The equity interest of noncontrolling shareholders.

No definition available.

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- Definition

The parent entity's interest in the subsidiary.

+ References

No definition available.

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The total number of shares of the subsidiary.

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No definition available.

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- Definition

The total ownership interest on noncontrolling interest expressed as a percentage.

+ References

No definition available.

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- Definition

The amount of net income (loss) attributable to parent and transfers (to) from noncontrolling interests.

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No definition available.

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- Definition

The conversion ratio of shares of non-controlling interests.

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No definition available.

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Amount of net transfers from (to) non controlling interest.

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No definition available.

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- Definition

The amount of transfers from (to) noncontrolling interest due to allocation of equity to noncontrolling interest arising from reorganization and initial public offering.

+ References

No definition available.

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- Definition

Indicates designation of financial information when substantially all business or separately identifiable line of business transfers from one entity to another entity. Acceptable values are "Predecessor" and "Successor".

+ References

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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.

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

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- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount of increase in noncontrolling interest from subsidiary issuance of equity interests to noncontrolling interest holders.

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Non-Controlling Interests (Details) $ in Thousands		3 Months Ended		9 Months Ended		12 Months Ended
Non-Controlling Interests (Details) $ in Thousands	Apr. 08, 2019 shares	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Sep. 30, 2018	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018	Dec. 31, 2017
Non-Controlling Interests
Financial Designation, Predecessor and Successor [Fixed List]		Successor	Successor	Successor	Predecessor	Successor	Successor	Predecessor
Net income attributable to Tradeweb Markets Inc.						$ 83,769
Allocation of equity to non-controlling interests arising from the reorganization transactions and IPO						(1,607,529)
Change in non-controlling interests as a result of the October 2019 follow-on offering and other ownership changes						402,227
Net transfers (to) from non-controlling interests						(1,205,302)
Change from net income attributable to Tradeweb Markets Inc. and transfers (to) from non-controlling interests						$ (1,121,533)
Class A common stock
Non-Controlling Interests
Conversion ratio						1
Class B common stock
Non-Controlling Interests
Conversion ratio						1
Tradeweb Markets LLC
Non-Controlling Interests
Number of LLC Interests held by Tradeweb Markets Inc. \| shares	142,933,192					163,341,520
Number of LLC Interests held by non-controlling interests \| shares						59,182,155
Total LLC Interests outstanding \| shares						222,523,675
Number of LLC Interests held by Tradeweb Markets Inc.	64.30%			73.40%		73.40%
Equity interest of noncontrolling shareholders in consolidated entity				26.60%		26.60%
Total LLC Interests outstanding				100.00%		100.00%