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Significant Accounting Policies - Useful Lives of Assets (Details) - Tradeweb Markets LLC | 12 Months Ended
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Dec. 31, 2018
Furniture, Equipment, Purchased Software and Leasehold Improvements | Minimum |
Furniture, Equipment, Purchased Software and Leasehold Improvements |
Property, Plant and Equipment, Useful Life | 3 years
Furniture, Equipment, Purchased Software and Leasehold Improvements | Maximum |
Furniture, Equipment, Purchased Software and Leasehold Improvements |
Property, Plant and Equipment, Useful Life | 7 years
Software Development Costs |
Furniture, Equipment, Purchased Software and Leasehold Improvements |
Property, Plant and Equipment, Useful Life | 3 years
Amortization of pushdown accounting allocation | 9 years

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- Definition Amortization period for pushdown accounting adjustments. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
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- Details
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- Details
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- Details
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