Organization (Details) - USD ($) $ / shares in Units, $ in Billions		3 Months Ended
	Apr. 08, 2019	Mar. 31, 2020	Jun. 30, 2019
Shares contributed by Refinitiv Owner			96,933,192
Class A common stock
Shares issued		2,341,171
Common Stock, par value per share		$ 0.00001
Class B common stock
Shares issued	96,933,192
Common Stock, par value per share		0.00001
Shares contributed by Refinitiv Owner	96,933,192
Class C common stock
Common Stock, par value per share		0.00001
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 to acquire TWM LLC	105,289,005
Number of shares canceled	36,006,269
Tradeweb Markets LLC
Ownership interest	64.30%	74.50%
Equity interest of noncontrolling shareholders in consolidated entity		25.50%
Weighted Average Share Price	$ 27.00
Net proceeds	$ 1.2
Initial Public Offering | Class A common stock
Shares issued	46,000,000
Common Stock, par value per share	$ 0.00001
Weighted Average Share Price	$ 27.00
Underwriter | Class A common stock
Shares issued	6,000,000