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Significant Accounting Policies - Income Tax (Details) - Tradeweb Markets LLC | 12 Months Ended
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Dec. 31, 2018 USD ($)
Entity Information [Line Items] |
Federal statutory income tax rate | 21.00%
Remeasurement of deferred tax asset | $ (1,982,000)
Adjustment to previously recorded provisional tax expense | $ 0

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- Definition Amount of income tax expense for remeasurement of deferred tax asset from change in tax rate pursuant to Tax Cuts and Jobs Act of 2017. + References No definition available. + Details
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- Definition Amount of income tax expense (benefit) from effect of Tax Cuts and Jobs Act of 2017. + References No definition available. + Details
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