Organization (Details) - USD ($) $ / shares in Units, $ in Billions		1 Months Ended	3 Months Ended	9 Months Ended
	Apr. 08, 2019	Oct. 31, 2019	Jun. 30, 2019	Dec. 31, 2019	Jun. 28, 2019
Weighted Weighted Average Share Price				$ 21.62
Shares contributed by Refinitiv Owner			96,933,192
Class A common stock
Common Stock, par value per share				$ 0.00001
Shares issued				46,000,000
Class B common stock
Common Stock, par value per share				$ 0.00001	$ 0.00001
Shares issued	96,933,192			96,933,192
Number of shares canceled	9,993,731
Shares contributed by Refinitiv Owner	96,933,192
Class C common stock
Common Stock, par value per share				$ 0.00001
Shares issued				10,006,269
Shares issued to acquire TWM LLC	20,000,000
Number of shares canceled	9,993,731
Class D common stock
Common Stock, par value per share				$ 0.00001
Shares issued				69,282,736
Shares issued to acquire TWM LLC	105,289,005
Number of shares canceled	36,006,269
Tradeweb Markets LLC
Ownership interest	64.30%			73.40%
Equity interest of noncontrolling shareholders in consolidated entity				26.60%
Weighted Weighted Average Share Price	$ 27.00
Net proceeds	$ 1.2
Initial Public Offering | Class A common stock
Common Stock, par value per share	$ 0.00001
Shares issued	46,000,000
Weighted Weighted Average Share Price	$ 27.00
Over allotment | Class A common stock
Shares issued	6,000,000	2,593,181