Document and Entity Information Statement [Table] Statement [Line Items] Statement Document Type Document Period End Date Entity Registrant Name Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Current Reporting Status Entity Filer Category Entity Interactive Data Current Entity Small Business Entity Emerging Growth Company Entity Ex Transition Period Entity Shell Company Entity Common Stock, Shares Outstanding Entity Public Float Entity Central Index Key Current Fiscal Year End Date Document Fiscal Year Focus Document Fiscal Period Focus Amendment Flag Consolidated Statements of Financial Condition Assets [Abstract] Assets Financial Designation, Predecessor and Successor [Fixed List] Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents Cash and cash equivalents Restricted Cash. Restricted cash Receivables from Brokers-Dealers and Clearing Organizations Receivable from brokers and dealers and clearing organizations Deposits with Clearing Organizations and Others, Securities Deposits with clearing organizations Account receivable excluding receivable from brokers and dealers and clearing organizations, net of allowance. Account receivable excluding receivable from brokers and dealers and clearing organizations, net of allowance Accounts receivable, net of allowance Property, Plant and Equipment, Net Furniture, equipment, purchased software and leasehold improvements, net of accumulated depreciation and amortization Operating Lease, Right-of-Use Asset Right-of-use assets Capitalized Computer Software, Net Software development costs, net of accumulated amortization Software development costs, net of accumulated amortization Goodwill Goodwill Intangible Assets, Net (Excluding Goodwill) Intangible assets, net of accumulated amortization Due from Affiliates Receivable from affiliates Deferred Income Tax Assets, Net Deferred tax asset Other Assets Other assets Assets Total assets Liabilities and Equity [Abstract] Liabilities and Stockholders' Equity/Members' Capital Liabilities [Abstract] Liabilities Payables to Broker-Dealers and Clearing Organizations Payable to brokers and dealers and clearing organizations Employee-related Liabilities Accrued compensation Contract with Customer, Liability Deferred revenue balance - end of period Deferred revenue balance - beginning of period Deferred revenue Accounts Payable and Accrued Liabilities Accounts payable, accrued expenses and other liabilities Equity compensation payable to employees. Equity Compensation Payable Employee equity compensation payable Operating Lease, Liability Lease liability Due to Affiliate Payable to affiliates Deferred Income Tax Liabilities, Net Deferred tax liability The carrying amount as on the balance sheet date of tax receivable agreement liability. Tax Receivable Agreement Liability Tax receivable agreement liability Tax receivable agreement liability adjustment Liabilities Total liabilities Commitments and Contingencies. Commitments and contingencies (Note 17) Temporary Equity [Abstract] Mezzanine Capital Temporary Equity, Carrying Amount, Attributable to Parent Class C Shares and Class P(C) Shares Members' Equity [Abstract] Stockholders' Equity/Members' Capital Members' Capital Members’ capital Preferred Stock, Value, Issued Preferred stock, $.00001 par value; 250,000,000 shares authorized; none issued or outstanding Common Stock, Value, Issued Common stock Additional paid-in capital Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated other comprehensive income (loss) Retained Earnings (Accumulated Deficit) Retained earnings Stockholders' Equity Attributable to Parent Total stockholders' equity attributable to Tradeweb Markets Inc./members' capital Total stockholder's equity Stockholders' Equity Attributable to Noncontrolling Interest Non-controlling interests Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Equity at end of period Equity at beginning of period Total equity Liabilities and Equity Total liabilities and stockholders' equity/members' capital Preferred Stock, Par or Stated Value Per Share Preferred stock, par value Preferred Stock, Shares Authorized Preferred stock, shares authorized Preferred Stock, Shares Issued Preferred stock, shares issued Preferred Stock, Shares Outstanding Preferred stock, shares outstanding Common Stock, Par or Stated Value Per Share Common stock, par value Common Stock, par value per share Common Stock, Shares Authorized Common Stock, shares authorized Common Stock, Shares, Outstanding Common stock, shares outstanding Consolidated Statements of Income Revenues [Abstract] Revenue: Revenues Revenue from Contract with Customer, Excluding Assessed Tax Gross revenues Gross revenue Contingent consideration to related parties. Contingent Consideration Related Parties Contingent consideration Contingent consideration recognized Revenues Net revenue Net revenue Revenue Operating Expenses [Abstract] Expenses Labor and Related Expense Employee compensation and benefits Depreciation, Depletion and Amortization, Nonproduction Depreciation and amortization Communications and Information Technology Technology and communications Other General and Administrative Expense General and administrative Professional Fees Professional fees Occupancy, Net Occupancy Costs and Expenses Operating expenses Total expenses Operating Income (Loss) Operating income Operating income Represents the adjustments related to tax receivable agreement liability. Tax Receivable Agreement Liability, Adjustment Tax receivable agreement liability adjustment Tax receivable agreement liability adjustment Investment Income, Interest Net interest income Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Income before taxes Total income before provision for income taxes Income Tax Expense (Benefit) Provision for income taxes Total provision for income taxes Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Net income Net income The amount of net income (loss) attributable to limited liability company. Net Income (Loss) Attributable To Limited Liability Company Pre-IPO net income attributable to Tradeweb Markets LLC Less: Pre-IPO net income attributable to Tradeweb Markets LLC Represents the amount of profit loss after pre-IPO. Profit Loss After Pre IPO Net income attributable to Tradeweb Markets Inc. and non-controlling interests Net Income (Loss) Attributable to Noncontrolling Interest Net income attributable to non-controlling interests Less: Net income attributable to non-controlling interests Net Income (Loss) Attributable to Parent Net income attributable to Tradeweb Markets Net income attributable to Tradeweb Markets Inc. Net income attributable to Tradeweb Markets Inc. Earnings Per Share Earnings per share EPS calculations for pre-IPO and post-IPO periods Earnings Per Share, Basic Earnings per share - Basic Basic Earnings Per Share, Diluted Earnings per share - Diluted Diluted Weighted Average Number of Shares Outstanding Reconciliation [Abstract] Weighted average shares outstanding Weighted Average Number of Shares Outstanding, Basic Weighted average outstanding - Basic Basic Weighted Average Number of Shares Outstanding, Diluted Diluted Weighted average outstanding - Diluted Consolidated Statements of Comprehensive Income Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent Foreign currency translation adjustments attributable to non-controlling interests Comprehensive Income (Loss), Net of Tax, Attributable to Parent Total comprehensive income Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Noncontrolling Interest Foreign currency translation adjustments attributable to noncontrolling interests Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest Comprehensive income attributable to non-controlling interests Consolidated Statements of Changes in Equity Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity Members' Equity Members' capital end of period Members' capital beginning of period Shares, Outstanding Equity at end of period (in shares) Equity at beginning of period ( in shares) Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Comprehensive income: Adjustments to Additional Paid in Capital, Increase in Carrying Amount of Redeemable Preferred Stock Adjustment to Class C Shares and Class P© shares in mezzanine capital Distribution Made to Limited Liability Company (LLC) Member, Cash Distributions Declared Capital distributions Represents the effect of reorganization transasctions. Effect of Reorganization Transactions Effect of the reorganization transactions Stock Issued During Period, Value, New Issues Issuance of common stock Stock Issued During Period, Shares, New Issues Issuance of common stock (in shares) Shares issued Stock Issued During Period, Value, Conversion of Convertible Securities Activities related to the follow-on offering and other exchanges of LLC Interests, net of offering costs and cancellations Stock Issued During Period, Shares, Conversion of Convertible Securities Activities related to the follow-on offering and other exchanges of LLC Interests, net of offering costs and cancellations (in shares) Amount of decrease to additional paid in capital (APIC) resulting from tax receivable agreement liability and deferred taxes arising from the reorganization transactions and IPO. Adjustments to Additional Paid in Capital Tax Receivable Agreement Liability and Deferred Taxes Reorganization Transaction and IPO Tax receivable agreement liability and deferred taxes arising from the reorganization transactions, IPO and follow-on offering and other LLC Interest ownership changes Additional paid-in-capital adjustment Amount of increase in noncontrolling interest from allocation of equity to noncontrolling interest holders. Minority Interest Increase From Allocation of Equity Allocation of equity to non-controlling interests Amount of increase (decrease) in noncontrolling interest from adjustments. Minority Interest Increase Decrease From Adjustments Adjustments to non-controlling interests Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders Distributions to non-controlling interests Dividends Dividends ($0.24 per share) Adjustments to Additional Paid in Capital, Share-based Compensation, Restricted Stock Unit or Restricted Stock Award, Requisite Service Period Recognition Stock-based compensation expense under the PRSU Plan Amount reclassified to members capital Adjustments to Additional Paid in Capital, Share-based Compensation, Stock Options, Requisite Service Period Recognition Stock-based compensation expense under the Option Plan Limited Liability Company (LLC) Members' Equity, Unit-based Compensation Stock-based compensation Adjustment to Additional Paid in Capital, Income Tax Effect from Share-based Compensation, Net Payroll taxes paid for stock-based compensation exercises Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Foreign currency translation adjustments The amount of contingent consideration vested in shares. Vesting Of Contingent Consideration, Vested Vesting of contingent consideration Stock Issued During Period, Value, Conversion of Units Conversion of certain cash-settled PRSUs to equity-settled PRSUs Partners' Capital Account, Contributions Capital contributions Consolidated Statements of Cash Flows Net Cash Provided by (Used in) Operating Activities [Abstract] Cash flows from operating activities Adjustments, Noncash Items, 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: Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability Contingent consideration The amount of adjustment of vesting of shares. Vesting Of Shares Vesting of P-1 (C) Shares Share-based Compensation Stock-based compensation expense Deferred Income Tax Expense (Benefit) Deferred taxes Total deferred tax expense Deferred tax asset Increase (Decrease) in Operating Assets [Abstract] (Increase) decrease in operating assets: Increase (Decrease) in Receivables from Brokers-Dealers and Clearing Organizations Receivable from/Payable to brokers and dealers and clearing organizations, net Increase (Decrease) in Deposit Assets Deposits with clearing organizations Increase (Decrease) in Accounts Receivable Accounts receivable Increase (Decrease) Due from Affiliates Receivable from/Payable to affiliates, net Increase (Decrease) in Other Operating Assets Other assets Increase (Decrease) in Operating Liabilities [Abstract] Increase (decrease) in operating liabilities: Increase (Decrease) in Employee Related Liabilities Accrued compensation Increase (Decrease) in Deferred Revenue Deferred revenue Increase (Decrease) in Accounts Payable and Accrued Liabilities Accounts payable, accrued expenses and other liabilities The increase (decrease) during the period in equity compensation payable. Increase Decrease In Equity Compensation Payable Employee equity compensation payable Net Cash Provided by (Used in) Operating Activities Net cash provided by operating activities Net Cash Provided by (Used in) Investing Activities [Abstract] Cash flows from investing activities Payments to Acquire Property, Plant, and Equipment Purchase of furniture, equipment, software and leasehold improvements Payments for Software Capitalized software development costs Payments for (Proceeds from) Businesses and Interest in Affiliates Business acquisitions Payments to Acquire Investments Purchase of investments Net Cash Provided by (Used in) Investing Activities Net cash used in investing activities Net Cash Provided by (Used in) Financing Activities [Abstract] Cash flows from financing activities The cash inflow from mezzanine capital contribution. Mezzanine Capital Contribution Mezzanine capital contributions The cash outflow from mezzanine capital distribution. Mezzanine Capital Distribution Mezzanine capital distributions Payments of Capital Distribution Pre-IPO capital distributions Proceeds from Issuance of Common Stock Proceeds from issuance of Class A common stock in the IPO, net of underwriting discounts Payments for Repurchase of Redeemable Noncontrolling Interest Purchase of LLC Interests and Class A common stock in connection with the IPO The cash inflow associated with the amount received from entity's follow on offering of stock. Proceeds from Issuance Follow On Offering Proceeds from issuance of Class A common stock in the follow-on offering Payments for Repurchase of Equity Purchase of LLC Interests in connection with the follow-on offering Payments of Stock Issuance Costs Offering costs from IPO and follow-on offering Payments of Ordinary Dividends Dividends Amount of cash outflow in the form of capital distribution to noncontrolling interests. Payments Of Capital Distribution To Noncontrolling Interest Capital distributions to non-controlling interests Payment, Tax Withholding, Share-based Payment Arrangement Payroll taxes paid for stock-based compensation exercises Net Cash Provided by (Used in) Financing Activities Net cash used in financing activities Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations Effect of exchange rate changes on cash and cash equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Net increase (decrease) in cash and cash equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations [Abstract] Cash and cash equivalents and restricted cash Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents End of period Beginning of period Cash, cash equivalents and restricted cash shown in the statement of cash flows Supplemental Cash Flow Information [Abstract] Supplemental disclosure of cash flow information Interest Paid, Excluding Capitalized Interest, Operating Activities Interest paid Income Taxes Paid Income taxes paid Noncash Investing and Financing Items [Abstract] Non-cash financing activities - Items arising from the reorganization transactions, IPO, follow-on offering and other LLC Interest ownership changes: Liabilities Assumed Establishment of liabilities under tax receivable agreement Total contributions made by members of a limited liability company. Limited Liability Company Contributions Conversion of convertible term note payable to Thomson Reuters to Class A Shares Conversion of Stock, Amount Converted Conversion of certain cash-settled PRSUs to equity-settled PRSUs Organization Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Organization Significant Accounting Policies Entities [Table] Entity Information [Line Items] Significant Accounting Policies [Text Block] Significant Accounting Policies No definition available. Pushdown Accounting The entire disclosure for reporting pushdown accounting. Pushdown Accounting [Text Block] Pushdown Accounting Intangible Assets and Goodwill Goodwill and Intangible Assets Disclosure [Text Block] Intangible Assets and Goodwill Leases Lessee, Operating Leases [Text Block] Leases Restricted Cash Restricted Assets Disclosure [Text Block] Restricted Cash Deferred Revenue The entire disclosure about the contract with customer liability. Contract With Customer Liability [Text Block] Deferred Revenue Software Development Cost