Parent Company - Condensed Statements of Financial Condition (Details) - USD ($) $ / shares in Units, $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Assets
Cash	$ 889,559	$ 732,164
Deferred tax asset	193,070	214,671
Other assets	317,747	252,640
Total assets	9,965,798	9,609,370
Liabilities
Accounts payable and accrued expenses and other liabilities	491,818	399,168
Tax receivable agreement obligations	271,165	269,282
Total liabilities	8,110,760	8,380,434
Virtu Financial Inc. Stockholders' equity
Treasury stock, at cost, 3,615,097 and 2,178,771 shares at December 31, 2020 and December 31, 2019, respectively	(88,923)	(55,005)
Additional paid-in capital	1,160,567	1,077,398
Retained earnings (accumulated deficit)	422,381	(90,374)
Accumulated other comprehensive income (loss)	(25,487)	(647)
Total Virtu Financial Inc. stockholders' equity	1,468,540	931,374
Total liabilities and stockholders' equity	$ 9,965,798	$ 9,609,370
Treasury stock, shares (in shares)	3,615,097	2,178,771
Class A common stock
Virtu Financial Inc. Stockholders' equity
Common stock	$ 1	$ 1
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Common Stock, Shares Authorized	1,000,000,000	1,000,000,000
Common stock, shares issued (in shares)	125,627,277	120,435,912
Common Stock, Shares, Outstanding	122,012,180	118,257,141
Class B common stock
Virtu Financial Inc. Stockholders' equity
Common stock	$ 0	$ 0
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Common Stock, Shares Authorized	175,000,000	175,000,000
Common stock, shares issued (in shares)	0	0
Common Stock, Shares, Outstanding	0	0
Class C common stock
Virtu Financial Inc. Stockholders' equity
Common stock	$ 0	$ 0
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Common Stock, Shares Authorized	90,000,000	90,000,000
Common stock, shares issued (in shares)	10,226,939	12,887,178
Common Stock, Shares, Outstanding	10,226,939	12,887,178
Class D common stock
Virtu Financial Inc. Stockholders' equity
Common stock	$ 1	$ 1
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Common Stock, Shares Authorized	175,000,000	175,000,000
Common stock, shares issued (in shares)	60,091,740	60,091,740
Common Stock, Shares, Outstanding	60,091,740	60,091,740
VFH
Assets
Cash	$ 71,481	$ 4,650
Deferred tax asset	183,549	197,792
Investment in subsidiary	3,126,502	2,689,026
Other assets	82,917	33,653
Total assets	3,464,449	2,925,121
Liabilities
Payable to affiliate	1,724,046	1,724,465
Accounts payable and accrued expenses and other liabilities	698	0
Tax receivable agreement obligations	271,165	269,282
Total liabilities	1,995,909	1,993,747
Virtu Financial Inc. Stockholders' equity
Treasury stock, at cost, 3,615,097 and 2,178,771 shares at December 31, 2020 and December 31, 2019, respectively	88,923	55,005
Additional paid-in capital	1,160,567	1,075,779
Retained earnings (accumulated deficit)	422,381	(88,755)
Accumulated other comprehensive income (loss)	(25,487)	(647)
Total Virtu Financial Inc. stockholders' equity	1,468,540	931,374
Total liabilities and stockholders' equity	$ 3,464,449	$ 2,925,121
Treasury stock, shares (in shares)	3,615,097	2,178,771
VFH | Class A common stock
Virtu Financial Inc. Stockholders' equity
Common stock	$ 1	$ 1
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Common Stock, Shares Authorized	1,000,000,000	1,000,000,000
Common stock, shares issued (in shares)	125,627,277	120,435,912
Common Stock, Shares, Outstanding	122,012,180	118,257,141
VFH | Class B common stock
Virtu Financial Inc. Stockholders' equity
Common stock	$ 0	$ 0
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Common Stock, Shares Authorized	175,000,000	175,000,000
Common stock, shares issued (in shares)	0	0
Common Stock, Shares, Outstanding	0	0
VFH | Class C common stock
Virtu Financial Inc. Stockholders' equity
Common stock	$ 0	$ 0
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Common Stock, Shares Authorized	90,000,000	90,000,000
Common stock, shares issued (in shares)	10,226,939	12,887,178
Common Stock, Shares, Outstanding	10,226,939	12,887,178
VFH | Class D common stock
Virtu Financial Inc. Stockholders' equity
Common stock	$ 1	$ 1
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Common Stock, Shares Authorized	175,000,000	175,000,000
Common stock, shares issued (in shares)	60,091,740	69,091,740
Common Stock, Shares, Outstanding	60,091,740	69,091,740