Accounts Payable And Accrued Liabilities Current Accounts payable and accrued expenses Accounts Receivable Net Current Accounts receivable, net Accumulated Other Comprehensive Income Loss Net Of Tax Accumulated other comprehensive loss Additional Paid In Capital Additional paid-in capital Adjustments To Reconcile Net Income Loss To Cash Provided By Used In Operating Activities [Abstract] Adjustments to reconcile net income to net cash provided by operating activities: Aggregate amount for legal actions for which no loss amount has been accrued. Aggregate Amount For Legal Actions For Which No Loss Amount Has Been Accrued Aggregate amount for legal actions for which no loss amount has been accrued Allocation of net income available to common shareholders using the two-class method. Allocation Of Net Income Available To Common Shareholders Using Two Class Method Table [Text Block] Allocation of Net Income Available to Common Shareholders using Two-Class Method Amendment Flag Amendment Flag Amortization Of Financing Costs And Discounts Accrued interest Amortization Of Intangible Assets Total aggregate amortization expense for intangible assets Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount Anti-dilutive shares A R Argentina [Member] Asset Backed Securities [Member] Asset Backed Securities [Member] Assets Assets Total assets Assets [Abstract] Assets Assets Current Total current assets Assets Current [Abstract] Current assets: Assets liabilities and net assets of company's subsidiaries. Assets Liabilities And Net Assets Of Companys Subsidiaries Table [Text Block] Assets, Liabilities and Net Assets of Company's Venezuelan Subsidiaries Assets Liabilities And Net Assets Of Subsidiaries [Line Items] Assets Liabilities And Net Assets Of Subsidiaries [Line Items] Assets Liabilities And Net Assets Of Subsidiaries [Line Items] Assets Liabilities And Net Assets Of Subsidiaries [Table] Assets Liabilities And Net Assets Of Subsidiaries [Table] Assets Liabilities And Net Assets Of Subsidiaries [Table] Assets Net Net Assets Assets Noncurrent Total non-current assets Assets Noncurrent [Abstract] Non-current assets: Auction Rate Securities [Member] Auction Rate Securities [Member] Available For Sale Securities Amortized Cost Gross Amortized Cost Available for sale securities debt maturities fair value. Available For Sale Securities Debt Maturities Fair Value Table [Text Block] Estimated Fair Value of Short-Term and Long-Term Investments Available for sale securities debt maturities four to five years fair value. Available For Sale Securities Debt Maturities Four To Five Years Fair Value Four years to five years Available for sale securities debt maturities more than five years fair value Available For Sale Securities Debt Maturities More Than Five Years Fair Value More than five years Available for sale securities debt maturities one to two years fair value. Available For Sale Securities Debt Maturities One To Two Years Fair Value One year to two years Available for sale securities debt maturities three to four years fair value. Available For Sale Securities Debt Maturities Three To Four Years Fair Value Three years to four years Available for sale securities debt maturities two to three years fair value. Available For Sale Securities Debt Maturities Two To Three Years Fair Value Two years to three years Available For Sale Securities Debt Maturities Within One Year Fair Value One year or less Available For Sale Securities Debt Securities Estimated Fair Value Availableforsale Securities Gross Unrealized Gain Gross Unrealized Gains Available For Sale Securities Gross Unrealized Losses 1 Gross Unrealized Losses Available For Sale Securities [Text Block] Fair Value of Short and Long-Term Investments Classified as Available for Sale Securities Average closing stock price. Average Closing Stock Price Average closing stock price Basis Of Accounting Policy Policy [Text Block] Basis of presentation B R Brazil [Member] Brazilian Federal Tax Claims [Member] Brazilian Federal Tax Claims [Member] Brazilian Federal Tax Claims [Member] Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] Cash And Cash Equivalents At Carrying Value Cash and cash equivalents, end of the period Cash and cash equivalents, beginning of the period Cash and cash equivalents Cash And Cash Equivalents Fair Value Disclosure Cash and Cash Equivalents Cash And Cash Equivalents Period Increase Decrease Net increase in cash and cash equivalents Cash dividend distribution. Cash Dividend Distribution Cash dividend distribution Cash dividend distribution. Cash Dividend Distribution Disclosure [Text Block] Cash dividend distribution Change in redeemable amount of noncontrolling interest. Change In Redeemable Amount Of Noncontrolling Interest Change in redeemable amount of noncontrolling interest City of Sao Paulo tax claim. City Of Sao Paulo Tax Claim [Member] City of Sao Paulo Tax Claim [Member] C L Chile [Member] C O Colombia [Member] Collateralized Debt Obligations [Member] Collateralized Debt Obligations [Member] Commitments And Contingencies Commitments and contingencies (Note 7) Commitments And Contingencies Disclosure [Text Block] Commitments and Contingencies Common Stock Dividends Per Share Declared Cash dividend distribution, per share Common Stock Par Or Stated Value Per Share Common stock, par value Common Stock Shares Authorized Common stock, shares authorized Common Stock Shares Issued Common stock, shares issued Common Stock Shares Outstanding Common stock, shares outstanding Common Stock Value Common stock, $0.001 par value, 110,000,000 shares authorized, 44,150,920 and 44,142,020 shares issued and outstanding at September 30, 2012 and December 31, 2011, respectively Comprehensive Income Net Of Tax Comprehensive income attributable to MercadoLibre, Inc. Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest Less: Comprehensive Income attributable to Noncontrolling Interest Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest Total Comprehensive income Corporate Debt Securities [Member] Corporate Debt Securities [Member] Cost Of Revenue Cost of net revenues Current Fiscal Year End Date Current Fiscal Year End Date Customer Lists [Member] Customer List [Member] Daily non compliance penalty suspended upon injunction granted. Daily Non Compliance Penalty Suspended Upon Injunction Granted Daily non compliance penalty suspended upon injunction granted Deferred Income Tax Expense Benefit Deferred income taxes Deferred Tax Assets Net Current Deferred tax assets Deferred Tax Assets Net Noncurrent Deferred tax assets Deferred Tax Liabilities Noncurrent Deferred tax liabilities Depreciation And Amortization Depreciation and amortization Diluted Weighted Average Number Of Shares Outstanding Diluted Weighted Average Number Of Shares Outstanding Weighted average of common stock outstanding for diluted earnings per share Direct contribution. Direct Contribution Direct contribution Direct Operating Costs Direct costs Disclosure - Cash dividend distribution - Additional Information [Abstract] Disclosure Cash Dividend Distribution Additional Information [Abstract] Disclosure - Cash dividend distribution - Additional Information [Abstract] Disclosure Commitments And Contingencies Additional Information [Abstract] Disclosure Commitments And Contingencies Additional Information [Abstract] Disclosure Commitments And Contingencies Additional Information [Abstract] Disclosure Fair Value Measurement Of Assets And Liabilities Additional Information [Abstract] Disclosure Fair Value Measurement Of Assets And Liabilities Additional Information [Abstract] Disclosure Fair Value Measurement Of Assets And Liabilities Additional Information [Abstract] Disclosure - Fair Value Measurement of Assets And Liabilities - Estimated Fair Value of Short-Term and Long-Term Investments [Abstract] Disclosure Fair Value Measurement Of Assets And Liabilities Estimated Fair Value Of Short Term And Long Term Investments [Abstract] Disclosure - Fair Value Measurement of Assets And Liabilities - Estimated Fair Value of Short-Term and Long-Term Investments [Abstract] Disclosure - Fair Value Measurement of Assets and Liabilities - Fair Value of Short and Long-Term Investments Classified as Available for Sale Securities [Abstract] Disclosure Fair Value Measurement Of Assets And Liabilities Fair Value Of Short And Long Term Investments Classified As Available For Sale Securities [Abstract] Disclosure - Fair Value Measurement of Assets and Liabilities - Fair Value of Short and Long-Term Investments Classified as Available for Sale Securities [Abstract] Disclosure - Fair Value Measurement of Assets and Liabilities - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis [Abstract] Disclosure Fair Value Measurement Of Assets And Liabilities Financial Assets And Liabilities Measured At Fair Value On Recurring Basis [Abstract] Disclosure - Fair Value Measurement of Assets and Liabilities - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis [Abstract] Disclosure Goodwill And Intangible Assets Additional Information [Abstract] Disclosure Goodwill And Intangible Assets Additional Information [Abstract] Disclosure Goodwill And Intangible Assets Additional Information [Abstract] Disclosure - Goodwill and Intangible Assets - Composition of Goodwill and Intangible Assets [Abstract] Disclosure Goodwill And Intangible Assets Composition Of Goodwill And Intangible Assets [Abstract] Disclosure - Goodwill and Intangible Assets - Composition of Goodwill and Intangible Assets [Abstract] Disclosure - Goodwill and Intangible Assets - Expected Future Intangible Asset Amortization From Acquisitions [Abstract] Disclosure Goodwill And Intangible Assets Expected Future Intangible Asset Amortization From Acquisitions [Abstract] Disclosure - Goodwill and Intangible Assets - Expected Future Intangible Asset Amortization From Acquisitions [Abstract] Disclosure - Goodwill and Intangible Assets - Table Showing Changes in Carrying Amount of Goodwill [Abstract] Disclosure Goodwill And Intangible Assets Table Showing Changes In Carrying Amount Of Goodwill [Abstract] Disclosure - Goodwill and Intangible Assets - Table Showing Changes in Carrying Amount of Goodwill [Abstract] Disclosure - Long Term Retention Plan - Additional Information [Abstract] Disclosure Long Term Retention Plan Additional Information [Abstract] Disclosure - Long Term Retention Plan - Additional Information [Abstract] Disclosure - Long Term Retention Plan - Summary of LTRP Accrued Compensation Expense [Abstract] Disclosure Long Term Retention Plan Summary Of L T R P Accrued Compensation Expense [Abstract] Disclosure - Long Term Retention Plan - Summary of LTRP Accrued Compensation Expense [Abstract] Disclosure - Net Income per Share - Additional Information [Abstract] Disclosure Net Income Per Share Additional Information [Abstract] Disclosure - Net Income per Share - Additional Information [Abstract] Disclosure - Net Income per Share - Allocation of Net Income Available to Common Shareholders using Two-Class Method [Abstract] Disclosure Net Income Per Share Allocation Of Net Income Available To Common Shareholders Using Two Class Method [Abstract] Disclosure - Net Income per Share - Allocation of Net Income Available to Common Shareholders using Two-Class Method [Abstract] Disclosure - Net Income per Share - Net Income Per Share of Common Stock [Abstract] Disclosure Net Income Per Share Net Income Per Share Of Common Stock [Abstract] Disclosure - Net Income per Share - Net Income Per Share of Common Stock [Abstract] Disclosure - Segment Reporting - Allocation of Goodwill and Intangible Assets Based on Geography [Abstract] Disclosure Segment Reporting Allocation Of Goodwill And Intangible Assets Based On Geography [Abstract] Disclosure - Segment Reporting - Allocation of Goodwill and Intangible Assets Based on Geography [Abstract] Disclosure - Segment Reporting - Allocation of Long-Lived Tangible Assets Based on Geography [Abstract] Disclosure Segment Reporting Allocation Of Long Lived Tangible Assets Based On Geography [Abstract] Disclosure - Segment Reporting - Allocation of Long-Lived Tangible Assets Based on Geography [Abstract] Disclosure - Segment Reporting - Financial Performance of Company's Reporting Segments [Abstract] Disclosure Segment Reporting Financial Performance Of Companys Reporting Segments [Abstract] Disclosure - Segment Reporting - Financial Performance of Company's Reporting Segments [Abstract] Disclosure Summary Of Significant Accounting Policies Additional Information [Abstract] Disclosure Summary Of Significant Accounting Policies Additional Information [Abstract] Disclosure Summary Of Significant Accounting Policies Additional Information [Abstract] Disclosure - Summary of Significant Accounting Policies - Assets, Liabilities and Net Assets of Company's Venezuelan Subsidiaries [Abstract] Disclosure Summary Of Significant Accounting Policies Assets Liabilities And Net Assets Of Companys Venezuelan Subsidiaries [Abstract] Disclosure - Summary of Significant Accounting Policies - Assets, Liabilities and Net Assets of Company's Venezuelan Subsidiaries [Abstract] Dividends Payable Current Dividends payable Document Documentand Entity Information [Abstract] Document Documentand Entity Information [Abstract] Document Documentand Entity Information [Abstract] Document Fiscal Period Focus Document Fiscal Period Focus Document Fiscal Year Focus Document Fiscal Year Focus Document Information [Table] Document Information [Table] Document Period End Date Document Period End Date Document Type Document Type Earnings Per Share Basic Basic net income attributable to MercadoLibre, Inc. per common share Net income attributable to MercadoLibre, Inc per common share, Basic Earnings Per Share Basic [Abstract] Basic EPS Earnings Per Share Diluted Diluted net income attributable to MercadoLibre, Inc. per common share Net income attributable to MercadoLibre, Inc per common share, Diluted Earnings Per Share Diluted [Abstract] Diluted EPS Earnings Per Share [Text Block] Net income per share Effect Of Exchange Rate On Cash And Cash Equivalents Effect of exchange rate changes on cash and cash equivalents Employee Related Liabilities Current Salaries and social security payable Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the non current portion of the liabilities (more than one year or within the normal operating cycle if longer). Employee Related Liabilities Noncurrent Salaries and social security payable Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount Long term retention plan Entity Central Index Key Entity Central Index Key Entity Common Stock Shares Outstanding Entity Common Stock, Shares Outstanding Entity [Domain] Entity [Domain] Entity Filer Category Entity Filer Category Entity Information [Line Items] Entity Information [Line Items] Entity Registrant Name Entity Registrant Name Other countries goodwill and intangible assets. Entity Wide Disclosure On Geographic Areas Goodwill And Intangible Assets In Foreign Countries Other countries goodwill and intangible assets Entity wide disclosure on geographic areas goodwill and intangible assets. Entity Wide Disclosure On Geographic Areas Goodwill And Intangible Assets Table [Text Block] Allocation of Goodwill and Intangible Assets Based on Geography US intangible assets. Entity Wide Disclosure On Geographic Areas Intangible Assets In Entitys Country Of Domicile US intangible assets Entity Wide Disclosure On Geographic Areas Long Lived Assets In Entitys Country Of Domicile US long-lived tangible assets Entity Wide Disclosure On Geographic Areas Long Lived Assets In Foreign Countries Other countries long-lived tangible assets 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] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Total financial assets. Fair Value Assets Measured On Recurring Basis Net Asset Total financial Assets Fair Value Assets Measured On Recurring Basis [Text Block] Financial Assets and Liabilities Measured at Fair Value on Recurring Basis Fair Value By Fair Value Hierarchy Level [Axis] Fair Value, Hierarchy [Axis] Fair Value By Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value Disclosures [Text Block] Fair Value Measurement of Assets and Liabilities Fair Value Inputs Level 1 [Member] Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] Fair Value Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Fair Value Measurements Fair Value Hierarchy [Domain] Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Measurements Recurring [Member] Fair Value, Measurements, Recurring [Member] Financial Instrument [Axis] Financial Instrument [Axis] Fine against company's subsidiaries. Fine Against Companys Subsidiaries Fine against Company's subsidiaries Finite Lived Intangible Assets Accumulated Amortization Accumulated amortization Finite Lived Intangible Assets Amortization Expense After Year Five Thereafter Finite Lived Intangible Assets Amortization Expense [Line Items] Finite Lived Intangible Assets Amortization Expense [Line Items] Finite Lived Intangible Assets Amortization Expense [Line Items] Finite Lived Intangible Assets Amortization Expense Next Twelve Months For year ended 12/31/2012 Finite Lived Intangible Assets Amortization Expense Year Four For year ended 12/31/2015 Finite Lived Intangible Assets Amortization Expense Year Three For year ended 12/31/2014 Finite Lived Intangible Assets Amortization Expense Year Two For year ended 12/31/2013 Finite Lived Intangible Assets By Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite Lived Intangible Assets Gross Finite-Lived Intangible Assets, Gross Finite Lived Intangible Assets Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite Lived Intangible Assets Net Total expected future intangible asset Foreign currency exchange rate remeasuring transactions. Foreign Currency Exchange Rate Remeasuring Transactions Exchange rate used to re-measure transactions Foreign Currency Transaction Gain Before Tax Foreign currency (loss)/gain Foreign currency gain (loss) Foreign Currency Transactions And Translations Policy [Text Block] Foreign Currency Translation General And Administrative Expense General and administrative Goodwill Balance, end of the period Balance, beginning of year Goodwill Goodwill, net Goodwill Acquired During Period Purchase of Autoplaza.com Goodwill And Intangible Assets Disclosure [Text Block] Goodwill and Intangible Assets For goodwill, carrying amount as of the balance sheet date, which is the cumulative amount paid, adjusted for any amortization recognized prior to adoption of FAS 142 and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions. For the intangible assets, sum of carrying amounts, net of accumulated amortization and impairment charges. Goodwill And Intangible Assets Net Total goodwill and intangible assets Goodwill [Line Items] Goodwill [Line Items] Goodwill Translation And Purchase Accounting Adjustments Effect of exchange rates change Gross Profit Gross profit Held To Maturity Securities Short-term and long-term investments Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments Net income before income / asset tax expense Net income before income / asset tax expense Income Statement [Abstract] Income Statement [Abstract] Income Tax Expense Benefit Income / asset tax expense Income Tax Holiday Aggregate Dollar Amount Aggregate tax benefit, total Income Tax Holiday Description Percentage of tax benefits obtained from software development law Income Tax Holiday Income Tax Benefits Per Share Aggregate per share effect of the Argentine tax holiday Income Tax Policy [Text Block] Income Tax Holiday in Argentina Increase Decrease In Accounts Payable And Accrued Liabilities Accounts payable and accrued expenses Increase Decrease In Accounts Receivable Accounts receivable Funds payable relate also to the Company's payments solution and means amounts due to sellers held by the Company until the transaction is completed. Increase Decrease In Funds Payable To Customers Funds payable to customers Funds receivable relate to the Company's payments solution and arise due to the time taken to clear transactions through external payment networks. When customers fund their account using their bank account or credit card, there is a period before the cash is received by the Company. Hence, these funds are treated as a receivable until the cash is settled. These funds are presented net of the related allowance for charge backs. Increase Decrease In Funds Receivable From Customers Credit Card Receivables Increase Decrease In Operating Capital [Abstract] Changes in assets and liabilities: Increase Decrease In Other Operating Assets Other assets Increase Decrease In Other Operating Liabilities Other liabilities Increase Decrease In Prepaid Expense Prepaid expenses Incremental Common Shares Attributable To Contingently Issuable Shares Adjustment for shares granted under LTRP Incremental Common Shares Attributable To Share Based Payment Arrangements Adjustment for stock options Indefinite Lived Intangible Assets By Major Class [Axis] Indefinite-lived Intangible Assets by Major Class [Axis] Indefinite Lived Intangible Assets By Major Class [Line Items] Indefinite-lived Intangible Assets [Line Items] Indefinite Lived Intangible Assets Excluding Goodwill Trademarks Indefinite Lived Intangible Assets Major Class Name [Domain] Indefinite-lived Intangible Assets, Major Class Name [Domain] Intangible assets and goodwill gross. Intangible Assets And Goodwill Gross Total intangible assets Intangible Assets Net Excluding Goodwill Intangible assets, net Total intangible assets, net Interest expense and other financial charges. Interest Expense And Other Financial Charges Interest expense and other financial results Interest expense and other financial losses Investment Holdings [Line Items] Investment Holdings [Line Items] Investment Holdings [Table] Investment Holdings [Table] Investment Income Interest Interest income and other financial gains Investments Direct investments Investments And Fair Value Measurements [Line Items] Investments And Fair Value Measurements [Line Items] Investments And Fair Value Measurements [Line Items] Investments And Fair Value Measurements [Table] Investments And Fair Value Measurements [Table] Investments And Fair Value Measurements [Table] Investments Fair Value Disclosure Investments Investment Type [Axis] Investment Type [Axis] Investment Type Categorization [Member] Investment Type Categorization [Domain] Legal Entity [Axis] Legal Entity [Axis] Liabilities Total liabilities Liabilities Liabilities And Stockholders Equity Total liabilities, redeemable noncontrolling interest and equity Liabilities And Stockholders Equity [Abstract] Liabilities and Equity Liabilities Current Total current liabilities Liabilities Current [Abstract] Current liabilities: Liabilities Noncurrent Total non-current liabilities Liabilities Noncurrent [Abstract] Non-current liabilities: Licensing Agreements [Member] Licenses and others [Member] Loans Payable Current Loans payable and other financial liabilities Long Term Investments Long-term investments Long-term investments. Long Term Investments [Member] Long-term investments [Member] Long Term Loans Payable Loans payable and other financial liabilities Long term retention plan accrued compensation expense. Long Term Retention Plan Accrued Compensation Expense Table [Text Block] Summary of LTRP Accrued Compensation Expense Long term retention plan each quota calculation term. Long Term Retention Plan Each Quota Calculation Term Long Term Retention Plan each quota calculation term Long term retention plan payment term. Long Term Retention Plan Payment Term Long Term Retention Plan payment term Long term retention plan 2011. Long Term Retention Plan Two Zero One One [Member] Long Term Retention Plan 2011 [Member] Long term retention plan two zero one two. Long Term Retention Plan Two Zero One Two [Member] Long Term Retention Plan 2012 [Member] Long term retention plan 2010. Long Term Retention Plan Two Zero One Zero [Member] Long Term Retention Plan 2010 [Member] Long term retention plan 2009. Long Term Retention Plan Two Zero Zero Nine [Member] Long Term Retention Plan 2009 [Member] Loss Contingencies By Nature Of Contingency [Axis] Loss Contingency Nature [Axis] Loss Contingencies [Line Items] Loss Contingencies [Line Items] Loss Contingencies [Table] Loss Contingencies [Table] Loss Contingency Accrual At Carrying Value Reserves for proceeding-related contingencies Loss contingency deposits with court of law. Loss Contingency Deposits With Court Of Law Deposit with court Loss Contingency Estimate Of Possible Loss Amount of reasonably possible loss Loss contingency estimate of possible loss including surcharges and interest. Loss Contingency Estimate Of Possible Loss Including Surcharges And Interest Total amount of claim including surcharges and interest Loss contingency for asserted taxes and fines. Loss Contingency For Asserted Taxes And Fines Approximate additional amount related to asserted taxes and fines Loss Contingency Nature [Domain] Loss Contingency, Nature [Domain] Loss contingency pending cases related to consumer courts. Loss Contingency Pending Cases Related To Consumer Courts Loss contingency pending cases related to consumer courts Loss Contingency Pending Claims Number Number of legal actions pending Loss contingency reduced asserted taxes and fines. Loss Contingency Reduced Asserted Taxes And Fines Loss contingency reduced asserted taxes and fines Major Types Of Debt And Equity Securities [Axis] Major Types of Debt and Equity Securities [Axis] Major Types Of Debt And Equity Securities [Domain] Major Types of Debt and Equity Securities [Domain] Money Market Funds [Member] Money Market Funds [Member] M X Mexico [Member] Nature Of Operations Nature of Business Net assets of subsidiaries as percentage of consolidated net assets. Net Assets Of Subsidiaries As Percentage Of Consolidated Net Assets Percentage of consolidated net assets Net cash and investments of subsidiaries as percentage of consolidated cash and investments. Net Cash And Investments Of Subsidiaries As Percentage Of Consolidated Cash And Investments Percentage of consolidated cash and investments Net Cash Provided By Used In Financing Activities Net cash provided in financing activities Net Cash Provided By Used In Financing Activities [Abstract] Cash flows from financing activities: Net Cash Provided By Used In Investing Activities Net cash used in investing activities Net Cash Provided By Used In Investing Activities [Abstract] Cash flows from investing activities: Net Cash Provided By Used In Operating Activities Net cash provided by operating activities Net Cash Provided By Used In Operating Activities [Abstract] Cash flows from operations: Net income attributable to MercadoLibre, Inc., basic. Net Income Attributable To Common Stock Holders Basic Net income attributable to MercadoLibre, Inc., Basic Net income attributable to MercadoLibre, Inc. corresponding to common stock, Basic Net Income Loss Net income Net income Net Income Loss [Abstract] Numerator: Net Income Loss Attributable To Noncontrolling Interest Less: Net Income attributable to Noncontrolling Interest Net Income attributable to Noncontrolling Interest Net income attributable to noncontrolling interests Net Income Loss Available To Common Stockholders Basic Net income attributable to MercadoLibre, Inc. Net income attributable to MercadoLibre, Inc. Net Income Loss Available To Common Stockholders Diluted Net income attributable to MercadoLibre, Inc. corresponding to common stock, Diluted Net income attributable to MercadoLibre, Inc., Diluted Net income per share of common stock. Net Income Per Share Of Common Stock [Abstract] Net income attributable to MercadoLibre, Inc. per common share Net income per share of common stock. Net Income Per Share Of Common Stock Table [Text Block] Net Income Per Share of Common Stock Noncompete Agreements [Member] Non-compete agreement [Member] Non-financial assets or liabilities measured at fair value. Non Financial Assets Or Liabilities Measured At Fair Value Non-financial assets or liabilities measured at fair value Nonoperating Income Expense [Abstract] Other income (expenses): Number of quotas for payment under long term retention plan. Number Of Quotas For Payment Under Long Term Retention Plan Number of quotas for payment under LTRP Number of trading days consider for average closing price. Number Of Trading Days Consider For Average Closing Price Number of trading days consider for average closing price Operating Expenses Total operating expenses Operating Expenses [Abstract] Operating expenses: Operating expenses and indirect costs of net revenues. Operating Expenses And Indirect Costs Of Net Revenues Operating expenses and indirect costs of net revenues Operating Income Loss Income from operations Other Assets Current Other assets Other Assets Noncurrent Other assets Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax Realized net gain on investments Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax Currency translation adjustment Other Comprehensive Income Loss Net Of Tax Net change in accumulated other comprehensive loss, net of income tax Other Comprehensive Income Loss Net Of Tax Period Increase Decrease [Abstract] Other comprehensive income (loss), net of income tax: Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax Unrealized net gains on investments Other Contingencies [Member] Other Contingencies [Member] Other Contingencies [Member] Other countries long lived tangible and intangible assets. Other Countries Long Lived Tangible And Intangible Assets Long-lived assets located in the foreign operations Other Countries [Member] Other Countries [Member] Other Countries [Member] Other Liabilities Noncurrent Other liabilities Other Nonoperating Income Expense Other (loss) / income, net Other income (loss), net Payables To Customers Funds payable to customers Payments Of Dividends Common Stock Dividends paid Payments To Acquire Businesses Net Of Cash Acquired Payment for acquired businesses, net of cash acquired Payments To Acquire Intangible Assets Purchases of intangible assets Payments To Acquire Investments Purchase of investments Payments To Acquire Property Plant And Equipment Purchases of property and equipment Penalty per day for non compliance. Penalty Per Day For Non Compliance Penalty per day for non compliance Percentage base for calculation of quotas under long term retention plan. Percentage Base For Calculation Of Quotas Under Long Term Retention Plan Percentage base for calculation of quotas under LTRP Percentage on relief of income tax. Percentage On Relief Of Income Tax Percentage on relief of total income tax Percentage quotas in each installment under long term retention plan. Percentage Quotas In Each Installment Under Long Term Retention Plan Percentage quotas in each installment under LTRP Per defendant per day of alleged noncompliance. Per Defendant Per Day Of Alleged Noncompliance Per defendant per day of alleged noncompliance Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] Prepaid Expense Current Prepaid expenses Proceeds From Sale Maturity And Collections Of Investments Proceeds from sale and maturity of investments Proceeds From Stock Options Exercised Stock options exercised Property Plant And Equipment Net Property and equipment, net Total long-lived tangible assets Receivables From Customers Credits Cards Receivables Recently accounting pronouncements. Recently Accounting Pronouncements Policy [Text Block] Recent Accounting Pronouncements Redeemable Noncontrolling Interest Equity Carrying Amount Redeemable noncontrolling interest Retained earnings accumulated. Retained Earnings Accumulated Retained earnings Percentage of revenues and operating costs generated in foreign operations. Revenues And Operating Costs Generated In Foreign Operations Percentage of revenues and operating costs generated in foreign operations Revenues From External Customers And Long Lived Assets [Line Items] Revenues from External Customers and Long-Lived Assets [Line Items] Sales Revenue Services Net Net revenues Schedule Of Available For Sale Securities [Line Items] Schedule of Available-for-sale Securities [Line Items] Schedule Of Available For Sale Securities [Table] Schedule of Available-for-sale Securities [Table] Schedule Of Business Acquisitions By Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Schedule Of Defined Benefit Plans Disclosures [Text Block] Long Term Retention Plan Schedule Of Entity Wide Disclosure On Geographic Areas Long Lived Assets In Individual Foreign Countries By Country [Text Block] Allocation of Long-Lived Tangible Assets Based on Geography Schedule Of Fair Value Of Separate Accounts By Major Category Of Investment [Axis] Schedule of Fair Value of Separate Accounts by Major Category of Investment [Axis] Schedule Of Fair Value Of Separate Accounts By Major Category Of Investment Category [Domain] Schedule of Fair Value of Separate Accounts by Major Category of Investment, Category [Domain] Schedule Of Finite Lived Intangible Assets Amortization Expense [Table] Schedule Of Finite Lived Intangible Assets Amortization Expense [Table] Schedule Of Finite Lived Intangible Assets Amortization Expense [Table] Scheduleof Finite Lived Intangible Assets Future Amortization Expense Table [Text Block] Expected Future Intangible Asset Amortization from Acquisitions Schedule Of Goodwill [Table] Schedule of Goodwill [Table] Schedule Of Goodwill [Text Block] Table Showing Changes In Carrying Amount of Goodwill Schedule Of Indefinite Lived Intangible Assets [Table] Schedule of Indefinite-Lived Intangible Assets [Table] Schedule Of Intangible Assets And Goodwill Table [Text Block] Composition of Goodwill and Intangible Assets Schedule Of Revenues From External Customers And Long Lived Assets [Table] Schedule of Revenues from External Customers and Long-Lived Assets [Table] Schedule Of Segment Reporting Information By Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Schedule Of Segment Reporting Information By Segment [Text Block] Financial Performance of Company's Reporting Segments Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Segment Geographical [Domain] Segment, Geographical [Domain] Segment Reporting Disclosure [Text Block] Segment reporting Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Selling And Marketing Expense Sales and marketing Share Based Compensation LTRP accrued compensation Share Based Compensation Arrangement By Share Based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Short Term Investments Short-term investments Short Term Investments [Member] Short-term investments [Member] Significant Accounting Policies [Text Block] Summary of Significant Accounting Policies Sovereign Debt Securities [Member] Sovereign Debt Securities [Member] Statement Geographical [Axis] Geographical [Axis] Statement [Line Items] Statement [Line Items] Statement Of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Statement Of Financial Position [Abstract] Statement of Financial Position [Abstract] Statement Of Income And Comprehensive Income [Abstract] Statement of Other Comprehensive Income [Abstract] Statement [Table] Statement [Table] Stockholders Equity Total Equity Stockholders Equity [Abstract] Equity: Structured Investment Vehicles [Member] Structured Investment Vehicles [Member] Structured Investment Vehicles [Member] Taxes Payable Current Taxes payable Technology Services Costs Product and technology development Text Block [Abstract] Text Block [Abstract] Threshold percentage for impairment test. Threshold Percentage For Impairment Test Threshold percentage for impairment test Trademarks [Member] Trademarks [Member] Transfers And Servicing Of Financial Instruments Types Of Financial Instruments [Domain] Types of Financial Instruments [Domain] The preparation of condensed consolidated financial statements in conformity with generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Estimates are used for, but not limited to accounting for allowance for doubtful accounts, depreciation, amortization, impairment and useful lives of long-lived assets, compensation cost related to cash and share-based compensation and restricted shares, recognition of current and deferred income taxes and contingencies. Actual results could differ from those estimates. Use Of Estimates Policy [Text Block] Use of estimates V E Venezuela [Member] Venezuelan Subsidiary [Member] Venezuelan Subsidiary [Member] Venezuelan Subsidiary [Member] Weighted Average Number Of Diluted Shares Outstanding Weighted average shares Adjusted weighted average of common stock outstanding for Diluted earnings per share Weighted Average Number Of Shares Outstanding [Abstract] Denominator: Weighted Average Number Of Shares Outstanding Basic Weighted average of common stock outstanding for Basic earnings per share Weighted average shares