Condensed Consolidated Statements of Changes in Equity - USD ($)	Common Stock Class A	Common Stock Class C	Common Stock Class D	Treasury Stock	Additional Paid-in Capital	Retained Earnings (Accumulated Deficit).	Accumulated Other Comprehensive Income (Loss)	Total Stockholders' Equity	Noncontrolling Interest	Class A	Class C	Class D	Total
Balance at Dec. 31, 2015			$ 1,000	$ (3,819,000)	$ 130,902,000	$ 3,525,000	$ 99,000	$ 130,708,000	$ 427,162,000				$ 557,870,000
Balance (in shares) at Dec. 31, 2015	38,379,858	20,976,598	79,610,490	(169,649)
Increase (decrease) in stockholder's/members' equity
Share based compensation					24,893,000			24,893,000					24,893,000
Share based compensation (in shares)	953,054	(58,070)
Repurchase of common stock					(98,000)			(98,000)					(98,000)
Repurchase of common stock (in shares)		(4,153)
Treasury stock purchases				$ (4,539,000)				(4,539,000)					(4,539,000)
Treasury stock purchases (in shares)				(283,417)
Net income (loss)						32,980,000		32,980,000	125,360,000				158,340,000
Foreign exchange translation adjustment							(351,000)	(351,000)	(814,000)				(1,165,000)
Distribution from Virtu Financial to non-controlling interest									(162,969,000)				(162,969,000)
Dividends						(37,759,000)		(37,759,000)					(37,759,000)
Issuance of common stock					16,677,000			16,677,000					16,677,000
Issuance of common stock (in shares)	1,103,668
Repurchase of units and corresponding number of common stock in connection with secondary offering					(17,383,000)			(17,383,000)					(17,383,000)
Repurchase of units and corresponding number of common stock in connection with secondary offering (in shares)		(1,103,668)
Issuance of tax receivable agreements in connection with secondary offering					545,000			545,000					545,000
Balance at Dec. 31, 2016			$ 1,000	$ (8,358,000)	155,536,000	(1,254,000)	(252,000)	145,673,000	388,739,000				534,412,000
Balance (in shares) at Dec. 31, 2016	40,436,580	19,810,707	79,610,490	(453,066)						39,983,514	19,810,707	79,610,490
Increase (decrease) in stockholder's/members' equity
Share based compensation	$ 58,536				12,314,000			12,314,000					12,314,000
Share based compensation (in shares)		(34,019)
Repurchase of common stock					(4,592,000)			(4,592,000)					(4,592,000)
Repurchase of common stock (in shares)		(286,150)
Treasury stock purchases				$ (147,000)				(147,000)					(147,000)
Treasury stock purchases (in shares)				(8,326)
Net income (loss)						(8,037,000)		(8,037,000)	(6,466,000)				(14,503,000)
Foreign exchange translation adjustment							2,848,000	2,848,000	5,452,000				8,300,000
Distribution from Virtu Financial to non-controlling interest									(65,573,000)				(65,573,000)
Dividends						(42,013,000)		(42,013,000)					(42,013,000)
Issuance of common stock	$ 1,000				735,973,000			735,974,000					735,974,000
Issuance of common stock (in shares)	48,076,924
Issuance of common stock in connection with employee exchanges (in shares)	1,146,315
Repurchase of Virtu Financial Units and corresponding number of Class C common stock in connection with employee exchanges (in shares)		(1,146,315)
Issuance of tax receivable agreements in connection with employee exchange					1,355,000			1,355,000					1,355,000
Balance at Sep. 30, 2017	$ 1,000		$ 1,000	$ (8,505,000)	$ 900,586,000	$ (51,304,000)	$ 2,596,000	$ 843,375,000	$ 322,152,000				$ 1,165,527,000
Balance (in shares) at Sep. 30, 2017	89,718,355	18,344,223	79,610,490	(461,392)						89,256,963	18,344,223	79,610,490