Assets Net Operating Loss And Tax Credit Carryforwards Deferred Tax Assets, Net Operating Loss And Tax Credit Carryforwards Stock-based compensation Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost Property and equipment Deferred Tax Assets, Property, Plant and Equipment Other Deferred Tax Assets, Other Total deferred tax assets Deferred Tax Assets, Gross Less valuation allowance Deferred Tax Assets, Valuation Allowance Net deferred tax assets Deferred Tax Assets, Net of Valuation Allowance Deferred tax liabilities: Deferred Tax Liabilities, Gross [Abstract] Goodwill and intangible assets Deferred Tax Liabilities, Intangible Assets Property and equipment Deferred Tax Liabilities, Property, Plant and Equipment Other Deferred Tax Liabilities, Other Total deferred tax liabilities Deferred Tax Liabilities, Gross Net deferred tax liability Deferred Tax Liabilities, Net Options Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Beginning balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures Exercised (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Cancelled (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period Ending balance (in shares) Exercisable as of December 31, 2018 (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Vested and expected to vest after December 31, 2018 (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Beginning balance (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Granted (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Exercised (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Cancelled (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Ending balance (in dollars per share) Exercisable as of December 31, 2018 (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Vested and expected to vest after December 31, 2018 (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] Remaining Contractual Life (In years), Balance as of December 31, 2018 Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Remaining Contractual Life (In years), Exercisable as of December 31, 2018 Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Remaining Contractual Life (In years), Vested and expected to vest after December 31, 2018 Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term Aggregate intrinsic value, Balance as of December 31, 2018 Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Aggregate intrinsic value, Exercisable as of December 31, 2018 Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Aggregate intrinsic value, Vested and expected to vest after December 31, 2018 Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value Restructuring and Related Activities [Abstract] Restructuring and Related Reorganization Charges Restructuring and Related Activities Disclosure [Text Block] Revenue, Initial Application Period Cumulative Effect Transition [Table] Revenue, Initial Application Period Cumulative Effect Transition [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] ASU 2014-09 Accounting Standards Update 2014-09 [Member] Initial Application Period Cumulative Effect Transition [Axis] Initial Application Period Cumulative Effect Transition [Axis] Initial Application Period Cumulative Effect Transition [Domain] Initial Application Period Cumulative Effect Transition [Domain] Calculated under Revenue Guidance in Effect before Topic 606 [Member] Calculated under Revenue Guidance in Effect before Topic 606 [Member] Difference between Revenue Guidance in Effect before and after Topic 606 [Member] Difference between Revenue Guidance in Effect before and after Topic 606 [Member] Revenue, Initial Application Period Cumulative Effect Transition [Line Items] Revenue, Initial Application Period Cumulative Effect Transition [Line Items] Current and long-term assets: Accounts receivable, net Accounts Receivable, Net Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Long-term investments and other assets Long-term Investments and Other Assets Long-term Investments and Other Assets Current and long-term liabilities: Liabilities [Abstract] Deferred merchant bookings Deferred Merchant Bookings Consists of amounts received from travelers who have not yet traveled. Accrued expenses and other current liabilities Accrued Liabilities and Other Liabilities Deferred income taxes Deferred Income Tax Liabilities, Net Stockholders' equity: Stockholders' Equity Attributable to Parent [Abstract] Retained earnings Retained Earnings (Accumulated Deficit) Goodwill and Intangible Assets, Net Goodwill and Intangible Assets Disclosure [Text Block] Statement of Comprehensive Income [Abstract] Other comprehensive income (loss), net of tax Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract] Currency translation adjustments, net of taxes Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax Unrealized losses on available for sale securities, net of taxes Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, after Tax Other comprehensive income (loss), net of tax Other Comprehensive Income (Loss), Net of Tax Comprehensive income Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Less: Comprehensive income (loss) attributable to non-controlling interests Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest Comprehensive income attributable to Expedia Group, Inc. Debt Disclosure [Abstract] Debt Debt Disclosure [Text Block] Related Party Transactions [Abstract] Related Party Transactions Related Party Transactions Disclosure [Text Block] Schedule Of Quarterly Financial Information Quarterly Financial Information [Table Text Block] Reconciliation of Redeemable Noncontrolling Interest Redeemable Noncontrolling Interest [Table Text Block] Statement of Stockholders' Equity [Abstract] Statement [Table] Statement [Table] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common stock Common Stock [Member] Additional paid-in capital Additional Paid-in Capital [Member] Treasury stock Treasury Stock [Member] Retained earnings (deficit) Retained Earnings [Member] Accumulated other comprehensive income (loss) AOCI Attributable to Parent [Member] Non-redeemable non-controlling interest Noncontrolling Interest [Member] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Class B Common Stock Common Class B [Member] Statement [Line Items] Statement [Line Items] Beginning Balance (in shares) Shares, Outstanding Beginning Balance Net income (excludes net income (loss) attributable to redeemable non-controlling interest) Net Income Excluding Portion Attributable To Redeemable Noncontrolling Interest Net Income Excluding Portion Attributable To Redeemable Noncontrolling Interest. Other comprehensive income (loss), net of taxes Other Comprehensive Income Loss Net Of Tax Excluding Portion Attributable To Noncontrolling Interest Other comprehensive income (loss) net of tax excluding portion attributable to non controlling interest, redeemable. Proceeds from exercise of equity instruments and employee stock purchase plans (in shares) Stock Issued During Period, Shares, New Issues Proceeds from exercise of equity instruments and employee stock purchase plans Stock Issued During Period, Value, New Issues Withholding taxes for stock options Adjustments Related to Tax Withholding for Share-based Compensation Issuance of common stock in connection with acquisitions (in shares) Stock Issued During Period, Shares, Acquisitions Issuance of common stock in connection with acquisitions Stock Issued During Period, Value, Acquisitions Treasury stock activity related to vesting of equity instruments (in shares) Treasury Stock Activity Related To Vesting Of Equity Instruments Shares Treasury stock activity related to vesting of equity instruments, shares Treasury stock activity related to vesting of equity instruments Treasury Stock Activity Related To Vesting Of Equity Instruments Treasury stock activity related to vesting of equity instruments Common stock repurchases (in shares) Treasury Stock, Shares, Acquired Common stock repurchases Treasury Stock, Value, Acquired, Cost Method Impact of adoption of new accounting guidance related to stock-based compensation Cumulative Effect of New Accounting Principle in Period of Adoption Proceeds from issuance of treasury stock (in shares) Stock Issued During Period, Shares, Treasury Stock Reissued Proceeds from issuance of treasury stock Stock Issued During Period, Value, Treasury Stock Reissued Payment of dividends to stockholders (declared at $1.00 per share) Dividends, Cash Adjustment to the fair value of redeemable non-controlling interests Noncontrolling Interest, Change in Redemption Value Change in ownership of non-controlling interest related to trivago initial public offering (IPO) Noncontrolling Interest, Increase from Subsidiary Equity Issuance Transfer from redeemable non-controlling interests Noncontrolling Interest, Transfer From Redeemable Noncontrolling interest Noncontrolling Interest, Transfer From Redeemable Noncontrolling interest Other changes in non-controlling interests Noncontrolling Interest, Period Increase (Decrease) Purchase of remaining interest in Air Asia Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests Stock-based compensation expense Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Other Stockholders' Equity, Other Ending Balance (in shares) Ending Balance Other Income and Expenses [Abstract] Other Income (Expense) Other Income and Other Expense Disclosure [Text Block] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Level 1 Fair Value, Inputs, Level 1 [Member] Level 2 Fair Value, Inputs, Level 2 [Member] Eligible Item or Group for Fair Value Option [Axis] Financial Instrument [Axis] Fair Value, Option, Eligible Item or Group [Domain] Financial Instruments [Domain] Money market funds Money Market Funds [Member] Time deposits Bank Time Deposits [Member] Marketable equity securities Equity Securities [Member] Cash equivalents Cash and Cash Equivalents, Fair Value Disclosure Investments Investments, Fair Value Disclosure Total assets Assets, Fair Value Disclosure Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] HomeAway Home Away Inc [Member] HomeAway,Inc. Egencia Egencia [Member] Egencia Operating Segments Operating Segments [Member] Corporate & Eliminations Corporate And Eliminations [Member] Corporate And Eliminations [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Intersegment revenue Intersegment Revenue Amount of revenue from transactions with other operating segments of the same entity. Adjusted EBITDA Adjusted Earnings Before Income Tax Depreciation Amortization Adjusted earnings before income tax, depreciation, and amortization, which is the primary operating metric for which our CODM manages our business. Depreciation Depreciation Amortization of intangible assets Impairment of goodwill Impairment of intangible assets Stock-based compensation Share-based Compensation Legal reserves, occupancy tax and other Restructuring and related reorganization charges Restructuring without Stock Based Compensation Restructuring and related reorganization charges without associated stock-based compensation, which is disclosed separately. Realized (gain) loss on revenue hedges Realized Gain Loss On Revenue Hedges Realized (gain) loss on revenue hedges. Other income (expense), net Net income attributable to Expedia Group, Inc. Domestic and Foreign Income (Loss) Before Income Taxes Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block] Components of Income Tax Expense Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Components of Deferred Tax Assets and Deferred Tax Liabilities Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Schedule of Statutory Federal Income Tax Rate to Income from Continuing Operations before Income Taxes Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Income Tax Reconciliation of Beginning and Ending Amount of Gross Unrecognized Tax Benefits Summary of Income Tax Contingencies [Table Text Block] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Customer relationships Customer Relationships [Member] Supplier relationships Supplier Relationships [Member] Supplier Relation Ships [Member] Technology Developed Technology Rights [Member] Domain names Domain Names [Member] Domain Names [Member] Other Other Intangible Assets [Member] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Cost Finite-Lived Intangible Assets, Gross Accumulated Amortization Finite-Lived Intangible Assets, Accumulated Amortization Redeemable Non-controlling Interests Noncontrolling Interest Disclosure [Text Block] Summary of Stock Option Activity Share-based Compensation, Stock Options, Activity [Table Text Block] Weighted Average Assumptions of Black-Scholes and Monte Carlo Option-Pricing Models Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Summary of Restricted Stock Units Activity Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block] Business Combinations [Abstract] Acquisitions and Other Investments Mergers, Acquisitions and Dispositions Disclosures [Text Block] U.S. Income (Loss) from Continuing Operations before Income Taxes, Domestic Foreign Income (Loss) from Continuing Operations before Income Taxes, Foreign Statement of Cash Flows [Abstract] Operating activities: Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract] Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation of property and equipment, including internal-use software and website development Amortization of stock-based compensation Amortization and impairment of intangible assets Amortization And Impairment Of Intangible Assets (Excluding Goodwill) Amortization And Impairment Of Intangible Assets (Excluding Goodwill) Deferred income taxes Deferred Income Tax Expense (Benefit) Foreign exchange (gain) loss on cash, restricted cash and short-term investments, net Foreign Exchange Gain Loss On Cash Cash Equivalents And Short Term Investments Net Foreign Exchange Gain Loss On Cash Cash Equivalents And Short Term Investments Net Realized (gain) loss on foreign currency forwards Gain (Loss) on Sale of Derivatives Loss on minority equity investments, net Other Other Noncash Income (Expense) Changes in operating assets and liabilities, net of effects from acquisitions: Increase (Decrease) in Operating Capital [Abstract] Accounts receivable Increase (Decrease) in Accounts Receivable Prepaid expenses and other assets Increase (Decrease) in Other Operating Assets Accounts payable, merchant Increase Decrease In Accounts Payable Merchant Increase (decrease) in accounts payable, merchant, which primarily consists of amounts billed from suppliers subsequent to the customers use of services. Accounts payable, other, accrued expenses and other current liabilities Increase (Decrease) in Other Accounts Payable and Accrued Liabilities Tax payable/receivable, net Increase (Decrease) in Income Taxes Deferred merchant bookings Increase Decrease In Deferred Merchant Bookings Increase (decrease) in deferred merchant bookings, which consists of amounts received from travelers who have not yet traveled. Deferred revenue Increase (Decrease) in Contract with Customer, Liability Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Investing activities: Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract] Capital expenditures, including internal-use software and website development Purchases of investments Payments to Acquire Investments Sales and maturities of investments Proceeds from Sale and Maturity of Other Investments Acquisitions, net of cash and restricted cash acquired Payments to Acquire Businesses, Net of Cash Acquired Other, net Payments for (Proceeds from) Other Investing Activities Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Financing activities: Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Payment of long-term debt Repayments of Long-term Debt Proceeds from issuance of long-term debt, net of issuance costs Proceeds from Debt, Net of Issuance Costs Payment of HomeAway Convertible Notes Payment Of Convertible Notes From Recently Acquired Subsidiary Cash outflow related to payment of Convertible Notes of a recently acquired company. Purchases of treasury stock Payments for Repurchase of Common Stock Proceeds from issuance of treasury stock Proceeds from Sale of Treasury Stock Payment of dividends to stockholders Payments of Ordinary Dividends Proceeds from exercise of equity awards and employee stock purchase plan Proceeds from Issuance or Sale of Equity Changes in controlled subsidiaries, net Increase (Decrease) in Controlled Subsidiaries Increase (Decrease) in Controlled Subsidiaries Other, net Proceeds from (Payments for) Other Financing Activities Net cash provided by (used in) financing activities Net Cash Provided by (Used in) Financing Activities Effect of exchange rate changes on cash, cash equivalents and restricted cash and cash equivalents Effect of Exchange Rate on Cash and Cash Equivalents Net increase (decrease) in cash, cash equivalents and restricted cash and cash equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Cash, cash equivalents and restricted cash and cash equivalents at beginning of year Cash, cash equivalents and restricted cash and cash equivalents at end of year Supplemental cash flow information Supplemental Cash Flow Information [Abstract] Cash paid for interest Interest Paid, Including Capitalized Interest, Operating and Investing Activities Income tax payments, net Income Taxes Paid, Net Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Cost of revenue Cost of Sales [Member] Selling and marketing Selling and Marketing Expense [Member] Technology and content Technology and Content Expense [Member] Technology and Content Expense [Member] General and administrative General and Administrative Expense [Member] Restructuring and related reorganization charges Restructuring Charges [Member] Stock-based compensation SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Table] SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Table] SEC Schedule, 12-09, Valuation Allowances and Reserves Type [Axis] SEC Schedule, 12-09, Valuation Allowances and Reserves Type [Axis] SEC Schedule, 12-09, Valuation Allowances and Reserves [Domain] SEC Schedule, 12-09, Valuation Allowances and Reserves [Domain] Allowance for doubtful accounts SEC Schedule, 12-09, Allowance, Credit Loss [Member] Other reserves Other Reserves [Member] Other Reserves [Member] SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items] SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items] Balance at Beginning of Period SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount Charges to Earnings SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Cost and Expense Charges to Other Accounts SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Other Account Deductions SEC Schedule, 12-09, Valuation Allowances and Reserves, Deduction Balance of End of Period Lease rental expense Operating Leases, Rent Expense Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] 2019 Operating Leases, Future Minimum Payments Due, Next Twelve Months 2020 Operating Leases, Future Minimum Payments, Due in Two Years 2021 Operating Leases, Future Minimum Payments, Due in Three Years 2022 Operating Leases, Future Minimum Payments, Due in Four Years 2023 Operating Leases, Future Minimum Payments, Due in Five Years 2024 and thereafter Operating Leases, Future Minimum Payments, Due Thereafter Total Operating Leases, Future Minimum Payments Due Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Maximum Maximum [Member] Minimum Minimum [Member] 7.456% Senior Notes Due 2018 Seven Point Four Five Six Percent Senior Notes Due On Two Zero One Eight [Member] Seven Point Four Five Six Percent Senior Notes Due On Two Zero One Eight 5.95% Senior Notes Due 2020 Five Point Nine Five Percent Senior Notes Due On Two Zero Two Zero [Member] Five Point Nine Five Percent Senior Notes Due On Two Zero Two Zero 4.5% Senior Notes Due 2024 Four Point Five Percent Senior Notes Due On Two Zero Two Four [Member] Four Point Five Percent Senior Notes Due On Two Zero Two Four [Member] 5.0% Senior Notes Due 2026 Five Point Zero Percent Senior Notes Due On Two Zero Two Six [Member] Five Point Zero Percent Senior Notes Due On Two Zero Two Six [Member] 3.8% Senior Notes Due 2028 Three Point Eight Percent Senior Notes Due On Two Zero Two Eight [Member] Three Point Eight Percent Senior Notes Due On Two Zero Two Eight [Member] Debt Instrument, Redemption, Period [Axis] Debt Instrument, Redemption, Period [Axis] Debt Instrument, Redemption, Period [Domain] Debt Instrument, Redemption, Period [Domain] Upon the occurrence of certain change of control triggering events Debt Instrument, Redemption, Period One [Member] Credit Facility [Axis] Credit Facility [Axis] Credit Facility [Domain] Credit Facility [Domain] Credit Facility Revolving Credit Facility [Member] Uncommitted Credit Facility Uncommitted Credit Facility [Member] Uncommitted Credit Facility Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Senior Notes Senior Notes [Member] International Subsidiary One Foreign Subsidiary One [Member] Foreign Subsidiary One [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Senior unsecured notes principal amount Debt Instrument, Face Amount Debt instrument redemption price percentage Debt Instrument, Redemption Price, Percentage Senior notes issued price percentage Senior Notes Issued Price Percentage The senior notes were issued at a percentage of par (less than 100% of par results in a discount). Accrued interest related to senior notes Interest Payable Credit facility Line of Credit Facility, Maximum Borrowing Capacity Commitment fee on undrawn amounts Line of Credit Facility, Unused Capacity, Commitment Fee Percentage Basis points added to LIBOR rate Debt Instrument, Basis Spread on Variable Rate Credit facility borrowings outstanding Long-term Line of Credit Letters of credit issued under the credit facility Letters of Credit Outstanding, Amount Schedule of Related Party Transactions, by Related Party [Table] Schedule of Related Party Transactions, by Related Party [Table] Related Party Transaction [Axis] Related Party Transaction [Axis] Related Party Transaction [Domain] Related Party Transaction [Domain] Reimbursement Agreement Reimbursement Agreement [Member] Reimbursement Agreement [Member] Airplane One Airplane One [Member] Airplane One [Member] Aircraft Flight Equipment [Member] Airplane Two Airplane Two [Member] Airplane Two [Member] Related Party [Axis] Related Party [Axis] Related Party [Domain] Related Party [Domain] Liberty Liberty [Member] Liberty [Member] Expedia, Inc Expedia, Inc [Member] Expedia, Inc [Member] Iac Iac [Member] IAC Related Party Related Party [Member] Related Party [Member] Related Party Transaction [Line Items] Related Party Transaction [Line Items] Proceeds from reimbursement of expenses Related Party Transaction, Proceeds From Reimbursement of Expenses Incurred Related Party Transaction, Proceeds From Reimbursement of Expenses Incurred Common stock issued from treasury stock Treasury stock reissued, price per share Stock Issued During Period Treasury Stock Reissued Average Cost Per Share Total cost of shares issued divided by the total number of shares issued. Stock issued, aggregate value Airplane ownership interest Airplane Ownership Interest Airplane Ownership Interest Ownership interest of airplanes Ownership Interest In Plane Net basis in our ownership interest in the plane recorded in long-term investments and other assets Number of reportable segments Number of Reportable Segments Defined Contribution Plan [Abstract] Percentage of employees contributions maximum Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent Percentage of company matches of employees contributions maximum Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay Employee vesting period Defined Contribution Plan, Employers Matching Contribution, Vesting Period Defined Contribution Plan, Employers Matching Contribution, Vesting Period Employer contributions for benefit plans Defined Contribution Plan, Employer Discretionary Contribution Amount Schedule of Commitments and Obligations Contractual Obligation, Fiscal Year Maturity Schedule [Table Text Block] Estimated Future Minimum Rental Payments Under Operating Leases Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Total Long-term Debt Current maturities of long-term debt Long-term Debt, Current Maturities Condensed Cash Flow Statement [Table] Condensed Cash Flow Statement [Table] Condensed Cash Flow Statements, Captions [Line Items] Condensed Cash Flow Statements, Captions [Line Items] Net cash provided by operating activities Transfers (to) from related parties Transfers To From Related Parties In Investing Activities Transfers to from related parties in investing activities. Other Investing Activities Net Other Investing Activities Net Other Investing Activities Net Transfers (to) from related parties Transfers To From Related Parties Transfers to from related parties Other, net Other Financing Activities Net Other Financing Activities Net Proceeds from issuance of long-term debt, net of debt issuance costs Proceeds from Issuance of Long-term Debt, Net of Issuance Costs Proceeds from Issuance of Long-term Debt, Net of Issuance Costs Income Taxes [Table] Income Taxes [Table] Income Taxes [Table] Income Tax Authority, Name [Axis] Income Tax Authority, Name [Axis] Income Tax Authority, Name [Domain] Income Tax Authority, Name [Domain] IRS Internal Revenue Service (IRS) [Member] Income Tax Authority [Axis] Income Tax Authority [Axis] Income Tax Authority [Domain] Income Tax Authority [Domain] Federal Domestic Tax Authority [Member] State State and Local Jurisdiction [Member] Foreign Foreign Tax Authority [Member] Income Taxes [Line Items] Income Taxes [Line Items] Income Taxes [Line Items] Provisional transition tax obligation for repatriation of foreign earnings Effective Income Tax Rate Reconciliation, Tax Cuts and Jobs Act of 2017, Transition Tax on Accumulated Foreign Earnings, Amount Effective Income Tax Rate Reconciliation, Tax Cuts and Jobs Act of 2017, Transition Tax on Accumulated Foreign Earnings, Amount Reduction in current income tax payable attributable to stock-based compensation Current Income Tax Benefit Associated With Stock Based Awards Current Income Tax Benefit Associated With Stock Based Awards. Net operating loss carryforwards Operating Loss Carryforwards Indefinite foreign net operating loss carryforwards Operating Loss Carryforwards Indefinitely Operating Loss Carryforwards Indefinitely Foreign net operating loss carryforwards subject to expiration Operating Loss Carry forwards Expiring At Various Periods Operating Loss Carry forwards Expiring At Various periods Valuation allowance Increase (decrease) in NOL valuation allowance Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount Undistributed earnings of foreign subsidiaries Undistributed Earnings of Foreign Subsidiaries Unrecognized deferred tax liability related to the U.S. federal income tax consequences of undistributed earnings of foreign subsidiaries Deferred Tax Liability Not Recognized, Amount of Unrecognized Deferred Tax Liability, Undistributed Earnings of Foreign Subsidiaries Effective interest rate of federal statutory income tax rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Unrecognized tax benefits Unrecognized Tax Benefits Unrecognized tax benefits that would impact effective tax rate Unrecognized Tax Benefits that Would Impact Effective Tax Rate Uncertain tax positions, interest and penalties Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued Interest and penalties Unrecognized Tax Benefits Income Tax Penalties And Interest Expense (Benefit) Unrecognized Tax Benefits Income Tax Penalties And Interest Expense (Benefit) Increase in prior years taxable revenue due to tax examination Income Tax Examination, Increase (Decrease) in Prior Year Taxable Income Income Tax Examination, Increase (Decrease) in Prior Year Taxable Income Additional federal tax expense due to tax examination Income Tax Examination, Estimate of Possible Loss Dividends Payable [Table] Dividends Payable [Table] Dividends [Axis] Dividends [Axis] Dividends [Domain] Dividends [Domain] February 7, 2018 Declaration Date One [Member] February 4, 2015 April 24, 2018 Declaration Date Two [Member] February 5, 2014 July 23, 2018 Declaration Date Three [Member] Declaration Date Three [Member] October 19, 2018 Declaration Date Four [Member] Declaration Date Four [Member] February 7, 2017 Declaration Date Five [Member] Declaration Date Five [Member] April 26, 2017 Declaration Date Six [Member] Declaration Date Six [Member] July 26, 2017 Declaration Date Seven [Member] Declaration Date Seven [Member] October 25, 2017 Declaration Date Eight [Member] Declaration Date Eight [Member] February 8, 2016 Declaration Date Nine [Member] Declaration Date Nine [Member] April 26, 2016 Declaration Date Ten [Member] Declaration Date Ten [Member] July 27, 2016 Declaration Date Eleven [Member] Declaration Date Eleven [Member] October 24, 2016 Declaration Date Twelve [Member] Declaration Date Twelve [Member] Dividends Payable [Line Items] Dividends Payable [Line Items] Dividend Per Share Common Stock, Dividends, Per Share, Cash Paid Payment of dividends to stockholders Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Travel Related Companies Travel Related Companies [Member] Travel Related Companies [Member] Traveloka Holding Limited Traveloka Holding Limited [Member] Traveloka Holding Limited [Member] Business Acquisition [Line Items] Business Acquisition [Line Items] Weighted average life of acquired intangible assets Acquired Finite-lived Intangible Assets, Weighted Average Useful Life Business acquisition, cash acquired Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents Equity method investment, non-cash consideration Business Combination, Step Acquisition, Equity Interest in Acquiree, Fair Value Business acquisitions, equity interest Business Combination, Consideration Transferred, Equity Interests Issued and Issuable Deductible for tax purposes Business Acquisition, Goodwill, Expected Tax Deductible Amount Statement of Financial Position [Abstract] Accounts receivable, allowance Allowance for Doubtful Accounts Receivable, Current Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Common stock, Shares authorized Common Stock, Shares Authorized Common stock, Shares issued Common Stock, Shares, Issued Common stock, Shares outstanding Common Stock, Shares, Outstanding Treasury stock - Common stock, Shares Treasury Stock, Shares Organization, Consolidation and Presentation of Financial Statements [Abstract] Guarantor and Non-Guarantor Supplemental Financial Information Condensed Financial Statements [Text Block] Significant Accounting Policies Significant Accounting Policies [Text Block] Goodwill, Beginning Balance Additions Goodwill, Acquired During Period Foreign exchange translation and other Goodwill, Foreign Currency Translation Gain (Loss) Foreign exchange translation and other Goodwill, Foreign Currency Translation Gain (Loss) and Other Gain (Loss) Goodwill, Foreign Currency Translation Gain (Loss) and Other Gain (Loss) Goodwill, Ending Balance Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Long Term Debt Outstanding Schedule of Long-term Debt Instruments [Table Text Block] Components of Other Income (Expense) Schedule of Other Nonoperating Income (Expense) [Table Text Block] Segment Information Segment Reporting Disclosure [Text Block] Number of shares repurchased Average price per share (in dollars per share) Treasury Stock Acquired, Average Cost Per Share Total cost of repurchases Treasury Stock, Value, Acquired, Cost Method, Net Of Transaction Costs Treasury Stock, Value, Acquired, Cost Method, Net Of Transaction Costs Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event Subsequent Event [Member] Class of Stock [Line Items] Class of Stock [Line Items] Common stock, shares authorized Number of voting rights to each shareholder, per share Number Of Voting Rights To Each Preferred Shareholder Number Of Voting Rights To Each Preferred Shareholder Total number of directors elected by holders of common stock, voting as single class, percentage Number Of Directors Elected By Holders Of Common Stock Voting As Single Class Percentage Total Number Of Directors Elected By Holders Of Common Stock, Voting As Single Class, Percentage Preferred stock outstanding Preferred Stock, Shares Outstanding Authorized share repurchase Stock Repurchase Program, Number of Shares Authorized to be Repurchased Shares authorized and remaining under the repurchase program Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased Cost of stock repurchases Fair Value Measurements Fair Value Measurement and Measurement Inputs, Recurring and Nonrecurring [Text Block] Noncontrolling Interest [Table] Noncontrolling Interest [Table] Air Asia AirAsia [Member] AirAsia [Member] Air Asia Expedia Air Asia Expedia [Member] Air Asia Expedia [Member] Investment Group Investment Group [Member] Investment Group [Member] Noncontrolling Interest [Line Items] Noncontrolling Interest [Line Items] Equity interests held prior to acquisition Business Combination, Step Acquisition, Equity Interest in Acquiree, Percentage Cash consideration Payments to Acquire Interest in Subsidiaries and Affiliates Net decrease in Expedia Group, Inc.’s paid-in capital related to trivago IPO Other Noncontrolling Interest, Other Increase (Decrease) Noncontrolling Interest, Other Increase (Decrease) Net transfers from non-controlling interest Change from net income attributable to Expedia Group, Inc. and transfers from non-controlling interest Changes from net income attributable to Parent and transfers from (to) noncontrolling interests Changes from net income attributable to Parent and transfers (to) from noncontrolling interests Restructuring reserve Restructuring Reserve Stock-Based Awards and Other Equity Instruments Disclosure of Share-based Compensation Arrangements by Share-based Payment Award [Table Text Block] Summary of Changes in Valuation and Qualifying Accounts Valuation And Qualifying Accounts [Table Text Block] Valuation And Qualifying Accounts [Table Text Block] Accumulated goodwill impairment loss Goodwill, Impaired, Accumulated Impairment Loss Property and Equipment, Net Property, Plant and Equipment Disclosure [Text Block] Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward] Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward] Beginning balance Acquisition of redeemable non-controlling interest Noncontrolling Interest, Increase from Business Combination Purchase of subsidiary shares at fair value Redeemable Noncontrolling Interest, Decrease from Redemptions Decrease in redeemable noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests). Net income (loss) attributable to non-controlling interests Net Income (Loss) Attributable to Redeemable Noncontrolling Interest Fair value adjustments Noncontrolling Interest, Change in Redemption Value Allocated to Equity and Income Change in noncontrolling interest during the period as a result of a change in the redemption value of redeemable noncontrolling interest, including amounts recorded to stockholders equity as well as the income statement. Currency translation adjustments Currency Translation Adjustments And Other Attributable To Noncontrolling Interest Amount of currency translation and other items attributable to noncontrolling interests. Other Redeemable Noncontrolling Interest, Equity, Other Increase (Decrease) Redeemable Noncontrolling Interest, Equity, Other Increase (Decrease) Transfer to non-redeemable non-controlling interest Noncontrolling Interest, Decrease from Transfer to Non-redeemable Noncontrolling Interest Noncontrolling Interest, Decrease from Transfer to Non-redeemable Noncontrolling Interest Ending balance Schedule of Purchase Price Allocation Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block] Schedule of Cash and Cash Equivalents [Table Text Block] Schedule of Cash and Cash Equivalents [Table Text Block] Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block] Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block] Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract] Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract] Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract] Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract] Intangible assets with definite lives Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles Net assets and non-controlling interests acquired Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities [Abstract] Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities [Abstract] Deferred tax liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Total Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net Quarterly Financial Information (Unaudited) Quarterly Financial Information [Text Block] Net loss attributable to redeemable noncontrolling interest Dividends declared per common share (in dollars per share) Common Stock, Dividends, Per Share, Declared Document And Entity Information [Abstract] Document and Entity Information Abstract Document Information [Table] Document Information [Table] Document Information [Line Items] Document Information [Line Items] Document Type Document Type Amendment Flag Amendment Flag Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Trading Symbol Trading Symbol Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Entity Current Reporting Status Entity Current Reporting Status Entity Voluntary Filers Entity Voluntary Filers Entity Emerging Growth Company Entity Emerging Growth Company Entity Smaller Reporting Company Entity Small Business Entity Shell Company Entity Shell Company Entity Filer Category Entity Filer Category Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Entity Public Float Entity Public Float Weighted average number of shares outstanding (000's): Weighted Average Number of Shares Outstanding Reconciliation [Abstract] Dilutive effect of: Incremental Weighted Average Shares Attributable to Dilutive Effect [Abstract] Options to purchase common stock Incremental Common Shares Attributable To Call Options Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of call options using the treasury stock method. Other dilutive securities Incremental Common Shares Attributable To Other Dilutive Securities Incremental Common Shares Attributable to Other Dilutive Securities Schedule of Statement of Operations Information Condensed Income Statement [Table Text Block] Schedule of Balance Sheet Information Condensed Balance Sheet [Table Text Block] Schedule of Cash Flow Statement Information Condensed Cash Flow Statement [Table Text Block] Postemployment Benefits [Abstract] Employee Benefit Plans Compensation and Employee Benefit Plans, Other than Share-based Compensation [Text Block] Share Repurchases Class of Treasury Stock [Table Text Block] Summary Of Dividends Declared Dividends Declared [Table Text Block] Accumulated Other Comprehensive Loss , Net of Taxes Comprehensive Income (Loss) [Table Text Block] Effects of Changes in Ownership Interest on Stockholders Equity Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Table Text Block] Capitalized software development Software Development [Member] Computer equipment Computer Equipment [Member] Furniture and other equipment Furniture and Other Equipment [Member] Furniture and Other Equipment [Member] Buildings and leasehold improvements Buildings and Leasehold Improvements [Member] Buildings and Leasehold Improvements [Member] Land Land [Member] Total property and equipment, gross Property, Plant and Equipment, Gross Less: accumulated depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Property and equipment, net Current income tax expense: Components of Income Tax Expense (Benefit), Continuing Operations [Abstract] Federal Current Federal Tax Expense (Benefit) State Current State and Local Tax Expense (Benefit) Foreign Current Foreign Tax Expense (Benefit) Current income tax expense Current Income Tax Expense (Benefit) Deferred income tax (benefit) expense: Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract] Federal Deferred Federal Income Tax Expense (Benefit) State Deferred State and Local Income Tax Expense (Benefit) Foreign Deferred Foreign Income Tax Expense (Benefit) Deferred income tax (benefit) expense: Income tax expense Financial Assets and Liabilities Measured at Fair Value on Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Schedule of Goodwill and Intangible Assets Schedule of Intangible Assets and Goodwill [Table Text Block] Changes in Goodwill by Reportable Segment Schedule of Goodwill [Table Text Block] Components of Intangible Assets with Definite Lives Schedule of Finite-Lived Intangible Assets [Table Text Block] Estimated Future Amortization Expense Related to Intangible Assets Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Current assets: Assets, Current [Abstract] Restricted cash and cash equivalents Restricted Cash and Cash Equivalents, Current Short-term investments Short-term Investments Accounts receivable, net of allowance of $34 and $31 Accounts Receivable, Net, Current Income taxes receivable Income Taxes Receivable, Current Total current assets Long-term investments and other assets Investments and Other Noncurrent Assets Deferred income taxes Deferred Income Tax Assets, Net Current liabilities: Liabilities, Current [Abstract] Accounts payable, merchant Accounts Payable Merchant Consists primarily of amounts billed from suppliers subsequent to the customers use of services. Accounts payable, other Accounts Payable, Other, Current Deferred revenue Contract with Customer, Liability, Current Income taxes payable Accrued Income Taxes, Current Accrued expenses and other current liabilities Accrued Liabilities, Current Current maturities of long-term debt Total current liabilities Other long-term liabilities Other Liabilities, Noncurrent Commitments and contingencies Commitments and Contingencies Stockholders’ equity: Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Common stock Common Stock, Value, Issued Additional paid-in capital Additional Paid in Capital, Common Stock Treasury stock — Common stock, at cost Shares: 89,258 and 87,077 Treasury Stock, Value Accumulated other comprehensive income (loss) Total Expedia Group, Inc. stockholders’ equity Stockholders' Equity Attributable to Parent Non-redeemable non-controlling interests Nonredeemable Noncontrolling Interest Total stockholders’ equity Significant Accounting Policies [Table] Significant Accounting Policies [Table] Significant Accounting Policies [Table] Contract with Customer, Basis of Pricing [Axis] Contract with Customer, Basis of Pricing [Axis] Contract with Customer, Basis of Pricing [Domain] Contract with Customer, Basis of Pricing [Domain] Deferred Merchant Bookings Deferred Merchant Bookings [Member] Deferred Merchant Bookings [Member] Deferred Loyalty Rewards Deferred Loyalty Rewards [Member] Deferred Loyalty Rewards [Member] Other Deferred Revenue Other Deferred Revenue [Member] Other Deferred Revenue [Member] ASU 2016-01 Accounting Standards Update 2016-01 [Member] ASU 2016-16 Accounting Standards Update 2016-16 [Member] ASU 2018-02 Accounting Standards Update 2018-02 [Member] Accounting Standards Update 2018-02 [Member] ASU 2016-02 Accounting Standards Update 2016-02 [Member] Software Development Scenario [Axis] Scenario [Axis] Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Forecast Scenario, Forecast [Member] Significant Accounting Policies [Line Items] Significant Accounting Policies [Line Items] Significant Accounting Policies [Line Items] Deferred merchant bookings liability, current Deferred Merchant Bookings Liability, Current Deferred Merchant Bookings Liability, Current Deferred merchant booking liability, decrease due to recognition during period Deferred Merchant Booking Liability, Decrease Due to Recognition During Period Deferred Merchant Booking Liability, Decrease Due to Recognition During Period Contract with customer, liability, revenue recognized Contract with Customer, Liability, Revenue Recognized Customer loyalty program, period of recognition Customer Loyalty Program, Period of Recognition Customer Loyalty Program, Period of Recognition Property and equipment, estimated useful lives Property, Plant and Equipment, Useful Life Definite lived intangible assets, estimated useful life Finite-Lived Intangible Asset, Useful Life Vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Effect on retained earnings before tax impact Retained Earnings (Accumulated Deficit) Before Taxes Retained Earnings (Accumulated Deficit) Before Taxes Effect on retained earnings Effect on AOCI Effect on loyalty program before tax impact Increase (Decrease) in Contract With Customer, Loyalty Program Liability, Before Taxes Increase (Decrease) in Contract With Customer, Loyalty Program Liability, Before Taxes Effect on loyalty program Increase (Decrease) in Contract With Customer, Loyalty Program Liability Increase (Decrease) in Contract With Customer, Loyalty Program Liability Immaterial adjustments before tax impact New Accounting Pronouncement or Change in Accounting Principle, Other Adjustments, Before Taxes New Accounting Pronouncement or Change in Accounting Principle, Other Adjustments, Before Taxes Immaterial adjustments New Accounting Pronouncement or Change in Accounting Principle, Other Adjustments New Accounting Pronouncement or Change in Accounting Principle, Other Adjustments Effect on variable consideration before tax impact Revenue from Contract with Customer, Excluding Assessed Tax Effect on variable consideration Revenue from Contract with Customer, Excluding Assessed Tax, Net of Taxes Revenue from Contract with Customer, Excluding Assessed Tax, Net of Taxes Deferred tax assets, net Deferred Tax Assets, Net Tax cuts and jobs act, reclassification from AOCI to retained earnings, tax effect Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect Operating lease, right-of-use asset Operating Lease, Right-of-Use Asset Operating lease, right-of-use asset, gross Operating Lease, Right-of-Use Asset, Gross Operating Lease, Right-of-Use Asset, Gross Existing lease incentives and deferred rent Incentive To Lessee And Deferred Rent Incentive To Lessee And Deferred Rent Operating lease, liability Operating Lease, Liability Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Beginning balance Increases to tax positions related to the current year Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions Increases to tax positions related to prior years Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions Decreases to tax positions related to prior years Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions Reductions due to lapsed statute of limitations Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations Settlements during current year Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities Interest and penalties Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense Ending balance Components of Property and Equipment, Net Property, Plant and Equipment [Table Text Block] Reconciliation of Assets from Segment to Consolidated [Table] Reconciliation of Assets from Segment to Consolidated [Table] Segment Reporting, Asset Reconciling Item [Line Items] Segment Reporting, Asset Reconciling Item [Line Items] Fair value of senior notes Debt Instrument, Fair Value Disclosure Basic and Diluted Earnings Per Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Stockholders' Equity Stockholders' Equity Note Disclosure [Text Block] Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table] Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table] Title of Individual [Axis] Title of Individual [Axis] Relationship to Entity [Domain] Relationship to Entity [Domain] Former Chief Executive Officer Former Chief Executive Officer [Member] Former Chief Executive Officer [Member] Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] Employee Stock Purchase Plan 2013 Employee Stock Purchase Plan Twenty Thirteen [Member] Employee Stock Purchase Plan Twenty Thirteen [Member] Common stock reserved for new stock-based awards, shares Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Stock price, as of year end (in dollars per share) Share Price Total intrinsic value of stock options exercised, value Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Stock options granted during the period Incremental stock based expense due to call of options previously exercised Incremental Stock Based Compensation Charge Incremental Stock Based Compensation Charge Stock-based compensation Allocated Share-based Compensation Expense Stock-based compensation recovered due to forfeiture of awards Share-based Compensation Expense, Forfeiture of Stock Options Share-based Compensation Expense, Forfeiture of Stock Options Market value of shares vested in period Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value Stock-based compensation tax benefit Employee Service Share-based Compensation, Tax Benefit from Compensation Expense Cash received from stock-based award exercises Proceeds from Stock Options Exercised Income tax benefit associated with employees exercise of stock-based awards Weighted average exercise price of shares issued (in dollars per share) Unrecognized stock-based compensation expense Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Unrecognized stock-based compensation expense expected recognition period Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Common stock purchase price as percentage of fair market value Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent Eligible employees contribution of base compensation Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate Employee stock purchase plan, shares purchased Stock Issued During Period, Shares, Employee Stock Purchase Plans Employee stock ownership plan, average purchase price of shares purchased Share-based Compensation Arrangement by Share-based Payment Award, Per Share Weighted Average Price of Shares Purchased Shares of our common stock reserved for issuance Common Stock, Capital Shares Reserved for Future Issuance Foreign exchange rate gains (losses), net Foreign Currency Transaction Gain (Loss), before Tax Losses on minority equity investments, net Other Other Non Operating Income Expense Other Net Other Non Operating Income Expense Other Net Total Letters Of Credit Standby Letters of Credit [Member] Purchase obligations Purchase Obligation, Fiscal Year Maturity [Abstract] Total Purchase Obligation Less than 1 year Purchase Obligation, Due in Next Twelve Months 1 to 3 years Purchase Obligation, Due in Second and Third Year 3 to 5 years Purchase Obligation, Due in Fourth and Fifth Year More than 5 years Purchase Obligation, Due after Fifth Year Guarantees Guarantees [Abstract] Total Guarantees Guarantees Less than 1 year Guarantees, Due in Next Twelve Months Guarantees, Due in Next Twelve Months 1 to 3 years Guarantees, Due in Second and Third Year Guarantees, Due in Second and Third Year 3 to 5 years Guarantees, Due in Fourth and Fifth year Guarantees, Due in Fourth and Fifth year More than 5 years Guarantees, Due After Fifth Year Guarantees, Due After Fifth Year Letters of credit Long-term Debt, Fiscal Year Maturity [Abstract] Total Contractual Obligation Less than 1 year Contractual Obligation, Due in Next Fiscal Year 1 to 3 years Contractual Obligation, Due in Second and Third Year 3 to 5 years Contractual Obligation, Due in Fourth and Fifth Year More than 5 years Contractual Obligation, Due after Fifth Year Total Commitments And Obligations Total commitments and obligations Less than 1 year Commitments And Obligations, Due in Next Twelve Months Commitments and obligations less than one year 1 to 3 years Commitments And Obligations, Due in Second and Third Year Commitments and obligations between one to three years 3 to 5 years Commitments And Obligations, Due in Fourth and Fifth Year Commitments And Obligations Between Three to Five Years More than 5 years Commitments And Obligations, Due After Fifth Year Commitments And Obligations More Than Five Years Income tax expense at the federal statutory rate of 21% for 2018 and 35% for 2017 and 2016 Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount Foreign tax rate differential Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Amount Federal research and development credit Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount Excess tax benefits related to stock-based compensation Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Amount Unrecognized tax benefits and related interest Effective Income Tax Rate Reconciliation, Tax Contingency, Amount Change in valuation allowance Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount Return to provision true-ups Effective Income Tax Rate Reconciliation, Return to Provision, Amount Effective Income Tax Rate Reconciliation, Return to Provision, Amount trivago stock-based compensation Effective Income Tax Rate Reconciliation, Nondeductible Expense, Acquisition, Share-based Compensation Cost, Amount Effective Income Tax Rate Reconciliation, Nondeductible Expense, Acquisition, Share-based Compensation Cost, Amount State taxes Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount Non-deductible goodwill impairment Effective Income Tax Rate Reconciliation, Nondeductible Expense, Impairment Losses, Amount Tax Act transition tax U.S. statutory tax rate change Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount Global intangible low-taxed income Effective Income Tax Rate Reconciliation,Tax Cuts and Jobs Act of 2017, Global Intangible Low-Taxed Income, Amount Effective Income Tax Rate Reconciliation,Tax Cuts and Jobs Act of 2017, Global Intangible Low-Taxed Income, Amount Foreign-derived intangible income Effective Income Tax Rate Reconciliation, Deduction, Amount Other, net Effective Income Tax Rate Reconciliation, Other Reconciling Items, Amount Valuation and Qualifying Accounts SEC Schedule, 12-09, Schedule of Valuation and Qualifying Accounts Disclosure [Text Block]