Virtu Financial (VIRT) 10-Q 7 May 18 2018 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2018	May 07, 2018
Entity Information [Line Items]
Entity Registrant Name	Virtu Financial, Inc.
Entity Central Index Key	1,592,386
Document Type	10-Q
Document Period End Date	Mar. 31, 2018
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q1
Class A
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		91,512,582
Class C
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		17,043,963
Class D
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		79,610,490

Condensed Consolidated Statemen

Condensed Consolidated Statements of Financial Condition - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Assets
Cash and cash equivalents	$ 637,308	$ 532,887
Securities borrowed	1,232,048	1,471,172
Securities purchased under agreements to resell	602	0
Receivables from broker dealers and clearing organizations	1,434,039	972,018
Trading assets, at fair value:
Financial instruments owned	2,297,070	2,117,579
Financial instruments owned and pledged	610,536	595,043
Property, equipment and capitalized software (net of accumulated depreciation of $373,232 and $375,656 as of March 31, 2018 and December 31, 2017, respectively)	128,675	137,018
Goodwill	836,583	844,883
Intangibles (net of accumulated amortization of $130,246 and $123,409 as of March 31, 2018 and December 31, 2017, respectively)	104,387	111,224
Deferred tax assets	123,289	125,760
Assets of business held for sale	0	55,070
Other assets ($100,811 and $98,364, at fair value, as of March, 31, 2018 and December 31, 2017, respectively)	353,394	357,352
Total assets	7,757,931	7,320,006
Liabilities
Short-term borrowings	20,944	27,883
Securities loaned	936,061	754,687
Securities sold under agreements to repurchase	265,401	390,642
Payables to broker dealers and clearing organizations	648,788	716,205
Trading liabilities, at fair value:
Financial instruments sold, not yet purchased	2,846,453	2,384,598
Tax receivable agreement obligations	147,040	147,040
Accounts payable and accrued expenses and other liabilities	313,305	358,825
Long-term borrowings	1,121,464	1,388,548
Total liabilities	6,299,456	6,168,428
Virtu Financial Inc. Stockholders' equity
Treasury stock, at cost, 1,175,007 and 616,923 shares at March 31, 2018 and December 31, 2017, respectively	(25,485)	(11,041)
Additional paid-in capital	930,954	900,746
Retained Earnings (Accumulated deficit)	90,242	(62,129)
Accumulated other comprehensive income	4,232	2,991
Total Virtu Financial Inc. stockholders' equity	999,945	830,569
Noncontrolling interest	458,530	321,009
Total equity	1,458,475	1,151,578
Total liabilities and equity	7,757,931	7,320,006
Class A
Virtu Financial Inc. Stockholders' equity
Common stock value	1	1
Class B
Virtu Financial Inc. Stockholders' equity
Common stock value	0	0
Class C
Virtu Financial Inc. Stockholders' equity
Common stock value	0	0
Class D
Virtu Financial Inc. Stockholders' equity
Common stock value	$ 1	$ 1

Condensed Consolidated Stateme3

Condensed Consolidated Statements of Financial Condition (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Accumulated depreciation	$ 373,232	$ 375,656
Intangibles accumulated amortization	130,246	123,409
Fair value of other assets	$ 100,811	$ 98,364
Treasury stock shares	1,175,007	616,923
Class A
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	92,687,589	90,415,532
Common stock shares outstanding	91,512,582	89,798,609
Class B
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	0	0
Common stock shares outstanding	0	0
Class C
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	17,066,564	17,880,239
Common stock shares outstanding	17,066,564	17,880,239
Class D
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	79,610,490	79,610,490
Common stock shares outstanding	79,610,490	79,610,490

Condensed Consolidated Stateme4

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenues:
Trading income, net	$ 406,162	$ 139,574
Interest and dividends income	17,949	4,874
Commissions, net and technology services	53,844	2,779
Other, net	337,098	60
Total revenue	815,053	147,287
Operating Expenses:
Brokerage, exchange and clearance fees, net	87,824	52,770
Communication and data processing	49,486	18,207
Employee compensation and payroll taxes	64,670	21,347
Payments for order flow	16,256	0
Interest and dividends expense	33,624	12,280
Operations and administrative	19,919	4,846
Depreciation and amortization	15,339	6,757
Amortization of purchased intangibles and acquired capitalized software	6,851	53
Termination of office leases	19,970	0
Debt issue cost related to debt refinancing	6,021	0
Transaction advisory fees and expenses	7,496	132
Charges related to share based compensation at IPO	14	185
Financing interest expense on long-term borrowings	19,047	6,828
Total operating expenses	346,517	123,405
Income before income taxes and noncontrolling interest	468,536	23,882
Provision for income taxes	58,514	2,808
Net income	410,022	21,074
Noncontrolling interest	(235,271)	(16,494)
Net income available for common stockholders	$ 174,751	$ 4,580
Earnings per share
Basic (in dollars per share)	$ 1.89	$ 0.10
Diluted (in dollars per share)	$ 1.86	$ 0.10
Weighted average common shares outstanding
Basic (in shares)	90,699,321	40,398,381
Diluted (in shares)	92,406,318	40,398,381
Comprehensive income
Net income	$ 410,022	$ 21,074
Other comprehensive income
Foreign exchange translation adjustment, net of taxes	2,529	785
Comprehensive income	412,551	21,859
Less: Comprehensive income attributable to noncontrolling interest	(236,559)	(17,044)
Comprehensive income attributable to common stockholders	$ 175,992	$ 4,815

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Changes in Equity - 3 months ended Mar. 31, 2018 - USD ($) $ in Thousands	Total	Total Stockholders' Equity	Common StockClass A	Common StockClass C	Common StockClass D	Treasury Stock	Additional Paid-in Capital	Retained Earnings (Accumulated Deficit)	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interest
Balance end of period (in shares) at Dec. 31, 2017			90,415,532	17,880,239	79,610,490,000	616,923,000
Balance at Dec. 31, 2017	$ 1,151,578	$ 830,569	$ 1	$ 0	$ 1	$ (11,041)	$ 900,746	$ (62,129)	$ 2,991	$ 321,009
Increase (decrease) in stockholder's/members' equity
Share based compensation (in shares)			744,536
Share based compensation	16,632	16,632					16,632
Repurchase of Class C common stock (in shares)				(18,154)
Repurchase of Class C common stock	(332)	(332)					(332)
Treasury stock purchases (in shares)						(558,084,000)
Treasury stock purchases	(14,444)	(14,444)				$ (14,444)
Stock option exercised (in shares)			732,000
Stock option exercised	13,908	13,908					13,908
Net income	410,022	174,751						174,751		235,271
Foreign exchange translation adjustment	2,529	1,241							1,241	1,288
Distribution from Virtu Financial to non-controlling interest	(99,038)									(99,038)
Dividends	(22,380)	(22,380)						(22,380)
Issuance of common stock in connection with employee exchanges			795,521
Repurchase of Virtu Financial Units and corresponding number of Class C common stock in connection with employee exchanges (in shares)				(795,521)
Balance at Mar. 31, 2018	$ 1,458,475	$ 999,945	$ 1	$ 0	$ 1	$ (25,485)	$ 930,954	$ 90,242	$ 4,232	$ 458,530
Balance end of period (in shares) at Mar. 31, 2018			92,687,589	17,066,564	79,610,490,000	1,175,007,000

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities
Net Income	$ 410,022	$ 21,074
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	15,339	6,757
Amortization of purchased intangibles and acquired capitalized software	6,851	53
Debt issue cost related to debt refinancing	6,021	0
Amortization of debt issuance costs and deferred financing fees	1,583	214
Termination of office leases	19,970	0
Share based compensation	9,122	3,818
Deferred taxes	2,471	2,354
Gain on sale of BondPoint	(329,703)	0
Other	(7,328)	1,570
Changes in operating assets and liabilities:
Securities borrowed	239,124	(138,458)
Securities purchased under agreements to resell	(602)	0
Receivables from broker dealers and clearing organizations	(462,022)	(213,585)
Trading assets, at fair value	(194,984)	(72,088)
Other Assets	5,848	563
Securities loaned	181,374	201,469
Securities sold under agreements to repurchase	(125,241)	0
Payables to broker dealers and clearing organizations	(67,417)	(106,290)
Trading liabilities, at fair value	461,855	324,647
Accounts payable and accrued expenses and other liabilities	(53,276)	(11)
Net cash provided by operating activities	119,007	32,087
Cash flows from investing activities
Development of capitalized software	(7,016)	(2,016)
Acquisition of property and equipment	(4,505)	(3,843)
Proceeds from sale of BondPoint	400,192	0
Net cash provided by (used in) investing activities	388,671	(5,859)
Cash flows from financing activities
Distribution from Virtu Financial to non-controlling interest	(99,038)	(21,011)
Dividends	(22,380)	(10,114)
Purchase of treasury stock	(14,444)	(441)
Stock option exercised	13,908	0
Short-term borrowings, net	(7,500)	(3,000)
Payments on repurchase of non-voting common interest	0	(500)
Repayment of senior secured credit facility	(276,000)	(1,350)
Tax receivable agreement obligations	0	(7,045)
Debt issuance costs	0	0
Net cash used in financing activities	(405,786)	(43,461)
Effect of exchange rate changes on cash and cash equivalents	2,529	785
Net increase in cash and cash equivalents	104,421	(16,448)
Cash and cash equivalents beginning of period	532,887	181,415
Cash and cash equivalents, end of period	637,308	164,967
Supplementary disclosure of cash flow information
Cash paid for interest	30,632	13,197
Cash paid for taxes	156	1,915
Non-cash investing activities
Share based compensation to developers relating to capitalized software	206	664
Class C
Cash flows from financing activities
Purchase of treasury stock	$ (332)	$ 0

Organization and Basis of Prese

Organization and Basis of Presentation	3 Months Ended
	Mar. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Basis of Presentation	Organization and Basis of Presentation Organization The accompanying consolidated financial statements include the accounts and operations of Virtu Financial, Inc. (“VFI” or, collectively with its wholly owned or controlled subsidiaries, the “Company”) beginning with its initial public offering (“IPO”) in April of 2015, along with the historical accounts and operations of Virtu Financial LLC (“Virtu Financial”) prior to the Company’s IPO. VFI is a Delaware corporation whose primary asset is its ownership interest in Virtu Financial, which it acquired pursuant to and subsequent to certain reorganization transactions (the “Reorganization Transactions”) consummated in connection with its IPO. As of March 31, 2018 , VFI owned approximately 49.1% of the membership interests of Virtu Financial. VFI is the sole managing member of Virtu Financial and operates and controls all of the businesses and affairs of Virtu Financial and, through Virtu Financial and its subsidiaries (the “Group”), continues to conduct the business now conducted by such subsidiaries. The Company is a leading financial firm that leverages cutting edge technology to deliver liquidity to the global markets and innovative, transparent trading solutions to its clients. The Company has broad diversification, in combination with its proprietary technology platform and low-cost structure, which enables the Company to facilitate risk transfer between global capital markets participants by supplying competitive liquidity and execution services while at the same time earning attractive margins and returns. On July 20, 2017 (the “Closing Date”), the Company completed the all-cash acquisition (the “Acquisition”) of KCG Holdings, Inc. (“KCG”). Pursuant to the terms of the Agreement and Plan of Merger, dated as of April 20, 2017 (the “Merger Agreement”), by and among the Company, Orchestra Merger Sub, Inc., a Delaware corporation and an indirect wholly-owned subsidiary of the Company (“Merger Sub”), and KCG Merger Sub merged with and into KCG (the “Merger”), with KCG surviving the Merger as a wholly owned subsidiary of the Company. See Note 3 “Acquisition of KCG Holdings Inc.” for further details. Virtu Financial’s principal subsidiaries include Virtu Financial BD LLC (“VFBD”) and Virtu Americas LLC (“VAL”), which are self-clearing U.S. broker-dealers, Virtu Financial Capital Markets LLC (“VFCM”), a U.S. broker-dealer, which self-clears its proprietary transactions and introduces the accounts of its affiliates and non-affiliated broker-dealers on an agency basis to other clearing firms that clear and settle transactions in those accounts. Other principal subsidiaries include Virtu Financial Global Markets LLC (“VFGM”), a U.S. trading entity focused on futures and currencies; Virtu Financial Ireland Limited (“VFIL”), formed in Ireland; Virtu Financial Asia Pty Ltd (“VFAP”), formed in Australia; and Virtu Financial Singapore Pte. Ltd. (“VFSing”), formed in Singapore, each of which are trading entities focused on asset classes in their respective geographic regions. On January 2, 2018, the Company completed the sale of its fixed income trading venue, BondPoint, to Intercontinental Exchange (“ICE”) for total gross proceeds of $400.2 million . See Note 4 “Sale of BondPoint” for further details. Prior to the Acquisition of KCG, the Company was managed and operated as one business, under one reportable segment. As a result of the Acquisition of KCG, beginning in the third quarter of 2017 the Company has three operating segments: (i) Market Making; (ii) Execution Services; and (iii) Corporate. See Note 19 "Geographic information and business segments" for a further discussion of the Company’s segments. Basis of Consolidation and Form of Presentation These condensed consolidated financial statements are presented in U.S. dollars and have been prepared pursuant to the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) regarding financial reporting with respect to Form 10-Q and accounting standards generally accepted in the United States of America (“U.S. GAAP”) promulgated in the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC” or the “Codification”). The condensed consolidated financial statements of the Company include its equity interests in Virtu Financial, and its subsidiaries. The Company operates and controls all business and affairs of Virtu Financial and its operating subsidiaries indirectly through its equity interest in Virtu Financial. Certain reclassifications have been made to the prior periods’ condensed consolidated financial statements in order to conform to the current period presentation. Such reclassifications are immaterial, individually and in the aggregate, to both current and all previously issued financial statements taken as a whole and have no effect on previously reported condensed consolidated net income available to common stockholders. The condensed consolidated financial statements include the accounts of the Company and its majority and wholly owned subsidiaries. As sole managing member of Virtu Financial, the Company exerts control over the Group’s operations. The Company consolidates Virtu Financial and its subsidiaries’ financial statements and records the interests in Virtu Financial that the Company does not own as noncontrolling interests. All intercompany accounts and transactions have been eliminated in consolidation. As discussed in Note 3 “Acquisition of KCG Holdings Inc.”, the Company has accounted for the acquisition of KCG under the acquisition method of accounting. Under the acquisition method of accounting, the assets and liabilities of KCG, as of July 20, 2017, were recorded at their respective fair values and added to the carrying value of the Company's existing assets and liabilities. The reported financial condition, results of operations and cash flows of the Company for the periods following the Acquisition reflect KCG's and the Company's balances, and reflect the impact of purchase accounting adjustments. The financial results for the three months ended March 31, 2017 comprise solely the results of the Company.

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2018
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Use of Estimates The Company's condensed consolidated financial statements are prepared in conformity with U.S. GAAP, which require management to make estimates and assumptions regarding measurements including the fair value of trading assets and liabilities, goodwill and intangibles, compensation accruals, capitalized software, income tax, and other matters that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. Accordingly, actual results could differ materially from those estimates. Earnings Per Share Earnings per share (“EPS”) is calculated on both a basic and diluted basis. Basic EPS excludes dilution and is calculated by dividing income available to common stockholders by the weighted-average number of common shares outstanding for the period. Diluted EPS is calculated by dividing the net income available for common stockholders by the diluted weighted average shares outstanding for that period. Diluted EPS includes the determinants of the basic EPS and, in addition, reflects the dilutive effect of shares of common stock estimated to be distributed in the future under the Company’s share based compensation plans. The Company grants restricted stock units (“RSUs”), which entitle recipients to receive nonforfeitable dividends during the vesting period on a basis equivalent to the dividends paid to holders of common stock. As a result, the unvested RSUs meet the definition of a participating security requiring the application of the two-class method. Under the two-class method, earnings available to common shareholders, including both distributed and undistributed earnings, are allocated to each class of common stock and participating securities according to dividends declared and participating rights in undistributed earnings, which may cause diluted EPS to be more dilutive than the calculation using the treasury stock method. Cash and Cash Equivalents Cash and cash equivalents include money market accounts, which are payable on demand, and short-term investments with an original maturity of less than 90 days. The Company maintains cash in bank deposit accounts that, at times, may exceed federally insured limits. The Company manages this risk by selecting financial institutions deemed highly creditworthy to minimize the risk. Securities Borrowed and Securities Loaned The Company conducts securities borrowing and lending activities with external counterparties. In connection with these transactions, the Company receives or posts collateral, which comprises cash and/or securities. In accordance with substantially all of its stock borrow agreements, the Company is permitted to sell or repledge the securities received. Securities borrowed or loaned are recorded based on the amount of cash collateral advanced or received. The initial cash collateral advanced or received generally approximates or is greater than 102% of the fair value of the underlying securities borrowed or loaned. The Company monitors the fair value of securities borrowed and loaned, and delivers or obtains additional collateral as appropriate. Receivables and payables with the same counterparty are not offset in the condensed consolidated statements of financial condition. Interest received or paid by the Company for these transactions is recorded gross on an accrual basis under interest and dividends income or interest and dividends expense in the condensed consolidated statements of comprehensive income. Securities Purchased Under Agreements to Resell and Securities Sold Under Agreements to Repurchase In a repurchase agreement, securities sold under agreements to repurchase are treated as collateralized financing transactions and are recorded at contract value, plus accrued interest, which approximates fair value. It is the Company's policy that its custodian takes possession of the underlying collateral securities with a fair value approximately equal to the principal amount of the repurchase transaction, including accrued interest. For reverse repurchase agreements, the Company typically requires delivery of collateral with a fair value approximately equal to the carrying value of the relevant assets in the condensed consolidated statements of financial condition. To ensure that the fair value of the underlying collateral remains sufficient, the collateral is valued daily with additional collateral obtained or excess collateral returned, as permitted under contractual provisions. The Company does not net securities purchased under agreements to resell transactions with securities sold under agreements to repurchase transactions entered into with the same counterparty. The Company has also entered into bilateral and tri-party term and overnight repurchase and other collateralized financing agreements which bear interest at negotiated rates. The Company receives cash and makes delivery of financial instruments to a custodian who monitors the market value of these instruments on a daily basis. The market value of the instruments delivered must be equal to or in excess of the principal amount loaned under the repurchase agreements plus the agreed upon margin requirement. The custodian may request additional collateral, if appropriate. Interest received or paid by the Company for these transactions is recorded gross on an accrual basis under interest and dividends income or interest and dividends expense in the condensed consolidated statements of comprehensive income. Receivables from/Payables to Broker-dealers and Clearing Organizations Amounts receivable from broker-dealers and clearing organizations may be restricted to the extent that they serve as deposits for securities sold, not yet purchased. At March 31, 2018 and December 31, 2017 , receivables from and payables to broker-dealers and clearing organizations primarily represented amounts due for unsettled trades, open equity in futures transactions, securities failed to deliver or failed to receive, deposits with clearing organizations or exchanges and balances due from or due to prime brokers in relation to the Company’s trading. The Company presents its balances, including outstanding principal balances on all credit facilities, on a net by counterparty basis within receivables from and payable to broker-dealers and clearing organizations when the criteria for offsetting are met. In the normal course of business, a significant portion of the Company’s securities transactions, money balances, and security positions are transacted with several third-party brokers. The Company is subject to credit risk to the extent any broker with whom it conducts business is unable to fulfill contractual obligations on its behalf. The Company monitors the financial condition of such brokers and to minimize the risk of any losses from these counterparties. Financial Instruments Owned Including Those Pledged as Collateral and Financial Instruments Sold, Not Yet Purchased Financial instruments owned and Financial instruments sold, not yet purchased relate to market making and trading activities, and include listed and other equity securities, listed equity options and fixed income securities. The Company records financial instruments owned, including those pledged as collateral, and financial instruments sold, not yet purchased at fair value. Gains and losses arising from financial instrument transactions are recorded net on a trade-date basis in trading income, net, in the condensed consolidated statements of comprehensive income. Fair Value Measurements Fair value is defined as the price that would be received to sell an asset or would be paid to transfer a liability (i.e., the exit price) in an orderly transaction between market participants at the measurement date. Fair value measurements are not adjusted for transaction costs. The recognition of “block discounts” for large holdings of unrestricted financial instruments where quoted prices are readily and regularly available in an active market is prohibited. The Company categorizes its financial instruments into a three level hierarchy which prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy level assigned to each financial instrument is based on the assessment of the transparency and reliability of the inputs used in the valuation of such financial instruments at the measurement date based on the lowest level of input that is significant to the fair value measurement. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (level 1 measurement) and the lowest priority to unobservable inputs (level 3 measurements). Financial instruments measured and reported at fair value are classified and disclosed in one of the following categories based on inputs: Level 1 — Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities; Level 2 — Quoted prices in markets that are not active and financial instruments for which all significant inputs are observable, either directly or indirectly; or Level 3 — Prices or valuations that require inputs that are both significant to the fair value measurement and unobservable. Transfers in or out of levels are recognized based on the beginning fair value of the period in which they occurred. Fair Value Option The fair value option election allows entities to make an irrevocable election of fair value as the initial and subsequent measurement attribute for certain eligible financial assets and liabilities. Unrealized gains and losses on items for which the fair value option has been elected are recorded in other, net in the condensed consolidated statements of comprehensive income. The decision to elect the fair value option is determined on an instrument by instrument basis, which must be applied to an entire instrument and is irrevocable once elected. Derivative Instruments Derivative instruments are used for trading purposes, including economic hedges of trading instruments, which are carried at fair value include futures, forward contracts, and options. Gains or losses on these derivative instruments are recognized currently within trading income, net in the condensed consolidated statement of comprehensive income. Fair values for exchange-traded derivatives, principally futures, are based on quoted market prices. Fair values for over-the-counter derivative instruments, principally forward contracts, are based on the values of the underlying financial instruments within the contract. The underlying instruments are currencies, which are actively traded. The Company presents its derivatives balances on a net-by-counterparty basis when the criteria for offsetting are met. Property, Equipment and Occupancy Property and equipment are carried at cost, less accumulated depreciation, except for the assets acquired in connection with acquisitions using the purchase accounting method, which were recorded at fair value on the respective date of acquisitions. Depreciation is provided using the straight-line method over estimated useful lives of the underlying assets. Routine maintenance, repairs and replacement costs are expensed as incurred and improvements that appreciably extend the useful life of the assets are capitalized. When property and equipment are sold or otherwise disposed of, the cost and related accumulated depreciation are removed from the accounts and any resulting gain or loss is recognized in income. Property and equipment are reviewed for impairment whenever events or changes in circumstances indicate that the related carrying amount may not be recoverable. Furniture, fixtures, and equipment are depreciated over three to seven years. Leasehold improvements are amortized over the lesser of the life of the improvement or the term of the lease. The Company recognizes rent expense under operating leases with fixed rent escalations, lease incentives and free rent periods on a straight-line basis over the lease term beginning on the date the Company takes possession of or controls the use of the space, including during free rent periods. Lease Loss Accrual The Company’s policy is to identify excess real estate capacity and where applicable, accrue for related future costs, net of projected sub-lease income upon the date the Company ceases to use the excess real estate, which is recorded under operating and administrative in the condensed consolidated statements of comprehensive income. Such accrual is adjusted to the extent the actual terms of sub-leased property differ from the previous assumptions used in the calculation of the accrual. Capitalized Software The Company capitalizes costs of materials, consultants, and payroll and payroll related costs for employees incurred in developing internal-use software. Costs incurred during the preliminary project and post-implementation stages are charged to expense. Management’s judgment is required in determining the point at which various projects enter the stages at which costs may be capitalized, in assessing the ongoing value of the capitalized costs, and in determining the estimated useful lives over which the costs are amortized. Capitalized software development costs and related accumulated amortization are included in property, equipment and capitalized software in the accompanying condensed consolidated statements of financial condition and are amortized over a period of 1.5 to 2.5 years , which represents the estimated useful lives of the underlying software. Goodwill Goodwill represents the excess of the purchase price over the underlying net tangible and intangible assets of the Company’s acquisitions. Goodwill is not amortized but is tested for impairment on an annual basis and between annual tests whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. Goodwill is tested at the reporting unit level, which is defined as an operating segment or one level below the operating segment. The Company tests goodwill for impairment on an annual basis on July 1 and on an interim basis when certain events or circumstances exist. In the impairment test as of July 1, 2017, the primary valuation method used to estimate the fair value of the Company’s reporting unit was the market capitalization approach based on the market price of its Class A common stock, which the Company’s management believes to be an appropriate indicator of its fair value. Following the Acquisition, our impairment testing is performed for each reporting unit. Intangible Assets The Company amortizes finite-lived intangible assets over their estimated useful lives. Finite-lived intangible assets are tested for impairment annually or when impairment indicators are present, and if impaired, they are written down to fair value. Exchange Memberships and Stock Exchange memberships are recorded at cost or, if any other than temporary impairment in value has occurred, at a value that reflects management’s estimate of fair value. Exchange memberships acquired in connection with the Acquisition were recorded at their fair value on the date of acquisition. Exchange stock includes shares that entitle the Company to certain trading privileges. The Company’s exchange memberships and stock are included in intangibles in the condensed consolidated statements of financial condition. Trading Income, net Trading income, net is comprised of changes in the fair value of trading assets and liabilities (i.e., unrealized gains and losses) and realized gains and losses on trading assets and liabilities. Trading gains and losses on financial instruments owned and financial instruments sold, not yet purchased are recorded on the trade date and reported on a net basis in the condensed consolidated statements of comprehensive income. The Company recognizes the related revenue when the third party research services are rendered and payments are made. Commissions, net and Technology Services Commissions, net, which primarily comprise commissions and commission equivalents earned on institutional client orders, are recorded on a trade date basis. Under a commission management program, the Company allows institutional clients to allocate a portion of their gross commissions to pay for research and other services provided by third parties. As the Company acts as an agent in these transactions, it records such expenses on a net basis within Commissions and technology services in the condensed consolidated statements of comprehensive income. Technology services revenues consist of technology licensing fees and agency commission fees. Technology licensing fees are earned from third parties for licensing of the Company’s proprietary risk management and trading infrastructure technology and the provision of associated management and hosting services. These fees include both upfront and annual recurring fees, as well as, in certain cases, contingent fees based on client revenues, which represent variable consideration. The services offered under these contracts have the same pattern of transfer; accordingly, they are being measured and recognized as a single performance obligation. The performance obligation is satisfied over time, and accordingly, revenue is recognized as time passes. Variable consideration has not been included in the transaction price as the amount of consideration is contingent on factors outside the Company’s control and thus it is not probable that a significant reversal of cumulative revenue recognized will not occur. Recurring fees, which exclude variable consideration, are billed and collected on a quarterly basis. Interest and Dividends Income/Interest and Dividends Expense Interest income and interest expense are accrued in accordance with contractual rates. Interest income consists of interest earned on collateralized financing arrangements and on cash held by brokers. Interest expense includes interest expense from collateralized transactions, margin and related lines of credit. Dividends on financial instruments owned including those pledged as collateral and financial instruments sold, not yet purchased are recorded on the ex-dividend date and interest is recognized on an accrual basis. Brokerage, Exchange and Clearance Fees, Net Brokerage, exchange and clearance fees, net, comprise the costs of executing and clearing trades and are recorded on a trade date basis. Rebates consist of volume discounts, credits or payments received from exchanges or other market places related to the placement and/or removal of liquidity from the order flow in the marketplace. Rebates are recorded on an accrual basis and included net within brokerage, exchange and clearance fees in the accompanying condensed consolidated statements of comprehensive income. Payments for Order Flow Payments for order flow represent payments to broker-dealer clients, in the normal course of business, for directing their order flow in U.S. equities to the Company. Payments for order flow are recorded on a trade-date basis in the condensed consolidated statements of comprehensive income. Income Taxes Subsequent to consummation of the Reorganization Transactions and the IPO, the Company is subject to U.S. federal, state and local income taxes on its taxable income. The Company's subsidiaries are subject to income taxes in the respective jurisdictions (including foreign jurisdictions) in which they operate. Prior to the consummation of the Reorganization Transactions and the IPO, no provision for United States federal, state and local income tax was required, as Virtu Financial is a limited liability company and is treated as a pass-through entity for United States federal, state, and local income tax purposes. The provision for income tax is comprised of current tax and deferred tax. Current tax represents the tax on current year tax returns, using tax rates enacted at the balance sheet date. The deferred tax assets are recognized in full and then reduced by a valuation allowance if it is more likely than not that some or all of the deferred tax assets will not be recognized. The Company recognizes the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained on examination by the applicable taxing authority, including resolution of the appeals or litigation processes, based on the technical merits of the position. The tax benefits recognized in the condensed consolidated financial statements from such a position are measured based on the largest benefit for each such position that has a greater than fifty percent likelihood of being realized upon ultimate resolution. Many factors are considered when evaluating and estimating the tax positions and tax benefits. Such estimates involve interpretations of regulations, rulings, case law, etc. and are inherently complex. The Company’s estimates may require periodic adjustments and may not accurately anticipate actual outcomes as resolution of income tax treatments in individual jurisdictions typically would not be known for several years after completion of any fiscal year. Public Law No. 115-97, commonly referred to as The Tax Cuts and Jobs Act (the “2017 Tax Act”) was signed into law on December 22, 2017. The 2017 Tax Act significantly changes how the U.S. federal government taxes corporations and requires significant judgments to be made in interpretation of its provisions and significant estimates in calculations, and the preparation and analysis of information not previously relevant or regularly produced. The U.S. Treasury Department, the IRS, and other standard-setting bodies could interpret or issue guidance on how provisions of the 2017 Tax Act will be applied or otherwise administered that is different from our interpretation. As we complete our analysis of the 2017 Tax Act, collect and prepare necessary data, and interpret any additional guidance, we may make adjustments to provisional amounts that we have recorded that may materially impact our provision for income taxes in the period in which the adjustments are made. See Note 14 “Income Taxes”. Comprehensive Income and Foreign Currency Translation Comprehensive income consists of two components: net income and other comprehensive income (“OCI”). The Company’s OCI is comprised of foreign currency translation adjustments. Assets and liabilities of operations having non-U.S. dollar functional currencies are translated at period-end exchange rates, and revenues and expenses are translated at weighted average exchange rates for the period. Gains and losses resulting from translating foreign currency financial statements, net of related tax effects, are reflected in accumulated other comprehensive income, a separate component of stockholders’ equity. The Company's foreign subsidiaries generally use the U.S. dollar as their functional currency. The Company also has subsidiaries that utilize a functional currency other than the U.S. dollar, primarily comprising its subsidiaries domiciled in Ireland, which utilizes the Euro as the functional currency. The Company may seek to reduce the impact of fluctuations in foreign exchange rates on its net investment in certain non-U.S. operations through the use of foreign currency forward contracts. For foreign currency forward contracts designated as hedges, the Company assesses its risk management objectives and strategy, including identification of the hedging instrument, the hedged item and the risk exposure and how effectiveness is to be assessed prospectively and retrospectively. The effectiveness of the hedge is assessed based on the overall changes in the fair value of the forward contracts. For qualifying net investment hedges, any gains or losses, to the extent effective, are included in Accumulated other comprehensive income on the condensed consolidated statements of financial condition and Cumulative translation adjustment, net of tax, on the condensed consolidated statements of comprehensive income. The ineffective portion, if any, is recorded in Investment income and other, net on the condensed consolidated statements of operations. Share-Based Compensation The fair value of awards issued for compensation prior to the Reorganization Transactions and the IPO was determined by management, with the assistance of an independent third party valuation firm, using a projected annual forfeiture rate, where applicable, on the date of grant. Share-based awards issued for compensation in connection with or subsequent to the Reorganization Transactions and the IPO pursuant to the VFI 2015 Management Incentive Plan (as amended, the “2015 Amended and Restated Management Incentive Plan”) were in the form of stock options, Class A common stock and RSUs. The fair value of the stock option grants is determined through the application of the Black-Scholes-Merton model. The fair value of the Class A common stock and RSUs are determined based on the volume weighted average price for the three days preceding the grant, and with respect to the RSUs, a projected annual forfeiture rate. The fair value of share-based awards granted to employees is expensed based on the vesting conditions and are recognized on a straight line basis over the vesting period. The Company records as treasury stock shares repurchased from its employees for the purpose of settling tax liabilities incurred upon the issuance of Class A common stock, the vesting of RSUs or the exercise of stock options. Variable Interest Entities A variable interest entity (“VIE”) is an entity that lacks one or more of the following characteristics (i) the total equity investment at risk is sufficient to enable the entity to finance its activities independently and (ii) the equity holders have the power to direct the activities of the entity that most significantly impact its economic performance, the obligation to absorb the losses of the entity and the right to receive the residual returns of the entity. The Company will be considered to have a controlling financial interest and will consolidate a VIE if it has both (i) the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance and (ii) the obligation to absorb losses of the VIE or the right to receive benefits from the VIE that could potentially be significant to the VIE. In October 2016, the Company invested in a joint venture (“JV”) with nine other parties. One of the parties was KCG. Upon the Merger, KCG was required to relinquish their ownership in the JV. As of March 31, 2018 , each of the remaining parties owns approximately 11% of the voting shares and 11% of the equity of this JV, which is building microwave communication networks in the U.S. and Asia, and which is considered to be a VIE. The Company and all of its JV partners each pay monthly fees for the funding of the construction of the microwave communication networks. When completed, this JV may sell excess bandwidth that is not utilized by its joint venture members to third parties. In addition, as a result of the Acquisition, the Company owns 50% of the voting shares and 50% of the equity of a JV which maintains microwave communication networks in the U.S. and Europe, and which is considered to be a VIE. The Company and its JV partner each pay monthly fees for the use of the microwave communication networks in connection with their respective trading activities, and the JV may sell excess bandwidth that is not utilized by the JV members to third parties. In each of the JVs, the Company does not have the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance; therefore it does not have a controlling financial interest in the JV and does not consolidate the JVs. The Company records its interest in each JV under the equity method of accounting and records its investment in the JVs within Other assets and its amounts payable for communication services provided by the JV within Accrued expenses and other liabilities on the condensed consolidated statements of financial condition. The Company records its pro-rata share of each JVs earnings or losses within Other, net and fees related to the use of communication services provided by the JVs within Communications and data processing on the condensed consolidated statements of comprehensive income. The Company’s exposure to the obligations of these VIEs is generally limited to its interests in each respective JV, which is the carrying value of the equity investment in each JV. The following table presents the Company’s nonconsolidated VIE at March 31, 2018 : Carrying Amount Maximum Exposure to loss VIE's assets (in thousands) Asset Liability Equity investment $ 18,472 $ — $ 18,472 $ 51,344 The following table presents the Company’s nonconsolidated VIE at December 31, 2017 : Carrying Amount Maximum Exposure to VIE's assets (in thousands) Asset Liability Equity investment $ 18,799 $ — $ 18,799 $ 41,936 Recent Accounting Pronouncements Revenue - In May 2014, the FASB issued Accounting Standard Update (“ASU”) 2014-9, Revenue from Contracts with Customers . ASU 2014-9 is a comprehensive new revenue recognition model that requires a company to recognize revenue to depict the transfer of goods or services to a customer at an amount that reflects the consideration it expects to receive in exchange for those goods or services. ASU 2014-9 also requires additional disclosure about the nature, amount, timing and uncertainty of revenue and cash flows arising from customer contracts, including significant judgments and changes in judgments and assets recognized from costs incurred to obtain or fulfill a contract. In August 2015, the FASB issued ASU 2015-14, Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date . ASU 2015-14 defers the effective date of ASU 2014-9 by one year for public companies. ASU 2015-14 applies to annual reporting periods beginning after December 15, 2017, including interim reporting periods within that reporting period. In December 2016, FASB issued ASU 2016-20T echnical Correction and Improvement (Topic 606): Revenue from Contracts with Customers , which amends the guidance in ASU 2014-9. The effective date and transition requirements for the ASU are the same as ASU 2015-14. The Company adopted the new revenue standard on January 1, 2018 by applying the modified retrospective method, which did not result in a transition adjustment. The new standard does not apply to revenue associated with financial instruments that are accounted for under other U.S. GAAP, and as a result, did not have an impact on the Company’s condensed consolidated statements of comprehensive income, which are most closely associated with financial instruments, including trading income, net, and interest and dividends income. The new revenue standard primarily impacts revenues from technology services, commissions and soft-dollar arrangements generated by execution services. The additional disclosures required by the new standard have been included in Note 13 "Revenues from contracts with customers" . Financial Assets and Liabilities — In January 2016, the FASB issued ASU 2016-01, Financial Instruments – Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities . The ASU affects the accounting for equity investments, financial liabilities under fair value option and presentation and disclosure requirements of financial instruments. The new ASU affects all entities that hold financial assets or owe financial liabilities and is effective for annual reporting periods (including interim periods) beginning after December 15, 2017. The Company does not currently classify any equity securities as available for sale, and it does not apply the fair value option to its own debt issuances. The Company has adopted this ASU as of March 31, 2018, and it did not have a material impact on its condensed consolidated financial statements. Leases — In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) . Under the new ASU, a lessee will be required to recognize assets and liabilities for leases with lease terms of more than 12 months. The liability will be equal to the present value of the future lease payments. The asset, referred to as a “right-of-use asset” will be based on the liability, subject to adjustment, such as for initial direct costs. For income statement pu

Acquisition of KCG Holdings, In

Acquisition of KCG Holdings, Inc.	3 Months Ended
	Mar. 31, 2018
Business Combinations [Abstract]
Acquisition of KCG Holdings, Inc.	Acquisition of KCG Holdings, Inc. As of the Closing Date of the Acquisition, each of KCG’s issued and outstanding shares of Class A common stock, par value $0.01 per share was cancelled and extinguished and converted into the right to receive $20.00 in cash, without interest, less any applicable withholding taxes. On the Closing Date, and in connection with the financing of the Acquisition, as described in Note 10 "Borrowings" , the Company issued to Aranda Investments Pte. Ltd. (“Aranda”), an affiliate of Temasek Holdings (Private) Limited (“Temasek”), 6,346,155 shares of the Company’s Class A common stock, pursuant to the investment agreement with Aranda (as amended, the “Aranda Investment Agreement”) for an aggregate purchase price of approximately $99.0 million . On August 10, 2017, the Company issued an additional 1,666,666 shares of its Class A common stock for an aggregate purchase price of $26.0 million (collectively, the “Temasek Investment”). On the Closing Date, and in connection with the financing of the Acquisition, the Company issued to North Island Holdings I, LP (“NIH”) 39,725,979 shares of the Company’s Class A common stock for an aggregate purchase price of approximately $613.5 million . On August 10, 2017 the Company issued an additional 338,124 shares of its Class A common stock for an aggregate purchase price of $5.2 million (collectively, the “NIH Investment”). In connection with the Temasek Investment and NIH Investment, the Company incurred approximately $7.8 million in fees which were recorded as a reduction to additional paid-in capital. On July 21, 2017, the outstanding 6.875% Senior Secured Notes due 2020 issued by KCG were redeemed at a redemption price equal to 103.438% of the $465.0 million principal amount, plus accrued and unpaid interest. The redemption was pursuant to the indenture, dated as of March 13, 2015 (as amended, restated, supplemented or otherwise modified), by and among KCG, the subsidiary guarantors party thereto and The Bank of New York Mellon, as trustee and collateral agent. See "Fourth Amended and Restated Credit Agreement" and "Senior Secured Second Lien Notes" in Note 10 "Borrowings" . Accounting treatment of the Acquisition The Acquisition is accounted for as a purchase of KCG by the Company, pursuant to provisions of ASC 805, Business Combinations . Under the acquisition method of accounting, the assets and liabilities of KCG, as of July 20, 2017, were recorded at their respective fair values and added to the carrying value of the Company's existing assets and liabilities. These fair values were determined with the assistance of third party valuation professionals. The reported financial condition, results of operations and cash flows of the Company for the periods following the Acquisition reflect KCG’s and the Company's balances and reflect the impact of purchase accounting adjustments. Purchase price and goodwill The aggregate cash purchase price of $1.4 billion was determined as the sum of the fair value, at $20.00 per share, of KCG shares and warrants outstanding to former KCG stockholders at closing and the fair value of KCG employee stock based awards that were outstanding, and which vested at the Closing Date. The purchase price has been allocated to the assets acquired and liabilities assumed using their estimated fair values at the Closing Date of the Acquisition. Although the Company has substantially completed its analysis to record the allocation of the purchase price to the KCG acquired assets and liabilities, the allocation of the purchase price may be modified over the measurement period, which does not exceed twelve months from the Closing Date, as more information is obtained about the fair values of assets acquired and liabilities assumed. Adjustments to the provisional values during the measurement period will be recorded in the reporting period in which the adjustment amounts are determined. The Company has engaged third party specialists for the purchase price allocation. Amounts allocated to intangible assets, the amortization period and goodwill were as follows: (in thousands) Amount Amortization Years Technology $ 67,700 1-6 years Customer relationships 94,000 13 - 17 years Trade names 1,000 10 years Favorable leases 5,895 2-15 years Exchange memberships 6,400 Indefinite Intangible assets $ 174,995 Goodwill 128,286 Total $ 303,281 Of the total Goodwill of $128.3 million , $96.2 million has been assigned to the Market Making segment and $32.1 million has been assigned to the Execution Services segment. Such goodwill is attributable to the expansion of products offerings and expected synergies of the combined workforce, products and technologies of the Company and KCG. Tax treatment of the Acquisition The Company believes that the Acquisition will be treated as a tax-free transaction to the Company that does not result in a step up in tax basis in the acquired assets and, therefore, KCG’s tax basis in its assets and liabilities generally carries over to the Company following the Acquisition. None of the goodwill is expected to be deductible for tax purposes. The Company recorded net deferred tax assets of $23.9 million with respect to recording KCG’s assets and liabilities under the purchase method of accounting as described above as well as recording the value of other tax attributes acquired as a result of the Acquisition, as described in Note 13 "Revenues from contracts with customers" .

Sale of BondPoint

Sale of BondPoint	3 Months Ended
	Mar. 31, 2018
Discontinued Operations and Disposal Groups [Abstract]
Sale of BondPoint	Sale of BondPoint In October 2017, the Company entered into an Asset Purchase Agreement (the “BondPoint Agreement”) with ICE pursuant to which the Company has agreed to sell specified assets and to assign specified liabilities constituting its BondPoint division and fixed income venue (“BondPoint”). BondPoint is a provider of electronic fixed income trading solutions for the buy-side and sell-side offering access to centralized liquidity and automated trade execution services. As of December 31, 2017, the Company transferred the carrying value of BondPoint to assets held for sale, refer to Note 4 “Business held for sale” in the Company's Annual Report on Form 10-K, filed with the Securities and Exchange Commission on March 13, 2018 (the "2017 Form 10-K"). On January 2, 2018, the Company completed the sale of BondPoint to Intercontinental Exchange for total gross proceeds of $400.2 million in cash. The Company incurred one-time transaction costs of $8.5 million , which include professional fees of $7.1 million related to the sale and $1.4 million compensation expense, which is recorded in Transaction advisory fees and expenses and Employee compensation and payroll taxes , respectively, on the condensed consolidated statement of comprehensive income. The Company recognized a gain on sale of $329.0 million , which is recorded in other, net on the condensed consolidated statement of comprehensive income for the three months ended March 31, 2018 . A summary of the carrying value of BondPoint and gain on sale of BondPoint is as follows: (in thousand) Total sale proceeds received $ 400,192 Business assets and liabilities held for sale as of December 31, 2017: Receivables from broker dealers and clearing organizations 3,383 Intangibles and other assets 51,687 Liabilities (728 ) Total carrying value of BondPoint as of December 31, 2017: 54,342 Goodwill adjustment allocated to BondPoint 8,300 Gain on sale of BondPoint 337,550 Transaction costs 8,568 Gain on sale of BondPoint, net of transaction costs $ 328,982

Earnings per Share

Earnings per Share	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
Earnings per share	Earnings per Share The below table contains a reconciliation of net income before noncontrolling interest to net income available for common stockholders: Three Months Ended March 31, (in thousands) 2018 2017 Income before income taxes and noncontrolling interest $ 468,536 $ 23,882 Provision for income taxes 58,514 2,808 Net income 410,022 21,074 Noncontrolling interest (235,271 ) (16,494 ) Net income available for common stockholders $ 174,751 $ 4,580 The calculation of basic and diluted earnings per share is presented below: Three Months Ended March 31, (in thousands, except for share or per share data) 2018 2017 Basic earnings per share: Net income available for common stockholders $ 174,751 $ 4,580 Less: Dividends and undistributed earnings allocated to participating securities (3,213 ) (353 ) Net income available for common stockholders, net of dividends and undistributed earnings allocated to participating securities 171,538 4,227 Weighted average shares of common stock outstanding: Class A 90,699,321 40,398,381 Basic Earnings per share $ 1.89 $ 0.10 Three Months Ended March 31, (in thousands, except for share or per share data) 2018 2017 Diluted earnings per share: Net income available for common stockholders, net of dividends and undistributed earnings allocated to participating securities $ 171,538 $ 4,227 Weighted average shares of common stock outstanding: Class A Issued and outstanding 90,699,321 40,398,381 Issuable pursuant to 2015 Management Incentive Plan(1) 1,706,996 — 92,406,317 40,398,381 Diluted Earnings per share $ 1.86 $ 0.10 (1) The dilutive impact of unexercised stock options excludes from the computation of EPS 774,529 options for the three months ended March 31, 2017 , because inclusion of the options would have been anti-dilutive.

Tax Receivable Agreements

Tax Receivable Agreements	3 Months Ended
	Mar. 31, 2018
Tax Receivable Agreements [Abstract]
Tax Receivable Agreements	Tax Receivable Agreements In connection with the IPO and the Reorganization Transactions, the Company entered into tax receivable agreements to make payments to certain Virtu pre-IPO equityholders ("Virtu Members"), that are generally equal to 85% of the applicable cash tax savings, if any, that the Company actually realizes as a result of favorable tax attributes that were and will continue to be available to the Company as a result of the Reorganization Transactions, exchanges of membership interests for Class A common stock or Class B common stock and payments made under the tax receivable agreements. Payments will occur only after the filing of the U.S. federal and state income tax returns and realization of the cash tax savings from the favorable tax attributes. The Company made its first payment of $7.0 million in February 2017. As a result of (i) the purchase of equity interests in Virtu Financial from certain Virtu Members in connection with the Reorganization Transactions, (ii) the purchase of non-voting common interest units in Virtu Financial (the “Virtu Financial Units”) (along with the corresponding shares of Class C common stock) from certain of the Virtu Members in connection with the IPO, (iii) the purchase of Virtu Financial Units (along with the corresponding shares of Class C common stock) and the exchange of Virtu Financial Units (along with the corresponding shares of Class C common stock) for shares of Class A common stock in connection with the secondary offerings completed in September 2016 and November 2015 (the “Secondary Offerings”), the Company recorded a deferred tax asset of $220.8 million associated with the increase in tax basis that results from such events. Payments to certain Virtu Members in respect of the purchases were expected to range from approximately $0.3 million to $12.8 million per year over the next 15 years . The corresponding deduction to additional paid-in capital was approximately $19.9 million for the difference between the tax receivable agreements liability and the related deferred tax asset. As a result of the reduction in the U.S. corporate income tax rate as described below, the aforementioned deferred tax asset and related payment liability were subsequently reduced as described below. The amounts recorded as of March 31, 2018 are based on best estimates available at the respective dates and may be subject to change after the filing of the Company’s U.S. federal and state income tax returns for the years in which tax savings were realized. The 2017 Tax Act includes, among other items, a permanent reduction to the U.S. corporate income tax rate from 35% to 21% effective January 1, 2018 as further described in Note 14 "Income taxes" . As a result, at December 31, 2017 , the Company recorded a reduction of its tax receivable agreement obligation of $86.6 million . As further described in Note 14 “Income Taxes”, the Company also recorded a reduction of its deferred tax assets, including deferred tax assets relating to the deferred tax assets described above. At March 31, 2018 and December 31, 2017 , the Company’s remaining deferred tax assets were approximately $99.1 million and $101.6 million , respectively, and the Company’s liabilities over the next 15 years, pursuant to the tax receivable agreements are approximately $147.0 million and 147.0 million , respectively. For the tax receivable agreements discussed above, the cash savings realized by the Company are computed by comparing the actual income tax liability of the Company to the amount of such taxes the Company would have been required to pay had there been (i) no increase to the tax basis of the assets of Virtu Financial as a result of the purchase or exchange of Virtu Financial Units, (ii) no tax benefit from the tax basis in the intangible assets of Virtu Financial on the date of the IPO and (iii) no tax benefit as a result of the Net Operating Losses (“NOLs”) and other tax attributes of Virtu Financial. Subsequent adjustments of the tax receivable agreements obligations due to certain events (e.g., changes to the expected realization of NOLs or changes in tax rates) will be recognized within income before taxes and noncontrolling interests in the condensed consolidated statements of comprehensive income.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	3 Months Ended
	Mar. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Goodwill and Intangible Assets Prior to the Acquisition, the Company was managed and operated as one business, and accordingly, operated under one reportable segment. As a result of the acquisition of KCG, beginning in the third quarter of 2017 the Company has three operating segments: (i) Market Making; (ii) Execution Services; and (iii) Corporate. The Company allocated goodwill to the new reporting units using a relative fair value approach. In addition, the Company performed an assessment of potential goodwill impairment for all reporting units immediately prior to the reallocation and determined that no impairment was indicated. The following table presents the details of goodwill by segment: (in thousands) Market Making Execution Services Corporate Total Balance as of December 31, 2017 $ 755,292 $ 89,591 $ — $ 844,883 Goodwill adjustment allocated to BondPoint — (8,300 ) — (8,300 ) Balance as of March 31, 2018 $ 755,292 $ 81,291 $ — $ 836,583 As of March 31, 2018 and December 31, 2017 , the Company’s total amount of goodwill recorded was $836.6 million and $844.9 million , respectively. As described in Note 4 "Sale of BondPoint" , the Company allocated $8.3 million goodwill to BondPoint as part of the sale. No goodwill impairment was recognized in the three months ended March 31, 2018 and 2017 . Acquired intangible assets consisted of the following as of March 31, 2018 and December 31, 2017 : As of March 31, 2018 (in thousands) Gross Carrying Amount Accumulated Amortization Net Carrying Amount Useful Lives (Years) Purchased technology $ 110,000 $ 110,000 $ — 1.4 to 2.5 ETF issuer relationships 950 585 365 9 ETF buyer relationships 950 586 364 9 Leases 1,800 547 1,253 3 FCC licenses 200 26 174 7 Technology 60,000 15,047 44,953 1 to 6 Customer relationships 49,000 2,843 46,157 12 to 17 Favorable occupancy leases 5,895 612 5,283 7 Exchange memberships 5,838 — 5,838 Indefinite $ 234,633 $ 130,246 $ 104,387 As of December 31, 2017 (in thousands) Gross Carrying Amount Accumulated Amortization Net Carrying Amount Useful Lives Purchased technology $ 110,000 $ 110,000 $ — 1.4 to 2.5 ETF issuer relationships 950 559 391 9 ETF buyer relationships 950 560 390 9 Leases 1,800 397 1,403 3 FCC licenses 200 19 181 7 Technology 60,000 9,644 50,356 1 to 6 Customer relationships 49,000 1,822 47,178 12 to 17 Favorable occupancy leases 5,895 408 5,487 7 Exchange memberships 5,838 — 5,838 Indefinite $ 234,633 $ 123,409 $ 111,224 Amortization expense relating to finite-lived intangible assets was approximately $6.9 million , and $0.05 million for the three months ended March 31, 2018 , and 2017 , respectively. This is included in amortization of purchased intangibles and acquired capitalized software in the accompanying condensed consolidated statements of comprehensive income.

Receivables from_Payables to Br

Receivables from/Payables to Broker-Dealers and Clearing Organizations	3 Months Ended
	Mar. 31, 2018
Due to and from Broker-Dealers and Clearing Organizations [Abstract]
Receivables from/Payables to Broker-Dealers and Clearing Organizations	Receivables from/Payables to Broker-Dealers and Clearing Organizations The following is a summary of receivables from and payables to brokers-dealers and clearing organizations at March 31, 2018 and December 31, 2017 : (in thousands) 2018 2017 Assets Due from prime brokers $ 153,716 $ 219,573 Deposits with clearing organizations 257,832 112,847 Net equity with futures commission merchants 308,964 203,711 Unsettled trades with clearing organization 430,514 173,778 Securities failed to deliver 271,287 248,088 Commissions and fees 11,726 14,021 Total receivables from broker-dealers and clearing organizations $ 1,434,039 $ 972,018 Liabilities Due to prime brokers $ 390,364 $ 197,439 Net equity with futures commission merchants 40,665 44,526 Unsettled trades with clearing organization 150,205 420,029 Securities failed to receive 65,715 51,143 Commissions and fees 1,839 3,068 Total payables to broker-dealers and clearing organizations $ 648,788 $ 716,205 Included as a deduction from “Due from prime brokers” and “Net equity with futures commission merchants” is the outstanding principal balance on all of the Company’s short-term credit facilities (described in Note 9 “Collateralized Transactions”) of approximately $131.4 million and $205.7 million as of March 31, 2018 and December 31, 2017 , respectively. The loan proceeds from the credit facilities are available only to meet the initial margin requirements associated with the Company’s ordinary course futures and other trading positions, which are held in the Company’s trading accounts with an affiliate of the respective financial institutions. The credit facilities are fully collateralized by the Company’s trading accounts and deposit accounts with these financial institutions. “Securities failed to deliver” and “Securities failed to receive” include amounts with a clearing organization and other broker-dealers.

Collateralized Transactions

Collateralized Transactions	3 Months Ended
	Mar. 31, 2018
Collateralized Agreements [Abstract]
Collateralized Transactions	Collateralized Transactions The Company is permitted to sell or repledge securities received as collateral and use these securities to secure repurchase agreements, enter into securities lending transactions or deliver these securities to counterparties or clearing organizations to cover short positions. At March 31, 2018 and December 31, 2017 , substantially all of the securities received as collateral have been repledged. The fair value of the collateralized transactions at March 31, 2018 and December 31, 2017 are summarized as follows: (in thousands) 2018 2017 Securities received as collateral: Securities borrowed $ 1,201,721 $ 1,415,793 $ 1,201,721 $ 1,415,793 In the normal course of business, the Company pledges qualified securities with clearing organizations to satisfy daily margin and clearing fund requirements. Financial instruments owned and pledged, where the counterparty has the right to repledge, at March 31, 2018 and December 31, 2017 consisted of the following: (in thousands) 2018 2017 Equities $ 571,997 $ 586,251 U.S. and Non-U.S. government obligations 200 99 Exchange traded notes 38,339 8,693 $ 610,536 $ 595,043

Borrowings

Borrowings	3 Months Ended
	Mar. 31, 2018
Debt Disclosure [Abstract]
Borrowings	Borrowings Broker-Dealer Credit Facilities The Company is a party to two secured credit facilities with a financial institution to finance overnight securities positions purchased as part of its ordinary course broker-dealer market making activities. One of the facilities (the “Uncommitted Facility”), is provided on an uncommitted basis collateralized by one of the Company’s broker-dealer subsidiaries trading and deposit account with the financial institution. On November 3, 2017, the Company entered the second credit facility (“Revolving Credit Facility”) with the same financial institution for an aggregated borrowing limit of $500.0 million . The Revolving Credit Facility consists two borrowing bases: Borrowing Base A Loan is to be used to finance the purchase and settlement of securities; Borrowing Base B Loan is to be used to fund margin deposit with the NSCC. Each of the three broker-dealers has a sublimit under Borrowing Base A Loan, from $25 million to $500 million , which bears interest at the adjusted LIBOR or base rate plus 1.25% per annum. Two out of the three broker-dealers have sublimit under Borrowing Base B Loan, from $40 million to $100 million , which bears interest at the adjusted LIBOR or base rate plus 2.50% per annum. A commitment fee of 0.50% per annum on the average daily unused portion of this facility is payable quarterly in arrears. The following summarizes the Company’s broker-dealer credit facilities carrying value, net of unamortized debt issuance costs, where applicable: At March 31, 2018 (in thousands) Interest Rate Financing Available Borrowing Outstanding Deferred Debt Issuance Cost Outstanding Borrowings, net Broker-dealer credit facilities: Uncommitted facility 2.68% $ 350,000 $ 17,500 $ (1,580 ) $ 15,920 Revolving credit facility 3.13% 500,000 7,000 (1,976 ) 5,024 $ 850,000 $ 24,500 $ (3,556 ) $ 20,944 At December 31, 2017 (in thousands) Interest Rate Financing Available Borrowing Outstanding Deferred Debt Issuance Cost Outstanding Borrowings, net Broker-dealer credit facilities: Uncommitted facility 2.42% $ 150,000 $ 25,000 $ — $ 25,000 Revolving credit facility 2.81% 500,000 7,000 (4,117 ) 2,883 $ 650,000 $ 32,000 $ (4,117 ) $ 27,883 The following summarizes interest expense for the broker-dealer facilities. Interest expense is included within interest and dividends expense in the accompanying condensed consolidated statements of comprehensive income. Three Months Ended March 31, (in thousands) 2018 2017 Broker-dealer credit facilities: Uncommitted facility $ 446 $ 415 Committed facility (1) — 7 Revolving credit facility 98 — $ 544 $ 422 (1) Facility was terminated in July 2017. Short-Term Credit Facilities The Company maintains short-term credit facilities with various prime brokers and other financial institutions from which it receives execution or clearing services. The proceeds of these facilities are used to meet margin requirements associated with the products traded by the Company in the ordinary course, and amounts borrowed are collateralized by the Company’s trading accounts with the applicable financial institution. At March 31, 2018 Weighted Average Financing Borrowing Short-Term Credit Facilities: Short-term credit facilities (2) 4.04% $ 535,000 $ 131,382 $ 535,000 $ 131,382 At December 31, 2017 Weighted Average Interest Rate Financing Available Borrowing Outstanding Short-Term Credit Facilities: Short-term credit facilities (2) 3.86% $ 543,000 $ 205,677 $ 543,000 $ 205,677 (2) Outstanding borrowings were included with receivable from/ payable to broker-dealers and clearing organization within the condensed consolidated statements of financial condition. Interest expense in relation to the facilities for the three months ended March 31, 2018 and 2017 was approximately $1.5 million and $1.7 million , respectively. Long-Term Borrowings The following summarizes the Company’s long-term borrowings, net of unamortized discount and debt issuance costs, where applicable: At March 31, 2018 (in thousands) Maturity Interest Outstanding Principal Discount Deferred Debt Issuance Cost Outstanding Borrowings, net Long-term borrowings: Fourth Amended and Restated Credit Agreement December 2021 4.94% $ 624,000 $ (650 ) $ (13,101 ) $ 610,249 Senior secured Second Lien Notes June 2022 6.75% 500,000 — (21,673 ) 478,327 SBI bonds January 2020 5.00% 32,932 — (44 ) 32,888 $ 1,156,932 $ (650 ) $ (34,818 ) $ 1,121,464 At December 31, 2017 (in thousands) Maturity Date Interest Rate Outstanding Principal Discount Deferred Debt Issuance Cost Outstanding Borrowings, net Long-term borrowings: Fourth Amended and Restate Credit Agreement December 2021 5.13% $ 900,000 $ (999 ) $ (18,504 ) $ 880,497 Senior secured Second Lien Notes June 2022 6.75% 500,000 — (22,961 ) 477,039 SBI bonds January 2020 5.00% 31,059 — (47 ) 31,012 $ 1,431,059 $ (999 ) $ (41,512 ) $ 1,388,548 Fourth Amended and Restated Credit Agreement To finance the Acquisition, on June 30, 2017, Virtu Financial and VFH Parent LLC (“VFH”) entered into a fourth amended and restated credit agreement (the “Fourth Amended and Restated Credit Agreement”) with the lenders party thereto and JPMorgan Chase Bank, N.A., as administrative agent, sole lead arranger and bookrunner, which amended and restated in its entirety the existing Credit Agreement, and upon the closing of the Acquisition of KCG, provided for an aggregate $1.15 billion of first lien secured term loans (the “Term Loan Facility”). For the three months ended March 31, 2018 , $276.0 million of prepayments were made under the Fourth Amended and Restated Credit Agreement, for an aggregate total of $526.0 million of principal prepayments under the Term Loan Facility since its closing. VFH also entered into a repricing transaction during January 2018 to reprice the senior secured term loans under the Fourth Amended and Restated Credit Agreement at LIBOR plus 3.25% . In connection with the debt refinancing and the debt prepayment, the Company accelerated approximately $6.0 million unamortized financing costs incurred that were scheduled to be amortized over the term of the loan, including original issue discount and underwriting and legal fees, which is included within debt issue cost related to debt refinancing in the consolidated statements of comprehensive income. The Fourth Amended and Restated Credit Agreement contains certain customary covenants and certain customary events of default, including relating to a change of control. If an event of default occurs and is continuing, the lenders under the Fourth Amended and Restated Credit Agreement will be entitled to take various actions, including the acceleration of amounts outstanding under the Fourth Amended and Restated Credit Agreement and all actions permitted to be taken by a secured creditor in respect of the collateral securing the obligations under the Fourth Amended and Restated Credit Agreement. Senior Secured Second Lien Notes To finance the Acquisition, on June 16, 2017, the Escrow Issuer and Orchestra Co-Issuer, Inc. (the “Co-Issuer”) completed the offering of $500.0 million aggregate principal amount of 6.750% Senior Secured Second Lien Notes due 2022 (the “Notes”). The Notes were issued under an Indenture, dated June 16, 2017 (the “Indenture”), among the Escrow Issuer, the Co-Issuer and U.S. Bank National Associations, as trustee and collateral agent. On July 20, 2017, VFH assumed all of the obligations of the Escrow Issuer under the Indenture and the Notes. The Notes are guaranteed by Virtu Financial and each of Virtu Financial’s wholly-owned domestic restricted subsidiaries that guarantees the Fourth Amended and Restated Credit Agreement. The Indenture imposes certain limitations on the Company, and contains certain customary events of default, including, among others, payment defaults related to the failure to pay principal or interest on Notes, covenant defaults, final maturity default or cross-acceleration with respect to material indebtedness and certain bankruptcy events. The gross proceeds from the Notes were deposited into a segregated escrow account with an escrow agent. The proceeds were released from escrow as of the Closing Date and were used to finance, in part, the Acquisition, and to repay certain indebtedness of the Company and KCG. (See Note 3 “Acquisition of KCG Holdings, Inc.” for further details). SBI Bonds On July 25, 2016, VFH issued Japanese Yen Bonds (collectively the “SBI Bonds”) in the aggregate principal amount of ¥3.5 billion ( $33.1 million at issuance date) to SBI Life Insurance Co., Ltd. and SBI Insurance Co., Ltd. The proceeds from the SBI Bonds were used to partially fund the investment in SBI (as described in Note 11 “Financial assets and liabilities”). The SBI Bonds are guaranteed by Virtu Financial. The SBI Bonds are subject to fluctuations on the Japanese Yen currency rates relative to the Company’s reporting currency (U.S. Dollar) with the changes reflected in other, net in the condensed consolidated statements of comprehensive income. The principal balance was ¥3.5 billion ( $32.9 million ) as of March 31, 2018 and ¥3.5 billion ( $31.0 million ) as of December 31, 2017 . The Company recorded a loss of $1.9 million and $1.5 million due to the change in currency rates during the three months ended March 31, 2018 and 2017 , respectively. Aggregate future required minimum principal payments based on the terms of the long-term borrowings at March 31, 2018 were as follows: (in thousands) 2018 $ — 2019 — 2020 32,932 2021 and thereafter 1,124,000 Total principal of long-term borrowings $ 1,156,932

Financial Assets and Liabilitie

Financial Assets and Liabilities	3 Months Ended
	Mar. 31, 2018
Fair Value Disclosures [Abstract]
Financial Assets and Liabilities	Financial Assets and Liabilities Financial Instruments Measured at Fair Value The fair value of equities, options, on the run U.S. government obligations and exchange traded notes is estimated using recently executed transactions and market price quotations in active markets and are categorized as Level 1 with the exception of inactively traded equities and certain financial instruments noted in the preceding paragraph, which are categorized as Level 2. The Company’s corporate bonds, derivative contracts and other U.S. and non-U.S. government obligations have been categorized as Level 2. Fair value of the Company’s derivative contracts is based on the indicative prices obtained from broadly distributed bank and broker dealers, as well as management’s own analyses. The indicative prices have been independently validated through the Company’s risk management systems, which are designed to check prices with information independently obtained from exchanges and venues where such financial instruments are listed or to compare prices of similar instruments with similar maturities for listed financial futures in foreign exchange. As of March 31, 2017 , the Company began pricing certain financial instruments held for trading at fair value based on theoretical prices which can differ from quoted market prices. The theoretical prices reflect price adjustments primarily caused by the fact that the Company continuously prices its financial instruments based on all available information. This information includes prices for identical and near-identical positions, as well as the prices for securities underlying the Company’s positions, on other exchanges that are open after the exchange on which the financial instruments is traded closes. The Company validates that all price adjustments can be substantiated with market inputs and checks the theoretical prices independently. Consequently, such financial instruments are classified as Level 2. The Company concluded that this is a change in accounting estimate and no retrospective adjustments were necessary. Fair value measurements for those items measured on a recurring basis are summarized below as of March 31, 2018 : March 31, 2018 (in thousands) Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Counterparty and Cash Collateral Netting Total Fair Value Assets Financial instruments owned, at fair value: Equity securities $ 956,518 $ 1,139,469 $ — $ — $ 2,095,987 U.S. and Non-U.S. government obligations 800 18,207 — — 19,007 Corporate Bonds — 75,534 — — 75,534 Exchange traded notes 64,730 30,368 — — 95,098 Currency forwards — 702,889 — (700,655 ) 2,234 Options 9,210 — — — 9,210 1,031,258 1,966,467 — (700,655 ) 2,297,070 Financial instruments owned, pledged as collateral: Equity securities $ 309,313 $ 262,684 $ — $ — $ 571,997 U.S. and Non-U.S. government obligations 200 — — — 200 Exchange traded notes 22,418 15,921 — — 38,339 331,931 278,605 — — 610,536 Other Assets Equity investment $ — $ — $ 42,478 $ — $ 42,478 Exchange stock 2,154 — — — 2,154 Other (1) — 56,179 — — 56,179 2,154 56,179 42,478 — 100,811 Liabilities Financial instruments sold, not yet purchased, at fair value: Equity securities $ 1,584,268 $ 1,132,360 $ — $ — $ 2,716,628 U.S. and Non-U.S. government obligations 1,998 25,207 — — 27,205 Corporate Bonds 40,007 — — — 40,007 Exchange traded notes 3,714 38,393 — — 42,107 Currency forwards — 725,422 — (720,464 ) 4,958 Options 15,548 — — — 15,548 $ 1,645,535 $ 1,921,382 $ — $ (720,464 ) $ 2,846,453 (1) Other primarily consists of a $56.2 million receivable from Bats related to the sale of KCG Hotspot. Fair value measurements for those items measured on a recurring basis are summarized below as of December 31, 2017 : December 31, 2017 (in thousands) Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Counterparty and Cash Collateral Netting Total Fair Value Assets Financial instruments owned, at fair value: Equity securities $ 758,596 $ 1,167,995 $ — $ — $ 1,926,591 Non-U.S. government obligations 5,968 16,815 — — 22,783 Corporate Bonds — 60,975 — — 60,975 Exchange traded notes 13,576 68,819 — — 82,395 Currency forwards — 2,045,487 — (2,027,697 ) 17,790 Options 7,045 — — — 7,045 $ 785,185 $ 3,360,091 $ — $ (2,027,697 ) $ 2,117,579 Financial instruments owned, pledged as collateral: Equity securities $ 410,670 $ 175,581 $ — $ — $ 586,251 U.S. and Non-U.S. government obligations 99 — — — 99 Exchange traded notes 82 8,611 — — 8,693 $ 410,851 $ 184,192 $ — $ — $ 595,043 Other Assets Equity investment $ — $ — $ 40,588 $ — $ 40,588 Exchange stock 1,952 — — — 1,952 Other (2) — 55,824 — — 55,824 $ 1,952 $ 55,824 $ 40,588 $ — $ 98,364 Liabilities Financial instruments sold, not yet purchased, at fair value: Equity securities $ 847,816 $ 1,355,616 $ — $ — $ 2,203,432 Exchange traded notes 1,514 54,248 — — 55,762 Currency forwards — 2,032,017 — (2,024,991 ) 7,026 Options 5,839 — — — 5,839 $ 874,109 $ 3,535,480 $ — $ (2,024,991 ) $ 2,384,598 (2) Other primarily consists of a $55.8 million receivable from Bats related to the sale of KCG Hotspot. SBI Investment As of March 31, 2018 , the fair value of SBI Investment was determined using the discounted cash flow method, an income approach, with the discount rate of 15.0% applied to the cash flow forecasts. The Company also used a market approach based on 14 x average price/earnings multiples of comparable companies to corroborate the income approach. The fair value of the SBI Investment at March 31, 2018 was determined by taking the weighted average of enterprise valuations based on discounted cash flow on projected income from the next five years , the implied enterprise valuations on comparable companies, and the implied enterprise valuations on comparable transactions. The fair value measurement is highly sensitive to significant changes in the unobservable inputs and significant increases (decreases) in discount rate or decreases (increases) in price/earnings multiples would result in a significantly lower (higher) fair value measurement. Changes in the fair value of the SBI Investment are reflected in other, net in the condensed consolidated statements of comprehensive income. There were no transfers of financial instruments between levels during the three months ended March 31, 2018 and 2017 . Receivable from Bats Global Markets, Inc. (“Bats”) In March 2015, KCG sold KCG Hotspot, an institutional spot foreign exchange electronic communications networks (“ECN”), to Bats, which is now a subsidiary of CBOE Holdings, Inc. KCG and Bats agreed to share certain tax benefits, which as of March 31, 2018 comprise a $50.0 million payment and an annual payment of up to $6.6 million , both of which were paid in April 2018. The Company has elected the fair value option related to the receivable from Bats and considers the receivable to be a Level 2 asset in the fair value hierarchy as the fair value is derived from observable significant inputs such as contractual cash flows and market discount rates. The remaining additional potential payments of $56.6 million are recorded at a fair value of $56.2 million in other assets on the condensed consolidated statements of financial condition as of March 31, 2018 . Financial Instruments Not Measured at Fair Value The table below presents the carrying value, fair value and fair value hierarchy category of certain financial instruments that are not measured at fair value on the condensed consolidated statement of financial condition. The table below excludes non-financial assets and liabilities. The carrying value of financial instruments not measured at fair value categorized in the fair value hierarchy as Level 1 and Level 2 approximates fair value due to the relatively short-term nature of the underlying assets. The fair value of the Company’s long-term borrowings is categorized as Level 2 in the fair value hierarchy, which is based on quoted prices from the market. The table below summarizes financial assets and liabilities not measured at fair value on a recurring basis as of March 31, 2018 : March 31, 2018 Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Carrying Value Fair Value (Level 1) (Level 2) (Level 3) Assets Cash and cash equivalents $ 637,308 $ 637,308 $ 637,308 $ — $ — Securities borrowed 1,232,048 1,232,048 — 1,232,048 — Securities purchased under agreements to resell 602 602 — 602 — Receivables from broker dealers and clearing organizations 1,434,039 1,434,039 70,143 1,363,896 — Total Assets $ 3,303,997 $ 3,303,997 $ 707,451 $ 2,596,546 $ — Liabilities Short-term borrowings $ 20,944 $ 20,944 $ — $ 20,944 $ — Long-term borrowings 1,121,464 1,193,167 — 1,193,167 — Securities loaned 936,061 936,061 — 936,061 — Securities sold under agreements to repurchase 265,401 265,401 — 265,401 — Payables to broker dealer and clearing organizations 648,788 648,788 861 647,927 — Total Liabilities $ 2,992,658 $ 3,064,361 $ 861 $ 3,063,500 $ — The table below summarizes financial assets and liabilities not measured at fair value on a recurring basis as of December 31, 2017 : December 31, 2017 Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Carrying Value Fair Value (Level 1) (Level 2) (Level 3) Assets Cash and cash equivalents $ 532,887 $ 532,887 $ 532,887 $ — $ — Securities borrowed 1,471,172 1,471,172 — 1,471,172 — Receivables from broker dealers and clearing organizations 972,018 972,018 36,513 935,505 — Total Assets $ 2,976,077 $ 2,976,077 $ 569,400 $ 2,406,677 $ — Liabilities Short-term borrowings $ 27,883 $ 27,883 $ — $ 27,883 $ — Long-term borrowings 1,388,548 1,465,489 — 1,465,489 — Securities loaned 754,687 754,687 — 754,687 — Securities sold under agreements to repurchase 390,642 390,642 — 390,642 — Payables to broker dealer and clearing organizations 716,205 716,205 2,925 713,280 — Total Liabilities $ 3,277,965 $ 3,354,906 $ 2,925 $ 3,351,981 $ — The following presents the changes in Level 3 financial instruments measured at fair value on a recurring basis: March 31, 2018 (in thousands) December 31, 2017 Purchases Total Realized and Unrealized Gains / (Losses) Net Transfers into (out of) Level 3 Settlement March 31, 2018 Change in Net Unrealized Gains / (Losses) on Investments still held at March 31, 2018 Assets Other assets: Equity investment $ 40,588 $ — $ 1,890 $ — $ — $ 42,478 $ 1,890 Total $ 40,588 $ — $ 1,890 $ — $ — $ 42,478 $ 1,890 December 31, 2017 (in thousands) December 31, 2016 Purchases Total Realized and Unrealized Gains / (Losses) Net Transfers into (out of) Level 3 Settlement December 31, 2017 Change in Net Unrealized Gains / (Losses) on Investments still held at December 31, 2017 Assets Other assets: Equity investment $ 36,031 $ — $ 4,557 $ — $ — $ 40,588 $ 4,557 Other — 3,000 — — (3,000 ) — — Total $ 36,031 $ 3,000 $ 4,557 $ — $ (3,000 ) $ 40,588 $ 4,557 Offsetting of Financial Assets and Liabilities The Company does not net securities borrowed and securities loaned, or securities purchased under agreements to resell and securities sold under agreements to repurchase. These financial instruments are presented on a gross basis in the condensed consolidated statements of financial condition. In the tables below, the amounts of financial instruments owned that are not offset in the condensed consolidated statements of financial condition, but could be netted against financial liabilities with specific counterparties under legally enforceable master netting agreements in the event of default, are presented to provide financial statement readers with the Company’s estimate of its net exposure to counterparties for these financial instruments. The following tables set forth the gross and net presentation of certain financial assets and financial liabilities as of March 31, 2018 and December 31, 2017 . March 31, 2018 Gross Amounts of Recognized Assets Gross Amounts Offset in the Condensed Consolidated Statement of Financial Condition Net Amounts of Assets Presented in the Condensed Consolidated Statement of Financial Condition Gross Amounts Not Offset In the Statement of Financial Condition (in thousands) Financial Instruments Cash Collateral Received Net Amount Offsetting of Financial Assets: Securities borrowed $ 1,232,048 $ — $ 1,232,048 $ (1,202,760 ) $ (2,624 ) $ 26,664 Securities purchased under agreements to resell 602 — 602 (602 ) — — Trading assets, at fair value: Currency forwards 702,889 (700,655 ) 2,234 — — 2,234 Options 9,210 — 9,210 (1 ) — 9,209 Total $ 1,944,749 $ (700,655 ) $ 1,244,094 $ (1,203,363 ) $ (2,624 ) $ 38,107 Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Consolidated Statement of Financial Condition Net Amounts of Assets Presented in the Consolidated Statement of Financial Condition Gross Amounts Not Offset In the Statement of Financial Condition (in thousands) Financial Instruments Cash Collateral Pledged Net Amount Offsetting of Financial Liabilities: Securities loaned $ 936,061 $ — $ 936,061 $ (929,457 ) $ (884 ) $ 5,720 Securities sold under agreements to repurchase 265,401 — 265,401 (265,401 ) — — Trading liabilities, at fair value: Currency forwards 725,422 (720,464 ) 4,958 — 4,958 Options 15,548 — 15,548 (1 ) — 15,547 Total $ 1,942,432 $ (720,464 ) $ 1,221,968 $ (1,194,859 ) $ (884 ) $ 26,225 December 31, 2017 Gross Amounts of Recognized Assets Gross Amounts Offset in the Consolidated Statement of Financial Condition Net Amounts of Assets Presented in the Consolidated Statement of Financial Condition Gross Amounts Not Offset In the Statement of Financial Condition (in thousands) Financial Instruments Cash Collateral Received Net Amount Offsetting of Financial Assets: Securities borrowed $ 1,471,172 $ — $ 1,471,172 $ (1,418,672 ) $ (13,318 ) $ 39,182 Trading assets, at fair value: Currency forwards 2,045,487 (2,027,697 ) 17,790 — — 17,790 Options 7,045 — 7,045 (45 ) — 7,000 Total $ 3,523,704 $ (2,027,697 ) $ 1,496,007 $ (1,418,717 ) $ (13,318 ) $ 63,972 Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Consolidated Statement of Financial Condition Net Amounts of Assets Presented in the Consolidated Statement of Financial Condition Gross Amounts Not Offset In the Statement of Financial Condition (in thousands) Financial Instruments Cash Collateral Pledged Net Amount Offsetting of Financial Liabilities: Securities loaned $ 754,687 $ — $ 754,687 $ (737,731 ) $ (10,776 ) $ 6,180 Securities sold under agreements to repurchase 390,642 — 390,642 (390,642 ) — — Trading liabilities, at fair value: Currency forwards 2,032,017 (2,024,991 ) 7,026 — 7,026 Options 5,839 — 5,839 (56 ) — 5,783 Total $ 3,183,185 $ (2,024,991 ) $ 1,158,194 $ (1,128,429 ) $ (10,776 ) $ 18,989 The following table presents gross obligations for securities sold under agreements to repurchase and for securities lending transactions by remaining contractual maturity and the class of collateral pledged. March 31, 2018 Remaining Contractual Maturity (in thousands) Overnight and Continuous Less than 30 days 30 - 60 days 61 - 90 Days Total Repurchase agreements: Equity securities $ 401 $ — $ 65,000 $ 200,000 $ 265,401 U.S. and Non-U.S. government obligations — — — — Total $ 401 $ — $ 65,000 $ 200,000 $ 265,401 Securities lending transactions: Equity securities $ 936,061 $ — $ — $ — $ 936,061 Total $ 936,061 $ — $ — $ — $ 936,061 December 31, 2017 Remaining Contractual Maturity (in thousands) Overnight and Continuous Less than 30 days 30 - 60 days 61 - 90 Days Total Repurchase agreements: Equity securities $ — $ 100,000 $ 90,000 $ 200,000 $ 390,000 U.S. and Non-U.S. government obligations 642 — — — 642 Total $ 642 $ 100,000 $ 90,000 $ 200,000 $ 390,642 Securities lending transactions: Equity securities $ 754,687 $ — $ — $ — $ 754,687 Total $ 754,687 $ — $ — $ — $ 754,687

Derivative Instruments

Derivative Instruments	3 Months Ended
	Mar. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	Derivative Instruments The fair value of the Company’s derivative instruments on a gross basis consisted of the following at March 31, 2018 and December 31, 2017 : (in thousands) March 31, 2018 December 31, 2017 Derivatives Assets Financial Statements Location Fair Value Notional Fair Value Notional Derivative instruments not designated as hedging instruments: Equities futures Receivables from broker dealers and clearing organizations $ 183 $ 4,836,630 $ (505 ) $ 1,985,770 Commodity futures Receivables from broker dealers and clearing organizations 39,965 20,971,297 971 21,231,001 Currency futures Receivables from broker dealers and clearing organizations 32,042 2,075,544 26,548 3,994,412 Fixed income futures Receivables from broker dealers and clearing organizations 23 10,096 73 44,395 Options Financial instruments owned 9,210 793,423 7,045 682,369 Currency forwards Financial instruments owned 702,889 100,689,302 2,045,487 124,000,221 Derivatives Liabilities Financial Statements Location Fair Value Notional Fair Value Notional Derivative instruments not designated as hedging instruments: Equities futures Payables to broker dealers and clearing organizations $ 208 $ 139,033 $ (575 ) $ 142,658 Commodity futures Payables to broker dealers and clearing organizations 645 118,427 (1,602 ) 130,042 Currency futures Payables to broker dealers and clearing organizations (3,279 ) 2,531,734 (13,947 ) 7,756,958 Fixed income futures Payables to broker dealers and clearing organizations (169 ) 13,016 (1 ) 2,584 Options Financial instruments sold, not yet purchased 15,548 769,273 5,839 681,147 Currency forwards Financial instruments sold, not yet purchased 725,058 100,700,387 2,032,017 123,993,234 Derivative instruments designated as hedging instruments: Currency forwards Financial instruments sold, not yet purchased (364 ) 15,964 (514 ) 16,115 Amounts included in receivables from and payables to broker-dealers and clearing organizations represent net variation margin on long and short futures contracts. The following table summarizes the net gain from derivative instruments not designated as hedging instruments under ASC 815, which are recorded in trading income, net, and from those designated as hedging instrument under ASC 815, which are recorded in accumulated other comprehensive income in the accompanying condensed consolidated statements of comprehensive income for the three months ended March 31, 2018 and 2017 . March 31, (in thousands) Financial Statements Location 2018 2017 Derivative instruments not designated as hedging instruments: Futures Trading income, net $ (436,414 ) $ 165,590 Currency forwards Trading income, net 85,910 (51,381 ) Options Trading income, net 1,102 1 $ (349,402 ) $ 114,210 Derivative instruments designated as hedging instruments: Foreign exchange - forward contract Accumulated other comprehensive income $ 150 $ —

Revenues from Contracts with Cu

Revenues from Contracts with Customers	3 Months Ended
	Mar. 31, 2018
Revenue Recognition [Abstract]
Revenues from Contracts with Customers	Revenues from Contracts with Customers Revenue Recognitions The Company adopted ASC Topic 606, Revenue from Contracts with Customers as of January 1, 2018 in the condensed consolidated financial statements by applying the modified retrospective method. The Company’s revenue recognition methods for its contracts with customers prior to the adoption of Topic 606 are consistent with its methods after the adoption of Topic 606. Accordingly, the adoption of the new standard did not result in a transition adjustment to opening retained earnings, and as a result, revenues for contracts with customers would not have been adjusted in prior periods and are not presented herein on an adjusted basis. The new revenue guidance does not apply to revenue associated with financial instruments, including loans and securities that are accounted for under other U.S. GAAP, and as a result, did not have an impact on the elements of the Company’s condensed consolidated statement of comprehensive income most closely associated with financial instruments, including trading income, net and interest and dividend income. The new standard primarily impacts the presentation of the following revenue streams: • Commissions, net. The Company earns commission revenue by acting as an agent on behalf of customers. The Company’s performance obligations consist of trade execution and clearing services and are satisfied on the trade date; accordingly, commissions revenues are recorded on the trade date. Commission revenues are paid on settlement date; therefore, a receivable is recognized as of the trade date. Under a commission management program, the Company allows institutional clients to allocate a portion of their gross commissions to pay for research and other services provided by third parties. As the Company acts as an agent in these transactions, it records such expenses on a net basis within Commissions and technology services in the condensed consolidated statements of comprehensive income. • Technology services. The Company’s technology services revenues consist of technology licensing fees and agency commission fees. Technology licensing fees are earned from third parties for licensing of the Company’s proprietary risk management and trading infrastructure technology and the provision of associated management and hosting services. These fees include both upfront and annual recurring fees as well as, in certain cases, contingent fees based on customer revenues, which represent variable consideration. The services offered under these contracts are delivered as an integrated package and are interdependent and have the same pattern of transfer to the customer; accordingly, the Company measures and recognizes them as a single performance obligation. The performance obligation is satisfied over time, and, therefore, revenue is recognized as time passes. Variable consideration has not been included in the transaction price as the amount of consideration is contingent on factors outside the Company’s control and thus it is not probable that a significant reversal of cumulative revenue recognized will not occur. Recurring fees, which exclude variable consideration, are billed and collected on a quarterly basis and are included within Receivables from broker dealers and clearing organizations. Disaggregation of Revenues The following tables present the Company’s revenue from contracts with customers disaggregated by the services described above, by timing of revenue recognition, reconciled to the Company’s reportable segments, as well as disaggregation of the Company’s revenues by services and geographic region, for the three months ended March 31, 2018 : (in thousands) Market Making Execution Services Corporate Revenues from contract with Customers: Commissions, net 8,501 43,008 — Technology services — 2,335 — Total revenue from contract with customers 8,501 45,343 — Other sources of revenue 424,035 338,436 (1,262 ) Total Revenues 432,536 383,779 (1,262 ) Timing of revenue recognition: Services transferred at a point in time 432,536 381,444 (1,262 ) Services transferred over time — 2,335 — Total Revenues 432,536 383,779 (1,262 ) Information on Remaining Performance Obligations and Revenue Recognized As of March 31, 2018 , the aggregate amount of the transaction price allocated to the performance obligations relating to Technology Services revenues that are unsatisfied (or partially unsatisfied) was not material. Contract Assets and Contract Liabilities The timing of the revenue recognition may differ from the timing of payment from customers. The Company records a receivable when revenue is recognized prior to payment, and when the Company has an unconditional right to payment. The Company records contract liability when payment is received, prior to the time at which the satisfaction of the service obligation. We had receivables related to revenues from contracts with customers of $5.6 million and $7.1 million as of March 31, 2018 and December 31, 2017 .

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company is subject to U.S. federal, state and local income tax at the rate applicable to corporations less the rate attributable to the noncontrolling interest in Virtu Financial. These noncontrolling interests are subject to U.S. taxation as partnerships. Accordingly, for the three months ended March 31, 2018 and 2017 , the income attributable to these noncontrolling interests is reported in the condensed consolidated statements of comprehensive income, but the related U.S. income tax expense attributable to these noncontrolling interests is not reported by the Company as it is the obligation of the individual partners. The Company’s provisions for income taxes and effective tax rates were $58.5 million and 12.5% and $2.8 million and 11.8% for the three months ended March 31, 2018 and 2017 , respectively. Income tax expense is also affected by the differing effective tax rates in foreign, state and local jurisdictions where certain of the Company’s subsidiaries are subject to corporate taxation. Included in Other assets on the condensed consolidated statements of financial condition at March 31, 2018 and December 31, 2017 are current income tax receivables of $103.6 million and $115.2 million , respectively. The balances primarily comprises the income tax benefit of KCG net operating losses that were generated prior to the Acquisition and that are eligible to be carried back by the Company. Included in Accounts payable and accrued expenses and other liabilities on the condensed consolidated statements of financial condition at March 31, 2018 and December 31, 2017 are current tax liabilities of $52.6 million and $7.6 million , respectively. The balances primarily comprise income taxes owed to federal, state and local, and foreign tax jurisdictions based on income before taxes. Deferred income taxes arise primarily due to the amortization of the deferred tax assets recognized in connection with the IPO ( Note 6 "Tax Receivable Agreements" ) and the Acquisition of KCG ( Note 3 "Acquisition of KCG Holdings, Inc." ), differences in the valuation of financial assets and liabilities, and in connection with other temporary differences arising from the deductibility of compensation and depreciation expenses in different time periods for book and income tax return purposes. There are no expiration dates on the deferred tax assets. The Company’s deferred tax asset at March 31, 2018 and December 31, 2017 includes an alternative minimum tax credit carryforward of $0.6 million and $0.6 million , respectively, which can be either be refunded over a period of years or applied against future income tax liability pursuant to the 2017 Tax Act. The provisions of ASC 740 require that carrying amounts of deferred tax assets be reduced by a valuation allowance if, based on the available evidence, it is more likely than not that some portion or all of the deferred tax assets will not be realized. Accordingly, the need to establish valuation allowances for deferred tax assets is assessed periodically with appropriate consideration given to all positive and negative evidence related to the realization of the deferred tax assets. As a result of the Acquisition of KCG, the Company has non-U.S. net operating losses at March 31, 2018 and December 31, 2017 of $231.8 million and $231.8 million , respectively, and has recorded a related deferred tax asset of $43.5 million and $43.5 million , respectively. A full valuation allowance was also recorded against this deferred tax asset at March 31, 2018 and December 31, 2017 as it is more likely than not that this deferred tax asset will not be realized. No valuation allowance against the remaining deferred taxes was recorded as of March 31, 2018 and December 31, 2017 because it is more likely than not that these deferred tax assets will be fully realized. The Company is subject to taxation in U.S. federal, state, local and foreign jurisdictions. As of March 31, 2018 , the Company’s tax years for 2013 through 2017 and 2010 through 2017 are subject to examination by U.S. and non-U.S. tax authorities, respectively. As a result of the Acquisition of KCG, the Company has assumed any KCG tax exposures. KCG is currently subject to U.S. federal income tax examinations for 2013 through 2017, and to non-U.S. income tax examinations for the tax years 2007 through 2017. In addition, the Company is subject to state and local income tax examinations in various jurisdictions for the tax years 2007 through 2017. The final outcome of these examinations is not yet determinable. However, the Company anticipates that adjustments to the unrecognized tax benefits, if any, will not result in a material change to the financial condition, results of operations and cash flows. The 2017 Tax Act was signed into law on December 22, 2017 and significantly revises the U.S. corporate income tax by, among other things, lowering the statutory corporate tax rate from 35% to 21%, and eliminating certain deductions. The Company has not completed its determination of the accounting implications of the 2017 Tax Act on its tax accruals. However, the Company has reasonably estimated the effects of the 2017 Tax Act and recorded provisional amounts in our financial statements as of December 31, 2017 . The Company recorded a provisional deferred tax expense for the impact of the 2017 Tax Act of approximately $90.6 million , which is primarily composed of the remeasurement of federal net deferred tax assets as a result of the permanent reduction in the U.S. statutory corporate tax rate to 21% from 35%. During the first quarter of 2018, the Company did not make any adjustments due to the 2017 Tax Act. The Company expects to complete its analysis of the 2017 Tax Act by the third quarter of 2018, which is within the one-year measurement period prescribed by SEC Staff Accounting Bulletin No. 118. As the Company completes its analysis, collects and prepares necessary data, and interprets any additional guidance issued by the U.S. Treasury Department, the IRS, and other standard-setting bodies, it may make adjustments to the provisional amounts. Those adjustments may materially impact the Company’s provision for income taxes in the period in which the adjustments are made.

Commitments, Contingencies and

Commitments, Contingencies and Guarantees	3 Months Ended
	Mar. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments, Contingencies and Guarantees	Commitments, Contingencies and Guarantees Legal Proceedings In the ordinary course of business, the nature of the Company’s business subjects it to claims, lawsuits, regulatory examinations or investigations and other proceedings. The Company and its subsidiaries are subject to several of these matters at the present time. Given the inherent difficulty of predicting the outcome of litigation and regulatory matters, particularly in regulatory examinations or investigations or other proceedings in which substantial or indeterminate damages or fines are sought, or where such matters are in the early stages, the Company cannot estimate losses or ranges of losses for such matters where there is only a reasonable possibility that a loss may be incurred. In addition, there are numerous factors that result in a greater degree of complexity in class-action lawsuits as compared to other types of litigation. There can be no assurance that these matters will not have a material adverse effect on the Company’s results of operations in any future period, and a material judgment, fine or sanction could have a material adverse impact on the Company’s financial condition, results of operations and cash flows. However, it is the opinion of management, after consultation with legal counsel that, based on information currently available, the ultimate outcome of these matters will not have a material adverse impact on the business, financial condition or operating results of the Company although they might be material to the operating results for any particular reporting period. The Company carries directors’ and officers’ liability insurance coverage for potential claims, including securities actions, against the Company and its respective directors and officers. In connection with the Acquisition of KCG, a previously filed complaint, which was initially captioned Greenway v. KCG Holdings, Inc., et al., Case No. 2017-421-JTL and filed on behalf of a putative class in Delaware Chancery Court, was recaptioned Chester County Employees’ Retirement Fund v. KCG Holdings, Inc., et al. , amended and refiled on February 14, 2018 to include claims for the alleged breach of fiduciary duties against former KCG board members, claims against each of Virtu and Jefferies for allegedly aiding and abetting the KCG board members’ alleged breaches of fiduciary duty and a claim against Virtu and Jefferies for alleged civil conspiracy. No amount of damages is stated in the amended complaint, which Virtu intends to defend vigorously. Other Legal and Regulatory Matters The Company owns subsidiaries including regulated entities that are subject to extensive oversight under federal, state and applicable international laws as well as self-regulatory organization ("SRO") rules. Changes in market structure and the need to remain competitive require constant changes to the Company's systems, order routing and order handling procedures. The Company makes these changes while continuously endeavoring to comply with many complex laws and rules. Compliance, surveillance and trading issues common in the securities industry are monitored by, reported to, and/or reviewed in the ordinary course of business by the Company's regulators in the U.S. and abroad. As a major order flow execution destination, the Company is named from time to time in, or is asked to respond to a number of regulatory matters brought by U.S. regulators, foreign regulators, SROs, as well as actions brought by private plaintiffs, which arise from its business activities. There has recently been an increased focus by regulators on Anti-Money Laundering and sanctions compliance by broker-dealers and similar entities, as well as an enhanced interest on suspicious activity reporting and transactions involving microcap securities. In addition, there has been an increased focus by Congress, federal and state regulators, SROs and the media on market structure issues, and in particular, high frequency trading, best execution, internalization, ATS manner of operations, market fragmentation and complexity, colocation, cybersecurity, access to market data feeds and remuneration arrangements, such as payment for order flow and exchange fee structures. The Company has received information requests from various authorities, including the SEC, requesting, among other items, information regarding these market structure matters, to which the Company has responded or is in the process of responding. The Company is currently the subject of various regulatory reviews and investigations by federal, state and foreign regulators and SROs, including the SEC and the Financial Industry Regulatory Authority. In some instances, these matters may rise to a disciplinary action and/or a civil or administrative action. For example, the Autorité des Marchés Financiers ("AMF") fined the Company’s European subsidiary in the amount of €5.0 million (approximately $5.4 million ) based on its allegations that the subsidiary of a predecessor entity engaged in price manipulation and violations of the AMF General Regulation and Euronext Market Rules. The fine was subsequently reduced in 2017 to €3.3 million (approximately $3.9 million ). The Company had fully reserved for the monetary penalty as of March 31, 2018 and anticipates paying the fine during the year ended December 31, 2018. Indemnification Arrangements Consistent with standard business practices in the normal course of business, the Company has provided general indemnifications to its managers, officers, directors, employees, and agents against expenses, judgments, fines, settlements, and other amounts actually and reasonably incurred by such persons under certain circumstances as more fully disclosed in its operating agreement. The overall maximum amount of the obligations (if any) cannot reasonably be estimated as it will depend on the facts and circumstances that give rise to any future claims.

Capital Structure

Capital Structure	3 Months Ended
	Mar. 31, 2018
Equity [Abstract]
Capital Structure	Capital Structure The Company has four classes of authorized common stock. The Class A common stock and the Class C common stock have one vote per share. The Class B common stock and the Class D common stock have 10 votes per share. Shares of the Company’s common stock generally vote together as a single class on all matters submitted to a vote of the Company’s stockholders. For details related to the Company's IPO and Reorganization Transactions and other public offerings, refer to Note 16 "Capital structure" in the Company's 2017 Form 10-K. Amended and Restated 2015 Management Incentive Plan The Company’s board of directors and stockholders adopted the 2015 Management Incentive Plan, which became effective upon consummation of the IPO, and was subsequently amended and restated following receipt of approval from the Company’s stockholders on June 30, 2017. The Amended and Restated 2015 Management Incentive Plan provides for the grant of stock options, restricted stock units, and other awards based on an aggregate of 16,000,000 shares of Class A common stock, subject to additional sublimits, including limits on the total option grant to any one participant in a single year and the total performance award to any one participant in a single year. Acquisition of KCG On the Closing Date and in connection with the financing of the Acquisition, the Company issued 6,346,155 shares of the Company’s Class A common stock to Aranda for an aggregate purchase price of approximately $99.0 million and 39,725,979 shares of the Company Class A Common Stock to NIH for an aggregate purchase price of approximately $613.5 million . On August 10, 2017, the Company issued an additional 1,666,666 shares of its Class A Common Stock for an aggregate purchase price of $26.0 million and an additional 338,124 shares of its Class A Common Stock for an aggregate purchase price of $5.2 million . See Note 3 "Acquisition of KCG Holdings, Inc." for further details. Employee Exchanges In February 2017 and 2018, pursuant to the exchange agreement by and among the Company, Virtu Financial and holders of Virtu Financial common units, certain current and former employees elected to exchange 683,762 and 795,521 units, respectively, in Virtu Financial held directly or on their behalf by Virtu Employee Holdco LLC (“Employee Holdco”) on a one -for-one basis for shares of Class A common stock. As a result of the completion of the IPO, the Reorganization Transactions, the Secondary Offerings, employee exchanges, and the share issuance in connection with the Acquisition, the Company holds approximately 49.1% interest in Virtu Financial at March 31, 2018 .

Share-based Compensation

Share-based Compensation	3 Months Ended
	Mar. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-based Compensation	Share-based Compensation Share-based compensation prior to the Company’s Reorganization completed on April 15, 2015 and IPO commenced on April 16, 2015: During the period prior to the Company's Reorganization and IPO, Class A-2 profits interests were issued to Employee Holdco , a holding company that holds the interests on behalf of certain key employees or stakeholders. During the three months ended March 31, 2018 and 2017 , the Company recorded expense relating to non-voting common interest units, which were originally granted as Class A-2 profits interests and were reclassified into non-voting common interest units in connection with the Reorganization Transactions. The non-voting common interest units are subject to the same vesting requirements as the prior Class A-2 profits interests, which were either fully vested upon issuance or vested over a period of up to four years , and in each case are subject to repurchase provisions upon certain termination events. These awards were accounted for as equity awards and were measured at fair value at the date of grant. The Company recognized compensation expense related to the vesting of non-voting common interest units (formerly Class A-2 profits interests) of $0.0 million and $0.2 million for the three months ended March 31, 2018 and 2017 , respectively. As of March 31, 2018 and December 31, 2017 , total unrecognized share-based compensation expense related to unvested non-voting common interest units (formerly Class A-2 profits interests), was $0.0 million and $0.1 million , respectively; and this amount is expected to be recognized over a weighted average period of 0 and 0.1 years, respectively. Additionally, Class B interests were issued to Employee Holdco on behalf of certain key employees and stakeholders on various dates prior to the IPO. Class B interests were subject to time based vesting over four years and only fully vested upon the consummation of a qualifying capital transaction by the Company, including an IPO. In connection with the Reorganization Transactions, Class B Interests were reclassified into non-voting common interest units. The Company recognized compensation expense in respect of non-voting common interest units (formerly Class B interests) vested of $0 and $0.2 million for the three months ended March 31, 2018 and 2017 , respectively. The compensation expense related to non-voting common interest units (formerly Class B interests) was included within charges related to share based compensation at IPO in the condensed consolidated statements of comprehensive income. As of March 31, 2018 and December 31, 2017 , total unrecognized share-based compensation expense related to unvested non-voting common interest units (formerly Class B interests) was $0 and $0.1 million , respectively; and this amount is expected to be recognized over a weighted average period of 0 and 0.8 years, respectively. Additionally, in connection with the compensation charges related to non-voting common interest units (formerly Class B interests) mentioned above, the Company capitalized $0.00 million and $0.01 million for the three months ended March 31, 2018 and 2017 , respectively. The amortization costs related to these capitalized compensation charges and previously capitalized compensation charges related to East MIP Class B interests and Class B interests were approximately $0.01 million and $0.0 million for the three months ended March 31, 2018 and 2017 , respectively. The costs attributable to employees incurred in development of software for internal use were included within charges related to share based compensation at IPO in the condensed consolidated statements of comprehensive income. The fair value of the Class A-2 profit and Class B interest was estimated by the Company using an option pricing methodology based on expected volatility, risk-free rates and expected life. Expected volatility is calculated based on companies in the same peer group as the Company. In connection with the Reorganization Transactions, all Class A-2 profits interests and Class B interests were reclassified into non-voting common interest units. As of March 31, 2018 and December 31, 2017 , there were 11,512,297 and 12,301,067 non-voting common interest units outstanding, respectively, and 788,770 and 729,272 non-voting common interest units and corresponding Class C common stock were exchanged into Class A common stock, forfeited or repurchased during the three months ended March 31, 2018 and 2017 , respectively. Share-based compensation after the Company’s Reorganization completed on April 15, 2015 and IPO completed on April 16, 2015: Pursuant to 2015 Management Incentive Plan as described in Note 16 "Capital structure" , and in connection with the IPO, non-qualified stock options to purchase shares of Class A common stock were granted, each of which vests in equal annual installments over a period of the four years from grant date and expires not later than 10 years from the date of grant. The following table summarizes activity related to stock options for the three months ended March 31, 2018 and 2017 : Options Outstanding Options Exercisable Number of Options Weighted Average Exercise Price Per Share Weighted Average Remaining Contractual Life Number of Options Weighted Average Exercise Price Per Share December 31, 2016 8,234,000 $ 19.00 8.29 2,058,500 $ 19.00 Granted — — — — — Exercised — — — — — Forfeited or expired (195,000 ) — — — — March 31, 2017 8,039,000 $ 19.00 8.05 2,009,750 $ 19.00 December 31, 2017 7,783,000 $ 19.00 7.29 3,891,500 $ 19.00 Granted — — — — — Exercised (732,000 ) 19.00 — (732,000 ) 19.00 Forfeited or expired — — — — — March 31, 2018 7,051,000 $ 19.00 7.05 3,182,000 $ 19.00 The expected life has been determined based on an average of vesting and contractual period. The risk-free interest rate was determined based on the yields available on U.S. Treasury zero-coupon issues. The expected stock price volatility was determined based on historical volatilities of comparable companies. The expected dividend yield was determined based on estimated future dividend payments divided by the IPO stock price. The Company recognized $1.4 million and $1.4 million of compensation expense in relation to the stock options issued and outstanding for the three months ended March 31, 2018 and 2017 , respectively. As of March 31, 2018 and December 31, 2017 , total unrecognized share-based compensation expense related to unvested stock options was $6.1 million and $7.5 million , respectively, and these amounts are to be recognized over a weighted average period of 1.1 and 1.3 years, respectively. Class A common stock and Restricted Stock Units Pursuant to the 2015 Management Incentive Plan as described in Note 16 "Capital structure" , subsequent to the IPO, shares of immediately vested Class A common stock and restricted stock units were granted, the latter which vest over a period of up to 4 years . The fair value of the Class A common stock and RSUs was determined based on a volume weighted average price and is being recognized on a straight line basis over the vesting period. For the three months ended March 31, 2018 , there were 594,536 shares of immediately vested Class A common stock granted as part of 2017 year-end compensation, with a fair value of $11.3 million which was recorded as an increase to the condensed consolidated statements of changes in equity. In addition, the Company accrued compensation expense of $3.9 million and $4.7 million for the three months ended March 31, 2018 and 2017 related to immediately vested Class A common stock expected to be awarded as part of year-end incentive compensation, which was included in employee compensation and payroll taxes on the condensed consolidated statements of comprehensive income and accounts payable and accrued expenses and other liabilities on the condensed consolidated statements of financial condition. The following table summarizes activity related to the RSUs: Number of Shares Weighted Average Fair Value At December 31, 2016 1,573,441 $ 18.28 Granted — — Forfeited (95,481 ) 18.38 Vested — — At March 31, 2017 1,477,960 $ 18.28 At December 31, 2017 853,047 $ 17.94 Granted 1,044,690 20.64 Forfeited (30,626 ) 18.52 Vested — — At March 31, 2018 1,867,111 $ 18.85 The Company recognized $4.0 million and $2.6 million of compensation expense in relation to the restricted stock units for the three months ended March 31, 2018 and 2017 , respectively. As of March 31, 2018 and December 31, 2017 , total unrecognized share-based compensation expense related to unvested RSUs was $34.8 million and $14.3 million , respectively, and this amount is to be recognized over a weighted average period of 1.9 and 1.5 , respectively.

Regulatory Requirement

Regulatory Requirement	3 Months Ended
	Mar. 31, 2018
Regulatory Capital Requirements [Abstract]
Regulatory Requirement	Regulatory Requirement As of March 31, 2018 and December 31, 2017 , broker-dealer subsidiaries of the Company are subject to the SEC Uniform Net Capital Rule 15c3-1, which requires the maintenance of minimum net capital of $1.0 million for each of the three broker-dealer subsidiaries. Pursuant to NYSE and NYSE MKT (formerly NYSE Amex) rules, Virtu Financial Capital Markets LLC was also required to maintain $3.7 million and $4.1 million of capital in connection with the operation of its designated market maker (“DMM”) business as of March 31, 2018 and December 31, 2017 , respectively. The required amount is determined under the exchange rules as the greater of $1 million or 15% of the market value of 60 trading units for each symbol in which the broker-dealer subsidiary is registered as the DMM. The regulatory capital and regulatory capital requirements of these subsidiaries as of March 31, 2018 was as follows: (in thousands) Regulatory Capital Regulatory Capital Requirement Excess Regulatory Capital Virtu Americas LLC $ 411,168 $ 1,000 $ 410,168 Virtu Financial BD LLC 88,280 1,000 87,280 Virtu Financial Capital Markets LLC 8,563 4,696 3,867 The regulatory capital and regulatory capital requirements of these subsidiaries as of December 31, 2017 was as follows: (in thousands) Regulatory Capital Regulatory Capital Requirement Excess Regulatory Capital Virtu Americas LLC $ 379,875 $ 1,000 $ 378,875 Virtu Financial BD LLC 40,683 1,000 39,683 Virtu Financial Capital Markets LLC 8,308 5,114 3,194

Geographic Information and Busi

Geographic Information and Business Segments	3 Months Ended
	Mar. 31, 2018
Segment Reporting [Abstract]
Geographic Information and Business Segments	Geographic Information and Business Segments The Company operates its business in the U.S. and internationally, primarily in Europe and Asia. Significant transactions and balances between geographic regions occur primarily as a result of certain Company’s subsidiaries incurring operating expenses such as employee compensation, communications and data processing and other overhead costs, for the purpose of providing execution, clearing and other support services to affiliates. Charges for transactions between regions are designed to approximate full costs. Intra-region income and expenses and related balances have been eliminated in the geographic information presented below to accurately reflect the external business conducted in each geographical region. The revenues are attributed to countries based on the locations of the subsidiaries. The following table presents total revenues by geographic area for the three months ended March 31, 2018 and 2017 : (in thousands) 2018 2017 Revenues: United States $ 743,152 $ 91,987 Ireland 14,023 28,251 United Kingdom 11,600 — Singapore 46,200 27,006 Others 78 43 Total revenues 815,053 147,287 Prior to the Acquisition, the Company was managed and operated as one business, and, accordingly, operated under one reportable segment. As a result of the acquisition of KCG, beginning in the third quarter of 2017 the Company has three operating segments: (i) Market Making; (ii) Execution Services; and (iii) Corporate. The Market Making segment principally consists of market making in the cash, futures and options markets across global equities, options, fixed income, currencies and commodities. As a market maker, the Company commits capital on a principal basis by offering to buy securities from, or sell securities to, broker dealers, banks and institutions. The Company engages in principal trading in the Market Making segment direct to clients as well as in a supplemental capacity on exchanges, ECNs and alternative trading systems ATSs. The Company is an active participant on all major global equity and futures exchanges and also trades on substantially all domestic electronic options exchanges. As a complement to electronic market making, the cash trading business handles specialized orders and also transacts on the OTC Bulletin Board marketplaces operated by the OTC Markets Group Inc. and the AIM. The Execution Services segment comprises agency-based trading and trading venues, offering execution services in global equities, options, futures and fixed income on behalf of institutions, banks and broker dealers as well as technology services revenues. The Company earns commissions and commission equivalents as an agent on behalf of clients as well as between principals to transactions; in addition, the Company will commit capital on behalf of clients as needed. Agency-based, execution-only trading in the segment is done primarily through a variety of access points including: (i) algorithmic trading and order routing in global equities and options; (ii) institutional sales traders executing program, block and riskless principal trades in global equities and ETFs; (iii) a fixed income ECN that also offers trading applications; and (iv) an ATS for U.S. equities. Technology licensing fees are earned from third parties for licensing of the Company’s proprietary risk management and trading infrastructure technology and the provision of associated management and hosting services. The Corporate segment contains the Company's investments, principally in strategic trading-related opportunities and maintains corporate overhead expenses and all other income and expenses that are not attributable to the Company's other segments. Management evaluates the performance of its segments on a pre-tax basis. Segment assets and liabilities are not used for evaluating segment performance or in deciding how to allocate resources to segments. The Company’s total revenues and income before income taxes and noncontrolling interest (“Pre-tax earnings”) by segment for the three months ended March 31, 2018 and 2017 are summarized in the following table: (in thousands) Market Making Execution Services Corporate (1) Consolidated Total 2018: Total revenue $ 432,536 $ 383,779 $ (1,262 ) $ 815,053 Income before income taxes and noncontrolling interest 163,163 331,185 (25,812 ) 468,536 2017: Total revenue $ 144,448 $ 2,779 $ 60 $ 147,287 Income (loss) before income taxes and noncontrolling interest 23,465 489 (72 ) 23,882 (1) Amounts shown in the Corporate segment include eliminations of income statement and balance sheet items included in the Company's other segments.

Related Party Transactions

Related Party Transactions	3 Months Ended
	Mar. 31, 2018
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions The Company incurs expenses and maintains balances with its affiliates in the ordinary course of business. As of March 31, 2018 , and December 31, 2017 the Company had a receivable of $1.3 million and a receivable of $0.1 million to its affiliates, respectively. The Company conducts securities lending transactions with Industrial and Commercial Bank of China (“ICBC”), which is partially owned by Temasek and its affiliates. As of March 31, 2018 , the Company had a securities loaned contract of $0.7 million with ICBC. The Company had a securities borrowed contract of $23.1 million and a securities loaned contract of $1.1 million outstanding with ICBC as of December 31, 2017 . The Company purchases network connections services from affiliates of Level 3 Communications (“Level 3”). Temasek and its affiliates have a significant ownership interest in Level 3. For the three months ended March 31, 2018 and 2017 , the Company paid $0.7 million and $0.7 million , respectively, to Level 3 for these services. The Company purchases and leases computer equipment and maintenance and support from affiliates of Dell Inc. (“Dell”). Temasek and its affiliates have a significant ownership interest in Dell. For the three months ended March 31, 2018 and 2017 , the Company paid $0.6 million and $0.8 million , respectively, to Dell for these purchases and leases. The Company purchases market data and software licenses from affiliates of Markit Group Holdings Limited (“MarkIt”). Temasek and its affiliates have a significant ownership interest in MarkIt. For the three months ended March 31, 2018 , the Company paid $0.4 million to MarkIt for these services. The amount paid to MarkIt was immaterial for the three months ended March 31, 2017 . The Company has held a minority interest in SBI since 2016 (See Note 11 "Financial assets and liabilities" ). The Company pays exchange fees to SBI for the trading activities conducted on its proprietary trading system. The Company paid $2.3 million and $1.5 million for the three months ended March 31, 2018 and for the period since the completion of the minority interest investment to March 31, 2017 , respectively. The Company makes payments to two JVs (See Note 2, “Summary of Significant Accounting Policies”) to fund the construction of the microwave communication networks, and to purchase microwave communication networks, which are recorded within communications and data processing on the condensed consolidated statements of comprehensive income. The Company made payments of $5.6 million and $0.1 million to the JVs for the three months ended March 31, 2018 and 2017 , respectively.

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events The Company has evaluated subsequent events for adjustment to or disclosure in its condensed consolidated financial statements through the date of this report, and has not identified any recordable or disclosable events, not otherwise reported in these condensed consolidated financial statements or the notes thereto, except for the following: On April 13, 2018, the Company received $39.3 million tax distribution from Virtu Financial. On April 19, 2018, the Company prepaid $100.0 million of principal under its Fourth Amended and Restated Credit Agreement, as amended. The total principal outstanding under the senior secured facility is $524.0 million . On May 4, 2018, the Company’s board of directors declared a dividend of $0.24 per share of Class A common stock and Class B common stock and per Restricted Stock Unit that will be paid on June 15, 2018 to holders of record as of June 1, 2018.

Summary of Significant Accoun28

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2018
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates The Company's condensed consolidated financial statements are prepared in conformity with U.S. GAAP, which require management to make estimates and assumptions regarding measurements including the fair value of trading assets and liabilities, goodwill and intangibles, compensation accruals, capitalized software, income tax, and other matters that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. Accordingly, actual results could differ materially from those estimates.
Earnings Per Share	Earnings Per Share Earnings per share (“EPS”) is calculated on both a basic and diluted basis. Basic EPS excludes dilution and is calculated by dividing income available to common stockholders by the weighted-average number of common shares outstanding for the period. Diluted EPS is calculated by dividing the net income available for common stockholders by the diluted weighted average shares outstanding for that period. Diluted EPS includes the determinants of the basic EPS and, in addition, reflects the dilutive effect of shares of common stock estimated to be distributed in the future under the Company’s share based compensation plans. The Company grants restricted stock units (“RSUs”), which entitle recipients to receive nonforfeitable dividends during the vesting period on a basis equivalent to the dividends paid to holders of common stock. As a result, the unvested RSUs meet the definition of a participating security requiring the application of the two-class method. Under the two-class method, earnings available to common shareholders, including both distributed and undistributed earnings, are allocated to each class of common stock and participating securities according to dividends declared and participating rights in undistributed earnings, which may cause diluted EPS to be more dilutive than the calculation using the treasury stock method.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents include money market accounts, which are payable on demand, and short-term investments with an original maturity of less than 90 days. The Company maintains cash in bank deposit accounts that, at times, may exceed federally insured limits. The Company manages this risk by selecting financial institutions deemed highly creditworthy to minimize the risk.
Securities Borrowed and Securities Loaned	Securities Borrowed and Securities Loaned The Company conducts securities borrowing and lending activities with external counterparties. In connection with these transactions, the Company receives or posts collateral, which comprises cash and/or securities. In accordance with substantially all of its stock borrow agreements, the Company is permitted to sell or repledge the securities received. Securities borrowed or loaned are recorded based on the amount of cash collateral advanced or received. The initial cash collateral advanced or received generally approximates or is greater than 102% of the fair value of the underlying securities borrowed or loaned. The Company monitors the fair value of securities borrowed and loaned, and delivers or obtains additional collateral as appropriate. Receivables and payables with the same counterparty are not offset in the condensed consolidated statements of financial condition. Interest received or paid by the Company for these transactions is recorded gross on an accrual basis under interest and dividends income or interest and dividends expense in the condensed consolidated statements of comprehensive income.
Securities Purchased Under Agreements to Resell and Securities Sold Under Agreements to Repurchase	Securities Purchased Under Agreements to Resell and Securities Sold Under Agreements to Repurchase In a repurchase agreement, securities sold under agreements to repurchase are treated as collateralized financing transactions and are recorded at contract value, plus accrued interest, which approximates fair value. It is the Company's policy that its custodian takes possession of the underlying collateral securities with a fair value approximately equal to the principal amount of the repurchase transaction, including accrued interest. For reverse repurchase agreements, the Company typically requires delivery of collateral with a fair value approximately equal to the carrying value of the relevant assets in the condensed consolidated statements of financial condition. To ensure that the fair value of the underlying collateral remains sufficient, the collateral is valued daily with additional collateral obtained or excess collateral returned, as permitted under contractual provisions. The Company does not net securities purchased under agreements to resell transactions with securities sold under agreements to repurchase transactions entered into with the same counterparty. The Company has also entered into bilateral and tri-party term and overnight repurchase and other collateralized financing agreements which bear interest at negotiated rates. The Company receives cash and makes delivery of financial instruments to a custodian who monitors the market value of these instruments on a daily basis. The market value of the instruments delivered must be equal to or in excess of the principal amount loaned under the repurchase agreements plus the agreed upon margin requirement. The custodian may request additional collateral, if appropriate. Interest received or paid by the Company for these transactions is recorded gross on an accrual basis under interest and dividends income or interest and dividends expense in the condensed consolidated statements of comprehensive income.
Receivables from/Payables to Broker-dealers and Clearing Organizations	Receivables from/Payables to Broker-dealers and Clearing Organizations Amounts receivable from broker-dealers and clearing organizations may be restricted to the extent that they serve as deposits for securities sold, not yet purchased. At March 31, 2018 and December 31, 2017 , receivables from and payables to broker-dealers and clearing organizations primarily represented amounts due for unsettled trades, open equity in futures transactions, securities failed to deliver or failed to receive, deposits with clearing organizations or exchanges and balances due from or due to prime brokers in relation to the Company’s trading. The Company presents its balances, including outstanding principal balances on all credit facilities, on a net by counterparty basis within receivables from and payable to broker-dealers and clearing organizations when the criteria for offsetting are met. In the normal course of business, a significant portion of the Company’s securities transactions, money balances, and security positions are transacted with several third-party brokers. The Company is subject to credit risk to the extent any broker with whom it conducts business is unable to fulfill contractual obligations on its behalf. The Company monitors the financial condition of such brokers and to minimize the risk of any losses from these counterparties.
Financial Instruments Owned Including Those Pledged as Collateral and Financial Instruments Sold, Not Yet Purchased	Financial Instruments Owned Including Those Pledged as Collateral and Financial Instruments Sold, Not Yet Purchased Financial instruments owned and Financial instruments sold, not yet purchased relate to market making and trading activities, and include listed and other equity securities, listed equity options and fixed income securities. The Company records financial instruments owned, including those pledged as collateral, and financial instruments sold, not yet purchased at fair value. Gains and losses arising from financial instrument transactions are recorded net on a trade-date basis in trading income, net, in the condensed consolidated statements of comprehensive income.
Fair Value Measurements	Fair Value Measurements Fair value is defined as the price that would be received to sell an asset or would be paid to transfer a liability (i.e., the exit price) in an orderly transaction between market participants at the measurement date. Fair value measurements are not adjusted for transaction costs. The recognition of “block discounts” for large holdings of unrestricted financial instruments where quoted prices are readily and regularly available in an active market is prohibited. The Company categorizes its financial instruments into a three level hierarchy which prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy level assigned to each financial instrument is based on the assessment of the transparency and reliability of the inputs used in the valuation of such financial instruments at the measurement date based on the lowest level of input that is significant to the fair value measurement. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (level 1 measurement) and the lowest priority to unobservable inputs (level 3 measurements). Financial instruments measured and reported at fair value are classified and disclosed in one of the following categories based on inputs: Level 1 — Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities; Level 2 — Quoted prices in markets that are not active and financial instruments for which all significant inputs are observable, either directly or indirectly; or Level 3 — Prices or valuations that require inputs that are both significant to the fair value measurement and unobservable. Transfers in or out of levels are recognized based on the beginning fair value of the period in which they occurred.
Fair Value Option	Fair Value Option The fair value option election allows entities to make an irrevocable election of fair value as the initial and subsequent measurement attribute for certain eligible financial assets and liabilities. Unrealized gains and losses on items for which the fair value option has been elected are recorded in other, net in the condensed consolidated statements of comprehensive income. The decision to elect the fair value option is determined on an instrument by instrument basis, which must be applied to an entire instrument and is irrevocable once elected.
Derivative Instruments	Derivative Instruments Derivative instruments are used for trading purposes, including economic hedges of trading instruments, which are carried at fair value include futures, forward contracts, and options. Gains or losses on these derivative instruments are recognized currently within trading income, net in the condensed consolidated statement of comprehensive income. Fair values for exchange-traded derivatives, principally futures, are based on quoted market prices. Fair values for over-the-counter derivative instruments, principally forward contracts, are based on the values of the underlying financial instruments within the contract. The underlying instruments are currencies, which are actively traded. The Company presents its derivatives balances on a net-by-counterparty basis when the criteria for offsetting are met.
Property, Equipment and Occupancy	Property, Equipment and Occupancy Property and equipment are carried at cost, less accumulated depreciation, except for the assets acquired in connection with acquisitions using the purchase accounting method, which were recorded at fair value on the respective date of acquisitions. Depreciation is provided using the straight-line method over estimated useful lives of the underlying assets. Routine maintenance, repairs and replacement costs are expensed as incurred and improvements that appreciably extend the useful life of the assets are capitalized. When property and equipment are sold or otherwise disposed of, the cost and related accumulated depreciation are removed from the accounts and any resulting gain or loss is recognized in income. Property and equipment are reviewed for impairment whenever events or changes in circumstances indicate that the related carrying amount may not be recoverable. Furniture, fixtures, and equipment are depreciated over three to seven years. Leasehold improvements are amortized over the lesser of the life of the improvement or the term of the lease. The Company recognizes rent expense under operating leases with fixed rent escalations, lease incentives and free rent periods on a straight-line basis over the lease term beginning on the date the Company takes possession of or controls the use of the space, including during free rent periods.
Lease Loss Accrual	Lease Loss Accrual The Company’s policy is to identify excess real estate capacity and where applicable, accrue for related future costs, net of projected sub-lease income upon the date the Company ceases to use the excess real estate, which is recorded under operating and administrative in the condensed consolidated statements of comprehensive income. Such accrual is adjusted to the extent the actual terms of sub-leased property differ from the previous assumptions used in the calculation of the accrual.
Capitalized Software	Capitalized Software The Company capitalizes costs of materials, consultants, and payroll and payroll related costs for employees incurred in developing internal-use software. Costs incurred during the preliminary project and post-implementation stages are charged to expense. Management’s judgment is required in determining the point at which various projects enter the stages at which costs may be capitalized, in assessing the ongoing value of the capitalized costs, and in determining the estimated useful lives over which the costs are amortized. Capitalized software development costs and related accumulated amortization are included in property, equipment and capitalized software in the accompanying condensed consolidated statements of financial condition and are amortized over a period of 1.5 to 2.5 years , which represents the estimated useful lives of the underlying software.
Goodwill	Goodwill Goodwill represents the excess of the purchase price over the underlying net tangible and intangible assets of the Company’s acquisitions. Goodwill is not amortized but is tested for impairment on an annual basis and between annual tests whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. Goodwill is tested at the reporting unit level, which is defined as an operating segment or one level below the operating segment. The Company tests goodwill for impairment on an annual basis on July 1 and on an interim basis when certain events or circumstances exist. In the impairment test as of July 1, 2017, the primary valuation method used to estimate the fair value of the Company’s reporting unit was the market capitalization approach based on the market price of its Class A common stock, which the Company’s management believes to be an appropriate indicator of its fair value. Following the Acquisition, our impairment testing is performed for each reporting unit.
Intangible Assets	Intangible Assets The Company amortizes finite-lived intangible assets over their estimated useful lives. Finite-lived intangible assets are tested for impairment annually or when impairment indicators are present, and if impaired, they are written down to fair value.
Exchange Memberships and Stock	Exchange Memberships and Stock Exchange memberships are recorded at cost or, if any other than temporary impairment in value has occurred, at a value that reflects management’s estimate of fair value. Exchange memberships acquired in connection with the Acquisition were recorded at their fair value on the date of acquisition. Exchange stock includes shares that entitle the Company to certain trading privileges. The Company’s exchange memberships and stock are included in intangibles in the condensed consolidated statements of financial condition.
Trading Income, net	Trading Income, net Trading income, net is comprised of changes in the fair value of trading assets and liabilities (i.e., unrealized gains and losses) and realized gains and losses on trading assets and liabilities. Trading gains and losses on financial instruments owned and financial instruments sold, not yet purchased are recorded on the trade date and reported on a net basis in the condensed consolidated statements of comprehensive income. The Company recognizes the related revenue when the third party research services are rendered and payments are made.
Commissions, net and Technology Services	Commissions, net and Technology Services Commissions, net, which primarily comprise commissions and commission equivalents earned on institutional client orders, are recorded on a trade date basis. Under a commission management program, the Company allows institutional clients to allocate a portion of their gross commissions to pay for research and other services provided by third parties. As the Company acts as an agent in these transactions, it records such expenses on a net basis within Commissions and technology services in the condensed consolidated statements of comprehensive income. Technology services revenues consist of technology licensing fees and agency commission fees. Technology licensing fees are earned from third parties for licensing of the Company’s proprietary risk management and trading infrastructure technology and the provision of associated management and hosting services. These fees include both upfront and annual recurring fees, as well as, in certain cases, contingent fees based on client revenues, which represent variable consideration. The services offered under these contracts have the same pattern of transfer; accordingly, they are being measured and recognized as a single performance obligation. The performance obligation is satisfied over time, and accordingly, revenue is recognized as time passes. Variable consideration has not been included in the transaction price as the amount of consideration is contingent on factors outside the Company’s control and thus it is not probable that a significant reversal of cumulative revenue recognized will not occur. Recurring fees, which exclude variable consideration, are billed and collected on a quarterly basis.
Interest and Dividends Income/Interest and Dividends Expense	Interest and Dividends Income/Interest and Dividends Expense Interest income and interest expense are accrued in accordance with contractual rates. Interest income consists of interest earned on collateralized financing arrangements and on cash held by brokers. Interest expense includes interest expense from collateralized transactions, margin and related lines of credit. Dividends on financial instruments owned including those pledged as collateral and financial instruments sold, not yet purchased are recorded on the ex-dividend date and interest is recognized on an accrual basis.
Brokerage, Exchange and Clearance Fees, Net	Brokerage, Exchange and Clearance Fees, Net Brokerage, exchange and clearance fees, net, comprise the costs of executing and clearing trades and are recorded on a trade date basis. Rebates consist of volume discounts, credits or payments received from exchanges or other market places related to the placement and/or removal of liquidity from the order flow in the marketplace. Rebates are recorded on an accrual basis and included net within brokerage, exchange and clearance fees in the accompanying condensed consolidated statements of comprehensive income.
Payments for Order Flow	Payments for Order Flow Payments for order flow represent payments to broker-dealer clients, in the normal course of business, for directing their order flow in U.S. equities to the Company. Payments for order flow are recorded on a trade-date basis in the condensed consolidated statements of comprehensive income.
Income Taxes	Income Taxes Subsequent to consummation of the Reorganization Transactions and the IPO, the Company is subject to U.S. federal, state and local income taxes on its taxable income. The Company's subsidiaries are subject to income taxes in the respective jurisdictions (including foreign jurisdictions) in which they operate. Prior to the consummation of the Reorganization Transactions and the IPO, no provision for United States federal, state and local income tax was required, as Virtu Financial is a limited liability company and is treated as a pass-through entity for United States federal, state, and local income tax purposes. The provision for income tax is comprised of current tax and deferred tax. Current tax represents the tax on current year tax returns, using tax rates enacted at the balance sheet date. The deferred tax assets are recognized in full and then reduced by a valuation allowance if it is more likely than not that some or all of the deferred tax assets will not be recognized. The Company recognizes the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained on examination by the applicable taxing authority, including resolution of the appeals or litigation processes, based on the technical merits of the position. The tax benefits recognized in the condensed consolidated financial statements from such a position are measured based on the largest benefit for each such position that has a greater than fifty percent likelihood of being realized upon ultimate resolution. Many factors are considered when evaluating and estimating the tax positions and tax benefits. Such estimates involve interpretations of regulations, rulings, case law, etc. and are inherently complex. The Company’s estimates may require periodic adjustments and may not accurately anticipate actual outcomes as resolution of income tax treatments in individual jurisdictions typically would not be known for several years after completion of any fiscal year. Public Law No. 115-97, commonly referred to as The Tax Cuts and Jobs Act (the “2017 Tax Act”) was signed into law on December 22, 2017. The 2017 Tax Act significantly changes how the U.S. federal government taxes corporations and requires significant judgments to be made in interpretation of its provisions and significant estimates in calculations, and the preparation and analysis of information not previously relevant or regularly produced. The U.S. Treasury Department, the IRS, and other standard-setting bodies could interpret or issue guidance on how provisions of the 2017 Tax Act will be applied or otherwise administered that is different from our interpretation. As we complete our analysis of the 2017 Tax Act, collect and prepare necessary data, and interpret any additional guidance, we may make adjustments to provisional amounts that we have recorded that may materially impact our provision for income taxes in the period in which the adjustments are made. See Note 14 “Income Taxes”.
Comprehensive Income (Loss) and Foreign Currency Translation	Comprehensive Income and Foreign Currency Translation Comprehensive income consists of two components: net income and other comprehensive income (“OCI”). The Company’s OCI is comprised of foreign currency translation adjustments. Assets and liabilities of operations having non-U.S. dollar functional currencies are translated at period-end exchange rates, and revenues and expenses are translated at weighted average exchange rates for the period. Gains and losses resulting from translating foreign currency financial statements, net of related tax effects, are reflected in accumulated other comprehensive income, a separate component of stockholders’ equity. The Company's foreign subsidiaries generally use the U.S. dollar as their functional currency. The Company also has subsidiaries that utilize a functional currency other than the U.S. dollar, primarily comprising its subsidiaries domiciled in Ireland, which utilizes the Euro as the functional currency. The Company may seek to reduce the impact of fluctuations in foreign exchange rates on its net investment in certain non-U.S. operations through the use of foreign currency forward contracts. For foreign currency forward contracts designated as hedges, the Company assesses its risk management objectives and strategy, including identification of the hedging instrument, the hedged item and the risk exposure and how effectiveness is to be assessed prospectively and retrospectively. The effectiveness of the hedge is assessed based on the overall changes in the fair value of the forward contracts. For qualifying net investment hedges, any gains or losses, to the extent effective, are included in Accumulated other comprehensive income on the condensed consolidated statements of financial condition and Cumulative translation adjustment, net of tax, on the condensed consolidated statements of comprehensive income. The ineffective portion, if any, is recorded in Investment income and other, net on the condensed consolidated statements of operations.
Share-Based Compensation	Share-Based Compensation The fair value of awards issued for compensation prior to the Reorganization Transactions and the IPO was determined by management, with the assistance of an independent third party valuation firm, using a projected annual forfeiture rate, where applicable, on the date of grant. Share-based awards issued for compensation in connection with or subsequent to the Reorganization Transactions and the IPO pursuant to the VFI 2015 Management Incentive Plan (as amended, the “2015 Amended and Restated Management Incentive Plan”) were in the form of stock options, Class A common stock and RSUs. The fair value of the stock option grants is determined through the application of the Black-Scholes-Merton model. The fair value of the Class A common stock and RSUs are determined based on the volume weighted average price for the three days preceding the grant, and with respect to the RSUs, a projected annual forfeiture rate. The fair value of share-based awards granted to employees is expensed based on the vesting conditions and are recognized on a straight line basis over the vesting period. The Company records as treasury stock shares repurchased from its employees for the purpose of settling tax liabilities incurred upon the issuance of Class A common stock, the vesting of RSUs or the exercise of stock options.
Variable Interest Entity	Variable Interest Entities A variable interest entity (“VIE”) is an entity that lacks one or more of the following characteristics (i) the total equity investment at risk is sufficient to enable the entity to finance its activities independently and (ii) the equity holders have the power to direct the activities of the entity that most significantly impact its economic performance, the obligation to absorb the losses of the entity and the right to receive the residual returns of the entity. The Company will be considered to have a controlling financial interest and will consolidate a VIE if it has both (i) the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance and (ii) the obligation to absorb losses of the VIE or the right to receive benefits from the VIE that could potentially be significant to the VIE. In October 2016, the Company invested in a joint venture (“JV”) with nine other parties. One of the parties was KCG. Upon the Merger, KCG was required to relinquish their ownership in the JV. As of March 31, 2018 , each of the remaining parties owns approximately 11% of the voting shares and 11% of the equity of this JV, which is building microwave communication networks in the U.S. and Asia, and which is considered to be a VIE. The Company and all of its JV partners each pay monthly fees for the funding of the construction of the microwave communication networks. When completed, this JV may sell excess bandwidth that is not utilized by its joint venture members to third parties. In addition, as a result of the Acquisition, the Company owns 50% of the voting shares and 50% of the equity of a JV which maintains microwave communication networks in the U.S. and Europe, and which is considered to be a VIE. The Company and its JV partner each pay monthly fees for the use of the microwave communication networks in connection with their respective trading activities, and the JV may sell excess bandwidth that is not utilized by the JV members to third parties. In each of the JVs, the Company does not have the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance; therefore it does not have a controlling financial interest in the JV and does not consolidate the JVs. The Company records its interest in each JV under the equity method of accounting and records its investment in the JVs within Other assets and its amounts payable for communication services provided by the JV within Accrued expenses and other liabilities on the condensed consolidated statements of financial condition. The Company records its pro-rata share of each JVs earnings or losses within Other, net and fees related to the use of communication services provided by the JVs within Communications and data processing on the condensed consolidated statements of comprehensive income.
Recent Accounting Pronouncements	Recent Accounting Pronouncements Revenue - In May 2014, the FASB issued Accounting Standard Update (“ASU”) 2014-9, Revenue from Contracts with Customers . ASU 2014-9 is a comprehensive new revenue recognition model that requires a company to recognize revenue to depict the transfer of goods or services to a customer at an amount that reflects the consideration it expects to receive in exchange for those goods or services. ASU 2014-9 also requires additional disclosure about the nature, amount, timing and uncertainty of revenue and cash flows arising from customer contracts, including significant judgments and changes in judgments and assets recognized from costs incurred to obtain or fulfill a contract. In August 2015, the FASB issued ASU 2015-14, Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date . ASU 2015-14 defers the effective date of ASU 2014-9 by one year for public companies. ASU 2015-14 applies to annual reporting periods beginning after December 15, 2017, including interim reporting periods within that reporting period. In December 2016, FASB issued ASU 2016-20T echnical Correction and Improvement (Topic 606): Revenue from Contracts with Customers , which amends the guidance in ASU 2014-9. The effective date and transition requirements for the ASU are the same as ASU 2015-14. The Company adopted the new revenue standard on January 1, 2018 by applying the modified retrospective method, which did not result in a transition adjustment. The new standard does not apply to revenue associated with financial instruments that are accounted for under other U.S. GAAP, and as a result, did not have an impact on the Company’s condensed consolidated statements of comprehensive income, which are most closely associated with financial instruments, including trading income, net, and interest and dividends income. The new revenue standard primarily impacts revenues from technology services, commissions and soft-dollar arrangements generated by execution services. The additional disclosures required by the new standard have been included in Note 13 "Revenues from contracts with customers" . Financial Assets and Liabilities — In January 2016, the FASB issued ASU 2016-01, Financial Instruments – Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities . The ASU affects the accounting for equity investments, financial liabilities under fair value option and presentation and disclosure requirements of financial instruments. The new ASU affects all entities that hold financial assets or owe financial liabilities and is effective for annual reporting periods (including interim periods) beginning after December 15, 2017. The Company does not currently classify any equity securities as available for sale, and it does not apply the fair value option to its own debt issuances. The Company has adopted this ASU as of March 31, 2018, and it did not have a material impact on its condensed consolidated financial statements. Leases — In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) . Under the new ASU, a lessee will be required to recognize assets and liabilities for leases with lease terms of more than 12 months. The liability will be equal to the present value of the future lease payments. The asset, referred to as a “right-of-use asset” will be based on the liability, subject to adjustment, such as for initial direct costs. For income statement purposes, leases will be classified as either operating or finance. Operating leases will result in straight-line expense (similar to current operating leases) while finance leases will result in a front-loaded expense pattern (similar to current capital leases). Classification will be based on criteria that are largely similar to those applied in current lease accounting, but without explicit bright lines. The Company's implementation effort is on going, and it anticipates adopting this ASU on January 1, 2019. The Company is not anticipating recognizing lease assets and lease liabilities for leases with a term of twelve months or less. Upon adoption of this ASU, the Company expects to report increased assets and liabilities on its condensed consolidated statement of financial condition as a result of recognizing right-of-use assets and lease liabilities related to certain equipment under non-cancelable operating lease agreements and long-term occupancy operating leases, which currently are not reflected in its condensed consolidated statement of financial condition. Statement of Cash Flows – In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments. The ASU intended to reduce diversity in practice how certain transactions are classified in the statement of cash flows by mandating classification of certain activities. The ASU is effective for annual periods beginning after December 15, 2017, and interim periods within those annual periods. The Company has adopted this ASU as of June 30, 2017, and it did not have a material impact on its condensed consolidated statement of cash flows. Income Taxes – In October 2016, the FASB issued ASU 2016-16, Income Taxes (Topic 749): Intra-Entity Transfers of Assets Other Than Inventory . The ASU requires the reporting entity to recognize the tax expense from the sale of an asset in the seller’s tax jurisdiction when the transfer occurs, even though the pre-tax effects of the transactions are eliminated in consolidation. Any deferred tax asset that arises in the buyer’s jurisdiction would also be recognized at the time of the transfer. The ASU is effective for annual periods beginning after December 15, 2018, and interim reporting periods within annual reporting periods beginning after December 15, 2019. The Company is currently evaluating the potential effects of adoption of ASU 2016-16 on the Company’s condensed consolidated financial statements. Restricted cash – In November 2016, the FASB issued ASU 2016-18, Statement of Cash Flow (Topic 230): Restricted Cash , which is intended to reduce diversity in the presentation of restricted cash and restricted cash equivalents in the statements of financial conditions. The ASU requires that restricted cash and restricted cash equivalents be included as components of total cash and cash equivalents as presented on the statement of cash flows. This ASU is effective for annual reporting periods beginning after December 15, 2017, and interim periods within those fiscal years. The Company elected to early adopt this ASU effective June 30, 2017.The adoption of the ASU affected the presentation of the Company’s condensed consolidated statements of cash flows in periods in which it maintained restricted cash and restricted cash equivalents. Accounting Changes – In January 2017, the FASB issued ASU 2017-3, Accounting Changes and Error Correction (Topic 250) and Investments – Equity Method and Joint Ventures (Topic 323) , which amends SEC Paragraphs Pursuant to Staff Announcements at the September 22, 2016 and November 17, 2016 EITF Meetings (SEC update). The SEC staff view is that a registrant should evaluate the impact of new accounting standards that have not yet been adopted to determine the appropriate financial disclosures on the potential material effects, especially on new standards on revenue recognition, leases, and financial instruments – credit losses. If a registrant cannot reasonably estimate the impact that adoption of the ASUs will have, the registrant should consider additional qualitative financial statement disclosures to assist the reader in assessing the significance of the impact. Additional qualitative disclosures should include a description of the effect of the accounting policies expected to be applied compared to current accounting policies. Furthermore, the registrant should describe the status of its process to implement the new standards and the significant implementation matters yet to be addressed. The Company adopted this ASU on January 1, 2017, and appropriate disclosures have been included in this Note for each recently issued accounting standard. Goodwill - In January, 2017, the FASB issued ASU 2017-4, Intangibles—Goodwill and Other (Topic 350), Simplifying the Test for Goodwill Impairment . To simplify the subsequent measurement of goodwill, this ASU eliminated Step 2 from the goodwill impairment test. (In computing the implied fair value of goodwill under Step 2, an entity had to perform procedures to determine the fair value at the impairment testing date of its assets and liabilities (including unrecognized assets and liabilities) following the procedure that would be required in determining the fair value of assets acquired and liabilities assumed in a business combination. Instead, under this ASU, an entity should perform its annual, or interim, goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. An entity should recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. This ASU also eliminated the requirements for any reporting unit with a zero or negative carrying amount to perform a qualitative assessment and, if it fails that qualitative test, to perform Step 2 of the goodwill impairment test. This ASU is effective for public entities in fiscal years beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The Company does not expect the adoption of this ASU to have a material impact on its condensed consolidated financial statements. Business Combinations - In January 2017, the FASB issued ASU 2017-1, Business Combinations (Topic 805), Clarifying the Definition of a Business, to amend the definition of a business with the objective of adding guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. The ASU is effective for reporting periods beginning after December 15, 2017. The Company adopted this ASU on January 1, 2018.

Summary of Significant Accoun29

Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2018
Accounting Policies [Abstract]
Summary of nonconsolidated VIE	The following table presents the Company’s nonconsolidated VIE at March 31, 2018 : Carrying Amount Maximum Exposure to loss VIE's assets (in thousands) Asset Liability Equity investment $ 18,472 $ — $ 18,472 $ 51,344 The following table presents the Company’s nonconsolidated VIE at December 31, 2017 : Carrying Amount Maximum Exposure to VIE's assets (in thousands) Asset Liability Equity investment $ 18,799 $ — $ 18,799 $ 41,936

Acquisition of KCG Holdings, 30

Acquisition of KCG Holdings, Inc. (Tables)	3 Months Ended
	Mar. 31, 2018
Business Combinations [Abstract]
Schedule of Preliminary allocation of intangible assets, amortization period and goodwill	Amounts allocated to intangible assets, the amortization period and goodwill were as follows: (in thousands) Amount Amortization Years Technology $ 67,700 1-6 years Customer relationships 94,000 13 - 17 years Trade names 1,000 10 years Favorable leases 5,895 2-15 years Exchange memberships 6,400 Indefinite Intangible assets $ 174,995 Goodwill 128,286 Total $ 303,281

Sale of BondPoint (Tables)

Sale of BondPoint (Tables)	3 Months Ended
	Mar. 31, 2018
Discontinued Operations and Disposal Groups [Abstract]
Summary of assets and liabilities of businesses held for sale	A summary of the carrying value of BondPoint and gain on sale of BondPoint is as follows: (in thousand) Total sale proceeds received $ 400,192 Business assets and liabilities held for sale as of December 31, 2017: Receivables from broker dealers and clearing organizations 3,383 Intangibles and other assets 51,687 Liabilities (728 ) Total carrying value of BondPoint as of December 31, 2017: 54,342 Goodwill adjustment allocated to BondPoint 8,300 Gain on sale of BondPoint 337,550 Transaction costs 8,568 Gain on sale of BondPoint, net of transaction costs $ 328,982

Earnings per Share (Tables)

Earnings per Share (Tables)	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
Schedule of reconciliation of net income before noncontrolling interest to net income available for common stockholders	The below table contains a reconciliation of net income before noncontrolling interest to net income available for common stockholders: Three Months Ended March 31, (in thousands) 2018 2017 Income before income taxes and noncontrolling interest $ 468,536 $ 23,882 Provision for income taxes 58,514 2,808 Net income 410,022 21,074 Noncontrolling interest (235,271 ) (16,494 ) Net income available for common stockholders $ 174,751 $ 4,580
Schedule of basic earnings per share	The calculation of basic and diluted earnings per share is presented below: Three Months Ended March 31, (in thousands, except for share or per share data) 2018 2017 Basic earnings per share: Net income available for common stockholders $ 174,751 $ 4,580 Less: Dividends and undistributed earnings allocated to participating securities (3,213 ) (353 ) Net income available for common stockholders, net of dividends and undistributed earnings allocated to participating securities 171,538 4,227 Weighted average shares of common stock outstanding: Class A 90,699,321 40,398,381 Basic Earnings per share $ 1.89 $ 0.10
Schedule of diluted earnings per share	Three Months Ended March 31, (in thousands, except for share or per share data) 2018 2017 Diluted earnings per share: Net income available for common stockholders, net of dividends and undistributed earnings allocated to participating securities $ 171,538 $ 4,227 Weighted average shares of common stock outstanding: Class A Issued and outstanding 90,699,321 40,398,381 Issuable pursuant to 2015 Management Incentive Plan(1) 1,706,996 — 92,406,317 40,398,381 Diluted Earnings per share $ 1.86 $ 0.10 (1) The dilutive impact of unexercised stock options excludes from the computation of EPS 774,529 options for the three months ended March 31, 2017 , because inclusion of the options would have been anti-dilutive.

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of goodwill by segment	The following table presents the details of goodwill by segment: (in thousands) Market Making Execution Services Corporate Total Balance as of December 31, 2017 $ 755,292 $ 89,591 $ — $ 844,883 Goodwill adjustment allocated to BondPoint — (8,300 ) — (8,300 ) Balance as of March 31, 2018 $ 755,292 $ 81,291 $ — $ 836,583
Schedule of acquired intangible assets	Acquired intangible assets consisted of the following as of March 31, 2018 and December 31, 2017 : As of March 31, 2018 (in thousands) Gross Carrying Amount Accumulated Amortization Net Carrying Amount Useful Lives (Years) Purchased technology $ 110,000 $ 110,000 $ — 1.4 to 2.5 ETF issuer relationships 950 585 365 9 ETF buyer relationships 950 586 364 9 Leases 1,800 547 1,253 3 FCC licenses 200 26 174 7 Technology 60,000 15,047 44,953 1 to 6 Customer relationships 49,000 2,843 46,157 12 to 17 Favorable occupancy leases 5,895 612 5,283 7 Exchange memberships 5,838 — 5,838 Indefinite $ 234,633 $ 130,246 $ 104,387 As of December 31, 2017 (in thousands) Gross Carrying Amount Accumulated Amortization Net Carrying Amount Useful Lives Purchased technology $ 110,000 $ 110,000 $ — 1.4 to 2.5 ETF issuer relationships 950 559 391 9 ETF buyer relationships 950 560 390 9 Leases 1,800 397 1,403 3 FCC licenses 200 19 181 7 Technology 60,000 9,644 50,356 1 to 6 Customer relationships 49,000 1,822 47,178 12 to 17 Favorable occupancy leases 5,895 408 5,487 7 Exchange memberships 5,838 — 5,838 Indefinite $ 234,633 $ 123,409 $ 111,224

Receivables from_Payables to 34

Receivables from/Payables to Broker-Dealers and Clearing Organizations (Tables)	3 Months Ended
	Mar. 31, 2018
Due to and from Broker-Dealers and Clearing Organizations [Abstract]
Summary of receivables from and payables to brokers-dealers and clearing organizations	The following is a summary of receivables from and payables to brokers-dealers and clearing organizations at March 31, 2018 and December 31, 2017 : (in thousands) 2018 2017 Assets Due from prime brokers $ 153,716 $ 219,573 Deposits with clearing organizations 257,832 112,847 Net equity with futures commission merchants 308,964 203,711 Unsettled trades with clearing organization 430,514 173,778 Securities failed to deliver 271,287 248,088 Commissions and fees 11,726 14,021 Total receivables from broker-dealers and clearing organizations $ 1,434,039 $ 972,018 Liabilities Due to prime brokers $ 390,364 $ 197,439 Net equity with futures commission merchants 40,665 44,526 Unsettled trades with clearing organization 150,205 420,029 Securities failed to receive 65,715 51,143 Commissions and fees 1,839 3,068 Total payables to broker-dealers and clearing organizations $ 648,788 $ 716,205

Collateralized Transactions (Ta

Collateralized Transactions (Tables)	3 Months Ended
	Mar. 31, 2018
Collateralized Agreements [Abstract]
Summary of the fair value of collateralized transactions	he fair value of the collateralized transactions at March 31, 2018 and December 31, 2017 are summarized as follows: (in thousands) 2018 2017 Securities received as collateral: Securities borrowed $ 1,201,721 $ 1,415,793 $ 1,201,721 $ 1,415,793
Schedule of financial instruments owned and pledged, where counterparty has right to repledge	Financial instruments owned and pledged, where the counterparty has the right to repledge, at March 31, 2018 and December 31, 2017 consisted of the following: (in thousands) 2018 2017 Equities $ 571,997 $ 586,251 U.S. and Non-U.S. government obligations 200 99 Exchange traded notes 38,339 8,693 $ 610,536 $ 595,043

Borrowings (Tables)

Borrowings (Tables)	3 Months Ended
	Mar. 31, 2018
Debt Instrument [Line Items]
Outstanding borrowings and financing capacity or unused available capacity under the Company’s borrowing arrangements	The following summarizes the Company’s broker-dealer credit facilities carrying value, net of unamortized debt issuance costs, where applicable: At March 31, 2018 (in thousands) Interest Rate Financing Available Borrowing Outstanding Deferred Debt Issuance Cost Outstanding Borrowings, net Broker-dealer credit facilities: Uncommitted facility 2.68% $ 350,000 $ 17,500 $ (1,580 ) $ 15,920 Revolving credit facility 3.13% 500,000 7,000 (1,976 ) 5,024 $ 850,000 $ 24,500 $ (3,556 ) $ 20,944 At December 31, 2017 (in thousands) Interest Rate Financing Available Borrowing Outstanding Deferred Debt Issuance Cost Outstanding Borrowings, net Broker-dealer credit facilities: Uncommitted facility 2.42% $ 150,000 $ 25,000 $ — $ 25,000 Revolving credit facility 2.81% 500,000 7,000 (4,117 ) 2,883 $ 650,000 $ 32,000 $ (4,117 ) $ 27,883
Schedule of interest expense on debt	The following summarizes interest expense for the broker-dealer facilities. Interest expense is included within interest and dividends expense in the accompanying condensed consolidated statements of comprehensive income. Three Months Ended March 31, (in thousands) 2018 2017 Broker-dealer credit facilities: Uncommitted facility $ 446 $ 415 Committed facility (1) — 7 Revolving credit facility 98 — $ 544 $ 422 (1) Facility was terminated in July 2017.
Schedule of aggregate future required principal payments based on terms of loan	Aggregate future required minimum principal payments based on the terms of the long-term borrowings at March 31, 2018 were as follows: (in thousands) 2018 $ — 2019 — 2020 32,932 2021 and thereafter 1,124,000 Total principal of long-term borrowings $ 1,156,932
Short-Term Credit Facilities
Debt Instrument [Line Items]
Schedule of reconciliation of the senior secured credit facility	At March 31, 2018 Weighted Average Financing Borrowing Short-Term Credit Facilities: Short-term credit facilities (2) 4.04% $ 535,000 $ 131,382 $ 535,000 $ 131,382 At December 31, 2017 Weighted Average Interest Rate Financing Available Borrowing Outstanding Short-Term Credit Facilities: Short-term credit facilities (2) 3.86% $ 543,000 $ 205,677 $ 543,000 $ 205,677 (2) Outstanding borrowings were included with receivable from/ payable to broker-dealers and clearing organization within the condensed consolidated statements of financial condition.
Senior Secured Credit Facility
Debt Instrument [Line Items]
Schedule of reconciliation of the senior secured credit facility	The following summarizes the Company’s long-term borrowings, net of unamortized discount and debt issuance costs, where applicable: At March 31, 2018 (in thousands) Maturity Interest Outstanding Principal Discount Deferred Debt Issuance Cost Outstanding Borrowings, net Long-term borrowings: Fourth Amended and Restated Credit Agreement December 2021 4.94% $ 624,000 $ (650 ) $ (13,101 ) $ 610,249 Senior secured Second Lien Notes June 2022 6.75% 500,000 — (21,673 ) 478,327 SBI bonds January 2020 5.00% 32,932 — (44 ) 32,888 $ 1,156,932 $ (650 ) $ (34,818 ) $ 1,121,464 At December 31, 2017 (in thousands) Maturity Date Interest Rate Outstanding Principal Discount Deferred Debt Issuance Cost Outstanding Borrowings, net Long-term borrowings: Fourth Amended and Restate Credit Agreement December 2021 5.13% $ 900,000 $ (999 ) $ (18,504 ) $ 880,497 Senior secured Second Lien Notes June 2022 6.75% 500,000 — (22,961 ) 477,039 SBI bonds January 2020 5.00% 31,059 — (47 ) 31,012 $ 1,431,059 $ (999 ) $ (41,512 ) $ 1,388,548

Financial Assets and Liabilit37

Financial Assets and Liabilities (Tables)	3 Months Ended
	Mar. 31, 2018
Fair Value Disclosures [Abstract]
Summary of fair value measurements measured on a recurring basis	Fair value measurements for those items measured on a recurring basis are summarized below as of March 31, 2018 : March 31, 2018 (in thousands) Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Counterparty and Cash Collateral Netting Total Fair Value Assets Financial instruments owned, at fair value: Equity securities $ 956,518 $ 1,139,469 $ — $ — $ 2,095,987 U.S. and Non-U.S. government obligations 800 18,207 — — 19,007 Corporate Bonds — 75,534 — — 75,534 Exchange traded notes 64,730 30,368 — — 95,098 Currency forwards — 702,889 — (700,655 ) 2,234 Options 9,210 — — — 9,210 1,031,258 1,966,467 — (700,655 ) 2,297,070 Financial instruments owned, pledged as collateral: Equity securities $ 309,313 $ 262,684 $ — $ — $ 571,997 U.S. and Non-U.S. government obligations 200 — — — 200 Exchange traded notes 22,418 15,921 — — 38,339 331,931 278,605 — — 610,536 Other Assets Equity investment $ — $ — $ 42,478 $ — $ 42,478 Exchange stock 2,154 — — — 2,154 Other (1) — 56,179 — — 56,179 2,154 56,179 42,478 — 100,811 Liabilities Financial instruments sold, not yet purchased, at fair value: Equity securities $ 1,584,268 $ 1,132,360 $ — $ — $ 2,716,628 U.S. and Non-U.S. government obligations 1,998 25,207 — — 27,205 Corporate Bonds 40,007 — — — 40,007 Exchange traded notes 3,714 38,393 — — 42,107 Currency forwards — 725,422 — (720,464 ) 4,958 Options 15,548 — — — 15,548 $ 1,645,535 $ 1,921,382 $ — $ (720,464 ) $ 2,846,453 (1) Other primarily consists of a $56.2 million receivable from Bats related to the sale of KCG Hotspot. Fair value measurements for those items measured on a recurring basis are summarized below as of December 31, 2017 : December 31, 2017 (in thousands) Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Counterparty and Cash Collateral Netting Total Fair Value Assets Financial instruments owned, at fair value: Equity securities $ 758,596 $ 1,167,995 $ — $ — $ 1,926,591 Non-U.S. government obligations 5,968 16,815 — — 22,783 Corporate Bonds — 60,975 — — 60,975 Exchange traded notes 13,576 68,819 — — 82,395 Currency forwards — 2,045,487 — (2,027,697 ) 17,790 Options 7,045 — — — 7,045 $ 785,185 $ 3,360,091 $ — $ (2,027,697 ) $ 2,117,579 Financial instruments owned, pledged as collateral: Equity securities $ 410,670 $ 175,581 $ — $ — $ 586,251 U.S. and Non-U.S. government obligations 99 — — — 99 Exchange traded notes 82 8,611 — — 8,693 $ 410,851 $ 184,192 $ — $ — $ 595,043 Other Assets Equity investment $ — $ — $ 40,588 $ — $ 40,588 Exchange stock 1,952 — — — 1,952 Other (2) — 55,824 — — 55,824 $ 1,952 $ 55,824 $ 40,588 $ — $ 98,364 Liabilities Financial instruments sold, not yet purchased, at fair value: Equity securities $ 847,816 $ 1,355,616 $ — $ — $ 2,203,432 Exchange traded notes 1,514 54,248 — — 55,762 Currency forwards — 2,032,017 — (2,024,991 ) 7,026 Options 5,839 — — — 5,839 $ 874,109 $ 3,535,480 $ — $ (2,024,991 ) $ 2,384,598 (2) Other primarily consists of a $55.8 million receivable from Bats related to the sale of KCG Hotspot.
Summary of fair value measurements not measured on a recurring basis	The table below summarizes financial assets and liabilities not measured at fair value on a recurring basis as of March 31, 2018 : March 31, 2018 Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Carrying Value Fair Value (Level 1) (Level 2) (Level 3) Assets Cash and cash equivalents $ 637,308 $ 637,308 $ 637,308 $ — $ — Securities borrowed 1,232,048 1,232,048 — 1,232,048 — Securities purchased under agreements to resell 602 602 — 602 — Receivables from broker dealers and clearing organizations 1,434,039 1,434,039 70,143 1,363,896 — Total Assets $ 3,303,997 $ 3,303,997 $ 707,451 $ 2,596,546 $ — Liabilities Short-term borrowings $ 20,944 $ 20,944 $ — $ 20,944 $ — Long-term borrowings 1,121,464 1,193,167 — 1,193,167 — Securities loaned 936,061 936,061 — 936,061 — Securities sold under agreements to repurchase 265,401 265,401 — 265,401 — Payables to broker dealer and clearing organizations 648,788 648,788 861 647,927 — Total Liabilities $ 2,992,658 $ 3,064,361 $ 861 $ 3,063,500 $ — The table below summarizes financial assets and liabilities not measured at fair value on a recurring basis as of December 31, 2017 : December 31, 2017 Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Carrying Value Fair Value (Level 1) (Level 2) (Level 3) Assets Cash and cash equivalents $ 532,887 $ 532,887 $ 532,887 $ — $ — Securities borrowed 1,471,172 1,471,172 — 1,471,172 — Receivables from broker dealers and clearing organizations 972,018 972,018 36,513 935,505 — Total Assets $ 2,976,077 $ 2,976,077 $ 569,400 $ 2,406,677 $ — Liabilities Short-term borrowings $ 27,883 $ 27,883 $ — $ 27,883 $ — Long-term borrowings 1,388,548 1,465,489 — 1,465,489 — Securities loaned 754,687 754,687 — 754,687 — Securities sold under agreements to repurchase 390,642 390,642 — 390,642 — Payables to broker dealer and clearing organizations 716,205 716,205 2,925 713,280 — Total Liabilities $ 3,277,965 $ 3,354,906 $ 2,925 $ 3,351,981 $ —
Summary of changes in Level 3 financial instruments measured at fair value on a recurring basis	The following presents the changes in Level 3 financial instruments measured at fair value on a recurring basis: March 31, 2018 (in thousands) December 31, 2017 Purchases Total Realized and Unrealized Gains / (Losses) Net Transfers into (out of) Level 3 Settlement March 31, 2018 Change in Net Unrealized Gains / (Losses) on Investments still held at March 31, 2018 Assets Other assets: Equity investment $ 40,588 $ — $ 1,890 $ — $ — $ 42,478 $ 1,890 Total $ 40,588 $ — $ 1,890 $ — $ — $ 42,478 $ 1,890 December 31, 2017 (in thousands) December 31, 2016 Purchases Total Realized and Unrealized Gains / (Losses) Net Transfers into (out of) Level 3 Settlement December 31, 2017 Change in Net Unrealized Gains / (Losses) on Investments still held at December 31, 2017 Assets Other assets: Equity investment $ 36,031 $ — $ 4,557 $ — $ — $ 40,588 $ 4,557 Other — 3,000 — — (3,000 ) — — Total $ 36,031 $ 3,000 $ 4,557 $ — $ (3,000 ) $ 40,588 $ 4,557
Summary of netting of certain financial assets and financial liabilities	The following tables set forth the gross and net presentation of certain financial assets and financial liabilities as of March 31, 2018 and December 31, 2017 . March 31, 2018 Gross Amounts of Recognized Assets Gross Amounts Offset in the Condensed Consolidated Statement of Financial Condition Net Amounts of Assets Presented in the Condensed Consolidated Statement of Financial Condition Gross Amounts Not Offset In the Statement of Financial Condition (in thousands) Financial Instruments Cash Collateral Received Net Amount Offsetting of Financial Assets: Securities borrowed $ 1,232,048 $ — $ 1,232,048 $ (1,202,760 ) $ (2,624 ) $ 26,664 Securities purchased under agreements to resell 602 — 602 (602 ) — — Trading assets, at fair value: Currency forwards 702,889 (700,655 ) 2,234 — — 2,234 Options 9,210 — 9,210 (1 ) — 9,209 Total $ 1,944,749 $ (700,655 ) $ 1,244,094 $ (1,203,363 ) $ (2,624 ) $ 38,107 Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Consolidated Statement of Financial Condition Net Amounts of Assets Presented in the Consolidated Statement of Financial Condition Gross Amounts Not Offset In the Statement of Financial Condition (in thousands) Financial Instruments Cash Collateral Pledged Net Amount Offsetting of Financial Liabilities: Securities loaned $ 936,061 $ — $ 936,061 $ (929,457 ) $ (884 ) $ 5,720 Securities sold under agreements to repurchase 265,401 — 265,401 (265,401 ) — — Trading liabilities, at fair value: Currency forwards 725,422 (720,464 ) 4,958 — 4,958 Options 15,548 — 15,548 (1 ) — 15,547 Total $ 1,942,432 $ (720,464 ) $ 1,221,968 $ (1,194,859 ) $ (884 ) $ 26,225 December 31, 2017 Gross Amounts of Recognized Assets Gross Amounts Offset in the Consolidated Statement of Financial Condition Net Amounts of Assets Presented in the Consolidated Statement of Financial Condition Gross Amounts Not Offset In the Statement of Financial Condition (in thousands) Financial Instruments Cash Collateral Received Net Amount Offsetting of Financial Assets: Securities borrowed $ 1,471,172 $ — $ 1,471,172 $ (1,418,672 ) $ (13,318 ) $ 39,182 Trading assets, at fair value: Currency forwards 2,045,487 (2,027,697 ) 17,790 — — 17,790 Options 7,045 — 7,045 (45 ) — 7,000 Total $ 3,523,704 $ (2,027,697 ) $ 1,496,007 $ (1,418,717 ) $ (13,318 ) $ 63,972 Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Consolidated Statement of Financial Condition Net Amounts of Assets Presented in the Consolidated Statement of Financial Condition Gross Amounts Not Offset In the Statement of Financial Condition (in thousands) Financial Instruments Cash Collateral Pledged Net Amount Offsetting of Financial Liabilities: Securities loaned $ 754,687 $ — $ 754,687 $ (737,731 ) $ (10,776 ) $ 6,180 Securities sold under agreements to repurchase 390,642 — 390,642 (390,642 ) — — Trading liabilities, at fair value: Currency forwards 2,032,017 (2,024,991 ) 7,026 — 7,026 Options 5,839 — 5,839 (56 ) — 5,783 Total $ 3,183,185 $ (2,024,991 ) $ 1,158,194 $ (1,128,429 ) $ (10,776 ) $ 18,989
Summary of gross obligations for repurchase agreement and securities borrowed transactions by remaining contractual maturity and class of collateral pledged	The following table presents gross obligations for securities sold under agreements to repurchase and for securities lending transactions by remaining contractual maturity and the class of collateral pledged. March 31, 2018 Remaining Contractual Maturity (in thousands) Overnight and Continuous Less than 30 days 30 - 60 days 61 - 90 Days Total Repurchase agreements: Equity securities $ 401 $ — $ 65,000 $ 200,000 $ 265,401 U.S. and Non-U.S. government obligations — — — — Total $ 401 $ — $ 65,000 $ 200,000 $ 265,401 Securities lending transactions: Equity securities $ 936,061 $ — $ — $ — $ 936,061 Total $ 936,061 $ — $ — $ — $ 936,061 December 31, 2017 Remaining Contractual Maturity (in thousands) Overnight and Continuous Less than 30 days 30 - 60 days 61 - 90 Days Total Repurchase agreements: Equity securities $ — $ 100,000 $ 90,000 $ 200,000 $ 390,000 U.S. and Non-U.S. government obligations 642 — — — 642 Total $ 642 $ 100,000 $ 90,000 $ 200,000 $ 390,642 Securities lending transactions: Equity securities $ 754,687 $ — $ — $ — $ 754,687 Total $ 754,687 $ — $ — $ — $ 754,687

Derivative Instruments (Tables)

Derivative Instruments (Tables)	3 Months Ended
	Mar. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of fair value of derivative instruments on a gross basis	The fair value of the Company’s derivative instruments on a gross basis consisted of the following at March 31, 2018 and December 31, 2017 : (in thousands) March 31, 2018 December 31, 2017 Derivatives Assets Financial Statements Location Fair Value Notional Fair Value Notional Derivative instruments not designated as hedging instruments: Equities futures Receivables from broker dealers and clearing organizations $ 183 $ 4,836,630 $ (505 ) $ 1,985,770 Commodity futures Receivables from broker dealers and clearing organizations 39,965 20,971,297 971 21,231,001 Currency futures Receivables from broker dealers and clearing organizations 32,042 2,075,544 26,548 3,994,412 Fixed income futures Receivables from broker dealers and clearing organizations 23 10,096 73 44,395 Options Financial instruments owned 9,210 793,423 7,045 682,369 Currency forwards Financial instruments owned 702,889 100,689,302 2,045,487 124,000,221 Derivatives Liabilities Financial Statements Location Fair Value Notional Fair Value Notional Derivative instruments not designated as hedging instruments: Equities futures Payables to broker dealers and clearing organizations $ 208 $ 139,033 $ (575 ) $ 142,658 Commodity futures Payables to broker dealers and clearing organizations 645 118,427 (1,602 ) 130,042 Currency futures Payables to broker dealers and clearing organizations (3,279 ) 2,531,734 (13,947 ) 7,756,958 Fixed income futures Payables to broker dealers and clearing organizations (169 ) 13,016 (1 ) 2,584 Options Financial instruments sold, not yet purchased 15,548 769,273 5,839 681,147 Currency forwards Financial instruments sold, not yet purchased 725,058 100,700,387 2,032,017 123,993,234 Derivative instruments designated as hedging instruments: Currency forwards Financial instruments sold, not yet purchased (364 ) 15,964 (514 ) 16,115
Schedule of net gain from derivative instruments not designated as hedging instruments	The following table summarizes the net gain from derivative instruments not designated as hedging instruments under ASC 815, which are recorded in trading income, net, and from those designated as hedging instrument under ASC 815, which are recorded in accumulated other comprehensive income in the accompanying condensed consolidated statements of comprehensive income for the three months ended March 31, 2018 and 2017 . March 31, (in thousands) Financial Statements Location 2018 2017 Derivative instruments not designated as hedging instruments: Futures Trading income, net $ (436,414 ) $ 165,590 Currency forwards Trading income, net 85,910 (51,381 ) Options Trading income, net 1,102 1 $ (349,402 ) $ 114,210 Derivative instruments designated as hedging instruments: Foreign exchange - forward contract Accumulated other comprehensive income $ 150 $ —

Revenues from Contracts with 39

Revenues from Contracts with Customers (Tables)	3 Months Ended
	Mar. 31, 2018
Revenue Recognition [Abstract]
Disaggregation of Revenue	The following tables present the Company’s revenue from contracts with customers disaggregated by the services described above, by timing of revenue recognition, reconciled to the Company’s reportable segments, as well as disaggregation of the Company’s revenues by services and geographic region, for the three months ended March 31, 2018 : (in thousands) Market Making Execution Services Corporate Revenues from contract with Customers: Commissions, net 8,501 43,008 — Technology services — 2,335 — Total revenue from contract with customers 8,501 45,343 — Other sources of revenue 424,035 338,436 (1,262 ) Total Revenues 432,536 383,779 (1,262 ) Timing of revenue recognition: Services transferred at a point in time 432,536 381,444 (1,262 ) Services transferred over time — 2,335 — Total Revenues 432,536 383,779 (1,262 )

Share-based Compensation (Table

Share-based Compensation (Tables)	3 Months Ended
	Mar. 31, 2018
Non-qualified stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule of activity	The following table summarizes activity related to stock options for the three months ended March 31, 2018 and 2017 : Options Outstanding Options Exercisable Number of Options Weighted Average Exercise Price Per Share Weighted Average Remaining Contractual Life Number of Options Weighted Average Exercise Price Per Share December 31, 2016 8,234,000 $ 19.00 8.29 2,058,500 $ 19.00 Granted — — — — — Exercised — — — — — Forfeited or expired (195,000 ) — — — — March 31, 2017 8,039,000 $ 19.00 8.05 2,009,750 $ 19.00 December 31, 2017 7,783,000 $ 19.00 7.29 3,891,500 $ 19.00 Granted — — — — — Exercised (732,000 ) 19.00 — (732,000 ) 19.00 Forfeited or expired — — — — — March 31, 2018 7,051,000 $ 19.00 7.05 3,182,000 $ 19.00
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule of activity related to restricted stock units	The following table summarizes activity related to the RSUs: Number of Shares Weighted Average Fair Value At December 31, 2016 1,573,441 $ 18.28 Granted — — Forfeited (95,481 ) 18.38 Vested — — At March 31, 2017 1,477,960 $ 18.28 At December 31, 2017 853,047 $ 17.94 Granted 1,044,690 20.64 Forfeited (30,626 ) 18.52 Vested — — At March 31, 2018 1,867,111 $ 18.85

Regulatory Requirement (Tables)

Regulatory Requirement (Tables)	3 Months Ended
	Mar. 31, 2018
Regulatory Capital Requirements [Abstract]
Schedule of regulatory capital and regulatory capital requirements	The regulatory capital and regulatory capital requirements of these subsidiaries as of March 31, 2018 was as follows: (in thousands) Regulatory Capital Regulatory Capital Requirement Excess Regulatory Capital Virtu Americas LLC $ 411,168 $ 1,000 $ 410,168 Virtu Financial BD LLC 88,280 1,000 87,280 Virtu Financial Capital Markets LLC 8,563 4,696 3,867 The regulatory capital and regulatory capital requirements of these subsidiaries as of December 31, 2017 was as follows: (in thousands) Regulatory Capital Regulatory Capital Requirement Excess Regulatory Capital Virtu Americas LLC $ 379,875 $ 1,000 $ 378,875 Virtu Financial BD LLC 40,683 1,000 39,683 Virtu Financial Capital Markets LLC 8,308 5,114 3,194

Geographic Information and Bu42

Geographic Information and Business Segments (Tables)	3 Months Ended
	Mar. 31, 2018
Segment Reporting [Abstract]
Schedule of total revenues by geographic area	The following table presents total revenues by geographic area for the three months ended March 31, 2018 and 2017 : (in thousands) 2018 2017 Revenues: United States $ 743,152 $ 91,987 Ireland 14,023 28,251 United Kingdom 11,600 — Singapore 46,200 27,006 Others 78 43 Total revenues 815,053 147,287
Schedule of revenues, income (loss) before income taxes (“Pre-tax earnings”) and total assets by segment	The Company’s total revenues and income before income taxes and noncontrolling interest (“Pre-tax earnings”) by segment for the three months ended March 31, 2018 and 2017 are summarized in the following table: (in thousands) Market Making Execution Services Corporate (1) Consolidated Total 2018: Total revenue $ 432,536 $ 383,779 $ (1,262 ) $ 815,053 Income before income taxes and noncontrolling interest 163,163 331,185 (25,812 ) 468,536 2017: Total revenue $ 144,448 $ 2,779 $ 60 $ 147,287 Income (loss) before income taxes and noncontrolling interest 23,465 489 (72 ) 23,882 (1) Amounts shown in the Corporate segment include eliminations of income statement and balance sheet items included in the Company's other segments.

Organization and Basis of Pre43

Organization and Basis of Presentation (Details) $ in Thousands	Jan. 02, 2018USD ($)	Jul. 19, 2017businesssegment	Mar. 31, 2018USD ($)	Sep. 30, 2017segment	Mar. 31, 2017USD ($)
Organization, Consolidation And Presentation Of Financial Statements [Line Items]
Proceeds from sale of business | $			$ 400,192		$ 0
Number of businesses Company is managed and operated as | business		1
Number of reportable segments | segment		1
Number of operating segments | segment				3
Disposal Group, Disposed of by Sale, Not Discontinued Operations | BondPoint
Organization, Consolidation And Presentation Of Financial Statements [Line Items]
Proceeds from sale of business | $	$ 400,192
Virtu Financial
Organization, Consolidation And Presentation Of Financial Statements [Line Items]
Ownership interest (as a percent)			49.10%

Summary of Significant Accoun44

Summary of Significant Accounting Policies (Details)	3 Months Ended
	Mar. 31, 2018
Securities Borrowed and Securities Loaned
Minimum initial collateral advanced or received expressed as a percentage of fair value of the underlying securities borrowed or loaned	102.00%
Furniture, fixtures and equipment | Minimum
Securities Borrowed and Securities Loaned
Estimated useful lives	3 years
Furniture, fixtures and equipment | Maximum
Securities Borrowed and Securities Loaned
Estimated useful lives	7 years
Capitalized software | Minimum
Securities Borrowed and Securities Loaned
Estimated useful lives	1 year 6 months
Capitalized software | Maximum
Securities Borrowed and Securities Loaned
Estimated useful lives	2 years 6 months

Summary of Significant Accoun45

Summary of Significant Accounting Policies - Goodwill, Income Taxes and VIE (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)party	Dec. 31, 2017USD ($)
Share-Based Compensation
Number of days prior to the grant that common stock and restricted stock units fair value is determined based on	3 days
Variable Interest Entity
Carrying amount asset	$ 18,472	$ 18,799
Maximum exposure to loss	18,472	18,799
VIE's assets	$ 51,344	$ 41,936
JV building microwave communication networks in US and Asia
Variable Interest Entity
Number of other investors in JV | party	9
Ownership of voting shares of JV held be each investor (as a percent)	11.00%
Ownership of equity of JV held be each investor (as a percent)	11.00%
JV building microwave communication networks in US and Europe
Variable Interest Entity
Ownership of voting shares (as a percent)	50.00%
Ownership interest (as a percent)	50.00%

Acquisition of KCG Holdings, 46

Acquisition of KCG Holdings, Inc. (Details) - USD ($) $ / shares in Units, $ in Millions	Aug. 10, 2017	Jul. 21, 2017	Jul. 20, 2017	Mar. 31, 2018	Dec. 31, 2017
Temasek Investment
Business Acquisition [Line Items]
Other offering costs	$ 7.8
Senior Secured Notes Due 2020
Business Acquisition [Line Items]
Interest rate (as a percent)		6.875%
Redemption price as a percentage of the principal amount		103.438%
Face amount		$ 465
Class A
Business Acquisition [Line Items]
Common stock, par value (in dollars per share)				$ 0.00001	$ 0.00001
Class A | NIH Investment Agreement
Business Acquisition [Line Items]
Number of shares of stock issued	338,124
Aggregate purchase price	$ 5.2
KCG
Business Acquisition [Line Items]
Common stock, par value (in dollars per share)			$ 0.01
Right to receive cash (in dollars per share)			$ 20
Cash purchase price			$ 1,400
Fair value ( in dollars per share)			$ 20
KCG | NIH Investment Agreement
Business Acquisition [Line Items]
Number of shares of stock issued			39,725,979
Aggregate purchase price			$ 613.5
KCG | Class A | Aranda
Business Acquisition [Line Items]
Number of shares of stock issued			6,346,155
Aggregate purchase price			$ 99
KCG | Class A | Temasek Investment
Business Acquisition [Line Items]
Number of shares of stock issued	1,666,666
Aggregate purchase price	$ 26
KCG | Class A | NIH Investment Agreement
Business Acquisition [Line Items]
Number of shares of stock issued	338,124
Aggregate purchase price	$ 5.2

Acquisition of KCG Holdings, 47

Acquisition of KCG Holdings, Inc. - Intangible assets (Details) - USD ($)	Jul. 20, 2017	Mar. 31, 2018	Dec. 31, 2017
Amounts preliminarily allocated to intangible assets, the amortization period and goodwill
Intangible assets		$ 104,387,000	$ 111,224,000
Goodwill		836,583,000	844,883,000
Deferred tax assets		123,289,000	125,760,000
Customer relationships
Amounts preliminarily allocated to intangible assets, the amortization period and goodwill
Intangible assets		46,157,000	47,178,000
Favorable leases
Amounts preliminarily allocated to intangible assets, the amortization period and goodwill
Intangible assets		5,283,000	5,487,000
KCG
Amounts preliminarily allocated to intangible assets, the amortization period and goodwill
Intangible assets	$ 174,995,000
Goodwill	128,286,000
Total	303,281,000
Goodwill deductible for tax purposes	0
Deferred tax assets	23,900,000
KCG | Technology
Amounts preliminarily allocated to intangible assets, the amortization period and goodwill
Intangible assets	67,700,000
KCG | Customer relationships
Amounts preliminarily allocated to intangible assets, the amortization period and goodwill
Intangible assets	94,000,000
KCG | Trade names
Amounts preliminarily allocated to intangible assets, the amortization period and goodwill
Intangible assets	$ 1,000,000
Amortization Years	10 years
KCG | Favorable leases
Amounts preliminarily allocated to intangible assets, the amortization period and goodwill
Intangible assets	$ 5,895,000
KCG | Exchange memberships
Amounts preliminarily allocated to intangible assets, the amortization period and goodwill
Intangible assets	$ 6,400,000
Minimum | KCG | Technology
Amounts preliminarily allocated to intangible assets, the amortization period and goodwill
Amortization Years	1 year
Minimum | KCG | Customer relationships
Amounts preliminarily allocated to intangible assets, the amortization period and goodwill
Amortization Years	13 years
Minimum | KCG | Favorable leases
Amounts preliminarily allocated to intangible assets, the amortization period and goodwill
Amortization Years	2 years
Maximum | KCG | Technology
Amounts preliminarily allocated to intangible assets, the amortization period and goodwill
Amortization Years	6 years
Maximum | KCG | Customer relationships
Amounts preliminarily allocated to intangible assets, the amortization period and goodwill
Amortization Years	17 years
Maximum | KCG | Favorable leases
Amounts preliminarily allocated to intangible assets, the amortization period and goodwill
Amortization Years	15 years
Market Making
Amounts preliminarily allocated to intangible assets, the amortization period and goodwill
Goodwill	$ 96,200,000	$ 755,292,000	$ 755,292,000
Technology and Execution Services
Amounts preliminarily allocated to intangible assets, the amortization period and goodwill
Goodwill	$ 32,100,000

Sale of BondPoint (Details)

Sale of BondPoint (Details) - USD ($) $ in Thousands	Jan. 02, 2018	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of BondPoint		$ 400,192	$ 0
Assets and liabilities of businesses held for sale
Goodwill adjustment allocated to BondPoint		8,300
Gain on sale of BondPoint, net of transaction costs		$ 329,703	$ 0
BondPoint | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of BondPoint	$ 400,192
Professional fees	7,100
Compensation	1,400
Assets and liabilities of businesses held for sale
Goodwill adjustment allocated to BondPoint	8,300
Gain on sale of BondPoint	337,550
Transaction costs	8,568
Gain on sale of BondPoint, net of transaction costs	$ 328,982
BondPoint | Held for Sale
Assets and liabilities of businesses held for sale
Receivables from broker dealers and clearing organizations				$ 3,383
Intangibles and other assets				51,687
Liabilities				(728)
Total carrying value of BondPoint as of December 31, 2017:				$ 54,342

Earnings Per Share - Reconcilia

Earnings Per Share - Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Reconciliation of net income before minority interest to net income available for common stockholders
Income before income taxes and non-controlling interest	$ 468,536	$ 23,882
Provision for income taxes	58,514	2,808
Net income	410,022	21,074
Noncontrolling interest	(235,271)	(16,494)
Net income available for common stockholders	$ 174,751	$ 4,580

Earnings Per Share - Basic (Det

Earnings Per Share - Basic (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Basic earnings per share
Net income available for common stockholders	$ 174,751	$ 4,580
Less: Dividends and undistributed earnings allocated to participating securities	(3,213)	(353)
Net income available for common stockholders, net of dividends and undistributed earnings allocated to participating securities	$ 171,538	$ 4,227
Weighted average shares of common stock outstanding
Outstanding (in shares)	90,699,321	40,398,381
Basic Earnings per share (in dollars per share)	$ 1.89	$ 0.10
Class A
Weighted average shares of common stock outstanding
Outstanding (in shares)	90,699,321	40,398,381

Earnings Per Share - Diluted (D

Earnings Per Share - Diluted (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Diluted earnings per share
Net income available for common stockholders, net of dividends and undistributed earnings allocated to participating securities	$ 171,538	$ 4,227
Weighted average shares of common stock outstanding
Issued and outstanding (in shares)	90,699,321	40,398,381
Weighted average shares of common stock outstanding (in shares)	92,406,318	40,398,381
Diluted Earnings per share (in dollars per share)	$ 1.86	$ 0.10
Anti-dilutive shares excluded from computation of EPS		774,529
Class A
Weighted average shares of common stock outstanding
Issued and outstanding (in shares)	90,699,321	40,398,381
Issuable pursuant to 2015 Management Incentive Plan (in shares)	1,706,996	0
Weighted average shares of common stock outstanding (in shares)	92,406,317	40,398,381

Tax Receivable Agreements (Deta

Tax Receivable Agreements (Details) - USD ($) $ in Thousands	Jan. 01, 2018	Apr. 15, 2015	Feb. 28, 2017	Mar. 31, 2018	Dec. 31, 2017
Tax Receivable Agreements [Abstract]
Payment on applicable cash tax savings (as a percent)		85.00%
First payment made			$ 7,000
Deferred tax assets related to exchange of units		$ 220,800
Minimum tax receivable agreement obligation over the agreed period		300
Maximum tax receivable agreement obligation over the agreed period		$ 12,800
Period over which the obligations are to be settled		15 years
Reduction of paid-in capital for the difference between TRA liability and related deferred tax asset.		$ 19,900
U.S. federal statutory rate (as a percent)	21.00%				35.00%
Reduction to additional paid-in capital as a result of differences between estimate and tax returns				$ 86,600
Deferred tax assets				99,100	$ 101,600
Tax receivable agreement obligations				$ 147,040	$ 147,040

Goodwill and Intangible Asset53

Goodwill and Intangible Assets - Goodwill (Details)	Jan. 02, 2018USD ($)	Jul. 19, 2017businesssegment	Mar. 31, 2018USD ($)	Sep. 30, 2017segment	Mar. 31, 2017USD ($)	Jul. 20, 2017USD ($)
Goodwill
Number of businesses Company is managed and operated as | business		1
Number of reportable segments | segment		1
Number of operating segments | segment				3
Changes in goodwill
Balance at the beginning of the period			$ 844,883,000
Goodwill adjustment allocated to BondPoint			(8,300,000)
Balance at the end of the period			836,583,000
Goodwill			844,883,000
Goodwill impairment			0		$ 0
Market Making
Changes in goodwill
Balance at the beginning of the period			755,292,000
Goodwill adjustment allocated to BondPoint			0
Balance at the end of the period			755,292,000
Goodwill			755,292,000			$ 96,200,000
Execution Services
Changes in goodwill
Balance at the beginning of the period			89,591,000
Goodwill adjustment allocated to BondPoint			(8,300,000)
Balance at the end of the period			81,291,000
Goodwill			89,591,000
Corporate
Changes in goodwill
Balance at the beginning of the period			0
Goodwill adjustment allocated to BondPoint			0
Balance at the end of the period			0
Goodwill			$ 0
BondPoint | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Changes in goodwill
Goodwill adjustment allocated to BondPoint	$ (8,300,000)

Goodwill and Intangible Asset54

Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Acquired intangible assets
Accumulated Amortization	$ 130,246		$ 123,409
Net Carrying Amount	104,387		111,224
Gross Carrying Amount	234,633		234,633
Net Carrying Amount	104,387		111,224
Amortization expense relating to finite-lived intangible assets	6,851	$ 53
Exchange memberships
Acquired intangible assets
Indefinite-lived intangibles	5,838		5,838
Purchased technology
Acquired intangible assets
Gross Carrying Amount	110,000		110,000
Accumulated Amortization	110,000		110,000
Net Carrying Amount	$ 0		$ 0
Purchased technology | Minimum
Acquired intangible assets
Useful Lives	1 year 4 months 24 days		1 year 4 months 24 days
Purchased technology | Maximum
Acquired intangible assets
Useful Lives	2 years 6 months		2 years 6 months
ETF issuer relationships
Acquired intangible assets
Gross Carrying Amount	$ 950		$ 950
Accumulated Amortization	585		559
Net Carrying Amount	$ 365		$ 391
Useful Lives	9 years		9 years
ETF buyer relationships
Acquired intangible assets
Gross Carrying Amount	$ 950		$ 950
Accumulated Amortization	586		560
Net Carrying Amount	$ 364		$ 390
Useful Lives	9 years		9 years
Leases
Acquired intangible assets
Gross Carrying Amount	$ 1,800		$ 1,800
Accumulated Amortization	547		397
Net Carrying Amount	$ 1,253		$ 1,403
Useful Lives	3 years		3 years
FCC licenses
Acquired intangible assets
Gross Carrying Amount	$ 200		$ 200
Accumulated Amortization	26		19
Net Carrying Amount	$ 174		$ 181
Useful Lives	7 years		7 years
Technology
Acquired intangible assets
Gross Carrying Amount	$ 60,000		$ 60,000
Accumulated Amortization	15,047		9,644
Net Carrying Amount	$ 44,953		$ 50,356
Technology | Minimum
Acquired intangible assets
Useful Lives	1 year		1 year
Technology | Maximum
Acquired intangible assets
Useful Lives	6 years		6 years
Customer relationships
Acquired intangible assets
Gross Carrying Amount	$ 49,000		$ 49,000
Accumulated Amortization	2,843		1,822
Net Carrying Amount	$ 46,157		$ 47,178
Customer relationships | Minimum
Acquired intangible assets
Useful Lives	12 years		12 years
Customer relationships | Maximum
Acquired intangible assets
Useful Lives	17 years		17 years
Favorable leases
Acquired intangible assets
Gross Carrying Amount	$ 5,895		$ 5,895
Accumulated Amortization	612		408
Net Carrying Amount	$ 5,283		$ 5,487
Useful Lives	7 years		7 years

Receivables from_Payables to 55

Receivables from/Payables to Broker-Dealers and Clearing Organizations (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Assets
Due from prime brokers	$ 153,716	$ 219,573
Deposits with clearing organizations	257,832	112,847
Net equity with futures commission merchants	308,964	203,711
Unsettled trades with clearing organization	430,514	173,778
Securities failed to deliver	271,287	248,088
Commissions and fees	11,726	14,021
Total receivables from broker-dealers and clearing organizations	1,434,039	972,018
Liabilities
Due to prime brokers	390,364	197,439
Net equity with futures commission merchants	40,665	44,526
Unsettled trades with clearing organization	150,205	420,029
Securities failed to receive	65,715	51,143
Commissions and fees	1,839	3,068
Total payables to broker-dealers and clearing organizations	648,788	716,205
Outstanding principal balance	$ 131,400	$ 205,700

Collateralized Transactions (De

Collateralized Transactions (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Securities received as collateral:
Securities borrowed	$ 1,201,721	$ 1,415,793
Total amounts related to collateralized transactions	1,201,721	1,415,793
Financial instruments owned and pledged
Financial instruments owned and pledged	610,536	595,043
Equities
Financial instruments owned and pledged
Financial instruments owned and pledged	571,997	586,251
U.S. and Non-U.S. government obligations
Financial instruments owned and pledged
Financial instruments owned and pledged	200	99
Exchange traded notes
Financial instruments owned and pledged
Financial instruments owned and pledged	$ 38,339	$ 8,693

Borrowings - Broker-Dealer Cred

Borrowings - Broker-Dealer Credit Facilities (Details)	Nov. 03, 2017USD ($)borrowing_basebroker_dealer	Mar. 31, 2018USD ($)broker_dealersubsidiary	Mar. 31, 2017USD ($)	Dec. 31, 2017USD ($)	Nov. 02, 2017USD ($)
Long-Term Borrowings
Number of borrowing bases | borrowing_base	2
Number of broker-dealer subsidiaries	3	3
Borrowing Outstanding		$ 1,156,932,000
Outstanding Borrowings, net		1,121,464,000		$ 1,388,548,000
Interest expense		$ 19,047,000	$ 6,828,000
LIBOR rate
Long-Term Borrowings
Interest rate margin (as a percent)	1.25%
Broker-Dealer Credit Facilities
Long-Term Borrowings
Number of secured credit facilities | broker_dealer		2
Financing Available	$ 500,000,000	$ 850,000,000		650,000,000	$ 25,000,000
Maximum borrowing capacity	$ 100,000,000				$ 40,000,000
Number of broker-dealer subsidiaries the committed facility is available to | broker_dealer	2
Commitment fee (as a percent)	0.50%
Borrowing Outstanding		24,500,000		32,000,000
Deferred Debt Issuance Cost		(3,556,000)		(4,117,000)
Outstanding Borrowings, net		20,944,000		27,883,000
Interest expense		$ 544,000	422,000
Broker-Dealer Credit Facilities | LIBOR rate
Long-Term Borrowings
Interest rate margin (as a percent)	2.50%
Broker-Dealer Credit Facility on an uncommitted basis
Long-Term Borrowings
Number of secured credit facilities | broker_dealer		1
Financing Available		$ 350,000,000		$ 150,000,000
Interest rate (as a percent)		2.68%		2.42%
Borrowing Outstanding		$ 17,500,000		$ 25,000,000
Deferred Debt Issuance Cost		(1,580,000)		0
Outstanding Borrowings, net		15,920,000		25,000,000
Interest expense		446,000	415,000
Broker-Dealer Credit Facility on committed basis
Long-Term Borrowings
Interest expense		0	7,000
Revolving credit facility
Long-Term Borrowings
Financing Available		$ 500,000,000		$ 500,000,000
Interest rate (as a percent)		3.13%		2.81%
Borrowing Outstanding		$ 7,000,000		$ 7,000,000
Deferred Debt Issuance Cost		(1,976,000)		(4,117,000)
Outstanding Borrowings, net		5,024,000		$ 2,883,000
Interest expense		$ 98,000	$ 0

Borrowings - Short-Term Credit

Borrowings - Short-Term Credit Facilities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Short-Term Credit Facilities
Borrowing Outstanding	$ 1,156,932
Interest expense	$ 19,047	$ 6,828
Short-Term Credit Facilities
Short-Term Credit Facilities
Weighted average interest rate	4.04%		3.86%
Financing Available	$ 535,000		$ 543,000
Borrowing Outstanding	131,382		$ 205,677
Interest expense	$ 1,500	$ 1,700

Borrowings - Long-Term Borrowin

Borrowings - Long-Term Borrowings (Details)	Nov. 03, 2017	Jan. 31, 2018	Mar. 31, 2018USD ($)	Mar. 31, 2017USD ($)	Mar. 31, 2018USD ($)	Mar. 31, 2018JPY (¥)	Dec. 31, 2017USD ($)	Dec. 31, 2017JPY (¥)	Jun. 30, 2017USD ($)	Jun. 16, 2017USD ($)	Jul. 25, 2016USD ($)	Jul. 25, 2016JPY (¥)
Reconciliation of senior secured credit facility
Outstanding Principal			$ 1,156,932,000		$ 1,156,932,000
Outstanding Borrowings, net			1,121,464,000		1,121,464,000		$ 1,388,548,000
Outstanding principal amount			1,156,932,000		1,156,932,000
Repayments of long-term debt			276,000,000	$ 1,350,000
Aggregate future required minimum principal payments based on the terms of loan
2,018			0		0
2,019			0		0
2,020			32,932,000		32,932,000
2021 and thereafter			1,124,000,000		1,124,000,000
Total principal of long-term borrowings			1,156,932,000		1,156,932,000
LIBOR rate
Reconciliation of senior secured credit facility
Interest rate added to variable rate (as a percent)	1.25%
Revolving credit facility
Reconciliation of senior secured credit facility
Outstanding Principal			7,000,000		7,000,000		7,000,000
Deferred Debt Issuance Cost			(1,976,000)		(1,976,000)		(4,117,000)
Outstanding Borrowings, net			5,024,000		5,024,000		2,883,000
Outstanding principal amount			7,000,000		7,000,000		7,000,000
Deferred Debt Issuance Cost			(1,976,000)		(1,976,000)		(4,117,000)
Aggregate future required minimum principal payments based on the terms of loan
Total principal of long-term borrowings			$ 7,000,000		$ 7,000,000		$ 7,000,000
Senior Secured Second Lien Notes
Reconciliation of senior secured credit facility
Interest rate (as a percent)										6.75%
Interest rate (as a percent)										6.75%
Face amount										$ 500,000,000
Senior Secured Credit Facility
Reconciliation of senior secured credit facility
Interest rate (as a percent)			4.94%		4.94%	4.94%	5.13%	5.13%
Outstanding Principal			$ 624,000,000		$ 624,000,000		$ 900,000,000
Discount			(650,000)		(650,000)		(999,000)
Deferred Debt Issuance Cost			(13,101,000)		(13,101,000)		(18,504,000)
Outstanding Borrowings, net			610,249,000		610,249,000		880,497,000
Outstanding principal amount			$ 624,000,000		$ 624,000,000		$ 900,000,000
Interest rate (as a percent)			4.94%		4.94%	4.94%	5.13%	5.13%
Deferred Debt Issuance Cost			$ (13,101,000)		$ (13,101,000)		$ (18,504,000)
Aggregate future required minimum principal payments based on the terms of loan
Total principal of long-term borrowings			$ 624,000,000		$ 624,000,000		$ 900,000,000
Senior Secured Credit Facility | Senior Secured Second Lien Notes
Reconciliation of senior secured credit facility
Interest rate (as a percent)			6.75%		6.75%	6.75%	6.75%	6.75%
Outstanding Principal			$ 500,000,000		$ 500,000,000		$ 500,000,000
Discount			0		0		0
Deferred Debt Issuance Cost			(21,673,000)		(21,673,000)		(22,961,000)
Outstanding Borrowings, net			478,327,000		478,327,000		477,039,000
Outstanding principal amount			$ 500,000,000		$ 500,000,000		$ 500,000,000
Interest rate (as a percent)			6.75%		6.75%	6.75%	6.75%	6.75%
Deferred Debt Issuance Cost			$ (21,673,000)		$ (21,673,000)		$ (22,961,000)
Aggregate future required minimum principal payments based on the terms of loan
Total principal of long-term borrowings			500,000,000		500,000,000		$ 500,000,000
Senior Secured Credit Facility Fourth Amendment
Reconciliation of senior secured credit facility
Outstanding Principal									$ 1,150,000,000
Outstanding principal amount									1,150,000,000
Repayments of long-term debt			276,000,000		$ 526,000,000
Accelerated unamortized financing costs			$ 6,000,000
Aggregate future required minimum principal payments based on the terms of loan
Total principal of long-term borrowings									$ 1,150,000,000
Senior Secured Credit Facility Fourth Amendment | LIBOR rate
Reconciliation of senior secured credit facility
Interest rate added to variable rate (as a percent)		3.25%
SBI Bonds
Reconciliation of senior secured credit facility
Interest rate (as a percent)			5.00%		5.00%	5.00%	5.00%	5.00%
Outstanding Principal			$ 32,932,000		$ 32,932,000		$ 31,059,000
Discount			0		0		0
Deferred Debt Issuance Cost			(44,000)		(44,000)		(47,000)
Outstanding Borrowings, net			32,888,000		32,888,000		31,012,000
Outstanding principal amount			$ 32,932,000		$ 32,932,000		$ 31,059,000
Interest rate (as a percent)			5.00%		5.00%	5.00%	5.00%	5.00%
Deferred Debt Issuance Cost			$ (44,000)		$ (44,000)		$ (47,000)
Aggregate future required minimum principal payments based on the terms of loan
Total principal of long-term borrowings			32,932,000		32,932,000		31,059,000
Total Long-term borrowings
Reconciliation of senior secured credit facility
Outstanding Principal			1,156,932,000		1,156,932,000		1,431,059,000
Discount			(650,000)		(650,000)		(999,000)
Deferred Debt Issuance Cost			(34,818,000)		(34,818,000)		(41,512,000)
Outstanding Borrowings, net			1,121,464,000		1,121,464,000		1,388,548,000
Outstanding principal amount			1,156,932,000		1,156,932,000		1,431,059,000
Deferred Debt Issuance Cost			(34,818,000)		(34,818,000)		(41,512,000)
Aggregate future required minimum principal payments based on the terms of loan
Total principal of long-term borrowings			1,156,932,000		1,156,932,000		1,431,059,000
VFH | SBI Bonds
Reconciliation of senior secured credit facility
Outstanding Principal			32,900,000		32,900,000	¥ 3,500,000,000	31,000,000	¥ 3,500,000,000
Outstanding principal amount			32,900,000		32,900,000	3,500,000,000	31,000,000	3,500,000,000
Face amount											$ 33,100,000	¥ 3,500,000,000
Loss due to change in currency rates			1,900,000	$ 1,500,000
Aggregate future required minimum principal payments based on the terms of loan
Total principal of long-term borrowings			$ 32,900,000		$ 32,900,000	¥ 3,500,000,000	$ 31,000,000	¥ 3,500,000,000

Financial Assets and Liabilit60

Financial Assets and Liabilities - Measured on a recurring basis (Details)	3 Months Ended	12 Months Ended
	Mar. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Mar. 31, 2017USD ($)
Fair value measurements measured on a recurring basis
Transfers of financial assets between levels	$ 0		$ 0
Assets
Financial instruments owned, at fair value	2,297,070,000	$ 2,117,579,000
Financial instruments owned and pledged	610,536,000	595,043,000
Other assets	100,811,000	98,364,000
Liabilities
Financial instruments sold, not yet purchased	2,846,453,000	2,384,598,000
Payment receivable	50,000,000
Remaining additional potential payments	56,600,000
Fair value of remaining additional potential payments	56,200,000
Equities
Assets
Financial instruments owned and pledged	571,997,000	586,251,000
U.S. and Non-U.S. government obligations
Assets
Financial instruments owned and pledged	200,000	99,000
Exchange traded notes
Assets
Financial instruments owned and pledged	38,339,000	8,693,000
Fair value measurements measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Financial instruments owned, at fair value	1,031,258,000	785,185,000
Financial instruments owned and pledged	331,931,000	410,851,000
Other assets	2,154,000	1,952,000
Liabilities
Financial instruments sold, not yet purchased	1,645,535,000	874,109,000
Fair value measurements measured on a recurring basis | Significant Other Observable Inputs (Level 2)
Assets
Financial instruments owned, at fair value	1,966,467,000	3,360,091,000
Financial instruments owned, at fair value, counterparty and cash collateral netting	(700,655,000)	(2,027,697,000)
Financial instruments owned and pledged	278,605,000	184,192,000
Other assets	56,179,000	55,824,000
Liabilities
Financial instruments sold, not yet purchased	1,921,382,000	3,535,480,000
Financial instruments sold, not yet purchased, at fair value, counterparty and cash collateral netting	(720,464,000)	(2,024,991,000)
Fair value measurements measured on a recurring basis | Significant Unobservable Inputs (Level 3)
Assets
Financial instruments owned, at fair value	0	0
Financial instruments owned and pledged	0	0
Other assets	42,478,000	40,588,000
Liabilities
Financial instruments sold, not yet purchased	0	0
Fair value measurements measured on a recurring basis | Currency forwards | Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Financial instruments owned, at fair value	0	0
Liabilities
Financial instruments sold, not yet purchased	0	0
Fair value measurements measured on a recurring basis | Currency forwards | Significant Other Observable Inputs (Level 2)
Assets
Financial instruments owned, at fair value	702,889,000	2,045,487,000
Financial instruments owned, at fair value, counterparty and cash collateral netting	(700,655,000)	(2,027,697,000)
Liabilities
Financial instruments sold, not yet purchased	725,422,000	2,032,017,000
Financial instruments sold, not yet purchased, at fair value, counterparty and cash collateral netting	(720,464,000)	(2,024,991,000)
Fair value measurements measured on a recurring basis | Currency forwards | Significant Unobservable Inputs (Level 3)
Assets
Financial instruments owned, at fair value	0	0
Liabilities
Financial instruments sold, not yet purchased	0	0
Fair value measurements measured on a recurring basis | Options | Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Financial instruments owned, at fair value	9,210,000	7,045,000
Liabilities
Financial instruments sold, not yet purchased	15,548,000	5,839,000
Fair value measurements measured on a recurring basis | Options | Significant Other Observable Inputs (Level 2)
Assets
Financial instruments owned, at fair value	0	0
Liabilities
Financial instruments sold, not yet purchased	0	0
Fair value measurements measured on a recurring basis | Options | Significant Unobservable Inputs (Level 3)
Assets
Financial instruments owned, at fair value	0	0
Liabilities
Financial instruments sold, not yet purchased	0	0
Fair value measurements measured on a recurring basis | Equities | Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Financial instruments owned, at fair value	956,518,000	758,596,000
Financial instruments owned and pledged	309,313,000	410,670,000
Liabilities
Financial instruments sold, not yet purchased	1,584,268,000	847,816,000
Fair value measurements measured on a recurring basis | Equities | Significant Other Observable Inputs (Level 2)
Assets
Financial instruments owned, at fair value	1,139,469,000	1,167,995,000
Financial instruments owned and pledged	262,684,000	175,581,000
Liabilities
Financial instruments sold, not yet purchased	1,132,360,000	1,355,616,000
Fair value measurements measured on a recurring basis | Equities | Significant Unobservable Inputs (Level 3)
Assets
Financial instruments owned, at fair value	0	0
Financial instruments owned and pledged	0	0
Liabilities
Financial instruments sold, not yet purchased	0	0
Fair value measurements measured on a recurring basis | U.S. and Non-U.S. government obligations | Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Financial instruments owned, at fair value	800,000	5,968,000
Financial instruments owned and pledged	200,000	99,000
Liabilities
Financial instruments sold, not yet purchased	1,998,000
Fair value measurements measured on a recurring basis | U.S. and Non-U.S. government obligations | Significant Other Observable Inputs (Level 2)
Assets
Financial instruments owned, at fair value	18,207,000	16,815,000
Financial instruments owned and pledged	0	0
Liabilities
Financial instruments sold, not yet purchased	25,207,000
Fair value measurements measured on a recurring basis | U.S. and Non-U.S. government obligations | Significant Unobservable Inputs (Level 3)
Assets
Financial instruments owned, at fair value	0	0
Financial instruments owned and pledged	0	0
Liabilities
Financial instruments sold, not yet purchased	0
Fair value measurements measured on a recurring basis | Corporate Bonds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Financial instruments owned, at fair value	0	0
Liabilities
Financial instruments sold, not yet purchased	40,007,000
Fair value measurements measured on a recurring basis | Corporate Bonds | Significant Other Observable Inputs (Level 2)
Assets
Financial instruments owned, at fair value	75,534,000	60,975,000
Liabilities
Financial instruments sold, not yet purchased	0
Fair value measurements measured on a recurring basis | Corporate Bonds | Significant Unobservable Inputs (Level 3)
Assets
Financial instruments owned, at fair value	0	0
Liabilities
Financial instruments sold, not yet purchased	0
Fair value measurements measured on a recurring basis | Exchange traded notes | Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Financial instruments owned, at fair value	64,730,000	13,576,000
Financial instruments owned and pledged	22,418,000	82,000
Liabilities
Financial instruments sold, not yet purchased	3,714,000	1,514,000
Fair value measurements measured on a recurring basis | Exchange traded notes | Significant Other Observable Inputs (Level 2)
Assets
Financial instruments owned, at fair value	30,368,000	68,819,000
Financial instruments owned and pledged	15,921,000	8,611,000
Liabilities
Financial instruments sold, not yet purchased	38,393,000	54,248,000
Fair value measurements measured on a recurring basis | Exchange traded notes | Significant Unobservable Inputs (Level 3)
Assets
Financial instruments owned, at fair value	0	0
Financial instruments owned and pledged	0	0
Liabilities
Financial instruments sold, not yet purchased	0	0
Fair value measurements measured on a recurring basis | Equity investment | Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Other assets	0	0
Fair value measurements measured on a recurring basis | Equity investment | Significant Other Observable Inputs (Level 2)
Assets
Other assets	0	0
Fair value measurements measured on a recurring basis | Equity investment | Significant Unobservable Inputs (Level 3)
Assets
Other assets	42,478,000	40,588,000
Fair value measurements measured on a recurring basis | Exchange stock | Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Other assets	2,154,000	1,952,000
Fair value measurements measured on a recurring basis | Exchange stock | Significant Other Observable Inputs (Level 2)
Assets
Other assets	0	0
Fair value measurements measured on a recurring basis | Exchange stock | Significant Unobservable Inputs (Level 3)
Assets
Other assets	0	0
Fair value measurements measured on a recurring basis | Other | Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Other assets	0	0
Fair value measurements measured on a recurring basis | Other | Significant Other Observable Inputs (Level 2)
Assets
Other assets	56,179,000	55,824,000
Fair value measurements measured on a recurring basis | Other | Significant Unobservable Inputs (Level 3)
Assets
Other assets	0	0
Fair Value | Fair value measurements measured on a recurring basis
Assets
Financial instruments owned, at fair value	2,297,070,000	2,117,579,000
Financial instruments owned and pledged	610,536,000	595,043,000
Other assets	100,811,000	98,364,000
Liabilities
Financial instruments sold, not yet purchased	2,846,453,000	2,384,598,000
Fair Value | Fair value measurements measured on a recurring basis | Currency forwards
Assets
Financial instruments owned, at fair value	2,234,000	17,790,000
Liabilities
Financial instruments sold, not yet purchased	4,958,000	7,026,000
Fair Value | Fair value measurements measured on a recurring basis | Options
Assets
Financial instruments owned, at fair value	9,210,000	7,045,000
Liabilities
Financial instruments sold, not yet purchased	15,548,000	5,839,000
Fair Value | Fair value measurements measured on a recurring basis | Equities
Assets
Financial instruments owned, at fair value	2,095,987,000	1,926,591,000
Financial instruments owned and pledged	571,997,000	586,251,000
Liabilities
Financial instruments sold, not yet purchased	2,716,628,000	2,203,432,000
Fair Value | Fair value measurements measured on a recurring basis | U.S. and Non-U.S. government obligations
Assets
Financial instruments owned, at fair value	19,007,000	22,783,000
Financial instruments owned and pledged	200,000	99,000
Liabilities
Financial instruments sold, not yet purchased	27,205,000
Fair Value | Fair value measurements measured on a recurring basis | Corporate Bonds
Assets
Financial instruments owned, at fair value	75,534,000	60,975,000
Liabilities
Financial instruments sold, not yet purchased	40,007,000
Fair Value | Fair value measurements measured on a recurring basis | Exchange traded notes
Assets
Financial instruments owned, at fair value	95,098,000	82,395,000
Financial instruments owned and pledged	38,339,000	8,693,000
Liabilities
Financial instruments sold, not yet purchased	42,107,000	55,762,000
Fair Value | Fair value measurements measured on a recurring basis | Equity investment
Assets
Other assets	42,478,000	40,588,000
Fair Value | Fair value measurements measured on a recurring basis | Exchange stock
Assets
Other assets	2,154,000	1,952,000
Fair Value | Fair value measurements measured on a recurring basis | Other
Assets
Other assets	$ 56,179,000	$ 55,824,000
SBI
Liabilities
Discount rate applied to cash flow forecasts to determine initial fair value of equity method investment.	15.00%
Market approach average price/earnings multiples of comparable companies to corroborate the income approach	14
Time period of projected income to determine fair value of equity method investment	5 years
Maximum
Liabilities
Annual payment receivable	$ 6,600,000

Financial Assets and Liabilit61

Financial Assets and Liabilities - Not measured at fair value (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Financial Instruments Not Measured at Fair Value
Cash and cash equivalents	$ 637,308	$ 532,887	$ 164,967	$ 181,415
Securities borrowed	1,232,048	1,471,172
Securities purchased under agreements to resell	602	0
Receivables from broker dealers and clearing organizations	1,434,039	972,018
Total assets	7,757,931	7,320,006
Short-term borrowings	20,944	27,883
Long-term borrowings	1,121,464	1,388,548
Securities loaned	936,061	754,687
Securities sold under agreements to repurchase	265,401	390,642
Payables to broker dealers and clearing organizations	648,788	716,205
Total liabilities	6,299,456	6,168,428
Carrying Value
Financial Instruments Not Measured at Fair Value
Cash and cash equivalents	637,308	532,887
Securities borrowed	1,232,048	1,471,172
Securities purchased under agreements to resell	602
Receivables from broker dealers and clearing organizations	1,434,039	972,018
Total assets	3,303,997	2,976,077
Short-term borrowings	20,944	27,883
Long-term borrowings	1,121,464	1,388,548
Securities loaned	936,061	754,687
Securities sold under agreements to repurchase	265,401	390,642
Payables to broker dealers and clearing organizations	648,788	716,205
Total liabilities	2,992,658	3,277,965
Fair value measurements not measured on a recurring basis | Fair Value
Financial Instruments Not Measured at Fair Value
Cash and cash equivalents	637,308	532,887
Securities borrowed	1,232,048	1,471,172
Securities purchased under agreements to resell	602
Receivables from broker dealers and clearing organizations	1,434,039	972,018
Total assets	3,303,997	2,976,077
Short-term borrowings	20,944	27,883
Long-term borrowings	1,193,167	1,465,489
Securities loaned	936,061	754,687
Securities sold under agreements to repurchase	265,401	390,642
Payables to broker dealers and clearing organizations	648,788	716,205
Total liabilities	3,064,361	3,354,906
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair value measurements not measured on a recurring basis | Fair Value
Financial Instruments Not Measured at Fair Value
Cash and cash equivalents	637,308	532,887
Securities borrowed	0	0
Securities purchased under agreements to resell	0
Receivables from broker dealers and clearing organizations	70,143	36,513
Total assets	707,451	569,400
Short-term borrowings	0	0
Long-term borrowings	0	0
Securities loaned	0	0
Securities sold under agreements to repurchase	0	0
Payables to broker dealers and clearing organizations	861	2,925
Total liabilities	861	2,925
Significant Other Observable Inputs (Level 2) | Fair value measurements not measured on a recurring basis | Fair Value
Financial Instruments Not Measured at Fair Value
Cash and cash equivalents	0	0
Securities borrowed	1,232,048	1,471,172
Securities purchased under agreements to resell	602
Receivables from broker dealers and clearing organizations	1,363,896	935,505
Total assets	2,596,546	2,406,677
Short-term borrowings	20,944	27,883
Long-term borrowings	1,193,167	1,465,489
Securities loaned	936,061	754,687
Securities sold under agreements to repurchase	265,401	390,642
Payables to broker dealers and clearing organizations	647,927	713,280
Total liabilities	3,063,500	3,351,981
Significant Unobservable Inputs (Level 3) | Fair value measurements not measured on a recurring basis | Fair Value
Financial Instruments Not Measured at Fair Value
Cash and cash equivalents	0	0
Securities borrowed	0	0
Securities purchased under agreements to resell	0
Receivables from broker dealers and clearing organizations	0	0
Total assets	0	0
Short-term borrowings	0	0
Long-term borrowings	0	0
Securities loaned	0	0
Securities sold under agreements to repurchase	0	0
Payables to broker dealers and clearing organizations	0	0
Total liabilities	$ 0	$ 0

Financial Assets and Liabilit62

Financial Assets and Liabilities - Level 3 financial instruments (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017
Fair value measurements measured on a recurring basis
Transfers of financial assets between levels	$ 0		$ 0
Assets
Financial instruments owned, at fair value	2,297,070,000	$ 2,117,579,000
Financial instruments owned, pledged as collateral	610,536,000	595,043,000
Other assets	100,811,000	98,364,000
Liabilities
Financial instruments sold, not yet purchased, at fair value	2,846,453,000	2,384,598,000
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	40,588,000	36,031,000
Purchases	0	3,000,000
Total Realized and Unrealized Gains / (Losses)	1,890,000	4,557,000
Net Transfers into (out of) Level 3	0	0
Settlement	0	(3,000,000)
Ending Balance	42,478,000	40,588,000
Change in Net Unrealized Gains / (Losses) On Investments Held	1,890,000	4,557,000
Equities
Assets
Financial instruments owned, pledged as collateral	571,997,000	586,251,000
U.S. and Non-U.S. government obligations
Assets
Financial instruments owned, pledged as collateral	200,000	99,000
Exchange traded notes
Assets
Financial instruments owned, pledged as collateral	38,339,000	8,693,000
Equity investment
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	40,588,000	36,031,000
Purchases	0	0
Total Realized and Unrealized Gains / (Losses)	1,890,000	4,557,000
Net Transfers into (out of) Level 3	0	0
Settlement	0	0
Ending Balance	42,478,000	40,588,000
Change in Net Unrealized Gains / (Losses) On Investments Held	1,890,000	4,557,000
Other
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	0	0
Purchases		3,000,000
Total Realized and Unrealized Gains / (Losses)		0
Net Transfers into (out of) Level 3		0
Settlement		(3,000,000)
Ending Balance		0
Change in Net Unrealized Gains / (Losses) On Investments Held		0
Fair value measurements measured on a recurring basis | Fair Value
Assets
Financial instruments owned, at fair value	2,297,070,000	2,117,579,000
Financial instruments owned, pledged as collateral	610,536,000	595,043,000
Other assets	100,811,000	98,364,000
Liabilities
Financial instruments sold, not yet purchased, at fair value	2,846,453,000	2,384,598,000
Fair value measurements measured on a recurring basis | Fair Value | Currency forwards
Assets
Financial instruments owned, at fair value	2,234,000	17,790,000
Liabilities
Financial instruments sold, not yet purchased, at fair value	4,958,000	7,026,000
Fair value measurements measured on a recurring basis | Fair Value | Options
Assets
Financial instruments owned, at fair value	9,210,000	7,045,000
Liabilities
Financial instruments sold, not yet purchased, at fair value	15,548,000	5,839,000
Fair value measurements measured on a recurring basis | Fair Value | Equities
Assets
Financial instruments owned, at fair value	2,095,987,000	1,926,591,000
Financial instruments owned, pledged as collateral	571,997,000	586,251,000
Liabilities
Financial instruments sold, not yet purchased, at fair value	2,716,628,000	2,203,432,000
Fair value measurements measured on a recurring basis | Fair Value | U.S. and Non-U.S. government obligations
Assets
Financial instruments owned, at fair value	19,007,000	22,783,000
Financial instruments owned, pledged as collateral	200,000	99,000
Liabilities
Financial instruments sold, not yet purchased, at fair value	27,205,000
Fair value measurements measured on a recurring basis | Fair Value | Corporate Bonds
Assets
Financial instruments owned, at fair value	75,534,000	60,975,000
Liabilities
Financial instruments sold, not yet purchased, at fair value	40,007,000
Fair value measurements measured on a recurring basis | Fair Value | Exchange traded notes
Assets
Financial instruments owned, at fair value	95,098,000	82,395,000
Financial instruments owned, pledged as collateral	38,339,000	8,693,000
Liabilities
Financial instruments sold, not yet purchased, at fair value	42,107,000	55,762,000
Fair value measurements measured on a recurring basis | Fair Value | Exchange stock
Assets
Other assets	2,154,000	1,952,000
Fair value measurements measured on a recurring basis | Fair Value | Equity investment
Assets
Other assets	42,478,000	40,588,000
Fair value measurements measured on a recurring basis | Fair Value | Other
Assets
Other assets	56,179,000	55,824,000
Fair value measurements measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Financial instruments owned, at fair value	1,031,258,000	785,185,000
Financial instruments owned, pledged as collateral	331,931,000	410,851,000
Other assets	2,154,000	1,952,000
Liabilities
Financial instruments sold, not yet purchased, at fair value	1,645,535,000	874,109,000
Fair value measurements measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Currency forwards
Assets
Financial instruments owned, at fair value	0	0
Liabilities
Financial instruments sold, not yet purchased, at fair value	0	0
Fair value measurements measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Options
Assets
Financial instruments owned, at fair value	9,210,000	7,045,000
Liabilities
Financial instruments sold, not yet purchased, at fair value	15,548,000	5,839,000
Fair value measurements measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Equities
Assets
Financial instruments owned, at fair value	956,518,000	758,596,000
Financial instruments owned, pledged as collateral	309,313,000	410,670,000
Liabilities
Financial instruments sold, not yet purchased, at fair value	1,584,268,000	847,816,000
Fair value measurements measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. and Non-U.S. government obligations
Assets
Financial instruments owned, at fair value	800,000	5,968,000
Financial instruments owned, pledged as collateral	200,000	99,000
Liabilities
Financial instruments sold, not yet purchased, at fair value	1,998,000
Fair value measurements measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Corporate Bonds
Assets
Financial instruments owned, at fair value	0	0
Liabilities
Financial instruments sold, not yet purchased, at fair value	40,007,000
Fair value measurements measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Exchange traded notes
Assets
Financial instruments owned, at fair value	64,730,000	13,576,000
Financial instruments owned, pledged as collateral	22,418,000	82,000
Liabilities
Financial instruments sold, not yet purchased, at fair value	3,714,000	1,514,000
Fair value measurements measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Exchange stock
Assets
Other assets	2,154,000	1,952,000
Fair value measurements measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Equity investment
Assets
Other assets	0	0
Fair value measurements measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other
Assets
Other assets	0	0
Fair value measurements measured on a recurring basis | Significant Other Observable Inputs (Level 2)
Assets
Financial instruments owned, at fair value	1,966,467,000	3,360,091,000
Financial instruments owned, at fair value, counterparty and cash collateral netting	(700,655,000)	(2,027,697,000)
Financial instruments owned, pledged as collateral	278,605,000	184,192,000
Other assets	56,179,000	55,824,000
Liabilities
Financial instruments sold, not yet purchased, at fair value	1,921,382,000	3,535,480,000
Financial instruments sold, not yet purchased, at fair value, counterparty and cash collateral netting	(720,464,000)	(2,024,991,000)
Fair value measurements measured on a recurring basis | Significant Other Observable Inputs (Level 2) | Currency forwards
Assets
Financial instruments owned, at fair value	702,889,000	2,045,487,000
Financial instruments owned, at fair value, counterparty and cash collateral netting	(700,655,000)	(2,027,697,000)
Liabilities
Financial instruments sold, not yet purchased, at fair value	725,422,000	2,032,017,000
Financial instruments sold, not yet purchased, at fair value, counterparty and cash collateral netting	(720,464,000)	(2,024,991,000)
Fair value measurements measured on a recurring basis | Significant Other Observable Inputs (Level 2) | Options
Assets
Financial instruments owned, at fair value	0	0
Liabilities
Financial instruments sold, not yet purchased, at fair value	0	0
Fair value measurements measured on a recurring basis | Significant Other Observable Inputs (Level 2) | Equities
Assets
Financial instruments owned, at fair value	1,139,469,000	1,167,995,000
Financial instruments owned, pledged as collateral	262,684,000	175,581,000
Liabilities
Financial instruments sold, not yet purchased, at fair value	1,132,360,000	1,355,616,000
Fair value measurements measured on a recurring basis | Significant Other Observable Inputs (Level 2) | U.S. and Non-U.S. government obligations
Assets
Financial instruments owned, at fair value	18,207,000	16,815,000
Financial instruments owned, pledged as collateral	0	0
Liabilities
Financial instruments sold, not yet purchased, at fair value	25,207,000
Fair value measurements measured on a recurring basis | Significant Other Observable Inputs (Level 2) | Corporate Bonds
Assets
Financial instruments owned, at fair value	75,534,000	60,975,000
Liabilities
Financial instruments sold, not yet purchased, at fair value	0
Fair value measurements measured on a recurring basis | Significant Other Observable Inputs (Level 2) | Exchange traded notes
Assets
Financial instruments owned, at fair value	30,368,000	68,819,000
Financial instruments owned, pledged as collateral	15,921,000	8,611,000
Liabilities
Financial instruments sold, not yet purchased, at fair value	38,393,000	54,248,000
Fair value measurements measured on a recurring basis | Significant Other Observable Inputs (Level 2) | Exchange stock
Assets
Other assets	0	0
Fair value measurements measured on a recurring basis | Significant Other Observable Inputs (Level 2) | Equity investment
Assets
Other assets	0	0
Fair value measurements measured on a recurring basis | Significant Other Observable Inputs (Level 2) | Other
Assets
Other assets	56,179,000	55,824,000
Fair value measurements measured on a recurring basis | Significant Unobservable Inputs (Level 3)
Assets
Financial instruments owned, at fair value	0	0
Financial instruments owned, pledged as collateral	0	0
Other assets	42,478,000	40,588,000
Liabilities
Financial instruments sold, not yet purchased, at fair value	0	0
Fair value measurements measured on a recurring basis | Significant Unobservable Inputs (Level 3) | Currency forwards
Assets
Financial instruments owned, at fair value	0	0
Liabilities
Financial instruments sold, not yet purchased, at fair value	0	0
Fair value measurements measured on a recurring basis | Significant Unobservable Inputs (Level 3) | Options
Assets
Financial instruments owned, at fair value	0	0
Liabilities
Financial instruments sold, not yet purchased, at fair value	0	0
Fair value measurements measured on a recurring basis | Significant Unobservable Inputs (Level 3) | Equities
Assets
Financial instruments owned, at fair value	0	0
Financial instruments owned, pledged as collateral	0	0
Liabilities
Financial instruments sold, not yet purchased, at fair value	0	0
Fair value measurements measured on a recurring basis | Significant Unobservable Inputs (Level 3) | U.S. and Non-U.S. government obligations
Assets
Financial instruments owned, at fair value	0	0
Financial instruments owned, pledged as collateral	0	0
Liabilities
Financial instruments sold, not yet purchased, at fair value	0
Fair value measurements measured on a recurring basis | Significant Unobservable Inputs (Level 3) | Corporate Bonds
Assets
Financial instruments owned, at fair value	0	0
Liabilities
Financial instruments sold, not yet purchased, at fair value	0
Fair value measurements measured on a recurring basis | Significant Unobservable Inputs (Level 3) | Exchange traded notes
Assets
Financial instruments owned, at fair value	0	0
Financial instruments owned, pledged as collateral	0	0
Liabilities
Financial instruments sold, not yet purchased, at fair value	0	0
Fair value measurements measured on a recurring basis | Significant Unobservable Inputs (Level 3) | Exchange stock
Assets
Other assets	0	0
Fair value measurements measured on a recurring basis | Significant Unobservable Inputs (Level 3) | Equity investment
Assets
Other assets	42,478,000	40,588,000
Fair value measurements measured on a recurring basis | Significant Unobservable Inputs (Level 3) | Other
Assets
Other assets	$ 0	$ 0

Financial Assets and Liabilit63

Financial Assets and Liabilities - Netting of Certain Financial Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Securities borrowed
Gross Amounts of Recognized Assets	$ 1,232,048	$ 1,471,172
Net Amounts of Assets Presented in the Consolidated Statement of Financial Condition	1,232,048	1,471,172
Gross Amounts Not Offset in the Statement of Financial Condition
Financial instruments	(1,202,760)	(1,418,672)
Cash collateral received	(2,624)	(13,318)
Net Amount	26,664	39,182
Securities purchased under agreements to resell
Gross Amounts of Recognized Assets	602
Net Amounts of Assets Presented in the Condensed Consolidated Statement of Financial Condition	602	0
Gross Amounts Not Offset In the Statement of Financial Condition
Financial Instruments	(602)
Cash Collateral Received	0
Net Amount	0
Gross Amounts Not Offset in the Consolidated Statement of Financial Condition
Securities Loaned, Collateral, Right to Reclaim Cash	884	10,776
Total
Gross Amounts of Recognized Assets	1,944,749	3,523,704
Gross Amounts Offset in the Consolidated Statement of Financial Condition	(700,655)	(2,027,697)
Net Amounts of Assets Presented in the Consolidated Statement of Financial Condition	1,244,094	1,496,007
Gross Amounts Not Offset in the Consolidated Statement of Financial Condition
Financial instruments	(1,203,363)	(1,418,717)
Cash collateral received	(2,624)	(13,318)
Net Amount	38,107	63,972
Currency forwards
Trading assets, at fair value
Gross Amounts of Recognized Assets	702,889	2,045,487
Gross Amounts Offset in the Consolidated Statement of Financial Condition	(700,655)	(2,027,697)
Net Amounts of Assets Presented in the Consolidated Statement of Financial Condition	2,234	17,790
Gross Amounts Not Offset in the Consolidated Statement of Financial Condition
Financial instruments	0	0
Cash collateral received	0	0
Net Amount	2,234	17,790
Options
Trading assets, at fair value
Gross Amounts of Recognized Assets	9,210	7,045
Gross Amounts Offset in the Consolidated Statement of Financial Condition	0	0
Net Amounts of Assets Presented in the Consolidated Statement of Financial Condition	9,210	7,045
Gross Amounts Not Offset in the Consolidated Statement of Financial Condition
Financial instruments	(1)	(45)
Cash collateral received	0	0
Net Amount	$ 9,209	$ 7,000

Financial Assets and Liabilit64

Financial Assets and Liabilities - Netting of Certain Financial Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Securities loaned
Gross Amounts of Recognized Liabilities	$ 936,061	$ 754,687
Net Amounts of Liabilities Presented in the Consolidated Statement of Financial Condition	936,061	754,687
Gross Amounts Not Offset in the Consolidated Statement of Financial Condition
Financial instruments	(929,457)	(737,731)
Cash collateral received	(884)	(10,776)
Net Amount	5,720	6,180
Securities sold under agreements to repurchase
Gross Amounts of Recognized Liabilities	265,401	390,642
Net Amounts of Liabilities Presented in the Consolidated Statement of Financial Condition	265,401	390,642
Gross Amounts Not Offset in the Consolidated Statement of Financial Condition
Financial instruments	(265,401)	(390,642)
Net Amount	0	0
Total
Gross Amounts of Recognized Liabilities	1,942,432	3,183,185
Gross Amounts Offset in the Consolidated Statement of Financial Condition	(720,464)	(2,024,991)
Net Amounts of Liabilities Presented in the Consolidated Statement of Financial Condition	1,221,968	1,158,194
Gross Amounts Not Offset in the Consolidated Statement of Financial Condition
Financial instruments	(1,194,859)	(1,128,429)
Cash collateral received	(884)	(10,776)
Net Amount	26,225	18,989
Currency forwards
Trading liabilities, at fair value:
Gross Amounts of Recognized Liabilities	725,422	2,032,017
Gross Amounts Offset in the Consolidated Statement of Financial Condition	(720,464)	(2,024,991)
Net Amounts of Assets Presented in the Consolidated Statement of Financial Condition	4,958	7,026
Gross Amounts Not Offset in the Consolidated Statement of Financial Condition
Financial instruments		0
Net Amount	4,958	7,026
Options
Trading liabilities, at fair value:
Gross Amounts of Recognized Liabilities	15,548	5,839
Gross Amounts Offset in the Consolidated Statement of Financial Condition		0
Net Amounts of Assets Presented in the Consolidated Statement of Financial Condition	15,548	5,839
Gross Amounts Not Offset in the Consolidated Statement of Financial Condition
Financial instruments	(1)	(56)
Net Amount	$ 15,547	$ 5,783

Financial Assets and Liabilit65

Financial Assets and Liabilities - Gross Obligations For Securities Lending Transactions (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Fair value measurements measured on a recurring basis
Remaining contractual maturity for repurchase agreements	$ 265,401	$ 390,642
Remaining contractual maturity for securities lending transactions	936,061	754,687
Overnight and Continuous
Fair value measurements measured on a recurring basis
Remaining contractual maturity for repurchase agreements	401	642
Remaining contractual maturity for securities lending transactions	936,061	754,687
Less than 30 Days
Fair value measurements measured on a recurring basis
Remaining contractual maturity for repurchase agreements	0	100,000
Remaining contractual maturity for securities lending transactions	0	0
30 To 60 Days
Fair value measurements measured on a recurring basis
Remaining contractual maturity for repurchase agreements	65,000	90,000
Remaining contractual maturity for securities lending transactions	0	0
61 To 90 Days
Fair value measurements measured on a recurring basis
Remaining contractual maturity for repurchase agreements	200,000	200,000
Remaining contractual maturity for securities lending transactions	0	0
Equities
Fair value measurements measured on a recurring basis
Remaining contractual maturity for repurchase agreements	265,401	390,000
Remaining contractual maturity for securities lending transactions	936,061	754,687
Equities | Overnight and Continuous
Fair value measurements measured on a recurring basis
Remaining contractual maturity for repurchase agreements	401	0
Remaining contractual maturity for securities lending transactions	936,061	754,687
Equities | Less than 30 Days
Fair value measurements measured on a recurring basis
Remaining contractual maturity for repurchase agreements	0	100,000
Remaining contractual maturity for securities lending transactions	0	0
Equities | 30 To 60 Days
Fair value measurements measured on a recurring basis
Remaining contractual maturity for repurchase agreements	65,000	90,000
Remaining contractual maturity for securities lending transactions	0	0
Equities | 61 To 90 Days
Fair value measurements measured on a recurring basis
Remaining contractual maturity for repurchase agreements	200,000	200,000
Remaining contractual maturity for securities lending transactions	0	0
U.S. and Non-U.S. government obligations
Fair value measurements measured on a recurring basis
Remaining contractual maturity for repurchase agreements	0	642
U.S. and Non-U.S. government obligations | Overnight and Continuous
Fair value measurements measured on a recurring basis
Remaining contractual maturity for repurchase agreements		642
U.S. and Non-U.S. government obligations | Less than 30 Days
Fair value measurements measured on a recurring basis
Remaining contractual maturity for repurchase agreements	0	0
U.S. and Non-U.S. government obligations | 30 To 60 Days
Fair value measurements measured on a recurring basis
Remaining contractual maturity for repurchase agreements	0	0
U.S. and Non-U.S. government obligations | 61 To 90 Days
Fair value measurements measured on a recurring basis
Remaining contractual maturity for repurchase agreements	$ 0	$ 0

Derivative Instruments - Fair V

Derivative Instruments - Fair Value of Derivative Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Equities futures | Not designated as hedging instruments | Receivables from broker dealers and clearing organizations
Fair value of derivative instruments on a gross basis
Derivatives Assets, Fair Value	$ 183	$ (505)
Derivatives Assets, Notional	4,836,630	1,985,770
Equities futures | Not designated as hedging instruments | Payables to broker dealers and clearing organizations
Fair value of derivative instruments on a gross basis
Derivatives Liabilities, Fair Value	208	(575)
Derivatives Liabilities, Notional	139,033	142,658
Commodity futures | Not designated as hedging instruments | Receivables from broker dealers and clearing organizations
Fair value of derivative instruments on a gross basis
Derivatives Assets, Fair Value	39,965	971
Derivatives Assets, Notional	20,971,297	21,231,001
Commodity futures | Not designated as hedging instruments | Payables to broker dealers and clearing organizations
Fair value of derivative instruments on a gross basis
Derivatives Liabilities, Fair Value	645	(1,602)
Derivatives Liabilities, Notional	118,427	130,042
Currency futures | Not designated as hedging instruments | Receivables from broker dealers and clearing organizations
Fair value of derivative instruments on a gross basis
Derivatives Assets, Fair Value	32,042	26,548
Derivatives Assets, Notional	2,075,544	3,994,412
Currency futures | Not designated as hedging instruments | Payables to broker dealers and clearing organizations
Fair value of derivative instruments on a gross basis
Derivatives Liabilities, Fair Value	(3,279)	(13,947)
Derivatives Liabilities, Notional	2,531,734	7,756,958
Fixed Income futures | Not designated as hedging instruments | Receivables from broker dealers and clearing organizations
Fair value of derivative instruments on a gross basis
Derivatives Assets, Fair Value	23	73
Derivatives Assets, Notional	10,096	44,395
Fixed Income futures | Not designated as hedging instruments | Payables to broker dealers and clearing organizations
Fair value of derivative instruments on a gross basis
Derivatives Liabilities, Fair Value	(169)	(1)
Derivatives Liabilities, Notional	13,016	2,584
Currency forwards
Fair value of derivative instruments on a gross basis
Derivatives Assets, Fair Value	702,889	2,045,487
Derivatives Liabilities, Fair Value	725,422	2,032,017
Currency forwards | Not designated as hedging instruments | Financial instruments owned
Fair value of derivative instruments on a gross basis
Derivatives Assets, Fair Value	702,889	2,045,487
Derivatives Assets, Notional	100,689,302	124,000,221
Currency forwards | Not designated as hedging instruments | Financial instruments sold, not yet purchased
Fair value of derivative instruments on a gross basis
Derivatives Liabilities, Fair Value	725,058	2,032,017
Derivatives Liabilities, Notional	100,700,387	123,993,234
Currency forwards | Derivative instruments designed as hedging instruments: | Financial instruments sold, not yet purchased
Fair value of derivative instruments on a gross basis
Derivatives Liabilities, Fair Value	(364)	(514)
Derivatives Liabilities, Notional	15,964	16,115
Options
Fair value of derivative instruments on a gross basis
Derivatives Assets, Fair Value	9,210	7,045
Derivatives Liabilities, Fair Value	15,548	5,839
Options | Not designated as hedging instruments | Financial instruments owned
Fair value of derivative instruments on a gross basis
Derivatives Assets, Fair Value	9,210	7,045
Derivatives Assets, Notional	793,423	682,369
Options | Not designated as hedging instruments | Financial instruments sold, not yet purchased
Fair value of derivative instruments on a gross basis
Derivatives Liabilities, Fair Value	15,548	5,839
Derivatives Liabilities, Notional	$ 769,273	$ 681,147

Derivative Instruments - Gain F

Derivative Instruments - Gain From Derivative Instruments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Not designated as hedging instruments
Gain impact of derivative instruments not designated as hedging instruments
Gain impact that derivative instruments not designated as hedging instruments had on results of operations	$ (349,402)	$ 114,210
Derivative instruments designed as hedging instruments:
Gain impact of derivative instruments not designated as hedging instruments
Net gain from derivative instruments, which are recorded in accumulated other comprehensive income	150	0
Futures | Not designated as hedging instruments
Gain impact of derivative instruments not designated as hedging instruments
Gain impact that derivative instruments not designated as hedging instruments had on results of operations	(436,414)	165,590
Currency forwards | Not designated as hedging instruments
Gain impact of derivative instruments not designated as hedging instruments
Gain impact that derivative instruments not designated as hedging instruments had on results of operations	85,910	(51,381)
Options | Not designated as hedging instruments
Gain impact of derivative instruments not designated as hedging instruments
Gain impact that derivative instruments not designated as hedging instruments had on results of operations	$ 1,102	$ 1

Revenues from Contracts with 68

Revenues from Contracts with Customers (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Total revenue	$ 815,053	$ 147,287
Receivables related to revenue from contracts with customers	5,600		$ 7,100
Market Making
Disaggregation of Revenue [Line Items]
Revenues from contract with customers	8,501
Other sources of revenue	424,035
Total revenue	432,536	144,448
Market Making | Services transferred at a point in time
Disaggregation of Revenue [Line Items]
Total revenue	432,536
Market Making | Services transferred over time
Disaggregation of Revenue [Line Items]
Total revenue	0
Market Making | Commissions, net
Disaggregation of Revenue [Line Items]
Revenues from contract with customers	8,501
Market Making | Technology services
Disaggregation of Revenue [Line Items]
Revenues from contract with customers	0
Execution Services
Disaggregation of Revenue [Line Items]
Revenues from contract with customers	45,343
Other sources of revenue	338,436
Total revenue	383,779	2,779
Execution Services | Services transferred at a point in time
Disaggregation of Revenue [Line Items]
Total revenue	381,444
Execution Services | Services transferred over time
Disaggregation of Revenue [Line Items]
Total revenue	2,335
Execution Services | Commissions, net
Disaggregation of Revenue [Line Items]
Revenues from contract with customers	43,008
Execution Services | Technology services
Disaggregation of Revenue [Line Items]
Revenues from contract with customers	2,335
Corporate
Disaggregation of Revenue [Line Items]
Revenues from contract with customers	0
Other sources of revenue	(1,262)
Total revenue	(1,262)	$ 60
Corporate | Services transferred at a point in time
Disaggregation of Revenue [Line Items]
Total revenue	(1,262)
Corporate | Services transferred over time
Disaggregation of Revenue [Line Items]
Total revenue	0
Corporate | Commissions, net
Disaggregation of Revenue [Line Items]
Revenues from contract with customers	0
Corporate | Technology services
Disaggregation of Revenue [Line Items]
Revenues from contract with customers	$ 0

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Provision for income taxes	$ 58,514	$ 2,808
Effective tax rate (as a percent)	12.50%	11.80%
Current income taxes receivable	$ 103,600		$ 115,200
Current taxes payable	52,600		7,600
Deferred tax asset, alternative minimum tax	600		600
Operating loss carryforwards	231,800		231,800
Deferred tax asset, non-U.S. operating loss carryforward	$ 43,500		43,500
Tax cuts and jobs act, incomplete accounting change in rate, provisional income tax expense			$ 90,600

Commitments, Contingencies an70

Commitments, Contingencies and Guarantees (Details) € in Millions, $ in Millions	Dec. 31, 2017USD ($)	Dec. 31, 2017EUR (€)	Dec. 31, 2015USD ($)	Dec. 31, 2015EUR (€)
Litigation
Amount of fine	$ 3.9	€ 3.3	$ 5.4	€ 5

Capital Structure (Details)

Capital Structure (Details) $ in Millions	Aug. 10, 2017USD ($)shares	Jul. 20, 2017USD ($)shares	Feb. 28, 2018shares	Feb. 28, 2017shares	Mar. 31, 2018Voteclass	Apr. 21, 2015shares
Class of Stock [Line Items]
Number of classes of common stock | class					4
Virtu Financial
Class of Stock [Line Items]
Ownership interest (as a percent)					49.10%
VFH
Class of Stock [Line Items]
Issuance of common stock in connection with employee exchanges (in shares)			795,521	683,762
Common stock exchange ratio					1
Class A | 2015 Management Incentive Plan
Class of Stock [Line Items]
Number of shares of stock authorized						16,000,000
Class A common stock and Class C common stock
Class of Stock [Line Items]
Number of votes | Vote					1
Class B common stock and Class D common stock
Class of Stock [Line Items]
Number of votes | Vote					10
NIH Investment Agreement | Class A
Class of Stock [Line Items]
Number of shares of stock issued	338,124
Aggregate purchase price | $	$ 5.2
KCG | Aranda | Class A
Class of Stock [Line Items]
Number of shares of stock issued		6,346,155
Aggregate purchase price | $		$ 99
KCG | NIH Investment Agreement
Class of Stock [Line Items]
Number of shares of stock issued		39,725,979
Aggregate purchase price | $		$ 613.5
KCG | NIH Investment Agreement | Class A
Class of Stock [Line Items]
Number of shares of stock issued	338,124
Aggregate purchase price | $	$ 5.2
KCG | Temasek Investment | Class A
Class of Stock [Line Items]
Number of shares of stock issued	1,666,666
Aggregate purchase price | $	$ 26

Share-based Compensation (Detai

Share-based Compensation (Details) - USD ($)	Apr. 21, 2015	Apr. 15, 2015	Jul. 08, 2011	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-voting common interest units outstanding (in shares)				11,512,297		12,301,067
Number of non-voting common interest units forfeited or repurchased (in shares)				788,770		729,272
Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Accrued compensation expense				$ 3,900,000	$ 4,700,000
Granted (in shares)				594,536
Granted during period, value				$ 11,300,000
Class B interests | East MIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			4 years
Non-voting common interest units (formerly Class B interests)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expense recognized				0	200,000
Unrecognized share-based compensation expense				$ 0		$ 100,000
Weighted average period for compensation expense expected to be recognized				0 years		9 months 18 days
Capitalized software development costs				$ 0	10,000
Non-voting common interest units (formerly Class B interests) | East MIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amortization expense related to share based compensation				10,000	0
Non-voting common interest units (formerly Class A 2 profits interests)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expense recognized				0	200,000
Unrecognized share-based compensation expense				$ 0		$ 100,000
Weighted average period for compensation expense expected to be recognized				0 years		1 month 6 days
Non-voting common interest units (formerly Class A 2 profits interests) | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		4 years
Non-qualified stock options | 2015 Management Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
Expiration period	10 years
Expense recognized				$ 1,400,000	$ 1,400,000
Unrecognized share-based compensation expense				$ 6,100,000		$ 7,500,000
Weighted average period for compensation expense expected to be recognized				1 year 1 month 6 days		1 year 3 months 18 days
Forfeited or repurchased (in shares)					(195,000)
Outstanding (in shares)				7,783,000	8,234,000	8,234,000
Forfeited or expired (in shares)					(195,000)
Outstanding (in shares)				7,051,000	8,039,000	7,783,000	8,234,000
Weighted Average Exercise Price Per Share
Outstanding (in dollars per share)				$ 19	$ 19	$ 19
Exercised (in dollars per share)				19
Outstanding (in dollars per share)				$ 19	$ 19	$ 19	$ 19
Activity
Exercised (in shares)				(732,000)
Weighted Average Remaining Life, outstanding
Weighted Average Remaining Life				7 years 18 days	8 years 18 days	7 years 3 months 15 days	8 years 3 months 15 days
Options Exercisable, Number of Options (in shares)				3,182,000	2,009,750	3,891,500	2,058,500
Options Exercisable, Weighted Average Exercise Price (in dollars per share)				$ 19	$ 19	$ 19	$ 19
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based compensation expense				$ 34,800,000		$ 14,300,000
Weighted average period for compensation expense expected to be recognized				1 year 10 months 24 days		1 year 6 months
Restricted stock units | Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expense recognized				$ 4,000,000	$ 2,600,000
Restricted stock units | 2015 Management Incentive Plan
Activity
Outstanding (in shares)				853,047	1,573,441	1,573,441
Granted (in shares)				1,044,690	0
Forfeited (in shares)				(30,626)	(95,481)
Vested (in shares)				0	0
Outstanding (in shares)				1,867,111	1,477,960	853,047	1,573,441
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Outstanding (in dollars per share)				$ 17.94	$ 18.28	$ 18.28
Granted (in dollars per share)				20.64	0
Forfeited (in dollars per share)				18.52	18.38
Vested (in dollars per share)				0	0
Outstanding (in dollars per share)				$ 18.85	$ 18.28	$ 17.94	$ 18.28
Restricted stock units | 2015 Management Incentive Plan | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				4 years

Regulatory Requirement (Details

Regulatory Requirement (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)trading_unitsubsidiary	Dec. 31, 2017USD ($)	Nov. 03, 2017broker_dealer
Entity Information [Line Items]
Number of broker-dealer subsidiaries	3		3
Regulatory Capital	$ 1,000
Virtu Americas LLC
Entity Information [Line Items]
Regulatory Capital	411,168	$ 379,875
Minimum Net Capital Required	1,000	1,000
Excess Regulatory Capital	410,168	378,875
Virtu Financial BD LLC
Entity Information [Line Items]
Regulatory Capital	88,280	40,683
Minimum Net Capital Required	1,000	1,000
Excess Regulatory Capital	87,280	39,683
Virtu Financial Capital Markets LLC
Entity Information [Line Items]
Regulatory Capital	8,563	8,308
Minimum Net Capital Required	4,696	5,114
Excess Regulatory Capital	3,867	3,194
Minimum capital required to be maintained in connection with the operation of the Company's DMM business	3,700	$ 4,100
Required amount under exchange rules	$ 1,000
Required amount under exchange rules as percentage of market value	15.00%
Number of trading units whose market value is considered to calculate required net capital under exchange act | trading_unit	60

Geographic Information and Bu74

Geographic Information and Business Segments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Total revenues by geographic area
Revenues	$ 815,053	$ 147,287
United States
Total revenues by geographic area
Revenues	743,152	91,987
Ireland
Total revenues by geographic area
Revenues	14,023	28,251
United Kingdom
Total revenues by geographic area
Revenues	11,600	0
Singapore
Total revenues by geographic area
Revenues	46,200	27,006
Others
Total revenues by geographic area
Revenues	$ 78	$ 43

Geographic Information and Bu75

Geographic Information and Business Segments - Segments (Details) $ in Thousands	Jul. 19, 2017businesssegment	Mar. 31, 2018USD ($)	Sep. 30, 2017segment	Mar. 31, 2017USD ($)
Segment reporting
Number of businesses Company is managed and operated as | business	1
Number of reportable segments | segment	1
Number of operating segments | segment			3
Revenues		$ 815,053		$ 147,287
Income (loss) before income taxes and noncontrolling interest		468,536		23,882
Market Making
Segment reporting
Revenues		432,536		144,448
Income (loss) before income taxes and noncontrolling interest		163,163		23,465
Execution Services
Segment reporting
Revenues		383,779		2,779
Income (loss) before income taxes and noncontrolling interest		331,185		489
Corporate
Segment reporting
Revenues		(1,262)		60
Income (loss) before income taxes and noncontrolling interest		$ (25,812)		$ (72)

Related Party Transactions (Det

Related Party Transactions (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)joint_venture	Mar. 31, 2017USD ($)	Dec. 31, 2017USD ($)
Related Party Transactions
Payable to affiliates	$ 1,300		$ 100
Securities loaned	936,061		754,687
Securities borrowed	1,232,048		1,471,172
Industrial and Commercial Bank of China (“ICBC”)
Related Party Transactions
Securities loaned	700		1,100
Securities borrowed			$ 23,100
Dell
Related Party Transactions
Payments for purchases	600	$ 800
Markit Group Holdings Limited
Related Party Transactions
Payments for purchases	400
Level 3
Related Party Transactions
Payments for purchases	700	700
Two microwave communication network JVs
Related Party Transactions
Payments to related party	$ 5,600	100
Number of microwave communication network JVs the Company makes payments to | joint_venture	2
SBI
Related Party Transactions
Payments to related party	$ 2,300	$ 1,500

Subsequent Events (Details)

Subsequent Events (Details) - USD ($)	May 04, 2018	Apr. 19, 2018	Apr. 13, 2018	Mar. 31, 2018
Senior Secured Credit Facility
Subsequent events
Maximum borrowing capacity				$ 524,000,000
Subsequent Events
Subsequent events
Proceeds from tax distribution			$ 39,300,000
Subsequent Events | Class A
Subsequent events
Dividends declared (in dollars per share)	$ 0.24
Subsequent Events | Senior Secured Credit Facility
Subsequent events
Repayments of debt		$ 100,000,000