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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.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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Organization (Details)	3 Months Ended		9 Months Ended
Organization (Details)	Sep. 30, 2026 $ / shares shares	Sep. 30, 2025 shares	Sep. 30, 2026 investment_provider $ / shares shares	Sep. 30, 2025 shares	Dec. 31, 2025 $ / shares
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net
Stock split ratio, common stock			1
Number of investment providers \| investment_provider			40
Weighted average unvested RSUs and unsettled vested PRSUs that were considered participating securities (in shares)	77,847	159,088	76,448	165,713
Dilutive effect (in shares)	493,942		488,333
Class A Common Stock
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net
Common stock, par value (in dollars per share) \| $ / shares	$ 0.00001		$ 0.00001		$ 0.00001
Class B Common Stock
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net
Common stock, par value (in dollars per share) \| $ / shares	0.00001		0.00001		0.00001
Class C Common Stock
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net
Common stock, par value (in dollars per share) \| $ / shares	0.00001		0.00001		0.00001
Class D Common Stock
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net
Common stock, par value (in dollars per share) \| $ / shares	$ 0.00001		$ 0.00001		$ 0.00001
Tradeweb Markets LLC
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net
Ownership interest	90.10%	90.20%	90.10%	90.20%	90.20%
Ownership percentage, continuing LLC owners	9.90%	9.80%	9.90%	9.80%	9.80%
Tradeweb Markets LLC \| LSEG
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net
Ownership interest	51.70%		51.70%
Tradeweb Markets LLC \| Public Investors
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net
Ownership percentage, continuing LLC owners	48.30%		48.30%
Tradeweb Markets LLC \| Class D Common Stock \| Other Stockholders
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net
Ownership percentage, continuing LLC owners	10.00%		10.00%
Tradeweb Markets Inc \| LSEG
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net
Ownership interest	90.20%		90.20%
Tradeweb Markets Inc \| Public Investors
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net
Voting power percentage	9.80%		9.80%
Tradeweb Markets Inc \| Class A Common Stock \| Public Investors
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net
Number of share owned (in shares)	112,142,045		112,142,045
Tradeweb Markets Inc \| Class B Common Stock \| LSEG
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net
Number of share owned (in shares)	96,933,192		96,933,192
Tradeweb Markets Inc \| Class C Common Stock \| LSEG
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net
Number of share owned (in shares)	18,000,000		18,000,000
Tradeweb Markets Inc \| Class D Common Stock \| LSEG
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net
Number of share owned (in shares)	4,988,329		4,988,329
Tradeweb Markets Inc \| Class D Common Stock \| Other Stockholders
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net
Number of share owned (in shares)	68,539		68,539
Voting power percentage	0.10%		0.10%