Global Brokerage (GLBR) 10-Q 5 Aug 16 2016 Q2 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	6 Months Ended
	Jun. 30, 2016	Aug. 03, 2016
Document Information [Line Items]
Entity Registrant Name	FXCM Inc.
Entity Central Index Key	1,499,912
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-Q
Document Period End Date	Jun. 30, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q2
Trading Symbol	FXCM
Amendment Flag	false
Common Stock - Class A
Document Information [Line Items]
Entity Common Stock, Shares Outstanding (in shares)		5,602,534
Common Stock - Class B
Document Information [Line Items]
Entity Common Stock, Shares Outstanding (in shares)		25

Condensed Consolidated Statemen

Condensed Consolidated Statements of Financial Condition (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Current assets
Cash and cash equivalents	$ 208,707	$ 203,854
Cash and cash equivalents, held for customers	662,392	685,043
Due from brokers	2,071	3,781
Accounts receivable, net	1,468	1,636
Tax receivable	21	1,766
Current assets held for sale	199,730	233,937
Total current assets	1,074,389	1,130,017
Deferred tax asset	15	14
Office, communication and computer equipment, net	35,505	35,891
Goodwill	25,363	28,080
Other intangible assets, net	9,670	13,782
Notes receivable	0	7,881
Other assets	12,393	11,421
Total assets	1,157,335	1,227,086
Current liabilities
Customer account liabilities	662,392	685,043
Accounts payable and accrued expenses	41,597	38,298
Due to brokers	12,176	1,073
Due to related parties pursuant to tax receivable agreement	0	145
Current liabilities held for sale	13,690	14,510
Total current liabilities	729,855	739,069
Deferred tax liability	280	719
Senior convertible notes	157,795	154,255
Credit Agreement	180,153	147,262
Derivative liability — Letter Agreement	209,458	448,458
Other liabilities	13,543	16,044
Total liabilities	1,291,084	1,505,807
Commitments and Contingencies (See Note 14)
Stockholders’ Deficit
Additional paid-in capital	268,112	267,369
Accumulated deficit	(421,414)	(531,550)
Accumulated other comprehensive (loss) income	(766)	1,004
Total stockholders’ deficit, FXCM Inc.	(154,011)	(263,120)
Non-controlling interests	20,262	(15,601)
Total stockholders’ deficit	(133,749)	(278,721)
Total liabilities and stockholders’ deficit	1,157,335	1,227,086
Common Stock - Class A
Stockholders’ Deficit
Common stock	56	56
Common Stock - Class B
Stockholders’ Deficit
Common stock	$ 1	$ 1

Condensed Consolidated Stateme3

Condensed Consolidated Statements of Financial Condition (Unaudited) (Parenthetical) - $ / shares	Jun. 30, 2016	Dec. 31, 2015
Common Stock - Class A
Common stock, par value (USD per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	3,000,000,000	3,000,000,000
Common stock, shares issued (in shares)	5,602,534	5,602,534
Common stock, shares outstanding (in shares)	5,602,534	5,602,534
Common Stock - Class B
Common stock, par value (USD per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	1,000,000	1,000,000
Common stock, shares issued (in shares)	25	25
Common stock, shares outstanding (in shares)	25	25

Condensed Consolidated Stateme4

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Revenues
Trading revenue		$ 68,958	$ 59,211	$ 138,705	$ 128,425
Interest income		581	416	1,109	738
Brokerage interest expense		(229)	(173)	(427)	(377)
Net interest revenue		352	243	682	361
Other income		1,246	1,058	2,684	146,916
Total net revenues		70,556	60,512	142,071	275,702
Operating Expenses
Compensation and benefits		24,351	23,457	49,177	48,496
Referring broker fees		8,933	14,601	19,579	30,670
Advertising and marketing		4,816	3,483	10,284	6,300
Communication and technology		6,516	9,243	14,121	18,760
Trading costs, prime brokerage and clearing fees		849	960	1,737	2,100
General and administrative		24,879	12,718	38,980	26,373
Bad debt (recovery) expense		(141)	388	(141)	257,303
Depreciation and amortization		6,949	6,800	14,193	13,820
Goodwill impairment loss		0	0	0	9,513
Total operating expenses		77,152	71,650	147,930	413,335
Operating loss		(6,596)	(11,138)	(5,859)	(137,633)
Other Income (Expense)
Gain (loss) on derivative liabilities — Letter & Credit Agreements		116,529	(99,867)	227,360	(392,296)
Loss on equity method investments, net		149	37	338	188
Interest on borrowings		21,202	44,291	41,755	74,850
Income (loss) from continuing operations before income taxes		88,582	(155,333)	179,408	(604,967)
Income tax (benefit) provision		(439)	1,559	143	181,321
Income (loss) from continuing operations		89,021	(156,892)	179,265	(786,288)
(Loss) income from discontinued operations, net of tax		(518)	5,665	(31,586)	(92,933)
Net income (loss)		88,503	(151,227)	147,679	(879,221)
Net income (loss) attributable to FXCM Inc.		60,401	(95,811)	110,136	(522,628)
Income (loss) from continuing operations attributable to FXCM Inc.		60,495	(98,886)	121,765	(492,211)
(Loss) income from discontinued operations attributable to FXCM Inc.		$ (94)	$ 3,075	$ (11,629)	$ (30,417)
Weighted average shares of Class A common stock outstanding — Basic and Diluted (in shares)	[1]	5,603	4,871	5,603	4,790
FXCM Holdings LLC
Other Income (Expense)
Net income (loss) attributable to non-controlling interest		$ 28,452	$ (56,313)	$ 51,904	$ (313,688)
Other Non-Controlling Interest
Other Income (Expense)
Net income (loss) attributable to non-controlling interest		(350)	897	(14,361)	(42,905)
Common Stock - Class A
Other Income (Expense)
Net income (loss) attributable to FXCM Inc.		$ 60,401	$ (95,811)	$ 110,136	$ (522,628)
Net income (loss) per share attributable to stockholders of Class A common stock of FXCM Inc. — Basic and Diluted
Continuing operations (USD per share)		$ 10.80	$ (20.30)	$ 21.73	$ (102.76)
Discontinued operations (USD per share)		(0.02)	0.63	(2.08)	(6.35)
Net income (loss) attributable to FXCM Inc. (USD per share)		$ 10.78	$ (19.67)	$ 19.65	$ (109.11)
[1]	Prior periods are adjusted to reflect the impact of the one-for-ten reverse stock split that became effective on October 1, 2015

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Operations (Unaudited) (Parenthetical)	Oct. 01, 2015	Apr. 15, 2015
Common Stock - Class A
Reverse stock split (in shares)	0.1	0.1

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest [Abstract]
Net income (loss)	$ 88,503	$ (151,227)	$ 147,679	$ (879,221)
Other comprehensive (loss) income
Foreign currency translation (loss) gain	(2,542)	2,958	(2,595)	(882)
Realization of cumulative translation adjustment	0	23,407	0	23,407
Other comprehensive (loss) income, net of tax	(2,542)	26,365	(2,595)	22,525
Comprehensive income (loss)	85,961	(124,862)	145,084	(856,696)
Comprehensive income (loss) attributable to FXCM Inc.	58,675	(79,558)	108,366	(508,733)
FXCM Holdings LLC
Other comprehensive (loss) income
Comprehensive income attributable to non-controlling interest	27,640	(46,206)	51,071	(305,052)
Other Non-Controlling Interest
Other comprehensive (loss) income
Comprehensive income attributable to non-controlling interest	$ (354)	$ 902	$ (14,353)	$ (42,911)

Condensed Consolidated Stateme7

Condensed Consolidated Statement of Stockholders' Deficit (Unaudited) - 6 months ended Jun. 30, 2016 - USD ($) $ in Thousands	Total	Non- controlling Interests	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)	Additional Paid-in Capital	Common Stock - Class ACommon Stock	Common Stock - Class BCommon Stock
Beginning Balance at Dec. 31, 2015	$ (278,721)	$ (15,601)	$ (531,550)	$ 1,004	$ 267,369	$ 56	$ 1
Beginning Balance (in shares) at Dec. 31, 2015						5,602,534	25
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	147,679	37,543	110,136
Other comprehensive loss, net of tax	(2,595)	(825)		(1,770)
Comprehensive income (loss)	145,084	36,718	110,136	(1,770)
Equity-based compensation	1,091	348			743
Distributions — non-controlling members	(1,203)	(1,203)
Ending Balance at Jun. 30, 2016	$ (133,749)	$ 20,262	$ (421,414)	$ (766)	$ 268,112	$ 56	$ 1
Ending Balance (In shares) at Jun. 30, 2016						5,602,534	25

Condensed Consolidated Stateme8

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Cash Flows From Operating Activities
Net income (loss)	$ 147,679	$ (879,221)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities
Depreciation and amortization	14,193	26,179
Equity-based compensation	1,044	3,031
Deferred tax (benefit) expense	(386)	187,150
Goodwill impairment losses	0	85,847
Impairment losses on held for sale assets	31,997	7,330
(Gain) loss on derivative liabilities — Letter & Credit Agreements	(227,360)	392,296
Amortization of deferred bond discount	2,935	2,761
Amortization of deferred financing cost	604	2,049
Amortization of original issue discount — Credit Agreement	17,070	40,687
Amortization of issuance fee, deferred financing fee and acquisition costs — Credit Agreement	4,323	9,621
Loss on equity method investments, net	245	689
Gain on disposition of equity method investment	(679)	0
Provision for debt forgiveness	8,249	0
Gain on business disposition	0	1,978
Transaction costs associated with business dispositions	0	(4,607)
Due to related parties pursuant to tax receivable agreement	44	(145,224)
Changes in operating assets and liabilities
Cash and cash equivalents, held for customers	21,345	239,972
Due from brokers	5,394	10,416
Accounts receivable, net	(136)	(1,485)
Tax receivable, net	1,745	(49)
Other assets	(371)	(6,981)
Customer account liabilities	(22,651)	(239,791)
Accounts payable and accrued expenses	1,966	(1,068)
Other liabilities	(1,516)	5,021
Payments for tax receivable agreement	(188)	(5,352)
Due to brokers	11,359	(2,741)
Securities sold, not yet purchased	272	(517)
Foreign currency remeasurement loss	(133)	(817)
Net cash provided by (used in) operating activities	17,044	(276,782)
Cash Flows From Investing Activities
Purchases of office, communication and computer equipment, net	(9,984)	(8,788)
Proceeds from sale of office, communication and computer equipment	0	499
Purchase of intangible assets	(1,000)	0
Proceeds from notes receivable	0	1,500
Proceeds from business dispositions, net of cash	0	47,065
Net cash (used in) provided by investing activities	(10,984)	40,276
Cash Flows From Financing Activities
Distributions to non-controlling members	(104)	(11,819)
Payments on borrowings under the Revolving credit agreement	0	(25,000)
Proceeds from the Leucadia Transaction	0	279,000
Principal payments on borrowings under the Credit Agreement	(141)	(81,633)
Debt acquisition costs — Credit Agreement	0	(1,876)
Proceeds from issuance of stock options	0	321
Net cash (used in) provided by financing activities	(245)	158,993
Effect of foreign currency exchange rate changes on cash and cash equivalents	1,723	(410)
Net increase (decrease) in cash and cash equivalents	7,538	(77,923)
Cash and cash equivalents
Beginning of year	214,640	338,814
End of period	222,178	260,891
Supplemental disclosures of cash flow activities
Cash (received) paid for taxes	(205)	47
Cash paid for interest	18,033	14,921
Supplemental disclosure of non-cash investing activities
Exchange of Holdings Units for shares of Class A common stock	0	3,200
Deferred payment for purchase of intangible assets	0	6,000
Supplemental disclosure of non-cash financing activities
Non-cash distribution — non-controlling members	1,099	0
Discontinued Operations
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities
Depreciation and amortization	0	12,359
Equity-based compensation	0	1,494
Deferred tax (benefit) expense	0	5,663
Goodwill impairment losses	0	54,865
Impairment losses on held for sale assets	31,997	28,799
Loss on equity method investments, net	93	(501)
Gain on disposition of equity method investment	679	0
Cash Flows From Investing Activities
Purchases of office, communication and computer equipment, net	(120)	(193)
Proceeds from sale of office, communication and computer equipment	$ 0	$ 499

Description of Business and Bas

Description of Business and Basis of Presentation	6 Months Ended
	Jun. 30, 2016
Accounting Policies [Abstract]
Description of Business and Basis of Presentation	Description of Business and Basis of Presentation Description of Business FXCM Inc. (the “Corporation”), a holding company, is an online provider of foreign exchange (“FX”) trading, contracts for difference ("CFD") trading, spread betting and related services to retail and institutional customers worldwide. The Corporation operates through its managing membership interest in FXCM Holdings, LLC (“Holdings”), the Corporation’s sole operating asset. Holdings is a majority-owned, controlled and consolidated subsidiary of the Corporation. In January 2015, Holdings transferred its interest in its operating subsidiaries to FXCM Newco, LLC (“Newco”), a wholly-owned subsidiary of Holdings, formed in connection with the financing arrangement entered into with Leucadia National Corporation ("Leucadia") (the "Leucadia Transaction") (see Note 12). As used in these notes, the term “Company” collectively refers to the Corporation, Holdings and subsidiaries of Holdings. Discontinued Operations During the first quarter of 2015, the Company commenced the process of disposing of its interests in certain retail and institutional trading businesses. The retail businesses are FXCM Asia Limited, FXCM Japan Securities Co., Ltd. and the equity trading business of FXCM Securities Limited. The institutional businesses are Faros Trading LLC, Lucid Markets Trading Limited, V3 Markets, LLC and the Company's equity interest in FastMatch, Inc. ("FastMatch"). In April 2015, the Company completed the sale of FXCM Japan Securities Co., Ltd. and Faros Trading LLC. In September 2015, the Company completed the sale of FXCM Asia Limited. In December 2015, the Company completed the sale of the equity trading business of FXCM Securities Limited. The Company remains committed to a plan to sell the remaining businesses which continue to be actively marketed. As a result, these businesses are considered to be held for sale and their results of operations have been reported as discontinued operations (see Note 4). Reverse Stock Split A one-for-ten reverse split of the Corporation's issued and outstanding Class A common stock (the "Reverse Stock Split") became effective at the opening of trading on the NYSE on October 1, 2015 (the "Effective Date"). As of the Effective Date, every ten shares of issued and outstanding Class A common stock were combined into one newly issued share of Class A common stock. No fractional shares were issued in connection with the Reverse Stock Split. All references in this Quarterly Report to number of Class A common shares, number of Holdings Units, price per share and weighted average shares of Class A common stock have been adjusted to reflect the Reverse Stock Split on a retroactive basis for the prior period presented, unless otherwise noted. Basis of Presentation Basis of Consolidation The accompanying condensed consolidated financial statements are presented in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). The Company consolidates those entities in which it is the primary beneficiary of a variable interest entity ("VIE") as required by Financial Accounting Standards Board (“FASB”) Accounting Standards Codification Topic (“ASC”) 810, Consolidations (“ASC 810”), or entities where it has a controlling interest. Intercompany accounts and transactions are eliminated in consolidation. As indicated above, in January 2015, Holdings transferred its interest in its operating subsidiaries to Newco, a wholly-owned subsidiary of Holdings formed in connection with the Leucadia Transaction (see Note 12). The Leucadia Transaction provided the financing needed in order for the operating subsidiaries of Holdings and Newco to maintain compliance with regulatory capital requirements and continue operations. The Company determined that Newco is a VIE and concluded that Holdings is the primary beneficiary of Newco since Holdings has the ability to direct the activities of Newco that most significantly impact Newco’s economic performance and the obligation to absorb losses of Newco or the right to receive benefits from Newco that could be significant to Newco. As a result, Holdings consolidates the financial results of Newco. The Corporation records a non-controlling interest for the economic interest in Holdings not owned by the Corporation. The Corporation’s and the non-controlling unit holders’ economic interest in Holdings was 67.9% and 32.1% , respectively, as of both June 30, 2016 and December 31, 2015 . The Company’s condensed consolidated financial statements include the following significant subsidiaries of Holdings: FXCM Newco, LLC (“Newco”) FXCM Global Services, LLC (“Global Services”) Forex Capital Markets LLC (“US”) FXCM Asia Limited** (“HK”) Forex Capital Markets Limited (“UK LTD”) FXCM Australia Pty. Limited (“Australia”) ODL Group Limited (“ODL”) FXCM Securities Limited*** (“FSL”) FXCM Japan Securities Co., Ltd.* (“FXCMJ”) FXCM UK Merger Limited (“Merger”) Lucid Markets Trading Limited (“Lucid”) Lucid Markets LLP (“Lucid LLP”) Faros Trading LLC* (“Faros”) V3 Markets, LLC (“V3”) * Sold by the Company in April 2015 ** Sold by the Company in September 2015 *** Sold by the Company in December 2015 Net income or loss attributable to the non-controlling interest in Holdings in the condensed consolidated statements of operations represents the portion of earnings or loss attributable to the economic interest in Holdings held by the non-controlling unit holders. Net income or loss attributable to other non-controlling interests in the condensed consolidated statements of operations represents the portion of net income or loss attributable to the non-controlling interests of Lucid, Faros (prior to the sale of Faros' operations in the second quarter of 2015), V3 and other consolidated entities. Net income or loss attributable to the non-controlling interest in Lucid represents the portion of earnings or loss attributable to the 49.9% economic interest held by Lucid non-controlling members whose allocation among the non-controlling members is not contingent upon services being provided. The portion of the 49.9% of Lucid earnings allocated among the non-controlling members of Lucid contingent on services provided is reported as a component of compensation expense and is included in the determination of Income (loss) from discontinued operations, net of tax in the condensed consolidated statements of operations (see Note 4). Net income or loss attributable to the non-controlling interests in Faros and V3 represents the portion of earnings or loss attributable to the 49.9% economic interests held by the non-controlling members of Faros (prior to the sale of Faros' operations in the second quarter of 2015) and V3. Net income or loss attributable to the non-controlling interests in other consolidated entities represents the portion of earnings or loss attributable to the economic interests held by the non-controlling members. Non-controlling interests in the condensed consolidated statements of financial condition represent the portion of equity attributable to the non-controlling interests of Holdings, Lucid, V3 and other consolidated entities. The allocation of equity to the non-controlling interests is based on the percentage owned by the non-controlling interest in the respective entity. The Company no longer holds its controlling interest in Faros as a result of the sale of Faros' operations in the second quarter of 2015. Investments where the Company is deemed to exercise significant influence, but no control, are accounted for using the equity method of accounting. The Company records its pro-rata share of earnings or losses each period and records any dividends as a reduction in the investment balance. The carrying value of these investments is included in Other assets in the condensed consolidated statements of financial condition and earnings or losses are included in Income or loss on equity method investments, net in the condensed consolidated statements of operations. For the Company's equity method investments classified as discontinued operations, the carrying value of the investments is included in assets held for sale on the condensed consolidated statements of financial condition and earnings or losses are included in the determination of Income or loss from discontinued operations, net of tax in the condensed consolidated statements of operations (see Note 6). Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions 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 as well as the reported amount of revenue and expenses during the year. Actual results could differ from those estimates and could have a material impact on the condensed consolidated financial statements. Reclassifications Certain reclassifications of prior period amounts related to the Company's retrospective adoption of Accounting Standards Update (“ASU”) No. 2015-03, Interest—Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs , have been made to conform to the current period's presentation in the condensed consolidated statements of financial condition (see Note 2). Interim Financial Statements The Company believes that the condensed consolidated interim financial statements reflect all adjustments of a normal recurring nature and disclosures that are necessary for a fair presentation of the results for the interim periods presented. The results of operations for the interim period are not necessarily indicative of the results of operations to be expected for the full year. The interim financial statements should be read in conjunction with the audited consolidated financial statements and related notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2015 . As permitted under Rule 10-01 of the Securities and Exchange Commission Regulation S-X, certain notes or other financial information are condensed or omitted in the condensed consolidated interim financial statements.

Significant Accounting Policies

Significant Accounting Policies and Estimates	6 Months Ended
	Jun. 30, 2016
Accounting Policies [Abstract]
Significant Accounting Policies and Estimates	Significant Accounting Policies and Estimates Our significant accounting policies are those that we believe are both important to the portrayal of our financial condition and results of operations. Management believes there have been no material changes to the significant accounting policies discussed in Note 2 of our Annual Report on Form 10-K for the fiscal year ended December 31, 2015 . Accounting Pronouncements Adopted in 2016 In April 2015, the FASB issued ASU No. 2015-03, Interest—Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs . ASU No. 2015-03 requires debt issuance costs to be presented in the balance sheet as a direct deduction from the corresponding debt liability rather than as an asset. The costs will continue to be amortized and reported as interest expense. The Company adopted ASU No. 2015-03 on January 1, 2016 on a retrospective basis. The adoption of ASU No. 2015-03 resulted in the reclassification of $2.9 million of unamortized debt issuance costs as of December 31, 2015 related to the Company's Senior convertible notes from Other assets, as previously reported, to the Senior convertible notes liability within the condensed consolidated statements of financial condition (see Note 13). The adoption of ASU No. 2015-03 also resulted in the reclassification of $0.5 million of unamortized debt issuance costs as of December 31, 2015 related to the Company's Credit Agreement from Other assets, as previously reported, to the Credit Agreement liability within the condensed consolidated statements of financial condition (see Note 12). Other than these reclassifications, the adoption of ASU No. 2015-03 did not have an impact on the Company's condensed consolidated financial statements. In February 2015, the FASB issued ASU No. 2015-02, Consolidation (Topic 810): Amendments to the Consolidation Analysis . ASU No. 2015-02 changes the analysis that a reporting entity must perform to determine whether it should consolidate certain types of legal entities. Specifically, ASU No. 2015-02 (i) modifies the evaluation of whether limited partnership and similar legal entities are VIEs, (ii) eliminates the presumption that a general partner should consolidate a limited partnership, (iii) affects the consolidation analysis of reporting entities that are involved with VIEs that have fee arrangements and related party relationships, and (iv) provides a scope exception from consolidation guidance for certain investment companies and similar entities. The Company adopted ASU No. 2015-02 on January 1, 2016 which did not have an impact on the Company's condensed consolidated financial statements. Recently Issued Accounting Pronouncements In January 2016, the FASB issued ASU No. 2016-01, Financial Instruments—Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities . This guidance in this update amends various aspects of the recognition, measurement, presentation, and disclosure for financial instruments. The guidance in this update is effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. Early adoption by public entities is permitted only for certain provisions. The adoption of this standard may result in a cumulative-effect adjustment to the consolidated statement of financial condition as of the beginning of the year of adoption. The Company expects to adopt this guidance beginning January 1, 2018 and is currently evaluating the impact that adoption of this standard will have on its consolidated financial statements. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) . ASU No. 2016-02 requires lessees to recognize, on the balance sheet, assets and liabilities for the rights and obligations created by leases classified as operating leases of greater than twelve months. The accounting by lessors will remain largely unchanged. The guidance in this update is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, with early adoption permitted. The new standard must be adopted using a modified retrospective approach, and provides for certain practical expedients. Transition will require application of the new guidance at the beginning of the earliest period presented. The Company expects to adopt this guidance beginning January 1, 2019 and is currently evaluating the impact that adoption of this standard will have on its consolidated financial statements. In March 2016, the FASB issued ASU No. 2016-06, Derivatives and Hedging (Topic 815): Contingent Put and Call Options in Debt Instruments . ASU No. 2016-06 clarifies the requirements for assessing whether contingent call (put) options that can accelerate the payment of principal on debt instruments are clearly and closely related to their debt hosts. An entity performing the assessment under the amendments in this update is required to assess the embedded call (put) options solely in accordance with the four-step decision sequence in ASC 815-15-25-42. The guidance in this update is effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. Early adoption is permitted. An entity should apply the amendments in this update on a modified retrospective basis to existing debt instruments as of the beginning of the fiscal year for which the amendments are effective. The Company expects to adopt this guidance beginning January 1, 2017 and is currently evaluating the impact that adoption of this standard will have on its consolidated financial statements. In March 2016, the FASB issued ASU No. 2016-07, Investments—Equity Method and Joint Ventures (Topic 323): Simplifying the Transition to the Equity Method of Accounting . ASU No. 2016-07 eliminates the requirement that an investor retrospectively apply equity method accounting when an investment that it had accounted for by another method initially qualifies for the equity method. The guidance requires that an equity method investor add the cost of acquiring the additional interest in the investee to the current basis of the investor’s previously held interest and adopt the equity method of accounting as of the date the investment becomes qualified for equity method accounting. The guidance in this update is effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. Earlier application is permitted. The Company expects to adopt this guidance beginning January 1, 2017 and does not currently expect it will have a material impact on its consolidated financial statements. In March 2016, the FASB issued ASU No. 2016-09, Compensation—Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting . ASU No. 2016-09 simplifies certain aspects related to the accounting for share-based payment transactions, including income tax consequences, statutory withholding requirements, forfeitures and classification on the statement of cash flows. The guidance in this update is effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. Early adoption is permitted. Certain of the amendments related to timing of the recognition of tax benefits and tax withholding requirements should be applied using a modified retrospective transition method. Amendments related to classification on the statement of cash flows should be applied retrospectively. All other provisions may be applied on a prospective or modified retrospective basis. The Company expects to adopt this guidance beginning January 1, 2017 and is currently evaluating the impact that adoption of this standard will have on its consolidated financial statements. In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) . The guidance in this update supersedes nearly all existing revenue recognition guidance under U.S. GAAP and creates a single, principle-based revenue recognition framework that is codified in a new FASB ASC Topic 606. The new revenue standard establishes principles for recognizing revenue to depict the transfer of goods or services to customers at an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods or services and allows for either the full retrospective or cumulative effect transition method of adoption. In August 2015, the FASB issued ASU No. 2015-14, Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date, which deferred the effective date of the new revenue standard by one year. The new effective date is for annual reporting periods beginning after December 15, 2017, and interim periods within those years. Early adoption is permitted for annual reporting periods beginning after December 15, 2016, including interim periods within that year. In March 2016, the FASB issued ASU No. 2016-08, Revenue from Contracts with Customers (Topic 606): Principal versus Agent Considerations (Reporting Revenue Gross versus Net) , an amendment to the guidance in ASU No. 2014-09 that clarifies how an entity should identify the unit of accounting for the principal versus agent evaluation and how it should apply the control principle to certain types of arrangements, such as service transactions. The amendments also reframe the indicators to focus on a principal rather than an agent and eliminated two of the indicators (“the entity’s consideration is in the form of a commission” and “the entity is not exposed to credit risk”). This amendment also clarifies that each indicator may be more or less relevant to the assessment depending on the terms and conditions of the contract. In April 2016, the FASB issued ASU No. 2016-10, Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing, an amendment to the guidance in ASU No. 2014-09 which clarifies the following two aspects of Topic 606: (a) identifying performance obligations and (b) the licensing implementation guidance. The amendments do not change the core principle of the guidance in Topic 606. In May 2016, the FASB issued ASU No. 2016-12, Revenue from Contracts with Customers (Topic 606): Narrow-Scope Improvements and Practical Expedients . ASU No. 2016-12, among other things: (1) clarifies the objective of the collectibility criterion for applying paragraph 606-10-25-7; (2) permits an entity to exclude amounts collected from customers for all sales (and other similar) taxes from the transaction price; (3) specifies that the measurement date for noncash consideration is contract inception; (4) provides a practical expedient that permits an entity to reflect the aggregate effect of all modifications that occur before the beginning of the earliest period presented when identifying the satisfied and unsatisfied performance obligations, determining the transaction price, and allocating the transaction price to the satisfied and unsatisfied performance obligations; (5) clarifies that a completed contract for purposes of transition is a contract for which all (or substantially all) of the revenue was recognized under legacy GAAP before the date of initial application, and (6) clarifies that an entity that retrospectively applies the guidance in Topic 606 to each prior reporting period is not required to disclose the effect of the accounting change for the period of adoption. The amendments do not change the core principle of the guidance in Topic 606. The effective date and transition requirements for the Topic 606 amendments are the same as the effective date and transition requirements in Topic 606. The updated standard is effective for the Company's first quarter of 2018. The Company is currently evaluating the impact of this guidance on its consolidated financial statements and has not yet selected a transition method.

Non-Controlling Interests

Non-Controlling Interests	6 Months Ended
	Jun. 30, 2016
Noncontrolling Interest [Abstract]
Non-Controlling Interests	Non-Controlling Interests Holdings The Corporation consolidates the financial results of Holdings and records a non-controlling interest for the economic interest in Holdings not owned by the Corporation. Pursuant to an agreement between the Corporation and Holdings, whenever the Corporation cancels, issues or repurchases shares of its Class A common stock, Holdings enters into an equivalent Holdings Unit transaction with the Corporation so that at all times the number of shares of Class A common stock is equal to the Corporation's membership units in Holdings. In addition, whenever the owners of Holdings prior to the initial public offering ("Existing Unit Holders") (other than the Corporation) exchange their Holdings Units for shares of the Corporation’s Class A common stock, Holdings is required to transfer an equal amount of Holdings Units to the Corporation. There were no changes in the non-controlling and the Corporation's interests in Holdings for the six months ended June 30, 2016 : Controlling Non- Total FXCM Inc. Non- Total Balance as of January 1, 2016 5,602,534 2,637,089 8,239,623 67.9 % 32.1 % 100 % Holdings Units acquired by FXCM Inc. related to exchanges of Holdings Units for shares of Class A common stock — — — — % — % — % Balance as of June 30, 2016 5,602,534 2,637,089 8,239,623 67.9 % 32.1 % 100.0 % Lucid, V3 and Other Non-Controlling Interests The Company owns controlling interests in Lucid, V3 and other entities and consolidates the financial results of these entities whereby it records a non-controlling interest for the economic interests not owned by the Company. Lucid and V3 are classified as discontinued operations and the assets and liabilities of Lucid and V3 are classified as held for sale on the condensed consolidated statements of financial condition (see Note 4). The Company no longer holds a controlling interest in Faros as a result of the sale of Faros' operations in the second quarter of 2015.

Discontinued Operations

Discontinued Operations	6 Months Ended
	Jun. 30, 2016
Discontinued Operations and Disposal Groups [Abstract]
Discontinued Operations	Discontinued Operations As a result of the losses incurred by the Company on January 15, 2015 related to the Swiss National Bank ("SNB") releasing the peg of the Swiss Franc to the Euro and the subsequent Leucadia financing arrangement entered into by the Company on January 16, 2015, the Company committed to a plan during the first quarter of 2015 to sell its interests in certain retail and institutional businesses in order to pay down the Leucadia debt. The retail businesses are HK, FXCMJ and the equity trading business of FSL. The institutional businesses are Faros, Lucid, V3 and the Company's equity interest in FastMatch. In April 2015, the Company completed the sales of FXCMJ and Faros. In September 2015, the Company completed the sale of HK. In December 2015, the Company completed the sale of the equity trading business of FSL. The Company remains committed to a plan to sell Lucid, V3 and its equity interest in FastMatch and continues to actively market these businesses. The Company considered the guidance in ASC 205-20 in evaluating the accounting and presentation in the condensed consolidated financial statements of the businesses that have been sold during the period and the remaining businesses to be sold. The operations and cash flows of these businesses are clearly distinguishable and, accordingly, have been determined to represent a group of components as defined in the guidance. It was further determined that the remaining businesses to be sold continue to meet the criteria for classification as held for sale as of June 30, 2016 . Accordingly, the assets and liabilities of these businesses were classified as assets and liabilities held for sale on the condensed consolidated statements of financial condition as of June 30, 2016 and December 31, 2015 . In accordance with ASC 205-20, to qualify for reporting as a discontinued operation, components that are disposed of or classified as held for sale must represent a strategic shift that has or will have a major effect on the Company's operations and financial results. The Company believes that the dispositions of these businesses represent a strategic shift from the Company’s diversification strategy undertaken for the past several years and concluded that the businesses to be disposed of qualify for reporting as discontinued operations. Accordingly, the results of operations of these businesses are reported in Income (loss) from discontinued operations, net of tax in the condensed consolidated statements of operations for the three and six months ended June 30, 2016 and 2015 . Completed dispositions In April 2015, the Company completed the sale of FXCMJ to Rakuten Securities, Inc. ("Rakuten Sec") for a cash purchase price of $62.2 million . The Company recognized a net gain of approximately $2.0 million related to the sale, which included a reversal of $23.4 million of foreign currency translation loss out of accumulated other comprehensive income. The net gain was recorded in earnings as a component of Income (loss) from discontinued operations, net of tax during the second quarter of 2015. In connection with the sale of FXCMJ, the Company agreed to provide certain transitional services, including use of the Company’s trading platform and data services, for no additional consideration for a period of nine months following the date of sale. The Company estimated the value of these services to be approximately $2.1 million and accordingly allocated $2.1 million of proceeds received as deferred income. The deferred income was amortized into other income over the nine-month period ending December 31, 2015 . The terms of the services agreement provide for the Company to receive a monthly fee for these services beginning January 1, 2016 for an expected period of ten months ending on October 31, 2016. The Company recorded other income for these transitional services of $0.5 million and $1.2 million for the three and six months ended June 30, 2016 , respectively. In April 2015, Faros completed the sale of its operations to Jefferies Group LLC. Consideration will be determined quarterly pursuant to an earn-out formula based on Faros' results beginning on the closing date and ending on November 30, 2017. Any consideration received will be divided among the Company and the non-controlling members of Faros based on a formula in the sales agreement. No consideration was received during the three and six months ended June 30, 2016 and 2015 . In September 2015, the Company completed the sale of HK to Rakuten Sec for a cash purchase price of $37.9 million . The Company recognized a net gain related to the sale of approximately $12.4 million . The net gain was recorded in earnings as a component of Income (loss) from discontinued operations, net of tax during the third quarter of 2015. In connection with the sale of HK, the Company agreed to provide certain transitional services, including use of the Company's trading platform, data services and professional support, for no additional consideration for a period of nine months following the date of sale. The Company estimated the value of these services to be approximately $1.0 million and accordingly allocated $1.0 million of proceeds received as deferred income. The deferred income was amortized into other income over the nine-month period following the date of sale. The Company recorded $0.3 million and $0.6 million of other income for these transitional services for the three and six months ended June 30, 2016 , respectively. Beginning nine months after the date of sale, the Company will receive a monthly fee for such services for a minimum period of nine months. In December 2015, the Company completed the sale of the equity trading business of FSL to AS Expobank for a cash purchase price of $2.3 million . The Company recognized a net loss of approximately $7.1 million related to the sale, which included a reversal of $1.5 million of foreign currency translation loss out of accumulated other comprehensive income. The net loss was recorded in earnings as a component of Income (loss) from discontinued operations, net of tax for the fourth quarter of 2015. In connection with the sale of the equity trading business of FSL, the Company agreed to provide certain transitional services, primarily professional support, for no additional consideration for a period of twelve months following the date of sale. The Company estimated the value of these services to be approximately $0.5 million and accordingly allocated $0.5 million of proceeds received as deferred income. The deferred income will be amortized into other income over the twelve-month period following the date of sale. The Company recorded $0.1 million and $0.3 million of other income for these transitional services for the three and six months ended June 30, 2016 , respectively. The following table presents the major classes of line items constituting the pretax and after-tax profit or loss of discontinued operations for the three and six months ended June 30, 2016 and 2015 , with amounts in thousands: Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 Revenues Trading revenue $ 7,468 $ 20,486 $ 13,804 $ 46,768 Interest income 10 31 139 218 Brokerage interest expense — (36 ) — (71 ) Net interest revenue 10 (5 ) 139 147 Other income 24 977 24 3,372 Total net revenues 7,502 21,458 13,967 50,287 Operating Expenses Compensation and benefits 472 3,766 513 10,801 Allocation of net income to Lucid members for services provided 1,360 1,981 2,561 4,667 Total compensation and benefits 1,832 5,747 3,074 15,468 Referring broker fees — — — 208 Advertising and marketing — 209 — 721 Communication and technology 1,426 2,180 2,923 4,467 Trading costs, prime brokerage and clearing fees 3,099 4,790 6,709 10,538 General and administrative 1,117 1,242 1,622 3,237 Bad debt expense — — — 8,408 Depreciation and amortization — — — 12,359 Goodwill impairment loss — — — 54,865 Total operating expenses 7,474 14,168 14,328 110,271 Operating income (loss) 28 7,290 (361 ) (59,984 ) Other (Expense) Income (Loss) income on equity method investments, net (60 ) (576 ) 93 (501 ) Gain on disposition of equity method investment (see Note 6) — — 679 — (Loss) income from discontinued operations before income taxes (32 ) 6,714 411 (60,485 ) Gain on completed dispositions — 1,978 — 1,978 Loss on classification as held for sale before income taxes (486 ) (2,300 ) (31,997 ) (28,799 ) Total (loss) income from discontinued operations before income taxes * (518 ) 6,392 (31,586 ) (87,306 ) Income tax provision — 727 — 5,627 (Loss) income from discontinued operations, net of tax $ (518 ) $ 5,665 $ (31,586 ) $ (92,933 ) * Total (loss) income from discontinued operations before income taxes attributable to FXCM Inc. was $(0.1) million and $(11.6) million for the three and six months ended June 30, 2016 , respectively, and $1.6 million and $(28.9) million for the three and six months ended June 30, 2015 , respectively. The following is a summary of the carrying amounts of the assets and liabilities included as part of discontinued operations as of June 30, 2016 and December 31, 2015 , with amounts in thousands: As of June 30, 2016 December 31, 2015 Assets Cash and cash equivalents $ 13,471 $ 10,786 Due from brokers (1) 18,550 22,234 Accounts receivable, net 113 178 Office, communication and computer equipment, net 1,274 1,154 Goodwill 223,613 223,613 Other intangible assets, net 27,269 27,269 Other assets (2) (3) 14,097 15,363 Loss recognized on classification as held for sale (98,657 ) (66,660 ) Total assets classified as held for sale on the condensed consolidated statements of financial condition $ 199,730 $ 233,937 Liabilities Accounts payable and accrued expenses (4) $ 9,505 $ 10,838 Due to brokers (1) 256 — Securities sold, not yet purchased 3,896 3,624 Other liabilities 33 48 Total liabilities classified as held for sale on the condensed consolidated statements of financial condition $ 13,690 $ 14,510 ____________________________________ (1) Includes as of June 30, 2016 and December 31, 2015 : a) derivative assets, net of $2.8 million and $0.9 million , respectively; b) Unsettled spot FX net asset of $0.1 million and $0.3 million , respectively; c) Unsettled common stock of $3.0 million and $3.0 million , respectively; and d) Excess cash collateral of $12.6 million and $18.0 million , respectively. (2) Includes the Company's exchange memberships, which represent ownership interests and shares owned in CME Group Inc. and provide the Company with the right to conduct business on the exchange. The exchange memberships are recorded at cost or, if an other-than-temporary impairment in value has occurred, at a value that reflects management's estimate of the impairment. The Company had previously owned shares in the Intercontinental Exchange which were sold in April 2015. The Company recognized a gain of $0.1 million related to the sale which was recorded in earnings as a component of Income (loss) from discontinued operations, net of tax during the second quarter of 2015. In the fourth quarter of 2015, the Company acquired additional ownership interests and shares in CME Group Inc. from one of the non-controlling members of Lucid which were recorded at a total cost of $3.7 million . There were no exchange membership impairments as of June 30, 2016 or December 31, 2015 . As of both June 30, 2016 and December 31, 2015 , the carrying value of ownership interests was $4.6 million and the carrying value of shares owned was $4.8 million . (3) Includes the carrying value of the Company's equity interest in FastMatch of $4.2 million as of both June 30, 2016 and December 31, 2015 . The carrying value of the Company's previously-held equity interest in the V3-related LLC of $1.5 million is included in the balance as of December 31, 2015 (see Note 6). (4) Includes as of June 30, 2016 and December 31, 2015 amounts due related to the allocation of income to Lucid non-controlling members for services provided of $5.7 million and $6.5 million , respectively.

Notes Receivable

Notes Receivable	6 Months Ended
	Jun. 30, 2016
Receivables [Abstract]
Notes Receivable	Notes Receivable In January 2014, in connection with the formation of V3 by the Company and the non-controlling members of Lucid, the non-controlling members of Lucid borrowed approximately $7.9 million from the Company to assist with funding their portion of the capital contribution. The amount borrowed is due in 2017 and bears interest at the rate of 2% per annum. During the three months ended June 30, 2016 , management determined that the non-controlling members of Lucid will not be required to repay the notes receivable and the debt will be forgiven. Accordingly, the Company recorded a provision for the debt forgiveness in the amount of $8.2 million for the principal amount thereof plus accrued interest, which is included in General and administrative expense in the condensed consolidated statements of operations.

Equity Method Investments

Equity Method Investments	6 Months Ended
	Jun. 30, 2016
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments	Equity Method Investments The Company has a 22.1% equity interest in a developer of FX trading software which is accounted for using the equity method. The carrying value of the Company's equity interest in the FX trading software developer of $2.3 million and $2.6 million as of June 30, 2016 and December 31, 2015 , respectively, is included as a component of Other assets in the condensed consolidated statements of financial condition. The Company's share of the loss of the FX trading software developer was $0.1 million and $0.3 million for the three and six months ended June 30, 2016 , respectively, and $37 thousand and $0.2 million for the three and six months ended June 30, 2015 , respectively, and is included in Loss on equity method investments, net in the condensed consolidated statements of operations. The Company has a 35.1% non-controlling equity interest in FastMatch, an electronic communication network for foreign exchange trading, and exerts significant influence. The investment is accounted for using the equity method. As discussed in Note 4, the Company's equity interest in FastMatch is classified as a discontinued operation. In conjunction with the V3 acquisition in January 2014, the Company acquired a 66.3% non-controlling interest in a limited liability company ("V3-related LLC") that held a 17.26% interest in a firm that delivers investment information to investment professionals. Until December 31, 2015 , the other members of the V3-related LLC had not consented to the transfer of the 66.3% non-controlling interest to the Company and the investment had been accounted for using the equity method. On December 31, 2015 , the other members of the V3-related LLC approved a resolution to transfer the 66.3% non-controlling interest to the Company and, in a related transaction, to distribute the assets held by the V3-related LLC to its members, including the Company, and subsequently liquidate the V3-related LLC. These transactions were completed during the first quarter of 2016 and resulted in the Company's acquisition of an equity interest in the firm described above which is accounted for using the cost method. The carrying value of the investment was $1.1 million as of June 30, 2016 and is included as a component of Other assets in the condensed consolidated statements of financial condition. As discussed in Note 4, V3, including the equity interest previously held in the V3-related LLC, is classified as a discontinued operation. Income (loss) from discontinued operations, net of tax for the six months ended June 30, 2016 includes a gain of $0.7 million related to the disposition of the V3-related LLC in the first quarter of 2016. The carrying values of the Company's equity interests in FastMatch and the V3-related LLC (prior to its disposition) are included in assets held for sale on the condensed consolidated statements of financial condition. As of June 30, 2016 and December 31, 2015 , the carrying values of the Company's equity method investments included in assets held for sale were $4.2 million and $5.7 million , respectively. The Company's share of the income or loss of FastMatch and the V3-related LLC (prior to its disposition) is included in Income (loss) from discontinued operations, net of tax in the condensed consolidated statements of operations. Total (loss) income on equity method investments included in Income (loss) from discontinued operations, net of tax was $(0.1) million and $0.1 million for the three and six months ended June 30, 2016 , respectively, and $(0.6) million and $(0.5) million for the three and six months ended June 30, 2015 , respectively. Dividend distributions received by the Company from its equity method investments during the three and six months ended June 30, 2016 were not material. The Company did not receive any dividend distributions from its equity method investments during the three and six months ended June 30, 2015 .

Goodwill

Goodwill	6 Months Ended
	Jun. 30, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	Goodwill During the first quarter of 2015, the Company performed an interim impairment assessment of goodwill due to the events of January 15, 2015 and the Company's plan to sell certain businesses. This assessment resulted in the Company recording goodwill impairment losses of $9.5 million from continuing operations during the first quarter of 2015 primarily due to a decline in the implied fair value of certain institutional businesses subsequent to January 15, 2015. The impairment loss is presented as a separate line item in the condensed consolidated statements of operations and included as a component of Loss from continuing operations for the six months ended June 30, 2015 . During the fourth quarter of 2015, the Company completed its annual testing for impairment of goodwill and, based on the evaluation performed, concluded that goodwill was not impaired as of October 1, 2015. During the six months ended June 30, 2016 , no triggering events have occurred that would indicate that it is more likely than not that goodwill is impaired. Changes in goodwill for the six months ended June 30, 2016 are presented in the following table and reflect the Company's single operating segment, with amounts in thousands: Balance as of January 1, 2016 $ 28,080 Foreign currency translation adjustments (2,717 ) Balance as of June 30, 2016 $ 25,363

Other Intangible Assets, net

Other Intangible Assets, net	6 Months Ended
	Jun. 30, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Other Intangible Assets, net	Other Intangible Assets, net The Company’s intangible assets consisted of the following as of June 30, 2016 and December 31, 2015 , with amounts in thousands: June 30, 2016 December 31, 2015 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Finite-lived intangible assets Customer relationships $ 35,460 $ (24,259 ) $ 11,201 $ 35,460 $ (21,223 ) $ 14,237 Foreign currency translation adjustment (3,630 ) 1,499 (2,131 ) (1,910 ) 855 (1,055 ) Total finite-lived intangible assets 31,830 (22,760 ) 9,070 33,550 (20,368 ) 13,182 Indefinite-lived intangible assets License 600 — 600 600 — 600 Total Other intangible assets, net $ 32,430 $ (22,760 ) $ 9,670 $ 34,150 $ (20,368 ) $ 13,782 In the second quarter of 2015, the Company acquired certain margin FX trading accounts from Citibank, N.A. and Citibank International Limited. The asset purchase agreement provides for cash consideration payable quarterly based on a pre-determined formula until total payments reach $6.0 million ("Threshold"). Additional cash consideration ("Contingent Consideration") is payable if total payments meet the Threshold before the expiration of an initial 30 -month period. The acquired accounts represent customer relationships and are recorded as intangible assets at an initial cost of $6.0 million . Transaction costs incurred were not material. The Contingent Consideration is recognizable when it becomes payable, i.e., when it is probable and reasonably estimable, consistent with the guidance in ASC 450-20, Loss Contingencies , and, to the extent any amounts are recorded, included in the cost basis of the acquired intangible assets. There was no Contingent Consideration recorded as of June 30, 2016 . The customer relationships are amortized on a straight-line basis over a weighted-average amortization period of three years. During the first quarter of 2015, the Company performed an interim impairment evaluation of intangible assets due to the events of January 15, 2015 and the Company's plans to sell certain businesses. This evaluation resulted in the Company recording impairment losses of $5.4 million due to a decline in the implied fair value of certain institutional businesses subsequent to the events of January 15, 2015. The impairment charge is included as a component of amortization expense within discontinued operations for the six months ended June 30, 2015 . No impairment of intangible assets has been identified as of June 30, 2016 . Intangible assets related to businesses to be disposed of are included as a component of assets held for sale on the condensed consolidated statements of financial condition and are not included in the table above. Amortization related to these intangible assets ceased as of the date they were determined to be held for sale. Amortization expense from continuing operations included in the condensed consolidated statements of operations was $2.0 million and $3.9 million for the three and six months ended June 30, 2016 , respectively, and $1.5 million and $3.0 million for the three and six months ended June 30, 2015 , respectively. Amortization expense related to intangible assets to be disposed of is included in Income (loss) from discontinued operations, net of tax in the condensed consolidated statements of operations. Estimated future amortization expense for intangible assets outstanding as of June 30, 2016 is as follows, with amounts in thousands: Year Ending December 31, Remainder of 2016 $ 3,273 2017 4,039 2018 1,433 2019 325 2020 — Thereafter — $ 9,070

Earnings per Share

Earnings per Share	6 Months Ended
	Jun. 30, 2016
Earnings Per Share [Abstract]
Earnings per Share	Earnings per Share On October 1, 2015, the Company effected a one-for-ten reverse stock split of the Corporation's issued and outstanding Class A common stock (see Note 1). As a result, all references to number of Class A common shares, number of Holdings Units, price per share and weighted average shares of Class A common stock have been adjusted to reflect the one-for-ten reverse stock split on a retroactive basis for the prior periods presented, unless otherwise noted. Basic earnings per share (“EPS”) measures the performance of an entity over the reporting period. Diluted EPS measures the performance of an entity over the reporting period while giving effect to all potentially dilutive instruments that were outstanding during the period. The Company uses the treasury stock method in accordance with ASC 260, Earnings per Share (“ASC 260”), to determine diluted EPS. Due to the Corporation's loss from continuing operations for the three and six months ended June 30, 2015 , any potential common shares were not included in the computation of diluted EPS as they would have had an antidilutive effect since the shares would decrease the loss per share. As a result, basic and diluted net loss per share of Class A common stock are equal for these periods. In accordance with ASC 260, all outstanding unvested share-based payments that contain rights to non-forfeitable dividends participate in the undistributed earnings with the common stockholders and are therefore participating securities. The Company's unvested restricted stock units ("RSUs") do not contain rights to dividends or dividend equivalents. As a result, unvested RSUs are not considered participating securities and are therefore not required to be included in computing basic EPS under the two-class method. The shares of Class B common stock do not share in the earnings of the Company and are not considered participating securities. Accordingly, basic and diluted net earnings per share of Class B common stock have not been presented. In April 2015, the Company entered into an option agreement with a customer as part of a negative equity balance settlement and issued an immediately vested, two -year option to purchase 56,934 shares of Class A common stock of FXCM Inc. The option has a strike price of $22.50 . For the three and six months ended June 30, 2016 and 2015 , the stock option was not included in the computation of diluted EPS because it was antidilutive under the treasury method. In computing diluted EPS, outstanding stock options and other equity awards granted to certain employees, non-employees and independent directors in the aggregate of 741,578 for each of the three and six months ended June 30, 2016 and 777,148 for each of the three and six months ended June 30, 2015 were excluded because they were antidilutive under the treasury method. In June 2012, the Company issued 720,000 shares of the Corporation’s Class A common stock in connection with the acquisition of Lucid subject to the achievement of certain targets related to the financial performance of Lucid (the "Profit Targets") over a three -year term. In accordance with ASC 260, the anniversary shares are considered outstanding common shares and included in basic EPS as of the date that all necessary conditions to receiving the shares have been satisfied (that is, when issuance of the shares is no longer contingent) and there is no circumstance under which those shares would not be issued. The shares are considered for inclusion in diluted EPS prior to issuance if all necessary conditions have been satisfied by the end of the period. The Lucid sellers received 120,000 shares in June 2013 and 300,000 shares in June 2014. The Lucid sellers achieved the Profit Targets for the third anniversary shares during the quarter ended June 30, 2015 and received 300,000 shares in June 2015 which are included in the computation of basic EPS for the three and six months ended June 30, 2015. As described in Note 13, in June 2013 the Corporation issued $172.5 million principal amount of 2.25% senior convertible notes maturing on June 15, 2018 (the “Convertible Notes”). The Convertible Notes will be convertible at an initial conversion rate of 5.32992 shares of the Corporation's Class A common stock per $1,000 principal amount of the Convertible Notes, which is equivalent to an initial conversion price of approximately $187.62 . In accordance with ASC 260, the shares of the Corporation's Class A common stock issuable upon conversion of the Convertible Notes are included in the calculation of diluted EPS to the extent that the conversion value of the securities exceeds the principal amount. For diluted EPS purposes, the number of shares of the Corporation's Class A common stock that is necessary to settle such excess is considered issued. For the three and six months ended June 30, 2016 and 2015 , the conversion value did not exceed the principal amount and therefore the conversion effect was not included in the computation of diluted EPS because it was antidilutive under the treasury method. As described in Note 13, the Corporation also entered into a warrant transaction in June 2013 whereby the Corporation sold to the counterparties warrants to purchase shares of the Corporation's Class A common stock. For the three and six months ended June 30, 2016 and 2015 , the warrants were not included in the computation of diluted EPS because they were antidilutive under the treasury method. Additionally, the non-controlling members of Holdings have the right to exchange their Holdings Units for shares of the Corporation’s Class A common stock on a one -for-one basis at fair value, subject to customary conversion rate adjustments for stock splits, stock dividends and reclassifications. These shares were also excluded from the computation of diluted EPS because the shares have no impact, or would not be dilutive or antidilutive under the treasury method. There were no exchanges of Holdings Units during three and six months ended June 30, 2016 . During the three and six months ended June 30, 2015 , certain members of Holdings exchanged 0.1 million and 0.4 million , respectively, of their Holdings Units on a one -for-one basis, for shares of Class A common stock of the Corporation. The following is a reconciliation of the numerator and denominator used in the basic and diluted EPS calculations, with amounts in thousands except per share data: Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 Basic and diluted net income (loss) per share of Class A common stock: Numerator Income (loss) from continuing operations attributable to FXCM Inc. $ 60,495 $ (98,886 ) $ 121,765 $ (492,211 ) (Loss) income from discontinued operations attributable to FXCM Inc. (94 ) 3,075 (11,629 ) (30,417 ) Net income (loss) available to holders of Class A common stock 60,401 (95,811 ) 110,136 (522,628 ) Earnings allocated to participating securities — — — — Income (loss) available to common stockholders $ 60,401 $ (95,811 ) $ 110,136 $ (522,628 ) Denominator Weighted average shares of Class A common stock (1) 5,603 4,871 5,603 4,790 Add dilutive effect of the following: Stock options and RSUs (1),(2) — — — Convertible note hedges — — — Warrants — — — — Assumed conversion of Holdings Units for Class A common stock — — — — Dilutive weighted average shares of Class A common stock (1) 5,603 4,871 5,603 4,790 Net income (loss) per share of Class A common stock — Basic and Diluted (1) : Continuing operations $ 10.80 $ (20.30 ) $ 21.73 $ (102.76 ) Discontinued operations (0.02 ) 0.63 (2.08 ) (6.35 ) Net income (loss) per share of Class A common stock $ 10.78 $ (19.67 ) $ 19.65 $ (109.11 ) ____________________________________ (1) Prior periods are adjusted to reflect the impact of the one-for-ten reverse stock split that became effective on October 1, 2015. (2) No dilutive effect for the three and six months ended June 30, 2016 therefore zero incremental shares included for the period.

Related Party Transactions

Related Party Transactions	6 Months Ended
	Jun. 30, 2016
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions Amounts receivable from, and payable to, related parties are set forth below, with amounts in thousands: As of June 30, 2016 December 31, 2015 Receivables Advances to Holdings non-controlling members $ 505 $ 112 Accounts receivable — Lucid non-controlling members 15 15 Advances to employees 33 201 Notes receivable and interest — Lucid non-controlling members — 8,171 Total receivables from related parties $ 553 $ 8,499 Payables Employees $ 530 $ 1,104 Due to Lucid non-controlling members in connection with the allocation of income to Lucid non-controlling members for services provided 5,715 6,500 Tax receivable agreement — 145 Total payables to related parties $ 6,245 $ 7,749 The Company has advanced funds for withholding taxes to several non-controlling members of Holdings. The outstanding balances as of June 30, 2016 and December 31, 2015 , included in the table above, are included in Accounts receivable, net in the condensed consolidated statements of financial condition. Included in Current assets held for sale in the condensed consolidated statements of financial condition are advances to the Lucid non-controlling members. As of June 30, 2016 and December 31, 2015 , advances to the Lucid non-controlling members were not material. Prior to July 1, 2015, the Company received commission or mark-up income from institutional customers’ trades executed on FastMatch's electronic trading platform, an entity in which the Company owns a 35.1% equity interest (see Note 6). The Company paid a per trade fee to FastMatch for use of the platform. Effective July 1, 2015, institutional customers trading via the FastMatch platform became direct customers of FastMatch. Fees collected from customers for trades executed on the FastMatch platform were nil for both the three and six months ended June 30, 2016 and $3.4 million and $6.3 million for the three and six months ended June 30, 2015 , respectively, and are included in Trading revenue in the condensed consolidated statements of operations. Fees paid to FastMatch were nil for both the three and six months ended June 30, 2016 and $2.3 million and $4.3 million for the three and six months ended June 30, 2015 , respectively, and are reflected as a component of Communication and technology in the condensed consolidated statements of operations. The Company received nil and $0.1 million from FastMatch during the three and six months ended June 30, 2016 , respectively, for occupancy and operational costs, which is included in Other income in the condensed consolidated statements of operations. The Company has advanced funds to several employees. The outstanding balances as of June 30, 2016 and December 31, 2015 , included in the table above, are included in Accounts receivable, net in the condensed consolidated statements of financial condition. In January 2014, in connection with the formation of V3 by the Company and the non-controlling members of Lucid, the non-controlling members of Lucid borrowed approximately $7.9 million from the Company to assist with funding their portion of the capital contribution, which is included in Notes receivable in the condensed consolidated statements of financial condition. The amount borrowed is due in 2017 and bears interest at the rate of 2% per annum. During the three months ended June 30, 2016 , management determined that the non-controlling members of Lucid will not be required to repay the notes receivable and the debt will be forgiven. Accordingly, the Company recorded a provision for the debt forgiveness in the amount of $8.2 million for the principal amount thereof plus accrued interest, which is included in General and administrative expense in the condensed consolidated statements of operations. During the fourth quarter of 2015, Lucid acquired ownership interests and shares in CME Group Inc. from one of the non-controlling members of Lucid in a market-based transaction. The total carrying value of the ownership interests and shares was $3.7 million as of both June 30, 2016 and December 31, 2015 and are included in assets held for sale (see Note 4). Customer account liabilities in the condensed consolidated statements of financial condition include balances for employees. Amounts due related to the allocation of income to Lucid non-controlling members for services provided were $5.7 million and $6.5 million as of June 30, 2016 and December 31, 2015 , respectively, and are included in Current liabilities held for sale in the condensed consolidated statements of financial condition (see Note 4). Exchange Agreement The members of Holdings (other than the Corporation) entered into an exchange agreement under which they (or certain permitted transferees thereof) have the right (subject to the terms of the exchange agreement as described therein) to exchange their Holdings Units for shares of the Corporation’s Class A common stock on a one -for-one basis at fair value, subject to customary conversion rate adjustments for stock splits, stock dividends and reclassifications. During the six months ended June 30, 2016 and 2015, certain members of Holdings exchanged nil and 0.4 million , respectively of their Holdings Units, on a one -for-one basis, for shares of Class A common stock of the Corporation pursuant to the exchange agreement (after giving effect to the one-for-ten reverse stock split). Payments under Tax Receivable Agreement The Corporation entered into a tax receivable agreement with the members of Holdings (other than the Corporation) that will provide for the payment by the Corporation to Holdings’ members (other than the Corporation) as defined therein. Assuming sufficient taxable income is generated such that the Corporation fully realizes the tax benefits of the amortization specified in the tax receivable agreement, the aggregate payments currently estimated that would be due are $146.1 million and $146.8 million as of June 30, 2016 and December 31, 2015 , respectively. During the first quarter of 2015, the Corporation determined that it was not more likely than not that it would benefit from the tax deduction attributable to the tax basis step-up for which a portion of the benefit would be owed to the non-controlling members of Holdings under the tax receivable agreement and reduced the contingent liability under the tax receivable agreement to zero . As of June 30, 2016 , the Corporation continues to believe it will not benefit from the tax deduction and the contingent liability remains zero . During the six months ended June 30, 2016 and 2015 , payments of $0.2 million and $5.4 million , respectively, were made pursuant to the tax receivable agreement. The payment made in the first six months of 2016 relates to the 2014 tax return year. The Corporation currently does not expect to make a payment for the 2015 tax year. Other UK LTD was party to an arrangement with Global Finance Company (Cayman) Limited (“Global Finance”) and Master Capital Group, S.A.L. (“Master Capital”). An affiliated shareholder of the Company beneficially owns more than 90% of the equity of Global Finance and Master Capital. Pursuant to the arrangement, Global Finance and Master Capital were permitted to use the brand name “FXCM” and the Company's technology platform to act as its local presence in certain countries in the Middle East and North Africa (“MENA”). UK LTD collected and remitted to Global Finance and Master Capital fees and commissions charged by Global Finance and Master Capital to customers in MENA countries. Effective May 4, 2015, UK LTD terminated the arrangement with Global Finance and Master Capital. For the three and six months ended June 30, 2015, the fees and commissions related to the arrangement were nil and $0.2 million and are included in Referring broker fees in the condensed consolidated statements of operations.

Net Capital Requirements

Net Capital Requirements	6 Months Ended
	Jun. 30, 2016
Banking and Thrift [Abstract]
Net Capital Requirements	Net Capital Requirements The Company's regulated entities are subject to minimum capital requirements in their respective jurisdictions. The minimum capital requirements of the entities below may effectively restrict the payment of cash distributions by the subsidiaries. The tables below present the capital, as defined by the respective regulatory authority, the minimum capital requirement and the excess capital for the following regulated entities as of June 30, 2016 and December 31, 2015 , with amounts in millions: As of June 30, 2016 US UK LTD Australia Lucid LLP Capital $ 53.2 $ 84.9 $ 12.3 $ 11.7 Minimum capital requirement 34.2 21.3 0.7 4.8 Excess capital $ 19.0 $ 63.6 $ 11.6 $ 6.9 As of December 31, 2015 US UK LTD Australia Lucid LLP Capital $ 43.6 $ 76.3 $ 12.0 $ 10.9 Minimum capital requirement 28.3 27.6 0.7 4.0 Excess capital $ 15.3 $ 48.7 $ 11.3 $ 6.9

Leucadia Transaction

Leucadia Transaction	6 Months Ended
	Jun. 30, 2016
Extraordinary and Unusual Items [Abstract]
Leucadia Transaction	Leucadia Transaction On January 15, 2015, the Company's customers suffered significant losses and generated negative equity balances ("debit balances") owed to it of approximately $275.1 million . This was due to the unprecedented volatility in the EUR/CHF currency pair after the SNB discontinued its currency floor of 1.2 CHF per EUR on that date. When a customer entered a EUR/CHF trade with the Company, the Company executed an identical trade with a FX market maker. During the historic move liquidity became extremely scarce and shallow, which affected execution prices. This liquidity issue resulted in some customers having losses in excess of their account balance. While customers could not cover their margin call with the Company, the Company still had to cover the same margin call with the FX market maker. When a customer profits in the trade, the Company gives the profits to the customer, however, when the customer is not profitable on that trade the Company is obligated to pay the FX market maker regardless of whether the Company collects the funds from its customers. These debit balances resulted in a temporary breach of certain regulatory capital requirements. On January 16, 2015, Holdings and Newco entered into a credit agreement (the “Credit Agreement”) with Leucadia, as administrative agent and lender, and a related financing fee agreement (the “Fee Letter”). The financing provided to the Company pursuant to these agreements, which is described below, enabled the Company to maintain compliance with regulatory capital requirements and continue operations. On January 16, 2015, the Corporation, Holdings, Newco and Leucadia also entered into an agreement (the “Letter Agreement”) that set the terms and conditions upon which the Corporation, Holdings and Newco will pay in cash to Leucadia and its assignees a percentage of the proceeds received in connection with certain transactions. In connection with these financing transactions, Holdings formed Newco and contributed all of the equity interests owned by Holdings in its subsidiaries to Newco. The Credit Agreement and the Letter Agreement were subsequently amended on January 24, 2015. The Company recorded a recovery of bad debt expense of $0.1 million from continuing operations in the condensed consolidated statements of operations for the three and six months ended June 30, 2016 related to the events of January 15, 2015. There was zero bad debt expense from discontinued operations in the condensed consolidated statements of operations for the three and six months ended June 30, 2016 related to the events of January 15, 2015. Bad debt expense from continuing operations in the condensed consolidated statements of operations for the three and six months ended June 30, 2015 includes net expense of $0.4 million and $257.3 million , respectively, related to the debit balances. Bad debt expense for the three months ended June 30, 2015 includes $0.1 million of reversal of recoveries returned to clients, as well as $0.3 million reversal of recovery as payment for an option agreement entered into with a customer as part of a negative equity balance settlement (see Note 17). Bad debt expense from continuing operations for the six months ended June 30, 2015 reflects net recoveries of $9.3 million . Bad debt expense included in Income (loss) from discontinued operations, net of tax in the condensed consolidated statements of operations for the three and six months ended June 30, 2015 includes net expense of nil and $8.4 million related to the debit balances, which reflects recoveries during these periods of nil and $0.1 million , respectively. Memorandum of Understanding with Leucadia On March 10, 2016 the Company entered into a nonbinding memorandum of understanding (“MOU”) with Leucadia to amend the terms of the Credit Agreement and the Letter Agreement between the Corporation, Holdings, Newco and Leucadia. The amendments to the Credit Agreement will extend the maturity date of the term loan by one year to January 2018. Additionally, the Company will have the right to defer any three of the remaining interest payments by paying interest in kind. Until the loan and interest under the amended Credit Agreement are fully repaid, all distributions and sales proceeds will continue to be used solely to repay the loan plus interest. The MOU also provides for the termination of the Letter Agreement and its terms shifted to Newco’s LLC agreement. The existing Newco LLC agreement will be amended, Newco will be renamed FXCM Group LLC (“FXCM Group”) and Leucadia will own a 49.9% common membership interest in FXCM Group. Holdings will own a 50.1% common membership interest in FXCM Group. Distributions from FXCM Group will not be permitted until the principal and interest due under the amended Credit Agreement is repaid. FXCM Group will be governed by an eight -member board, comprising three directors appointed by Leucadia, three directors appointed by the Company and two independent directors, one each to be nominated by Leucadia and the Company. After January 2018, Leucadia and the Company will each have the right to begin a process that could unwind the partnership, potentially resulting in a sale process for FXCM Group. A long-term incentive program with a five -year vesting period will be put into place to retain and incentivize senior management of FXCM to maximize cash flow generation and growth of the business. The long-term incentive plan will operate only after the principal and interest under the amended Credit Agreement is repaid and will equal the following: • 10.0% of all distributions or sales proceeds from FXCM Group up to $350 million ; • 12.0% of all distributions or sales proceeds from FXCM Group from $350 million to $850 million ; and • 14.0% of all distributions or sales proceeds from FXCM Group above $850 million . Long-term incentive plan participants will receive their share of any distributions or sales proceeds while unvested. Leucadia will own a non-voting preferred class of membership interest that, when added to its 49.9% common membership interest, will result in the following distribution of proceeds from FXCM Group: Aggregate amount of proceeds Original Waterfall Revised Waterfall Amounts due under the Credit Agreement 100% Leucadia 100% Leucadia Next $350 million 50% Leucadia / 50% FXCM 45% Leucadia / 45% FXCM / 10.0% FXCM management Next $500 million 90% Leucadia / 10% FXCM 79.2% Leucadia / 8.8% FXCM / 12.0% FXCM management All aggregate amounts thereafter 60% Leucadia / 40% FXCM 51.6% Leucadia / 34.4% FXCM / 14.0% FXCM management The nonbinding MOU with Leucadia remains subject to the execution of definitive agreements and Board approval. The Company expects the amendments to the Credit Agreement and the Letter Agreement to be completed by the end of the third quarter of 2016. The Company is currently evaluating the accounting impact that the amendments will have on its consolidated financial statements, which is expected to be material. An estimate of the quantitative impact to the consolidated financial statements cannot be made at this time. Amended and Restated Credit Agreement The Amended and Restated Credit Agreement (“Credit Agreement”), dated January 24, 2015, provides for a $300.0 million term loan made by Leucadia to Holdings and Newco. The net proceeds of the loan ( $279.0 million ) were used to replace capital in the Company’s regulated entities to cover negative client balances and pay down outstanding revolving debt. Holdings’ prior revolving credit agreement with Bank of America, N.A. was repaid in full and terminated effective January 20, 2015. As noted above, the Credit Agreement was initially entered into on January 16, 2015 and subsequently amended on January 24, 2015. The purpose of the amendment was to finalize certain terms of the Credit Agreement and the terms of the amended agreement and the initial agreement were not substantially different. Accordingly, the amendment was accounted for as a modification pursuant to ASC 470, Debt ("ASC 470"). The loan matures on January 16, 2017. The obligations under the Credit Agreement are guaranteed by certain wholly-owned unregulated domestic subsidiaries of the Company and are secured by substantially all of the assets of Holdings and certain subsidiaries of the Corporation, including a pledge of all of the equity interests in certain of Holdings’ domestic subsidiaries and 65% of the voting equity interests in certain of its foreign subsidiaries. The loan has an initial interest rate of 10% per annum, increasing by 1.5% per annum each quarter for so long as it is outstanding, but in no event exceeding 20.5% per annum (before giving effect to any applicable default rate). Under certain circumstances, a default interest rate will apply on all obligations during the event of default at a per annum rate equal to 2% above the applicable interest rate. The Credit Agreement requires the payment of a deferred financing fee in an amount equal to $10.0 million , with an additional fee of up to $30.0 million payable in the event the aggregate principal amount of the term loan outstanding on April 16, 2015 was greater than $250.0 million or the deferred financing fee of $10.0 million (plus interest) had not been paid on or before such date. Prior to April 16, 2015, the Company repaid approximately $56.5 million which reduced the aggregate principal to $243.5 million on April 16, 2015. Additionally, the Company paid the $10.0 million deferred financing fee prior to April 16, 2015. Accordingly, the Company was not obligated to pay the additional $30.0 million fee. As of June 30, 2016 , the Company has paid $117.5 million of principal, of which $10.0 million was applied to the deferred financing fee. The Credit Agreement is subject to various conditions and terms such as requiring mandatory prepayments, including from proceeds of dispositions, condemnation and insurance proceeds, debt issuances, equity issuances, and capital contributions. The Credit Agreement requires monthly payments of the term loan from proceeds received during the immediately preceding calendar month from accounts receivable related to customer debit balances. The loan may be voluntarily prepaid without penalty. The Credit Agreement includes a variety of restrictive covenants, including, but not limited to: limitations on the ability to merge, dissolve, liquidate, consolidate or sell, lease or otherwise transfer all or substantially all assets; limitations on the incurrence of liens; limitations on the incurrence of debt by subsidiaries; limitations on the ability of Newco to make distributions in respect of its equity interests including distributions to pay interest due on the Company’s convertible notes and limitations on transactions with affiliates, without the prior consent of the lender. The Credit Agreement also provides for events of default, including, among others: non-payments of principal and interest; breach of representations and warranties; failure to maintain compliance with the other covenants contained in the Credit Agreement; default under other material debt; the existence of bankruptcy or insolvency proceedings; insolvency; and a change of control. Amended and Restated Letter Agreement The Amended and Restated Letter Agreement (“Letter Agreement”), dated January 24, 2015, provides, among other things, that Holdings and Newco will pay in cash to Leucadia and its assignees a percentage of the net proceeds received in connection with certain transactions, including sales of assets (subject to certain limited exceptions), dividends or distributions, the sale or indirect sale of Newco (whether by merger, stock purchase, sale of all or substantially all of Newco’s assets or otherwise), the issuance of any debt (subject to certain limited exceptions) or equity securities, and other specified non-ordinary course events, such as certain tax refunds and litigation proceeds. As noted above, the Letter Agreement was initially entered into on January 16, 2015 and subsequently amended on January 24, 2015. The purpose of the amendment was to finalize certain terms of the Letter Agreement and the terms of the amended agreement and the initial agreement were not substantially different. Since the amended terms were not considered substantive, the fair value of the Letter Agreement was not impacted and the amendment was accounted for as a modification. The Letter Agreement allocates net proceeds as follows: Aggregate amount of proceeds Leucadia FXCM Holdings Amounts due under Leucadia term loan, including fees 100% 0% Next $350 million 50% 50% Next $500 million * 90% 10% All aggregate amounts thereafter 60% 40% * Per the Letter Agreement, this amount was initially set at a range of $500 million to $680 million . As a result of the prepayments made by the Company through April 16, 2015, this amount is $500 million . In addition to the payments above, Leucadia and its assignees are entitled to tax distributions in the event that they are allocated income by Newco as a result of their rights under the Letter Agreement. If any such tax distributions are made, the amounts of such distributions reduce the payments to be made to Leucadia and its assignees pursuant to the allocation methodology described above (other than with respect to the repayment of the loan). In addition, the Letter Agreement provides that beginning on January 16, 2018, upon the request of Leucadia or its assignees, the Corporation, Holdings and Newco will cause the sale of Holdings, Newco and/or any of their respective subsidiaries’ assets or equity interests for cash at the highest reasonably available price. Upon the occurrence of such event, Newco will pay Leucadia and its assignees in accordance with the methodology described above. In the event of a change of control, at the request of Leucadia or its assignees, Holdings and Newco will be required to pay Leucadia and its assignees in cash a one-time payment equal to the fair market value of their contractual rights pursuant to the Letter Agreement. For this purpose, change of control is generally defined as an event or series or events by which (i) a person or group acquires 40% or more of the voting interests of the Corporation, (ii) the Corporation and the existing members of Holdings cease to own 90% of the equity interests of Holdings, (iii) the Corporation ceases to be the sole managing member of Holdings, (iv) Holdings ceases to be the sole member of Newco or (v) subject to certain exceptions, a majority of the members of the Company’s board of directors cease to be directors during a 12 -month period. The Letter Agreement will terminate upon the earlier of (i) a change of control of Newco so long as Holdings and Newco have complied with their respective obligations described in the immediately preceding paragraph or (ii) the consummation of a sale of Holdings or Newco pursuant to a sale requested by Leucadia or its assignees as described above. The Letter Agreement includes a variety of restrictive covenants binding on Holdings and Newco, including, but not limited to: limitations on their ability to amend their organizational documents; limitations on their ability to dispose of assets; limitations on the incurrence of liens; limitations on the incurrence of debt by subsidiaries; and limitations on transactions with affiliates, without the prior consent of Leucadia and its assignees. In addition, there are restrictions on the Corporation’s ability to issue equity securities other than the issuance of equity awards to employees in the ordinary course of business. The Letter Agreement further provides that Holdings and Newco shall pay Leucadia’s expenses incurred in connection with the negotiation, execution and administration of such agreement. The Company evaluated the Letter Agreement to determine if it should be accounted for separately from the Credit Agreement. Pursuant to ASC 480, Distinguishing Liabilities from Equity ("ASC 480"), a financial instrument that is entered into in conjunction with some other transaction and is legally detachable and separately exercisable is a freestanding financial instrument and should be accounted for separately. Based on the Company’s review of the Letter Agreement, the Company concluded that the Letter Agreement is legally detachable from the Credit Agreement because it can be freely transferred. In addition, the Company determined that the Letter Agreement is separately exercisable since payments to the holder of the Letter Agreement are made after the repayment of the Credit Agreement. Accordingly, the Letter Agreement was determined to be a freestanding financial instrument and is accounted for separately from the Credit Agreement. Further, the Company concluded that the legal form of the Letter Agreement is equity. The Company considered the guidance in ASC 480 and determined that the accounting for the Letter Agreement does not fall within the scope of ASC 480 since the Letter Agreement is not mandatorily redeemable and will not require settlement by issuance of a variable number of equity shares. The Company then considered the guidance under ASC 815, Derivatives and Hedging ("ASC 815"), and concluded that several features of the Letter Agreement require bifurcation as embedded derivatives and should be accounted for as a derivative liability. The Company allocated the net proceeds of $279.0 million between the Credit Agreement and the Letter Agreement based on their relative fair values. The estimated fair values of the Letter Agreement and the Credit Agreement were determined using an option pricing model based on significant inputs such as volatility and assumptions on public market pricing inputs. The initially recorded amounts for the Letter Agreement and the Credit Agreement were approximately $94.4 million and $184.6 million , respectively, net of an issuance fee of $21.0 million . The effective interest method will be used to accrete the initial carrying value of the Credit Agreement liability to the par amount of the debt plus the $10.0 million deferred financing fee using an effective interest rate of 39.8% . The fair value of the Letter Agreement’s embedded derivatives that were required to be bifurcated totaled $124.8 million , which is in excess of the amount of proceeds initially allocated to the Letter Agreement, resulting in a charge to earnings of $30.4 million which is included in the condensed consolidated statements of operations for the six months ended June 30, 2015 . The Credit Agreement contains mandatory prepayment provisions in the event of certain events described above. The mandatory prepayments may be triggered by events or circumstances that are not considered clearly and closely related to the Credit Agreement, and, as such, represent embedded derivatives in accordance with ASC 815. As of June 30, 2016, a decline in the fair value of the Credit Agreement below par resulted in value attributable to the embedded derivatives. The Company assessed the fair value of the embedded derivatives and bifurcated their value from the fair value of the Credit Agreement. As of June 30, 2016 , the Company estimated the fair value of the derivative liability related to the embedded derivatives bifurcated from the Letter Agreement by using an enterprise valuation based on the traded (or closing) common stock price of the Corporation of $8.65 . The valuation approach incorporates an option pricing model for the allocation of enterprise value between the derivative liabilities resulting from the Letter and Credit Agreements, common stock and convertible debt. The valuation as of June 30, 2016 also incorporates assumptions that reflect the arrangements in the MOU and the restructuring of the agreement with Leucadia. In this regard, in estimating the fair value of the derivative liability as of June 30, 2016, the Company used a blended probability weighting approach that incorporated the assumptions underlying a restructuring scenario, i.e., the proposed arrangements in the MOU, and a non-restructuring scenario, i.e., the current terms of the Credit Agreement and the Letter Agreement. Since the Company believed the common stock price as of the valuation date had reflected the potential impact of the proposed amendments in the MOU, the Company assigned a higher weighting to the estimated fair value determined under the restructuring scenario and a lower weighting to the estimated fair value determined under the non-restructuring scenario. As of June 30, 2016 and December 31, 2015 , the fair value of the derivative liability resulting from the Letter Agreement was estimated at $209.5 million and $448.5 million , respectively, and is included in Derivative liability — Letter Agreement on the condensed consolidated statements of financial condition. The decline in the estimated fair value of the derivative liability as of June 30, 2016 resulted in a gain of $128.2 million and $239.0 million for the three and six months ended June 30, 2016 , respectively. The change in the estimated fair value of the derivative liability is recorded in Gain (loss) on derivative liabilities — Letter & Credit Agreements in the condensed consolidated statements of operations. The decrease in the estimated fair value of the derivative liability reflects a decline in the fair value of the Letter Agreement. The determination of the enterprise value and allocation of enterprise value using an option pricing model are based on significant inputs not observed in the market. In addition, the valuation methods are sensitive to certain key assumptions, such as volatility, that are not readily subject to contemporaneous or subsequent validation. For example, a $2.50 increase (decrease) in the common stock price of the Corporation would result in an increase of approximately $44.1 million (decrease of approximately $46.6 million ) in this valuation, assuming no change in any other factors considered. Separately, a 10% increase (decrease) in the assumed volatility would result in a decrease of approximately $0.6 million (increase of approximately $0.6 million ) in this valuation, assuming no other change in any other factors considered. As of June 30, 2016 , the Company estimated the fair value of the derivative liability related to the embedded derivatives bifurcated from the Credit Agreement by using the "with" and "without" method. Using this methodology, the Credit Agreement is first valued with the mandatory prepayment provision (the "with" scenario) and subsequently valued without the mandatory prepayment provision (the "without" scenario). The fair value of the derivative liability resulting from the mandatory prepayment provision is estimated as the difference between the fair values of the Credit Agreement in the "with" and "without" scenarios, probability-weighted for a restructuring scenario and a non-restructuring scenario using the assumptions described above. The fair value of the Credit Agreement in the "with" and "without" scenarios was estimated using a risk-neutral valuation model which models expected cash flows over the life of the debt. As of June 30, 2016 and December 31, 2015 , the fair value of the derivative liability resulting from the Credit Agreement was estimated at $11.6 million and nil , respectively, and is included in Credit Agreement on the condensed consolidated statements of financial condition. The change in the estimated fair value of the derivative liability at each reporting date is recorded in Gain (loss) on derivative liabilities — Letter & Credit Agreements in the condensed consolidated statements of operations. The determination of the value of the Credit Agreement using a risk-neutral valuation model is based on significant inputs not observed in the market. In addition, the valuation method is sensitive to certain key assumptions, such as expected recovery rate in the case of a default and the expected timing for the remaining businesses to be sold, that are not readily subject to contemporaneous or subsequent validation. The valuation techniques used are sensitive to the key assumptions noted above. For example, a 5.0% increase (decrease) in the recovery rate would result in a decrease of approximately $0.8 million (increase of approximately $0.5 million ) in this valuation, assuming no other change in any other factors considered. Separately, a $25.0 million acceleration (deceleration) in principal repayments would result in an increase of approximately $2.6 million (decrease of approximately $0.9 million ) in this valuation, assuming no other change in any other factors considered. The balance of the Credit Agreement as of June 30, 2016 and December 31, 2015 , was as follows, with amounts in thousands: As of June 30, 2016 December 31, 2015 Debt principal $ 192,543 $ 192,685 Original issue discount (18,898 ) (35,967 ) Discount — issuance fee (2,837 ) (5,227 ) Deferred financing fee (2,042 ) (3,762 ) Debt issuance costs (253 ) (467 ) Embedded derivative — Mandatory prepayment provision 11,640 — Debt — net carrying value $ 180,153 $ 147,262 Interest expense related to the Credit Agreement, included in Interest on borrowings in the condensed consolidated statements of operations for the three and six months ended June 30, 2016 and 2015 , consists of the following, with amounts in thousands: Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 Contractual interest $ 8,406 $ 6,653 $ 16,092 $ 12,901 Deferred interest (967 ) 2,168 (1,210 ) 4,852 Amortization of original issue discount 8,762 26,411 17,070 40,687 Amortization of issuance fee discount 1,248 3,539 2,390 5,318 Amortization of deferred financing fee 898 2,548 1,720 3,828 Amortization of debt issuance costs 111 316 213 475 Total interest expense — Credit Agreement $ 18,458 $ 41,635 $ 36,275 $ 68,061 The Company records deferred interest for the difference between the current period's contractual rate based on the loan terms and the amortization of the incremental step-up in the contractual rate over the life of the loan. The Company paid an issuance fee of $21.0 million to Jefferies LLC, an affiliate of Leucadia, at the inception of the loan. The issuance fee was allocated to the Credit Agreement and the Letter Agreement based on the initial fair value of the Credit Agreement and the Letter Agreement. The portion of the issuance fee allocated to the Credit Agreement was $13.9 million and the portion allocated to the Letter Agreement was $7.1 million . The portion allocated to the Credit Agreement is reflected as a discount to the Credit Agreement loan balance on the condensed consolidated statements of financial condition, and is recorded to Interest on borrowings using the effective interest method. Amortization of the issuance fee included in Interest on borrowings was $1.2 million and $2.4 million for the three and six months ended June 30, 2016 , respectively, and $3.5 million and $5.3 million for three and six months ended June 30, 2015 , respectively. The portion allocated to the Letter Agreement is reflected in Gain (loss) on derivative liability — Letter Agreement in the condensed consolidated statements of operations for the six months ended June 30, 2015 . The Company incurred $1.8 million of issuance costs related to both the Credit Agreement and Letter Agreement. The issuance costs were allocated to the Credit Agreement and Letter Agreement based on the initial fair value of the Credit Agreement and Letter Agreement. The issuance costs allocated to the Credit Agreement and Letter Agreement were $1.2 million and $0.6 million , respectively. Issuance costs allocated to the Credit Agreement were recorded as deferred issuance costs and will be amortized over the life of the Credit Agreement using the effective interest method. Amortization of Credit Agreement issuance costs included in Interest on borrowings was $0.1 million and $0.2 million for the three and six months ended June 30, 2016 , respectively, and $0.3 million and $0.5 million for the three and six months ended June 30, 2015 , respectively. The portion allocated to the Letter Agreement is reflected in Gain (loss) on derivative liability — Letter Agreement in the condensed consolidated statements of operations for the six months ended June 30, 2015 . As discussed in Note 2, as a result of the Company's adoption of ASU No. 2015-03 in the first quarter of 2016, unamortized debt issuance costs of $0.5 million as of December 31, 2015 were reclassified from Other assets, as previously reported, to the Credit Agreement liability on the condensed consolidated statements of financial condition. The deferred financing fee of $10.0 million will be amortized over the life of the Credit Agreement using the effective interest method. Amortization of the deferred financing fee included in Interest on borrowings was $0.9 million and $1.7 million for the three and six months ended June 30, 2016 , respectively, and $2.5 million and $3.8 million for the three and six months ended June 30, 2015 , respectively. The deferred financing fee was paid on April 1, 2015.

Debt

Debt	6 Months Ended
	Jun. 30, 2016
Debt Disclosure [Abstract]
Debt	Debt Revolving Credit Agreement In December 2011, Holdings entered into a credit agreement ("Revolving Credit Agreement") with a syndicate of financial institutions. In January 2015, in connection with the Leucadia Transaction, Holdings' outstanding balance under the Revolving Credit Agreement of $25.0 million was repaid in full and the Revolving Credit Agreement was terminated effective January 20, 2015. Interest expense related to borrowings under the Revolving Credit Agreement, including the amortization of debt financing costs, included in Interest on borrowings in the condensed consolidated statements of operations was nil and $1.5 million for the three and six months ended June 30, 2015 , respectively. For the same periods, the weighted average dollar amount of borrowings under the Revolving Credit Agreement was nil and $2.6 million , respectively, and the weighted average interest rates were nil and 2.9% , respectively. Senior Convertible Notes due 2018 In June 2013, the Corporation issued $172.5 million principal amount of 2.25% Convertible Notes maturing on June 15, 2018 and received net proceeds of $166.5 million , after deducting the initial purchasers' discount and offering expenses. The Convertible Notes pay interest semi-annually on June 15 and December 15 at a rate of 2.25% per year, commencing December 15, 2013. The indenture governing the Convertible Notes does not prohibit the Company from incurring additional senior debt or secured debt, nor does it prohibit any of its subsidiaries from incurring additional liabilities. The Convertible Notes will be convertible at an initial conversion rate of 5.32992 shares (after giving effect to the one-for-ten reverse stock split) of the Corporation's Class A common stock per $1,000 principal amount of the Convertible Notes, which is equivalent to an initial conversion price of approximately $187.62 (after giving effect to the one-for-ten reverse stock split). In addition, following certain corporate transactions that occur prior to the maturity date, the Corporation will, in certain circumstances, increase the conversion rate for a holder that elects to convert its Convertible Notes in connection with such corporate transaction. Upon conversion, the Corporation will deliver cash up to the principal amount. With respect to any conversion value in excess of the principal amount, the Corporation will deliver shares of its Class A common stock (unless it elects to deliver cash in lieu of all or a portion of such shares). Convertible Note Hedges In connection with the offering of the Convertible Notes, the Company entered into privately negotiated convertible note hedge transactions with certain counterparties (the “Convertible Note Hedge Transaction”). The Convertible Note Hedge Transactions will cover, subject to customary anti-dilution adjustments, the number of shares of the Corporation's Class A common stock that will initially underlie the Convertible Notes. Concurrently with entering into the Convertible Note Hedge Transaction, the Company also entered into a separate, privately negotiated warrant transaction (the “Warrant Transaction”) with the same counterparties, whereby the Company sold to the counterparties warrants to purchase, subject to customary anti-dilution adjustments, up to the same number of shares of the Corporation's Class A common stock as in the Convertible Note Hedge Transaction. The strike price of the Warrant Transaction will initially be $212.40 per share of the Corporation's Class A common stock (after giving effect to the one-for-ten reverse stock split). Subject to certain conditions, the Company may settle the warrants in cash or on a net-share basis. The Convertible Note Hedge Transaction and the Warrant Transaction have the effect of increasing the effective conversion price of the Convertible Notes to $212.40 per share (after giving effect to the one-for-ten reverse stock split). The cost of the Convertible Note Hedge Transaction and the proceeds from the Warrant Transaction was $29.1 million and $18.6 million , respectively. In accordance with ASC 815, the Company recorded the cost of the Convertible Note Hedge Transaction and the proceeds from the Warrant Transaction to additional paid-in capital in stockholders' equity in the condensed consolidated statements of financial condition and the recorded values will not be adjusted for subsequent changes in their respective fair values. The Convertible Note Hedge Transaction and the Warrant Transaction are separate transactions, in each case, entered into by the Company with certain counterparties, and are not part of the terms of the Convertible Notes and will not affect any holder's right under the Convertible Notes. Holders of the Convertible Notes will not have any rights with respect to the Convertible Hedge Transaction or the Warrant Transaction. Under ASC 470, an entity must separately account for the liability and equity components of the convertible debt instruments (such as the Convertible Notes) that may be settled entirely or partially in cash upon conversion in a manner that reflects the issuer's economic interest cost. The effect of ASC 470 on the accounting for the Convertible Notes is that the fair value of the equity component is included in additional paid-in capital in the stockholders' equity section of the Company's condensed consolidated statements of financial condition and the principal amount of the Convertible Notes is reduced by original issue discount to reflect the Convertible Notes fair value at issuance. At issuance, the equity component of the Convertible Notes was valued at $29.1 million and the Convertible Notes were valued at $144.1 million consisting of $172.5 million of principal net of original issuance discount of $29.1 million . The original issue discount will be amortized over the life of the Convertible Notes using the effective interest rate of 6.20% . The Company incurred $6.0 million of Convertible Notes issuance costs. The debt issuance costs will be amortized to interest expense over the life of the Convertible Notes. As discussed in Note 2, as a result of the Company's adoption of ASU No. 2015-03 in the first quarter of 2016, unamortized debt issuance costs of $2.9 million as of December 31, 2015 were reclassified from Other assets, as previously reported, to the Senior convertible notes liability on the condensed consolidated statements of financial condition. The balances of the liability and equity components as of June 30, 2016 and December 31, 2015 , were as follows, with amounts in thousands: As of June 30, 2016 December 31, 2015 Liability component — principal $ 172,500 $ 172,500 Deferred bond discount (12,380 ) (15,315 ) Deferred debt issuance costs (2,325 ) (2,930 ) Liability component — net carrying value $ 157,795 $ 154,255 Equity component $ 29,101 $ 29,101 Interest expense related to the Convertible Notes, included in Interest on borrowings in the condensed consolidated statements of operations, consists of the following, with amounts in thousands: Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 Stated coupon rate $ 971 $ 970 $ 1,941 $ 1,941 Amortization of deferred bond discount 1,471 1,384 2,935 2,761 Amortization of debt issuance cost 302 302 604 605 Total interest expense — Convertible Notes $ 2,744 $ 2,656 $ 5,480 $ 5,307

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Cybersecurity Incident In October 2015, the Company reported that it was the victim of a criminal cybersecurity incident involving unauthorized access to customer information. The Company received an email from a hacker claiming to have unlawful access to customer information. The Company immediately notified the FBI of this threat and cooperated with the FBI. In addition, the Company immediately launched a full investigation, working with a leading cybersecurity firm, and that investigation has been concluded. Based on the investigation, the Company identified a small number of unauthorized wire transfers from customer accounts; however, all funds have been returned to the appropriate accounts and the customers have been contacted. The Company did not find any evidence of an ongoing intrusion into its network or that additional customer information had been stolen from its network as part of the cybersecurity incident. The Company has incurred expenses subsequent to the cybersecurity incident to investigate and remediate this matter and may continue to incur expenses of this nature in future periods. Although the Company is unable to quantify the ultimate magnitude of such expenses and any other impact to the business from this incident at this time, they may be significant. These expenses will be recognized in the periods in which they are incurred. Through June 30, 2016 , the Company incurred $0.7 million of costs related to investigative and other professional services, costs of communications with customers and remediation activities associated with the incident. The costs incurred during the three and six months ended June 30, 2016 were nil and not material, respectively. The Company maintains insurance coverage for certain expenses of this nature, however, the coverage is subject to deductibles and may not be sufficient to entirely reduce the exposure to losses relating to this matter. During each of the three and six months ended June 30, 2016, the Company recorded $0.2 million in insurance recoveries for costs incurred related to the cybersecurity incident. The insurance recoveries are recorded in General and administrative expense in the condensed consolidated statements of operations. Guaranty In July 2015, the Company entered into a guaranty with Citibank, N.A. (the "Guaranty") following the transition of certain institutional customers from the Company to FastMatch (see Note 10). Under the terms of the Guaranty, the Company agreed to guaranty FastMatch for any liabilities and other amounts that became due and payable by FastMatch for services provided by Citibank N.A. as the intermediating counterparty for trading transactions executed on the FastMatch platform. The Guaranty expired on March 1, 2016 and was not renewed. No payments were made by the Company to Citibank N.A. under the terms of the Guaranty.

Derivative Financial Instrument

Derivative Financial Instruments	6 Months Ended
	Jun. 30, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	Derivative Financial Instruments Derivative financial instruments are accounted for in accordance with ASC 815 and are recognized as either assets or liabilities at fair value on the condensed consolidated statements of financial condition. The Company has master netting agreements with its respective counterparties under which derivative financial instruments are presented on a net-by-counterparty basis in accordance with ASC 210 and ASC 815. The Company enters into futures contracts or CFD contracts to economically hedge the open customer contracts and positions on its CFD business. Futures contracts are exchange traded contracts to either purchase or sell a specific asset at a specified future date for a specified price. CFD contracts are non-exchange traded contracts between a buyer and seller to exchange the difference in the value of an underlying asset at the beginning and end of a stated period. The Company's derivative assets and liabilities associated with futures contracts and CFD contracts on its CFD business are recorded within Due from brokers and Due to brokers, respectively, on the condensed consolidated statements of financial condition and gains or losses on these transactions are included in Trading revenue in the condensed consolidated statements of operations. Through its subsidiaries Lucid and V3, the Company also engages in hedge trading in its electronic market making and institutional foreign exchange spot and futures markets. As discussed in Note 4, Lucid and V3 are reported as discontinued operations for all periods presented. Accordingly, the gains or losses on hedge trading in the Company's electronic market making and institutional foreign exchange spot and futures markets are included in Income (loss) from discontinued operations, net of tax in the condensed consolidated statements of operations. The Company also enters into options, futures, forward foreign currency contracts and commodity contracts through Lucid and V3. Options grant the purchaser, for the payment of a premium, the right to either purchase from or sell to the writer a specified instrument under agreed terms. A forward contract is a commitment to purchase or sell an asset at a future date at a negotiated rate. The Company's derivative assets and liabilities held for trading purposes in connection with Lucid and V3 are recorded in Current assets held for sale and Current liabilities held for sale, respectively, on the condensed consolidated statements of financial condition. Gains or losses on options, futures and forward contracts held for trading purposes in connection with Lucid and V3 are included in Income (loss) from discontinued operations, net of tax in the condensed consolidated statements of operations. The Company is exposed to risks relating to its derivatives trading positions from the potential inability of counterparties to perform under the terms of the contracts (credit risk) and from changes in the value of the underlying financial instruments (market risk). The Company is subject to credit risk to the extent that any counterparty with which it conducts business is unable to fulfill its contractual obligations. The Company manages its trading positions by monitoring its positions with and the credit quality of the financial institutions that are party to its derivative trading transactions. Additionally, the Company's netting agreements provide the Company with the right, in the event of a default of the counterparty (such as bankruptcy or a failure to perform), to net a counterparty’s rights and obligations under the agreement and to liquidate and set off collateral against any net amount owed by the counterparty. The following tables present the gross and net fair values of the Company's derivative transactions and the related offsetting amount permitted under ASC 210 and ASC 815 as of June 30, 2016 and December 31, 2015 . Derivative assets and liabilities are net of counterparty and collateral offsets. Collateral offsets include cash margin amounts posted with brokers. Under ASC 210, gross positive fair values are offset against gross negative fair values by counterparty pursuant to enforceable master netting agreements, with amounts in thousands: As of June 30, 2016 Derivative Assets Derivative Liabilities Statement of Financial Condition Location Fair Value Notional Fair Value Notional Exchange traded options Current assets/liabilities held for sale (1) $ 9,907 $ 30,007 $ — $ — CFD contracts Due from/Due to brokers (2) 2 1,863 — — Futures contracts Due from/Due to brokers and Current assets/liabilities held for sale (1), (2) 720 39,839 19,920 1,754,330 OTC options Current assets/liabilities held for sale (1) 1,255 74,245 1,511 69,024 Total derivatives, gross $ 11,884 $ 145,954 $ 21,431 $ 1,823,354 Netting agreements and cash collateral netting (9,037 ) (9,037 ) Total derivatives, net $ 2,847 $ 12,394 ____________________________________ (1) As of June 30, 2016 , the aggregate fair values of derivative assets and liabilities, gross attributable to discontinued operations is $11.6 million and $9.0 million , respectively. These amounts are offset by netting agreements and cash collateral netting of $8.8 million and $8.8 million , respectively. (2) As of June 30, 2016 , the aggregate fair values of derivative assets and liabilities, gross attributable to continuing operations is $0.3 million and $12.4 million , respectively. These amounts are offset by netting agreements and cash collateral netting of $0.3 million and $0.3 million , respectively. As of December 31, 2015 Derivative Assets Derivative Liabilities Statement of Financial Condition Location Fair Value Notional Fair Value Notional Exchange traded options Current assets/liabilities held for sale (3) $ 6,503 $ 15,399 $ 5,805 $ 18,282 CFD contracts Due from/Due to brokers (4) 206 109,715 36 99,036 Futures contracts Due from/Due to brokers and Current assets/liabilities held for sale (3), (4) 4,212 794,960 3,102 1,047,239 Total derivatives, gross $ 10,921 $ 920,074 $ 8,943 $ 1,164,557 Netting agreements and cash collateral netting (8,909 ) (8,909 ) Total derivatives, net $ 2,012 $ 34 ____________________________________ (3) As of December 31, 2015 , the aggregate fair values of derivative assets and liabilities, gross attributable to discontinued operations is $9.7 million and $8.8 million , respectively. These amounts are offset by netting agreements and cash collateral netting of $8.8 million and $8.8 million , respectively. (4) As of December 31, 2015 , the aggregate fair value of derivative assets and liabilities, gross attributable to continuing operations is $1.2 million and $0.1 million , respectively. These amounts are offset by netting agreements and cash collateral netting of $0.1 million and $0.1 million , respectively. Gains (losses) on the Company's derivative instruments are recorded on a trade date basis. The following table presents the gains (losses) on derivative instruments recognized in the condensed consolidated statements of operations for the three and six months ended June 30, 2016 and 2015 , with amounts in thousands: Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 Exchange traded options (5) $ 737 $ 1,176 $ 11,091 $ (729 ) CFD contracts (6) (1,305 ) 415 (1,445 ) (5,347 ) Futures contracts (7) (15,736 ) 18,000 (30,856 ) 38,062 OTC options (5) (10 ) — 2 1,086 Total $ (16,314 ) $ 19,591 $ (21,208 ) $ 33,072 ____________________________________ (5) Included in Income (loss) from discontinued operations, net of tax in the condensed consolidated statements of operations for all periods presented. (6) Included in Trading revenue in the condensed consolidated statements of operations for all periods presented. (7) The portion included in Income (loss) from continuing operations in the condensed consolidated statements of operations is $(17.7) million and $(25.3) million for the three and six months ended June 30, 2016 , respectively, and $11.1 million and $18.3 million for the three and six months ended June 30, 2015 , respectively.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Fair value measurement establishes a fair value hierarchy that prioritizes the inputs of valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities and the lowest priority to unobservable inputs. The three levels of fair value hierarchy are defined as follows: Level 1 : Quoted prices in active markets for identical assets or liabilities, accessible by the Company at the measurement date. Level 2 : Quoted prices for similar assets or liabilities in active markets, or quoted prices for identical or similar assets or liabilities in markets that are not active, or other observable inputs other than quoted prices. Level 3 : Unobservable inputs for assets or liabilities. When Level 1 inputs are available, those inputs are selected for determination of fair value. To value financial assets or liabilities that are characterized as Level 2 and 3, the Company uses observable inputs for similar assets and liabilities that are available from pricing services or broker quotes. These observable inputs may be supplemented with other methods, including internal models that result in the most representative prices for assets and liabilities with similar characteristics. Multiple inputs may be used to measure fair value, however, the fair value measurement for each financial asset or liability is categorized in its entirety in the same level of the fair value hierarchy as the lowest level input that is significant to the entire measurement. The following tables present the Company's assets and liabilities that are measured at fair value on a recurring basis and the related hierarchy levels, with amounts in thousands: Fair Value Measurements on a Recurring Basis As of June 30, 2016 Level 1 Level 2 Level 3 Counterparty and Cash Collateral Netting Total Financial Assets: Derivative assets: Exchange traded options $ 9,907 $ — $ — $ — $ 9,907 CFD contracts — 2 — — 2 Futures contracts 720 — — — 720 OTC options — 1,255 — — 1,255 Netting — — — (9,037 ) (9,037 ) Total derivative assets (1) 10,627 1,257 — (9,037 ) 2,847 Total assets $ 10,627 $ 1,257 $ — $ (9,037 ) $ 2,847 Financial Liabilities: Customer account liabilities $ — $ 662,392 $ — $ — $ 662,392 Derivative liabilities: Futures contracts 19,920 — — — 19,920 OTC options — 1,511 — — 1,511 Netting — — — (9,037 ) (9,037 ) Total derivative liabilities (1) 19,920 1,511 — (9,037 ) 12,394 Securities sold, not yet purchased (2) 3,896 — — — 3,896 Letter Agreement — — 209,458 — 209,458 Mandatory Prepayment Provision — Credit Agreement — — 11,640 — 11,640 Total liabilities $ 23,816 $ 663,903 $ 221,098 $ (9,037 ) $ 899,780 As of June 30, 2016 , the Company's total notional absolute value of open FX and CFD customer assets and liabilities by currency pair or product was $1.4 billion and $1.8 billion , respectively. The Company's total net notional value for open FX and CFD positions was $1.5 billion . Fair Value Measurements on a Recurring Basis As of December 31, 2015 Level 1 Level 2 Level 3 Counterparty and Cash Collateral Netting Total Financial Assets: Derivative assets: Exchange traded options $ 6,503 $ — $ — $ — $ 6,503 CFD contracts — 206 — — 206 Futures contracts 4,212 — — — 4,212 Netting — — — (8,909 ) (8,909 ) Total derivative assets (1) 10,715 206 — (8,909 ) 2,012 Total assets $ 10,715 $ 206 $ — $ (8,909 ) $ 2,012 Financial Liabilities: Customer account liabilities $ — $ 685,043 $ — $ — $ 685,043 Derivative liabilities: Exchange traded options 5,805 — — — 5,805 CFD contracts — 36 — — 36 Futures contracts 3,102 — — — 3,102 Netting — — — (8,909 ) (8,909 ) Total derivative liabilities (1) 8,907 36 — (8,909 ) 34 Securities sold, not yet purchased (2) 3,624 — — — 3,624 Letter Agreement — — 448,458 — 448,458 Total liabilities $ 12,531 $ 685,079 $ 448,458 $ (8,909 ) $ 1,137,159 As of December 31, 2015 , the Company's total notional absolute value of open FX and CFD customer assets and liabilities by currency pair or product was $2.5 billion and $2.5 billion , respectively. The Company's total net notional value for open FX and CFD positions was $2.2 billion . ____________________________________ (1) Attributable to continuing and discontinued operations. See Note 15 for details of the classification of amounts on the condensed consolidated statements of financial condition. (2) Attributable to discontinued operations. Amounts classified as held for sale on the condensed consolidated statements of financial condition (see Note 4). Derivative Assets and Liabilities Exchange traded options and open futures contracts are measured at fair value based on exchange prices. CFD contracts and over-the-counter ("OTC") options are measured at fair value based on market price quotations (where observable) obtained from independent brokers. Customer Account Liabilities Customer account liabilities represent amounts due to customers related to cash and margin transactions, including cash deposits and gains and losses on settled FX, CFDs and spread betting trades as well as unrealized gains and losses on open FX commitments, CFDs and spread betting. Customer account liabilities, included in the condensed consolidated statements of financial condition, are measured at fair value based on the market prices of the underlying products. Securities Sold, Not Yet Purchased Securities sold, not yet purchased, represent the Company’s obligations to deliver the specified security at the contracted price at a future point in time, and thereby create a liability to repurchase the securities in the market at the prevailing prices. The liability for such securities sold short, included on the condensed consolidated statements of financial condition, is marked to market based on the current fair value of the underlying security at the reporting date which is determined based on exchange prices. Changes in fair value of securities sold, not yet purchased are recorded in Income (loss) from discontinued operations, net of tax in the condensed consolidated statements of operations. These transactions may involve market risk in excess of the amount currently reflected in the condensed consolidated statements of financial condition. Letter Agreement The embedded derivatives bifurcated from the Letter Agreement are accounted for separately as a derivative liability. The fair value of the derivative liability resulting from the Letter Agreement is determined by the use of valuation techniques that incorporate a combination of Level 1 and Level 3 inputs. The Level 1 input is comprised of the common stock price of the Corporation. The significant Level 3 inputs are considered more relevant in the analysis and are given a higher weighting in the overall fair value determination (see Note 12). The following table summarizes the significant Level 3 inputs used in the fair value determination of the Letter Agreement as of June 30, 2016 and December 31, 2015 , respectively: As of Valuation Technique Significant Unobservable Inputs June 30, 2016 December 31, 2015 Option-Pricing Method Term (years) 2.0 2.5 Volatility 133.6 % 79.1 % Risk-free rate 0.6 % 1.2 % Dividend yield — % — % Reliance placed on public indication of value 100.0 % 100.0 % The derivative liability resulting from the Letter Agreement, included on the condensed consolidated statements of financial condition, is marked to market at the reporting date and changes in the fair value are recorded through earnings in the condensed consolidated statements of operations as gains or losses resulting from the Letter Agreement. The valuation techniques used are sensitive to the key assumptions noted above. For example, a 10% increase (decrease) in the assumed volatility would result in a decrease of approximately $0.6 million (increase of approximately $0.6 million ) in this valuation, assuming no other change in any other factors considered. Mandatory Prepayment Provision — Credit Agreement The Credit Agreement contains mandatory prepayment provisions that may be triggered by events or circumstances that are not considered clearly and closely related to the Credit Agreement, such as asset sales, and, as such, represent embedded derivatives in accordance with ASC 815. The embedded derivatives are bifurcated from the Credit Agreement and accounted for separately as a derivative liability. The fair value of the derivative liability resulting from the mandatory prepayment provisions of the Credit Agreement is estimated using the "with" and "without" method. Using this methodology, the Credit Agreement is first valued with the mandatory prepayment provision (the "with" scenario) and subsequently valued without the mandatory prepayment provision (the "without" scenario). This is performed using assumptions separately underlying a restructuring scenario and a non-restructuring scenario (see Note 12). The fair value of the derivative liability resulting from the mandatory prepayment provision is estimated as the difference between the fair values of the Credit Agreement in the "with" and "without" scenarios, weighted for the probability of occurrence of a restructuring and a non-restructuring (see Note 12). The fair value of the Credit Agreement in the "with" and "without" scenarios was estimated using a risk-neutral valuation model. Specifically, to estimate the fair value of the Credit Agreement, the expected cash flows were modeled over the life of the debt. The valuation of the derivative liability resulting from the mandatory prepayment provision primarily utilizes Level 3 inputs. The significant Level 3 inputs include the expected recovery rate in the case of a default and the expected timing for the remaining businesses to be sold. A recovery rate of 53.4% was used in the valuation as of June 30, 2016 , which was estimated using market observed long-term average recovery rates for debt instruments of similar seniority. The timing for the remaining businesses to be sold was estimated by management and ranged from the third quarter of 2016 to the first half of 2017. The derivative liability resulting from the mandatory prepayment provision, included in the Credit Agreement on the condensed consolidated statements of financial condition, will be marked to market at each reporting date and changes in the fair value will be recorded through earnings in the condensed consolidated statements of operations as gains or losses resulting from the Credit Agreement. The valuation techniques used are sensitive to the key assumptions noted above. For example, a 5.0% increase (decrease) in the recovery rate would result in a decrease of approximately $0.8 million (increase of approximately $0.5 million ) in this valuation, assuming no other change in any other factors considered. Separately, a $25.0 million acceleration (deceleration) in principal repayments would result in an increase of approximately $2.6 million (decrease of approximately $0.9 million ) in this valuation, assuming no other change in any other factors considered. The following tables present the carrying value, fair value and fair value hierarchy category of certain financial instruments that are not measured at fair value in the condensed consolidated statements of financial condition, with amounts in thousands: As of June 30, 2016 Fair Value Measurements using: Carrying Value Fair Value Level 1 Level 2 Level 3 Financial Assets: Due from brokers — unsettled spot FX (4) $ 2,161 $ 2,161 $ — $ 2,161 $ — Due from brokers — unsettled common stock (5) 3,054 3,054 — 3,054 — Due from brokers — excess cash collateral (5) 12,559 12,559 — 12,559 — Equity method investments (4) 6,505 12,800 — — 12,800 Cost method investment 1,103 1,103 — — 1,103 Exchange memberships (5) 9,434 9,249 — 9,249 — Total assets $ 34,816 $ 40,926 $ — $ 27,023 $ 13,903 Financial Liabilities: Due to brokers — unsettled spot FX (4) $ 38 $ 38 $ — $ 38 $ — Senior convertible notes 157,795 59,944 — 59,944 — Credit Agreement 180,153 164,253 — — 164,253 Total liabilities $ 337,986 $ 224,235 $ — $ 59,982 $ 164,253 As of December 31, 2015 Fair Value Measurements using: Carrying Value Fair Value Level 1 Level 2 Level 3 Financial Assets: Due from brokers — unsettled spot FX (4) $ 2,939 $ 2,939 $ — $ 2,939 $ — Due from brokers — unsettled common stock (5) 3,054 3,054 — 3,054 — Due from brokers — excess cash collateral (5) 18,010 18,010 — 18,010 — Equity method investments (4) 8,273 19,043 — — 19,043 Notes receivable 7,881 7,881 — — 7,881 Exchange memberships (5) 9,434 8,655 — 8,655 — Total assets $ 49,591 $ 59,582 $ — $ 32,658 $ 26,924 Financial Liabilities: Due to brokers — unsettled spot FX (4) $ 1,039 $ 1,039 $ — $ 1,039 $ — Senior convertible notes 157,185 121,187 — 121,187 — Credit Agreement 147,729 192,685 — — 192,685 Total liabilities $ 305,953 $ 314,911 $ — $ 122,226 $ 192,685 ____________________________________ (4) Attributable to continuing and discontinued operations. See Note 4 for amounts classified as held for sale on the condensed consolidated statements of financial condition. (5) Attributable to discontinued operations and included in assets held for sale on the condensed consolidated statements of financial condition (see Note 4). Due from/to Brokers — Unsettled Spot FX Unsettled spot FX, included in Due from/Due to brokers and assets and liabilities held for sale on the condensed consolidated statements of financial condition, is carried at contracted amounts which approximate fair value based on market price quotations (where observable) obtained from independent brokers. Due from Brokers — Unsettled Common Stock The receivable for exchange membership shares sold short, included in assets held for sale on the condensed consolidated statements of financial condition, is carried at the contracted amount which approximates fair value based on quoted prices. Due from Brokers — Excess Cash Collateral Excess cash collateral, included in assets held for sale on the condensed consolidated statements of financial condition, is carried at contractual amounts which approximate fair value. Equity Method Investments Equity method investments are carried at cost. The fair value of these investments is based on comparable market multiples and other valuation methods. Cost Method Investment The cost method investment, included in Other assets on the condensed consolidated statements of financial condition, is carried at cost. The fair value of this investment is based on an independent valuation under a market-based approach. Notes Receivable Notes receivable are carried at contracted amounts which approximate fair value. Exchange Memberships Exchange memberships, which include ownership interests and shares owned, are carried at cost. The fair value is based on quoted prices or recent sales. Senior Convertible Notes Senior convertible notes are carried at contractual amounts. The fair value of the Senior convertible notes is based on similar recently executed transactions and market price quotations (where observable) obtained from independent brokers. Credit Agreement Credit Agreement is carried at the contracted amount less original issue discount. The fair value of the Credit Agreement is based on a valuation model that considers the probability of default, Leucadia's secured interest, and the observable trading value of the Senior convertible notes. The following tables reconcile the opening and ending balances of the recurring fair value measurements categorized as Level 3, which are included in the condensed consolidated statements of financial condition, and identifies the total gains and losses the Company recognized during the three and six months ended June 30, 2016 and 2015 , with amounts in thousands: Three Months Ended June 30, 2016 Balance as of Additions Net Unrealized Balance as of Letter Agreement $ 337,627 $ — $ (128,169 ) $ 209,458 Mandatory Prepayment Provision — Credit Agreement — 11,640 — 11,640 Total Level 3 liabilities $ 337,627 $ 11,640 $ (128,169 ) $ 221,098 Six Months Ended June 30, 2016 Balance as of Additions Net Unrealized Balance as of Letter Agreement $ 448,458 $ — $ (239,000 ) $ 209,458 Mandatory Prepayment Provision — Credit Agreement — 11,640 — 11,640 Total Level 3 liabilities $ 448,458 $ 11,640 $ (239,000 ) $ 221,098 Three Months Ended June 30, 2015 Balance as of Additions Net Unrealized Balance as of Letter Agreement $ 386,230 $ — $ 99,867 $ 486,097 Total Level 3 liabilities $ 386,230 $ — $ 99,867 $ 486,097 Six Months Ended June 30, 2015 Balance as of Additions Net Unrealized Balance as of Letter Agreement $ — $ 94,436 $ 391,661 $ 486,097 Total Level 3 liabilities $ — $ 94,436 $ 391,661 $ 486,097 The net unrealized gains and losses summarized in the tables above are related to the changes in the fair value of the Letter Agreement for the three and six months ended June 30, 2016 and 2015 and are included in Gain (loss) on derivative liability — Letter Agreement in the condensed consolidated statements of operations. There were no transfers into or out of Level 1, 2 or 3 of the fair value hierarchy during the three and six months ended June 30, 2016 and 2015 .

Stockholders' Equity

Stockholders' Equity	6 Months Ended
	Jun. 30, 2016
Equity [Abstract]
Stockholders' Equity	Stockholders' Equity Amendment to Stockholder Rights Plan On January 26, 2016, the Company entered into an Amended and Restated Rights Agreement (the “Amended Rights Agreement”) which amended the Company’s original Rights Agreement (the “Original Rights Agreement”) dated January 29, 2015. In connection with the adoption of the Original Rights Agreement, the Corporation's Board of Directors declared a dividend distribution of one right on each outstanding share of the Corporation's Class A common stock. The Original Rights Agreement was amended to protect the interests of the Company and its stockholders by helping to preserve the value of the Company’s net operating loss carryforwards and tax credits. Under the terms of the Amended Rights Agreement, each right initially entitles stockholders to buy one one-thousandth (1/1000) of a share of the Series A Junior Participating Preferred Stock of the Corporation, at an initial exercise price of $44.12 , in the event the rights become exercisable. As amended, the rights generally become exercisable if a person or group becomes the beneficial owner of 4.9% or more of (a) the outstanding Class A common stock of the Corporation or (b) the fair market value of all capital stock of the Corporation. Prior to this amendment, the beneficial ownership percentage threshold to trigger the rights plan was 10.0% of all voting securities, a trigger that, after this amendment, remains in place in addition to the aforementioned 4.9% trigger. The Amended Rights Agreement extends the expiration date of the rights from January 29, 2018 to January 26, 2019, unless the rights are earlier redeemed or exchanged in accordance with the Amended Rights Agreement or the Amended Rights Agreement is earlier terminated by the Company’s Board of Directors. As of June 30, 2016 , the Company is not aware of the occurrence of any events that would trigger the exercise of the rights under the Amended Rights Agreement. This amendment is not a taxable event, will not affect the reported financial condition or results of operations, including earnings per share, of the Corporation and will not change the manner in which the Corporation’s Class A common stock is currently traded. Reverse Stock Split A one-for-ten reverse split of the Corporation's issued and outstanding Class A common stock (the "Reverse Stock Split") became effective at the opening of trading on the NYSE on October 1, 2015 (the "Effective Date"). As of the Effective Date, every ten shares of issued and outstanding Class A common stock were combined into one newly issued share of Class A common stock. All references to number of Class A common shares, number of Holdings Units, price per share and weighted average shares of Class A common stock have been adjusted to reflect the Reverse Stock Split on a retroactive basis for all prior periods presented, unless otherwise noted. Option Agreement On April 15, 2015, the Company entered into an Option Agreement (the “Option Agreement”) pursuant to which the Company issued an option to purchase 56,934 shares of the Corporation’s Class A common stock (the “Option”) with an exercise price of $22.50 (after giving effect to the one-for-ten reverse stock split). The Option was exercisable immediately, expires two years from the date of issuance, and includes standard anti-dilution protections. The Option Agreement was entered into as part of a negative equity balance settlement with a customer. The fair value of the Option on the date of issuance was estimated at $0.3 million and was determined using the Black-Scholes-Merton option pricing model.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2016
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Holdings operates in the U.S. as a limited liability company that is treated as a partnership for U.S. federal, state and local income tax purposes. Since January 2015, all of Holdings' operations are held by Newco, a limited liability company that is also treated as a partnership between Holdings and Leucadia for U.S. federal, state and local income tax purposes. As a result, neither Holdings' nor Newco's income from its U.S. operations is subject to U.S. federal income tax because the income is attributable to its members. Accordingly, the Company’s U.S. tax provision is solely based on the portion of income attributable to the Corporation from the lower tier limited liability companies and excludes the income attributable to other members of Holdings whose income is included in Net income (loss) attributable to non-controlling interest in FXCM Holdings, LLC in the condensed consolidated statements of operations. In addition to U.S. federal and state income taxes, the Company is subject to Unincorporated Business Tax which is attributable to Newco's operations apportioned to New York City. The Company’s foreign subsidiaries are also subject to taxes in the jurisdictions in which they operate. The Company’s effective tax rate was (0.5)% for the three months ended June 30, 2016 compared to (1.0)% for the three months ended June 30, 2015 . The Company's effective tax rate was 0.1% for the six months ended June 30, 2016 compared to (30.0)% for the six months ended June 30, 2015 . The negative tax rate for the three months ended June 30, 2016 reflects the recording of a tax benefit on the income for the period while the negative tax rates for the three and six months ended June 30, 2015 reflect the recording of a tax provision on a book loss. The tax rate for the three months ended June 30, 2016 is predominately the result of providing a tax benefit on the loss recorded by the Company's UK subsidiary. Also, during the second quarter of 2016, the Company reversed $23.6 million of valuation allowance against the income generated. The provision for the three months ended June 30, 2015 principally reflects recording a valuation allowance against the loss for the period thereby decreasing the tax benefit attributable to the loss. During the second quarter of 2015, similar to the first quarter of 2015, the Corporation determined that, given the losses incurred from the events of January 15, 2015 and due to the Leucadia Transaction, it was not more likely than not that it would benefit from the tax deduction attributable to the tax basis step-up from the conversion of the non-controlling membership units of Holdings, nor would it benefit from the tax benefit of the losses incurred during the quarter. Therefore, the Company recorded a valuation allowance in the second quarter of 2015 on its deferred tax assets of $57.3 million due to the Company's realizability assessment. During the six months ended June 30, 2016 , there were no material changes to the uncertain tax positions. The Company is no longer subject to tax examinations by taxing authorities for tax years prior to 2011. During the third quarter of 2015, the Company was notified that its 2013 federal tax return was subject to examination by the Internal Revenue Service ("IRS"). Certain of the Company’s UK subsidiaries are also currently subject to examination.

Litigation

Litigation	6 Months Ended
	Jun. 30, 2016
Commitments and Contingencies Disclosure [Abstract]
Litigation	Litigation In the ordinary course of business, we and certain of our officers, directors and employees may from time to time be involved in litigation and claims incidental to the conduct of our businesses, including intellectual property claims. In addition, our business is also subject to extensive regulation, which may result in administrative claims, investigations and regulatory proceedings against us. We have been named in various arbitration and civil litigation cases brought by customers seeking damages for trading losses. Management has investigated these matters and believes that such cases are without merit and is defending them vigorously. However, the arbitrations and litigations are presently in various stages of the judicial process and no judgment can be made regarding the ultimate outcome of the arbitrators’ and/or court’s decisions. In January 2014, the equity receiver for a former client of US, Revelation Forex Fund (“Revelation”), its principal, Kevin G. White, and related entities RFF GP, LLC and KGM Capital Management, LLC, filed suit against US, and certain unrelated defendants, in Texas state court. The suit alleges that US is liable for damages in excess of $3.8 million , plus exemplary damages, interest, and attorneys’ fees in connection with a Ponzi scheme run by Mr. White through his companies. In June 2015, that same equity receiver filed a complaint against US seeking $2.0 million , plus interest, and attorneys’ fees, based on allegations that the amount in controversy represents the net fraudulent transfers from Revelation to US under New York law. In September 2015, the parties agreed to arbitration before the National Futures Association on these claims. In June 2016, the parties agreed to settle all related matters for $2.3 million . The settlement is reflected in General and administrative expense in the condensed consolidated statements of operations for the three and six months ended June 30, 2016. In April 2014, the Securities and Futures Commission ("SFC") initiated an investigation relating to HK’s past trade execution practices concerning the handling of price improvements in our trading system prior to August 2010. The Company is engaged in ongoing discussions with the SFC and continues to comply with information requests from the SFC. The Company has accrued $2.0 million in connection with this matter, including a charge of $0.5 million for potential fines recorded in discontinued operations for the three and six months ended June 30, 2016. On January 15, 2015, as a result of the unprecedented volatility in the EUR/CHF currency pair after the SNB discontinued its currency floor of 1.2 CHF per EUR, US suffered a temporary breach of certain regulatory capital requirements. Following the SNB event, the CFTC initiated an investigation relating to US’s adjusted net capital and minimum financial requirement computations. US continues to comply with information requests from CFTC. In connection with an earlier settlement between FSL and the Financial Conduct Authority regarding trade execution practices for the period 2006 to 2010, in February 2015, FSL paid an additional $0.7 million in restitution to affected clients. On May 8, 2015, the International Union of Operating Engineers Local No. 478 Pension Fund filed a complaint against the Company, its Chief Executive Officer and its Chief Financial Officer in the United States District Court for the Southern District of New York, individually and on behalf of all purchasers of the Company's common stock between June 11, 2013 and January 20, 2015. The complaint alleges that the defendants violated certain provisions of the federal securities laws and seeks compensatory damages as well as reasonable costs and expenses. An amended and consolidated complaint was filed on January 11, 2016. The Company filed a motion to dismiss the consolidated complaint on February 25, 2016, plaintiffs filed an opposition brief on April 11, 2016, and the Company filed a reply brief on May 11, 2016. The Company and board members intend to vigorously defend the allegations in the amended complaint. In September 2015, US settled a complaint brought by the Commodity Futures Trading Commission (“CFTC”) alleging that US failed to supervise an account determined to have been involved in wrongdoing and inadvertently omitted certain documents from its responses to document request. Under the terms of the settlement, US agreed, without admitting or denying any of the allegations, to pay a fine of $0.7 million to the CFTC and disgorge commissions and fees of $0.1 million . On December 15, 2015, Brett Kandell, individually and on behalf of nominal defendant, FXCM Inc., filed a shareholder derivative complaint against the members of FXCM’s board of directors in the Court of Chancery for the State of Delaware. The case is captioned Brett Kandell v. Dror Niv et al. , C.A. No. 11812-VCG. On March 4, 2016, plaintiff filed an amended shareholder derivative complaint, which alleges claims for breach of fiduciary duty, contribution and indemnification, waste of corporate assets, abuse of control and unjust enrichment and seeks compensatory damages, rescission of certain agreements as well as reasonable costs and expenses. A second amended shareholder derivative complaint was filed on May 31, 2016 and the Company filed a motion to dismiss on July 15, 2016. The Company and board members intend to vigorously defend the allegations in the second amended complaint. For the outstanding matters referenced above, including ordinary course of business litigation and claims referenced in the first paragraph hereto, for which a loss is more than remote but less than likely, whether in excess of an accrued liability or where there is no accrued liability, we have estimated a range of possible loss. Management believes the estimate of the aggregate range of possible loss in excess of accrued liabilities for such matters is between nil and $1.5 million as of June 30, 2016 . In view of the inherent difficulty of predicting the outcome of litigation and claims, we cannot predict what the eventual outcome of the pending matters will be, what the timing of the ultimate resolution of these matters will be, or what the eventual loss related to each pending matter may be. Furthermore, the above-referenced matters represented in the estimated aggregate range of possible loss will change from time to time and actual results may vary significantly from the current estimate. An adverse outcome in one or more of these matters could be material to our results of operations or cash flows for any particular reporting period.

Subsequent Events

Subsequent Events	6 Months Ended
	Jun. 30, 2016
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events The Company has evaluated its subsequent events through the filing date of this Form 10-Q.

Significant Accounting Polici29

Significant Accounting Policies and Estimates (Policies)	6 Months Ended
	Jun. 30, 2016
Accounting Policies [Abstract]
Basis of Consolidation	Basis of Consolidation The accompanying condensed consolidated financial statements are presented in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). The Company consolidates those entities in which it is the primary beneficiary of a variable interest entity ("VIE") as required by Financial Accounting Standards Board (“FASB”) Accounting Standards Codification Topic (“ASC”) 810, Consolidations (“ASC 810”), or entities where it has a controlling interest. Intercompany accounts and transactions are eliminated in consolidation. As indicated above, in January 2015, Holdings transferred its interest in its operating subsidiaries to Newco, a wholly-owned subsidiary of Holdings formed in connection with the Leucadia Transaction (see Note 12). The Leucadia Transaction provided the financing needed in order for the operating subsidiaries of Holdings and Newco to maintain compliance with regulatory capital requirements and continue operations. The Company determined that Newco is a VIE and concluded that Holdings is the primary beneficiary of Newco since Holdings has the ability to direct the activities of Newco that most significantly impact Newco’s economic performance and the obligation to absorb losses of Newco or the right to receive benefits from Newco that could be significant to Newco. As a result, Holdings consolidates the financial results of Newco. The Corporation records a non-controlling interest for the economic interest in Holdings not owned by the Corporation. The Corporation’s and the non-controlling unit holders’ economic interest in Holdings was 67.9% and 32.1% , respectively, as of both June 30, 2016 and December 31, 2015 . The Company’s condensed consolidated financial statements include the following significant subsidiaries of Holdings: FXCM Newco, LLC (“Newco”) FXCM Global Services, LLC (“Global Services”) Forex Capital Markets LLC (“US”) FXCM Asia Limited** (“HK”) Forex Capital Markets Limited (“UK LTD”) FXCM Australia Pty. Limited (“Australia”) ODL Group Limited (“ODL”) FXCM Securities Limited*** (“FSL”) FXCM Japan Securities Co., Ltd.* (“FXCMJ”) FXCM UK Merger Limited (“Merger”) Lucid Markets Trading Limited (“Lucid”) Lucid Markets LLP (“Lucid LLP”) Faros Trading LLC* (“Faros”) V3 Markets, LLC (“V3”) * Sold by the Company in April 2015 ** Sold by the Company in September 2015 *** Sold by the Company in December 2015 Net income or loss attributable to the non-controlling interest in Holdings in the condensed consolidated statements of operations represents the portion of earnings or loss attributable to the economic interest in Holdings held by the non-controlling unit holders. Net income or loss attributable to other non-controlling interests in the condensed consolidated statements of operations represents the portion of net income or loss attributable to the non-controlling interests of Lucid, Faros (prior to the sale of Faros' operations in the second quarter of 2015), V3 and other consolidated entities. Net income or loss attributable to the non-controlling interest in Lucid represents the portion of earnings or loss attributable to the 49.9% economic interest held by Lucid non-controlling members whose allocation among the non-controlling members is not contingent upon services being provided. The portion of the 49.9% of Lucid earnings allocated among the non-controlling members of Lucid contingent on services provided is reported as a component of compensation expense and is included in the determination of Income (loss) from discontinued operations, net of tax in the condensed consolidated statements of operations (see Note 4). Net income or loss attributable to the non-controlling interests in Faros and V3 represents the portion of earnings or loss attributable to the 49.9% economic interests held by the non-controlling members of Faros (prior to the sale of Faros' operations in the second quarter of 2015) and V3. Net income or loss attributable to the non-controlling interests in other consolidated entities represents the portion of earnings or loss attributable to the economic interests held by the non-controlling members. Non-controlling interests in the condensed consolidated statements of financial condition represent the portion of equity attributable to the non-controlling interests of Holdings, Lucid, V3 and other consolidated entities. The allocation of equity to the non-controlling interests is based on the percentage owned by the non-controlling interest in the respective entity. The Company no longer holds its controlling interest in Faros as a result of the sale of Faros' operations in the second quarter of 2015. Investments where the Company is deemed to exercise significant influence, but no control, are accounted for using the equity method of accounting. The Company records its pro-rata share of earnings or losses each period and records any dividends as a reduction in the investment balance. The carrying value of these investments is included in Other assets in the condensed consolidated statements of financial condition and earnings or losses are included in Income or loss on equity method investments, net in the condensed consolidated statements of operations. For the Company's equity method investments classified as discontinued operations, the carrying value of the investments is included in assets held for sale on the condensed consolidated statements of financial condition and earnings or losses are included in the determination of Income or loss from discontinued operations, net of tax in the condensed consolidated statements of operations (see Note 6).
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions 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 as well as the reported amount of revenue and expenses during the year. Actual results could differ from those estimates and could have a material impact on the condensed consolidated financial statements.
Reclassifications	Reclassifications Certain reclassifications of prior period amounts related to the Company's retrospective adoption of Accounting Standards Update (“ASU”) No. 2015-03, Interest—Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs , have been made to conform to the current period's presentation in the condensed consolidated statements of financial condition (see Note 2).
Accounting Pronouncements Adopted in 2016 and Recently Issued Accounting Pronouncements	Accounting Pronouncements Adopted in 2016 In April 2015, the FASB issued ASU No. 2015-03, Interest—Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs . ASU No. 2015-03 requires debt issuance costs to be presented in the balance sheet as a direct deduction from the corresponding debt liability rather than as an asset. The costs will continue to be amortized and reported as interest expense. The Company adopted ASU No. 2015-03 on January 1, 2016 on a retrospective basis. The adoption of ASU No. 2015-03 resulted in the reclassification of $2.9 million of unamortized debt issuance costs as of December 31, 2015 related to the Company's Senior convertible notes from Other assets, as previously reported, to the Senior convertible notes liability within the condensed consolidated statements of financial condition (see Note 13). The adoption of ASU No. 2015-03 also resulted in the reclassification of $0.5 million of unamortized debt issuance costs as of December 31, 2015 related to the Company's Credit Agreement from Other assets, as previously reported, to the Credit Agreement liability within the condensed consolidated statements of financial condition (see Note 12). Other than these reclassifications, the adoption of ASU No. 2015-03 did not have an impact on the Company's condensed consolidated financial statements. In February 2015, the FASB issued ASU No. 2015-02, Consolidation (Topic 810): Amendments to the Consolidation Analysis . ASU No. 2015-02 changes the analysis that a reporting entity must perform to determine whether it should consolidate certain types of legal entities. Specifically, ASU No. 2015-02 (i) modifies the evaluation of whether limited partnership and similar legal entities are VIEs, (ii) eliminates the presumption that a general partner should consolidate a limited partnership, (iii) affects the consolidation analysis of reporting entities that are involved with VIEs that have fee arrangements and related party relationships, and (iv) provides a scope exception from consolidation guidance for certain investment companies and similar entities. The Company adopted ASU No. 2015-02 on January 1, 2016 which did not have an impact on the Company's condensed consolidated financial statements. Recently Issued Accounting Pronouncements In January 2016, the FASB issued ASU No. 2016-01, Financial Instruments—Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities . This guidance in this update amends various aspects of the recognition, measurement, presentation, and disclosure for financial instruments. The guidance in this update is effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. Early adoption by public entities is permitted only for certain provisions. The adoption of this standard may result in a cumulative-effect adjustment to the consolidated statement of financial condition as of the beginning of the year of adoption. The Company expects to adopt this guidance beginning January 1, 2018 and is currently evaluating the impact that adoption of this standard will have on its consolidated financial statements. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) . ASU No. 2016-02 requires lessees to recognize, on the balance sheet, assets and liabilities for the rights and obligations created by leases classified as operating leases of greater than twelve months. The accounting by lessors will remain largely unchanged. The guidance in this update is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, with early adoption permitted. The new standard must be adopted using a modified retrospective approach, and provides for certain practical expedients. Transition will require application of the new guidance at the beginning of the earliest period presented. The Company expects to adopt this guidance beginning January 1, 2019 and is currently evaluating the impact that adoption of this standard will have on its consolidated financial statements. In March 2016, the FASB issued ASU No. 2016-06, Derivatives and Hedging (Topic 815): Contingent Put and Call Options in Debt Instruments . ASU No. 2016-06 clarifies the requirements for assessing whether contingent call (put) options that can accelerate the payment of principal on debt instruments are clearly and closely related to their debt hosts. An entity performing the assessment under the amendments in this update is required to assess the embedded call (put) options solely in accordance with the four-step decision sequence in ASC 815-15-25-42. The guidance in this update is effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. Early adoption is permitted. An entity should apply the amendments in this update on a modified retrospective basis to existing debt instruments as of the beginning of the fiscal year for which the amendments are effective. The Company expects to adopt this guidance beginning January 1, 2017 and is currently evaluating the impact that adoption of this standard will have on its consolidated financial statements. In March 2016, the FASB issued ASU No. 2016-07, Investments—Equity Method and Joint Ventures (Topic 323): Simplifying the Transition to the Equity Method of Accounting . ASU No. 2016-07 eliminates the requirement that an investor retrospectively apply equity method accounting when an investment that it had accounted for by another method initially qualifies for the equity method. The guidance requires that an equity method investor add the cost of acquiring the additional interest in the investee to the current basis of the investor’s previously held interest and adopt the equity method of accounting as of the date the investment becomes qualified for equity method accounting. The guidance in this update is effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. Earlier application is permitted. The Company expects to adopt this guidance beginning January 1, 2017 and does not currently expect it will have a material impact on its consolidated financial statements. In March 2016, the FASB issued ASU No. 2016-09, Compensation—Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting . ASU No. 2016-09 simplifies certain aspects related to the accounting for share-based payment transactions, including income tax consequences, statutory withholding requirements, forfeitures and classification on the statement of cash flows. The guidance in this update is effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. Early adoption is permitted. Certain of the amendments related to timing of the recognition of tax benefits and tax withholding requirements should be applied using a modified retrospective transition method. Amendments related to classification on the statement of cash flows should be applied retrospectively. All other provisions may be applied on a prospective or modified retrospective basis. The Company expects to adopt this guidance beginning January 1, 2017 and is currently evaluating the impact that adoption of this standard will have on its consolidated financial statements. In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) . The guidance in this update supersedes nearly all existing revenue recognition guidance under U.S. GAAP and creates a single, principle-based revenue recognition framework that is codified in a new FASB ASC Topic 606. The new revenue standard establishes principles for recognizing revenue to depict the transfer of goods or services to customers at an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods or services and allows for either the full retrospective or cumulative effect transition method of adoption. In August 2015, the FASB issued ASU No. 2015-14, Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date, which deferred the effective date of the new revenue standard by one year. The new effective date is for annual reporting periods beginning after December 15, 2017, and interim periods within those years. Early adoption is permitted for annual reporting periods beginning after December 15, 2016, including interim periods within that year. In March 2016, the FASB issued ASU No. 2016-08, Revenue from Contracts with Customers (Topic 606): Principal versus Agent Considerations (Reporting Revenue Gross versus Net) , an amendment to the guidance in ASU No. 2014-09 that clarifies how an entity should identify the unit of accounting for the principal versus agent evaluation and how it should apply the control principle to certain types of arrangements, such as service transactions. The amendments also reframe the indicators to focus on a principal rather than an agent and eliminated two of the indicators (“the entity’s consideration is in the form of a commission” and “the entity is not exposed to credit risk”). This amendment also clarifies that each indicator may be more or less relevant to the assessment depending on the terms and conditions of the contract. In April 2016, the FASB issued ASU No. 2016-10, Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing, an amendment to the guidance in ASU No. 2014-09 which clarifies the following two aspects of Topic 606: (a) identifying performance obligations and (b) the licensing implementation guidance. The amendments do not change the core principle of the guidance in Topic 606. In May 2016, the FASB issued ASU No. 2016-12, Revenue from Contracts with Customers (Topic 606): Narrow-Scope Improvements and Practical Expedients . ASU No. 2016-12, among other things: (1) clarifies the objective of the collectibility criterion for applying paragraph 606-10-25-7; (2) permits an entity to exclude amounts collected from customers for all sales (and other similar) taxes from the transaction price; (3) specifies that the measurement date for noncash consideration is contract inception; (4) provides a practical expedient that permits an entity to reflect the aggregate effect of all modifications that occur before the beginning of the earliest period presented when identifying the satisfied and unsatisfied performance obligations, determining the transaction price, and allocating the transaction price to the satisfied and unsatisfied performance obligations; (5) clarifies that a completed contract for purposes of transition is a contract for which all (or substantially all) of the revenue was recognized under legacy GAAP before the date of initial application, and (6) clarifies that an entity that retrospectively applies the guidance in Topic 606 to each prior reporting period is not required to disclose the effect of the accounting change for the period of adoption. The amendments do not change the core principle of the guidance in Topic 606. The effective date and transition requirements for the Topic 606 amendments are the same as the effective date and transition requirements in Topic 606. The updated standard is effective for the Company's first quarter of 2018. The Company is currently evaluating the impact of this guidance on its consolidated financial statements and has not yet selected a transition method.

Description of Business and B30

Description of Business and Basis of Presentation (Tables)	6 Months Ended
	Jun. 30, 2016
Accounting Policies [Abstract]
Schedule of significant subsidiaries	The Company’s condensed consolidated financial statements include the following significant subsidiaries of Holdings: FXCM Newco, LLC (“Newco”) FXCM Global Services, LLC (“Global Services”) Forex Capital Markets LLC (“US”) FXCM Asia Limited** (“HK”) Forex Capital Markets Limited (“UK LTD”) FXCM Australia Pty. Limited (“Australia”) ODL Group Limited (“ODL”) FXCM Securities Limited*** (“FSL”) FXCM Japan Securities Co., Ltd.* (“FXCMJ”) FXCM UK Merger Limited (“Merger”) Lucid Markets Trading Limited (“Lucid”) Lucid Markets LLP (“Lucid LLP”) Faros Trading LLC* (“Faros”) V3 Markets, LLC (“V3”) * Sold by the Company in April 2015 ** Sold by the Company in September 2015 *** Sold by the Company in December 2015

Non-Controlling Interests (Tabl

Non-Controlling Interests (Tables)	6 Months Ended
	Jun. 30, 2016
Noncontrolling Interest [Abstract]
Changes in the non-controlling and the corporation's interest in Holdings	There were no changes in the non-controlling and the Corporation's interests in Holdings for the six months ended June 30, 2016 : Controlling Non- Total FXCM Inc. Non- Total Balance as of January 1, 2016 5,602,534 2,637,089 8,239,623 67.9 % 32.1 % 100 % Holdings Units acquired by FXCM Inc. related to exchanges of Holdings Units for shares of Class A common stock — — — — % — % — % Balance as of June 30, 2016 5,602,534 2,637,089 8,239,623 67.9 % 32.1 % 100.0 %

Discontinued Operations (Tables

Discontinued Operations (Tables)	6 Months Ended
	Jun. 30, 2016
Discontinued Operations and Disposal Groups [Abstract]
Schedule of disposal groups, including discontinued operations, effect on income statement and balance sheet	The following table presents the major classes of line items constituting the pretax and after-tax profit or loss of discontinued operations for the three and six months ended June 30, 2016 and 2015 , with amounts in thousands: Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 Revenues Trading revenue $ 7,468 $ 20,486 $ 13,804 $ 46,768 Interest income 10 31 139 218 Brokerage interest expense — (36 ) — (71 ) Net interest revenue 10 (5 ) 139 147 Other income 24 977 24 3,372 Total net revenues 7,502 21,458 13,967 50,287 Operating Expenses Compensation and benefits 472 3,766 513 10,801 Allocation of net income to Lucid members for services provided 1,360 1,981 2,561 4,667 Total compensation and benefits 1,832 5,747 3,074 15,468 Referring broker fees — — — 208 Advertising and marketing — 209 — 721 Communication and technology 1,426 2,180 2,923 4,467 Trading costs, prime brokerage and clearing fees 3,099 4,790 6,709 10,538 General and administrative 1,117 1,242 1,622 3,237 Bad debt expense — — — 8,408 Depreciation and amortization — — — 12,359 Goodwill impairment loss — — — 54,865 Total operating expenses 7,474 14,168 14,328 110,271 Operating income (loss) 28 7,290 (361 ) (59,984 ) Other (Expense) Income (Loss) income on equity method investments, net (60 ) (576 ) 93 (501 ) Gain on disposition of equity method investment (see Note 6) — — 679 — (Loss) income from discontinued operations before income taxes (32 ) 6,714 411 (60,485 ) Gain on completed dispositions — 1,978 — 1,978 Loss on classification as held for sale before income taxes (486 ) (2,300 ) (31,997 ) (28,799 ) Total (loss) income from discontinued operations before income taxes * (518 ) 6,392 (31,586 ) (87,306 ) Income tax provision — 727 — 5,627 (Loss) income from discontinued operations, net of tax $ (518 ) $ 5,665 $ (31,586 ) $ (92,933 ) * Total (loss) income from discontinued operations before income taxes attributable to FXCM Inc. was $(0.1) million and $(11.6) million for the three and six months ended June 30, 2016 , respectively, and $1.6 million and $(28.9) million for the three and six months ended June 30, 2015 , respectively. The following is a summary of the carrying amounts of the assets and liabilities included as part of discontinued operations as of June 30, 2016 and December 31, 2015 , with amounts in thousands: As of June 30, 2016 December 31, 2015 Assets Cash and cash equivalents $ 13,471 $ 10,786 Due from brokers (1) 18,550 22,234 Accounts receivable, net 113 178 Office, communication and computer equipment, net 1,274 1,154 Goodwill 223,613 223,613 Other intangible assets, net 27,269 27,269 Other assets (2) (3) 14,097 15,363 Loss recognized on classification as held for sale (98,657 ) (66,660 ) Total assets classified as held for sale on the condensed consolidated statements of financial condition $ 199,730 $ 233,937 Liabilities Accounts payable and accrued expenses (4) $ 9,505 $ 10,838 Due to brokers (1) 256 — Securities sold, not yet purchased 3,896 3,624 Other liabilities 33 48 Total liabilities classified as held for sale on the condensed consolidated statements of financial condition $ 13,690 $ 14,510 ____________________________________ (1) Includes as of June 30, 2016 and December 31, 2015 : a) derivative assets, net of $2.8 million and $0.9 million , respectively; b) Unsettled spot FX net asset of $0.1 million and $0.3 million , respectively; c) Unsettled common stock of $3.0 million and $3.0 million , respectively; and d) Excess cash collateral of $12.6 million and $18.0 million , respectively. (2) Includes the Company's exchange memberships, which represent ownership interests and shares owned in CME Group Inc. and provide the Company with the right to conduct business on the exchange. The exchange memberships are recorded at cost or, if an other-than-temporary impairment in value has occurred, at a value that reflects management's estimate of the impairment. The Company had previously owned shares in the Intercontinental Exchange which were sold in April 2015. The Company recognized a gain of $0.1 million related to the sale which was recorded in earnings as a component of Income (loss) from discontinued operations, net of tax during the second quarter of 2015. In the fourth quarter of 2015, the Company acquired additional ownership interests and shares in CME Group Inc. from one of the non-controlling members of Lucid which were recorded at a total cost of $3.7 million . There were no exchange membership impairments as of June 30, 2016 or December 31, 2015 . As of both June 30, 2016 and December 31, 2015 , the carrying value of ownership interests was $4.6 million and the carrying value of shares owned was $4.8 million . (3) Includes the carrying value of the Company's equity interest in FastMatch of $4.2 million as of both June 30, 2016 and December 31, 2015 . The carrying value of the Company's previously-held equity interest in the V3-related LLC of $1.5 million is included in the balance as of December 31, 2015 (see Note 6). (4) Includes as of June 30, 2016 and December 31, 2015 amounts due related to the allocation of income to Lucid non-controlling members for services provided of $5.7 million and $6.5 million , respectively.

Goodwill (Tables)

Goodwill (Tables)	6 Months Ended
	Jun. 30, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of changes in goodwill	Changes in goodwill for the six months ended June 30, 2016 are presented in the following table and reflect the Company's single operating segment, with amounts in thousands: Balance as of January 1, 2016 $ 28,080 Foreign currency translation adjustments (2,717 ) Balance as of June 30, 2016 $ 25,363

Other Intangible Assets, net (T

Other Intangible Assets, net (Tables)	6 Months Ended
	Jun. 30, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of finite-lived intangible assets	The Company’s intangible assets consisted of the following as of June 30, 2016 and December 31, 2015 , with amounts in thousands: June 30, 2016 December 31, 2015 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Finite-lived intangible assets Customer relationships $ 35,460 $ (24,259 ) $ 11,201 $ 35,460 $ (21,223 ) $ 14,237 Foreign currency translation adjustment (3,630 ) 1,499 (2,131 ) (1,910 ) 855 (1,055 ) Total finite-lived intangible assets 31,830 (22,760 ) 9,070 33,550 (20,368 ) 13,182 Indefinite-lived intangible assets License 600 — 600 600 — 600 Total Other intangible assets, net $ 32,430 $ (22,760 ) $ 9,670 $ 34,150 $ (20,368 ) $ 13,782
Schedule of indefinite-lived intangible assets	The Company’s intangible assets consisted of the following as of June 30, 2016 and December 31, 2015 , with amounts in thousands: June 30, 2016 December 31, 2015 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Finite-lived intangible assets Customer relationships $ 35,460 $ (24,259 ) $ 11,201 $ 35,460 $ (21,223 ) $ 14,237 Foreign currency translation adjustment (3,630 ) 1,499 (2,131 ) (1,910 ) 855 (1,055 ) Total finite-lived intangible assets 31,830 (22,760 ) 9,070 33,550 (20,368 ) 13,182 Indefinite-lived intangible assets License 600 — 600 600 — 600 Total Other intangible assets, net $ 32,430 $ (22,760 ) $ 9,670 $ 34,150 $ (20,368 ) $ 13,782
Schedule of estimated future amortization expense for intangible assets	Estimated future amortization expense for intangible assets outstanding as of June 30, 2016 is as follows, with amounts in thousands: Year Ending December 31, Remainder of 2016 $ 3,273 2017 4,039 2018 1,433 2019 325 2020 — Thereafter — $ 9,070

Earnings per Share (Tables)

Earnings per Share (Tables)	6 Months Ended
	Jun. 30, 2016
Earnings Per Share [Abstract]
Reconciliation of numerator and denominator used in basic and diluted EPS calculations	The following is a reconciliation of the numerator and denominator used in the basic and diluted EPS calculations, with amounts in thousands except per share data: Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 Basic and diluted net income (loss) per share of Class A common stock: Numerator Income (loss) from continuing operations attributable to FXCM Inc. $ 60,495 $ (98,886 ) $ 121,765 $ (492,211 ) (Loss) income from discontinued operations attributable to FXCM Inc. (94 ) 3,075 (11,629 ) (30,417 ) Net income (loss) available to holders of Class A common stock 60,401 (95,811 ) 110,136 (522,628 ) Earnings allocated to participating securities — — — — Income (loss) available to common stockholders $ 60,401 $ (95,811 ) $ 110,136 $ (522,628 ) Denominator Weighted average shares of Class A common stock (1) 5,603 4,871 5,603 4,790 Add dilutive effect of the following: Stock options and RSUs (1),(2) — — — Convertible note hedges — — — Warrants — — — — Assumed conversion of Holdings Units for Class A common stock — — — — Dilutive weighted average shares of Class A common stock (1) 5,603 4,871 5,603 4,790 Net income (loss) per share of Class A common stock — Basic and Diluted (1) : Continuing operations $ 10.80 $ (20.30 ) $ 21.73 $ (102.76 ) Discontinued operations (0.02 ) 0.63 (2.08 ) (6.35 ) Net income (loss) per share of Class A common stock $ 10.78 $ (19.67 ) $ 19.65 $ (109.11 ) ____________________________________ (1) Prior periods are adjusted to reflect the impact of the one-for-ten reverse stock split that became effective on October 1, 2015. (2) No dilutive effect for the three and six months ended June 30, 2016 therefore zero incremental shares included for the period.

Related Party Transactions (Tab

Related Party Transactions (Tables)	6 Months Ended
	Jun. 30, 2016
Related Party Transactions [Abstract]
Amounts receivable from, and payable to, related parties	Amounts receivable from, and payable to, related parties are set forth below, with amounts in thousands: As of June 30, 2016 December 31, 2015 Receivables Advances to Holdings non-controlling members $ 505 $ 112 Accounts receivable — Lucid non-controlling members 15 15 Advances to employees 33 201 Notes receivable and interest — Lucid non-controlling members — 8,171 Total receivables from related parties $ 553 $ 8,499 Payables Employees $ 530 $ 1,104 Due to Lucid non-controlling members in connection with the allocation of income to Lucid non-controlling members for services provided 5,715 6,500 Tax receivable agreement — 145 Total payables to related parties $ 6,245 $ 7,749

Net Capital Requirements (Table

Net Capital Requirements (Tables)	6 Months Ended
	Jun. 30, 2016
Banking and Thrift [Abstract]
Schedule of minimum capital requirement and the excess capital	The tables below present the capital, as defined by the respective regulatory authority, the minimum capital requirement and the excess capital for the following regulated entities as of June 30, 2016 and December 31, 2015 , with amounts in millions: As of June 30, 2016 US UK LTD Australia Lucid LLP Capital $ 53.2 $ 84.9 $ 12.3 $ 11.7 Minimum capital requirement 34.2 21.3 0.7 4.8 Excess capital $ 19.0 $ 63.6 $ 11.6 $ 6.9 As of December 31, 2015 US UK LTD Australia Lucid LLP Capital $ 43.6 $ 76.3 $ 12.0 $ 10.9 Minimum capital requirement 28.3 27.6 0.7 4.0 Excess capital $ 15.3 $ 48.7 $ 11.3 $ 6.9

Leucadia Transaction (Tables)

Leucadia Transaction (Tables)	6 Months Ended
	Jun. 30, 2016
Extraordinary and Unusual Items [Abstract]
Schedule of allocation of net proceeds from letter agreement	Leucadia will own a non-voting preferred class of membership interest that, when added to its 49.9% common membership interest, will result in the following distribution of proceeds from FXCM Group: Aggregate amount of proceeds Original Waterfall Revised Waterfall Amounts due under the Credit Agreement 100% Leucadia 100% Leucadia Next $350 million 50% Leucadia / 50% FXCM 45% Leucadia / 45% FXCM / 10.0% FXCM management Next $500 million 90% Leucadia / 10% FXCM 79.2% Leucadia / 8.8% FXCM / 12.0% FXCM management All aggregate amounts thereafter 60% Leucadia / 40% FXCM 51.6% Leucadia / 34.4% FXCM / 14.0% FXCM management The Letter Agreement allocates net proceeds as follows: Aggregate amount of proceeds Leucadia FXCM Holdings Amounts due under Leucadia term loan, including fees 100% 0% Next $350 million 50% 50% Next $500 million * 90% 10% All aggregate amounts thereafter 60% 40% * Per the Letter Agreement, this amount was initially set at a range of $500 million to $680 million . As a result of the prepayments made by the Company through April 16, 2015, this amount is $500 million .
Schedule of balance of credit agreement	The balance of the Credit Agreement as of June 30, 2016 and December 31, 2015 , was as follows, with amounts in thousands: As of June 30, 2016 December 31, 2015 Debt principal $ 192,543 $ 192,685 Original issue discount (18,898 ) (35,967 ) Discount — issuance fee (2,837 ) (5,227 ) Deferred financing fee (2,042 ) (3,762 ) Debt issuance costs (253 ) (467 ) Embedded derivative — Mandatory prepayment provision 11,640 — Debt — net carrying value $ 180,153 $ 147,262
Schedule of interest expense	Interest expense related to the Credit Agreement, included in Interest on borrowings in the condensed consolidated statements of operations for the three and six months ended June 30, 2016 and 2015 , consists of the following, with amounts in thousands: Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 Contractual interest $ 8,406 $ 6,653 $ 16,092 $ 12,901 Deferred interest (967 ) 2,168 (1,210 ) 4,852 Amortization of original issue discount 8,762 26,411 17,070 40,687 Amortization of issuance fee discount 1,248 3,539 2,390 5,318 Amortization of deferred financing fee 898 2,548 1,720 3,828 Amortization of debt issuance costs 111 316 213 475 Total interest expense — Credit Agreement $ 18,458 $ 41,635 $ 36,275 $ 68,061

Debt (Tables)

Debt (Tables)	6 Months Ended
	Jun. 30, 2016
Debt Disclosure [Abstract]
Balance of liability and equity components of convertible debt	The balances of the liability and equity components as of June 30, 2016 and December 31, 2015 , were as follows, with amounts in thousands: As of June 30, 2016 December 31, 2015 Liability component — principal $ 172,500 $ 172,500 Deferred bond discount (12,380 ) (15,315 ) Deferred debt issuance costs (2,325 ) (2,930 ) Liability component — net carrying value $ 157,795 $ 154,255 Equity component $ 29,101 $ 29,101 Interest expense related to the Convertible Notes, included in Interest on borrowings in the condensed consolidated statements of operations, consists of the following, with amounts in thousands: Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 Stated coupon rate $ 971 $ 970 $ 1,941 $ 1,941 Amortization of deferred bond discount 1,471 1,384 2,935 2,761 Amortization of debt issuance cost 302 302 604 605 Total interest expense — Convertible Notes $ 2,744 $ 2,656 $ 5,480 $ 5,307

Derivative Financial Instrume40

Derivative Financial Instruments (Tables)	6 Months Ended
	Jun. 30, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of derivative assets and liabilities net of counterparty and collateral offsets	The following tables present the gross and net fair values of the Company's derivative transactions and the related offsetting amount permitted under ASC 210 and ASC 815 as of June 30, 2016 and December 31, 2015 . Derivative assets and liabilities are net of counterparty and collateral offsets. Collateral offsets include cash margin amounts posted with brokers. Under ASC 210, gross positive fair values are offset against gross negative fair values by counterparty pursuant to enforceable master netting agreements, with amounts in thousands: As of June 30, 2016 Derivative Assets Derivative Liabilities Statement of Financial Condition Location Fair Value Notional Fair Value Notional Exchange traded options Current assets/liabilities held for sale (1) $ 9,907 $ 30,007 $ — $ — CFD contracts Due from/Due to brokers (2) 2 1,863 — — Futures contracts Due from/Due to brokers and Current assets/liabilities held for sale (1), (2) 720 39,839 19,920 1,754,330 OTC options Current assets/liabilities held for sale (1) 1,255 74,245 1,511 69,024 Total derivatives, gross $ 11,884 $ 145,954 $ 21,431 $ 1,823,354 Netting agreements and cash collateral netting (9,037 ) (9,037 ) Total derivatives, net $ 2,847 $ 12,394 ____________________________________ (1) As of June 30, 2016 , the aggregate fair values of derivative assets and liabilities, gross attributable to discontinued operations is $11.6 million and $9.0 million , respectively. These amounts are offset by netting agreements and cash collateral netting of $8.8 million and $8.8 million , respectively. (2) As of June 30, 2016 , the aggregate fair values of derivative assets and liabilities, gross attributable to continuing operations is $0.3 million and $12.4 million , respectively. These amounts are offset by netting agreements and cash collateral netting of $0.3 million and $0.3 million , respectively. As of December 31, 2015 Derivative Assets Derivative Liabilities Statement of Financial Condition Location Fair Value Notional Fair Value Notional Exchange traded options Current assets/liabilities held for sale (3) $ 6,503 $ 15,399 $ 5,805 $ 18,282 CFD contracts Due from/Due to brokers (4) 206 109,715 36 99,036 Futures contracts Due from/Due to brokers and Current assets/liabilities held for sale (3), (4) 4,212 794,960 3,102 1,047,239 Total derivatives, gross $ 10,921 $ 920,074 $ 8,943 $ 1,164,557 Netting agreements and cash collateral netting (8,909 ) (8,909 ) Total derivatives, net $ 2,012 $ 34 ____________________________________ (3) As of December 31, 2015 , the aggregate fair values of derivative assets and liabilities, gross attributable to discontinued operations is $9.7 million and $8.8 million , respectively. These amounts are offset by netting agreements and cash collateral netting of $8.8 million and $8.8 million , respectively. (4) As of December 31, 2015 , the aggregate fair value of derivative assets and liabilities, gross attributable to continuing operations is $1.2 million and $0.1 million , respectively. These amounts are offset by netting agreements and cash collateral netting of $0.1 million and $0.1 million , respectively.
Schedule of gains (losses) on derivative instruments	The following table presents the gains (losses) on derivative instruments recognized in the condensed consolidated statements of operations for the three and six months ended June 30, 2016 and 2015 , with amounts in thousands: Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 Exchange traded options (5) $ 737 $ 1,176 $ 11,091 $ (729 ) CFD contracts (6) (1,305 ) 415 (1,445 ) (5,347 ) Futures contracts (7) (15,736 ) 18,000 (30,856 ) 38,062 OTC options (5) (10 ) — 2 1,086 Total $ (16,314 ) $ 19,591 $ (21,208 ) $ 33,072 ____________________________________ (5) Included in Income (loss) from discontinued operations, net of tax in the condensed consolidated statements of operations for all periods presented. (6) Included in Trading revenue in the condensed consolidated statements of operations for all periods presented. (7) The portion included in Income (loss) from continuing operations in the condensed consolidated statements of operations is $(17.7) million and $(25.3) million for the three and six months ended June 30, 2016 , respectively, and $11.1 million and $18.3 million for the three and six months ended June 30, 2015 , respectively.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2016
Fair Value Disclosures [Abstract]
Schedule of assets and liabilities that are measured at fair value on a recurring basis	The following tables present the Company's assets and liabilities that are measured at fair value on a recurring basis and the related hierarchy levels, with amounts in thousands: Fair Value Measurements on a Recurring Basis As of June 30, 2016 Level 1 Level 2 Level 3 Counterparty and Cash Collateral Netting Total Financial Assets: Derivative assets: Exchange traded options $ 9,907 $ — $ — $ — $ 9,907 CFD contracts — 2 — — 2 Futures contracts 720 — — — 720 OTC options — 1,255 — — 1,255 Netting — — — (9,037 ) (9,037 ) Total derivative assets (1) 10,627 1,257 — (9,037 ) 2,847 Total assets $ 10,627 $ 1,257 $ — $ (9,037 ) $ 2,847 Financial Liabilities: Customer account liabilities $ — $ 662,392 $ — $ — $ 662,392 Derivative liabilities: Futures contracts 19,920 — — — 19,920 OTC options — 1,511 — — 1,511 Netting — — — (9,037 ) (9,037 ) Total derivative liabilities (1) 19,920 1,511 — (9,037 ) 12,394 Securities sold, not yet purchased (2) 3,896 — — — 3,896 Letter Agreement — — 209,458 — 209,458 Mandatory Prepayment Provision — Credit Agreement — — 11,640 — 11,640 Total liabilities $ 23,816 $ 663,903 $ 221,098 $ (9,037 ) $ 899,780 As of June 30, 2016 , the Company's total notional absolute value of open FX and CFD customer assets and liabilities by currency pair or product was $1.4 billion and $1.8 billion , respectively. The Company's total net notional value for open FX and CFD positions was $1.5 billion . Fair Value Measurements on a Recurring Basis As of December 31, 2015 Level 1 Level 2 Level 3 Counterparty and Cash Collateral Netting Total Financial Assets: Derivative assets: Exchange traded options $ 6,503 $ — $ — $ — $ 6,503 CFD contracts — 206 — — 206 Futures contracts 4,212 — — — 4,212 Netting — — — (8,909 ) (8,909 ) Total derivative assets (1) 10,715 206 — (8,909 ) 2,012 Total assets $ 10,715 $ 206 $ — $ (8,909 ) $ 2,012 Financial Liabilities: Customer account liabilities $ — $ 685,043 $ — $ — $ 685,043 Derivative liabilities: Exchange traded options 5,805 — — — 5,805 CFD contracts — 36 — — 36 Futures contracts 3,102 — — — 3,102 Netting — — — (8,909 ) (8,909 ) Total derivative liabilities (1) 8,907 36 — (8,909 ) 34 Securities sold, not yet purchased (2) 3,624 — — — 3,624 Letter Agreement — — 448,458 — 448,458 Total liabilities $ 12,531 $ 685,079 $ 448,458 $ (8,909 ) $ 1,137,159 As of December 31, 2015 , the Company's total notional absolute value of open FX and CFD customer assets and liabilities by currency pair or product was $2.5 billion and $2.5 billion , respectively. The Company's total net notional value for open FX and CFD positions was $2.2 billion . ____________________________________ (1) Attributable to continuing and discontinued operations. See Note 15 for details of the classification of amounts on the condensed consolidated statements of financial condition. (2) Attributable to discontinued operations. Amounts classified as held for sale on the condensed consolidated statements of financial condition (see Note 4).
Summary of significant Level 3 fair value inputs	The significant Level 3 inputs are considered more relevant in the analysis and are given a higher weighting in the overall fair value determination (see Note 12). The following table summarizes the significant Level 3 inputs used in the fair value determination of the Letter Agreement as of June 30, 2016 and December 31, 2015 , respectively: As of Valuation Technique Significant Unobservable Inputs June 30, 2016 December 31, 2015 Option-Pricing Method Term (years) 2.0 2.5 Volatility 133.6 % 79.1 % Risk-free rate 0.6 % 1.2 % Dividend yield — % — % Reliance placed on public indication of value 100.0 % 100.0 %
Schedule of carrying value, fair value, and fair value hierarchy category	The following tables present the carrying value, fair value and fair value hierarchy category of certain financial instruments that are not measured at fair value in the condensed consolidated statements of financial condition, with amounts in thousands: As of June 30, 2016 Fair Value Measurements using: Carrying Value Fair Value Level 1 Level 2 Level 3 Financial Assets: Due from brokers — unsettled spot FX (4) $ 2,161 $ 2,161 $ — $ 2,161 $ — Due from brokers — unsettled common stock (5) 3,054 3,054 — 3,054 — Due from brokers — excess cash collateral (5) 12,559 12,559 — 12,559 — Equity method investments (4) 6,505 12,800 — — 12,800 Cost method investment 1,103 1,103 — — 1,103 Exchange memberships (5) 9,434 9,249 — 9,249 — Total assets $ 34,816 $ 40,926 $ — $ 27,023 $ 13,903 Financial Liabilities: Due to brokers — unsettled spot FX (4) $ 38 $ 38 $ — $ 38 $ — Senior convertible notes 157,795 59,944 — 59,944 — Credit Agreement 180,153 164,253 — — 164,253 Total liabilities $ 337,986 $ 224,235 $ — $ 59,982 $ 164,253 As of December 31, 2015 Fair Value Measurements using: Carrying Value Fair Value Level 1 Level 2 Level 3 Financial Assets: Due from brokers — unsettled spot FX (4) $ 2,939 $ 2,939 $ — $ 2,939 $ — Due from brokers — unsettled common stock (5) 3,054 3,054 — 3,054 — Due from brokers — excess cash collateral (5) 18,010 18,010 — 18,010 — Equity method investments (4) 8,273 19,043 — — 19,043 Notes receivable 7,881 7,881 — — 7,881 Exchange memberships (5) 9,434 8,655 — 8,655 — Total assets $ 49,591 $ 59,582 $ — $ 32,658 $ 26,924 Financial Liabilities: Due to brokers — unsettled spot FX (4) $ 1,039 $ 1,039 $ — $ 1,039 $ — Senior convertible notes 157,185 121,187 — 121,187 — Credit Agreement 147,729 192,685 — — 192,685 Total liabilities $ 305,953 $ 314,911 $ — $ 122,226 $ 192,685 ____________________________________ (4) Attributable to continuing and discontinued operations. See Note 4 for amounts classified as held for sale on the condensed consolidated statements of financial condition. (5) Attributable to discontinued operations and included in assets held for sale on the condensed consolidated statements of financial condition (see Note 4).
Schedule of opening and ending balances of recurring fair value measurement categorized as Level 3	The following tables reconcile the opening and ending balances of the recurring fair value measurements categorized as Level 3, which are included in the condensed consolidated statements of financial condition, and identifies the total gains and losses the Company recognized during the three and six months ended June 30, 2016 and 2015 , with amounts in thousands: Three Months Ended June 30, 2016 Balance as of Additions Net Unrealized Balance as of Letter Agreement $ 337,627 $ — $ (128,169 ) $ 209,458 Mandatory Prepayment Provision — Credit Agreement — 11,640 — 11,640 Total Level 3 liabilities $ 337,627 $ 11,640 $ (128,169 ) $ 221,098 Six Months Ended June 30, 2016 Balance as of Additions Net Unrealized Balance as of Letter Agreement $ 448,458 $ — $ (239,000 ) $ 209,458 Mandatory Prepayment Provision — Credit Agreement — 11,640 — 11,640 Total Level 3 liabilities $ 448,458 $ 11,640 $ (239,000 ) $ 221,098 Three Months Ended June 30, 2015 Balance as of Additions Net Unrealized Balance as of Letter Agreement $ 386,230 $ — $ 99,867 $ 486,097 Total Level 3 liabilities $ 386,230 $ — $ 99,867 $ 486,097 Six Months Ended June 30, 2015 Balance as of Additions Net Unrealized Balance as of Letter Agreement $ — $ 94,436 $ 391,661 $ 486,097 Total Level 3 liabilities $ — $ 94,436 $ 391,661 $ 486,097

Description of Business and B42

Description of Business and Basis of Presentation - Additional Information (Detail)	Oct. 01, 2015	Apr. 15, 2015	Jun. 30, 2016	Dec. 31, 2015
FXCM Holdings
Basis of Presentation [Line Items]
Ownership percentage by parent			67.90%	67.90%
Noncontrolling equity interest			32.10%	32.10%
Lucid Markets Trading Limited
Basis of Presentation [Line Items]
Noncontrolling equity interest			49.90%
Common Stock - Class A
Basis of Presentation [Line Items]
Reverse stock split (in shares)	0.1	0.1

Significant Accounting Polici43

Significant Accounting Policies and Estimates (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Credit Agreement
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Unamortized debt issuance cost	$ 253	$ 467
Accounting Standards Update 2015-03 | Senior Convertible Notes | Convertible Debt
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Unamortized debt issuance cost		2,900
Accounting Standards Update 2015-03 | Credit Agreement | Credit Agreement
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Unamortized debt issuance cost		$ 500

Non-Controlling Interests - Cha

Non-Controlling Interests - Change in Interest Holdings of Corporation and Non-Controlling Interest (Detail)	6 Months Ended
	Jun. 30, 2016shares
Controlling Units
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance (in shares)	5,602,534
Beginning balance (percent)	67.90%
Holding units acquired by FXCM Inc. related to exchanges of Holdings units for shares of Class A common stock (in shares)	0
Holdings units acquired by FXCM Inc. related to exchanges of Holdings units for shares of Class A common stock (percent)	0.00%
Ending balance (in shares)	5,602,534
Ending balance (percent)	67.90%
Non- controlling Interests
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance (in shares)	2,637,089
Beginning balance (percent)	32.10%
Holding units acquired by FXCM Inc. related to exchanges of Holdings units for shares of Class A common stock (in shares)	0
Holdings units acquired by FXCM Inc. related to exchanges of Holdings units for shares of Class A common stock (percent)	0.00%
Ending balance (in shares)	2,637,089
Ending balance (percent)	32.10%
Total Units
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance (in shares)	8,239,623
Beginning balance (percent)	100.00%
Holding units acquired by FXCM Inc. related to exchanges of Holdings units for shares of Class A common stock (in shares)	0
Holdings units acquired by FXCM Inc. related to exchanges of Holdings units for shares of Class A common stock (percent)	0.00%
Ending balance (in shares)	8,239,623
Ending balance (percent)	100.00%

Discontinued Operations - Addit

Discontinued Operations - Additional Information (Details) - USD ($)	1 Months Ended			3 Months Ended		6 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Apr. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Realization of cumulative translation adjustment				$ 0	$ 23,407,000	$ 0	$ 23,407,000
Deferred gain on disposal recognized in the period				100,000		300,000
FXCMJ
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration received for disposal group			$ 62,200,000
Gain (loss) on disposal of discontinued operations, net of tax			2,000,000
Realization of cumulative translation adjustment			23,400,000
Deferred gain on disposal from continuing services			$ 2,100,000
Deferred gain on disposal recognized in the period				500,000		1,200,000
Faros
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration received for disposal group				0	$ 0	0	$ 0
HK
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration received for disposal group		$ 37,900,000
Gain (loss) on disposal of discontinued operations, net of tax		12,400,000
Deferred gain on disposal from continuing services		$ 1,000,000
Deferred gain on disposal recognized in the period				$ 300,000		$ 600,000
FSL
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration received for disposal group	$ 2,300,000
Gain (loss) on disposal of discontinued operations, net of tax	(7,100,000)
Realization of cumulative translation adjustment	1,500,000
Deferred gain on disposal from continuing services	$ 500,000

Discontinued Operations - Incom

Discontinued Operations - Income Statement (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Revenues
Trading revenue	$ 7,468	$ 20,486	$ 13,804	$ 46,768
Interest income	10	31	139	218
Brokerage interest expense	0	(36)	0	(71)
Net interest revenue	10	(5)	139	147
Other income	24	977	24	3,372
Total net revenues	7,502	21,458	13,967	50,287
Operating Expenses
Compensation and benefits	472	3,766	513	10,801
Allocation of net income to Lucid members for services provided	1,360	1,981	2,561	4,667
Total compensation and benefits	1,832	5,747	3,074	15,468
Referring broker fees	0	0	0	208
Advertising and marketing	0	209	0	721
Communication and technology	1,426	2,180	2,923	4,467
Trading costs, prime brokerage and clearing fees	3,099	4,790	6,709	10,538
General and administrative	1,117	1,242	1,622	3,237
Bad debt expense	0	0	0	8,408
Depreciation and amortization	0	0	0	12,359
Goodwill impairment loss	0	0	0	54,865
Total operating expenses	7,474	14,168	14,328	110,271
Operating income (loss)	28	7,290	(361)	(59,984)
Other (Expense) Income
(Loss) income on equity method investments, net	(60)	(576)	93	(501)
Gain on disposition of equity method investment (see Note 6)	0	0	679	0
(Loss) income from discontinued operations before income taxes	(32)	6,714	411	(60,485)
Gain on completed dispositions	0	1,978	0	1,978
Loss on classification as held for sale before income taxes	(486)	(2,300)	(31,997)	(28,799)
Total (loss) income from discontinued operations before income taxes	(518)	6,392	(31,586)	(87,306)
Income tax provision	0	727	0	5,627
(Loss) income from discontinued operations, net of tax	(518)	5,665	(31,586)	(92,933)
Loss before income taxes, attributable to parent	$ (100)	$ 1,600	$ (11,600)	$ (28,900)

Discontinues Operations - Balan

Discontinues Operations - Balance Sheet (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2015	Jun. 30, 2016	Dec. 31, 2015
Assets
Cash and cash equivalents		$ 13,471	$ 10,786
Due from brokers		18,550	22,234
Accounts receivable, net		113	178
Office, communication and computer equipment, net		1,274	1,154
Goodwill		223,613	223,613
Other intangible assets, net		27,269	27,269
Other assets		14,097	15,363
Loss recognized on classification as held for sale		(98,657)	(66,660)
Total assets classified as held for sale on the condensed consolidated statements of financial condition		199,730	233,937
Liabilities
Accounts payable and accrued expenses		9,505	10,838
Due to brokers		256	0
Securities sold, not yet purchased		3,896	3,624
Other liabilities		33	48
Total liabilities classified as held for sale on the condensed consolidated statements of financial condition		13,690	14,510
Due from correspondent brokers, derivative assets, net		2,800	900
Due from correspondent brokers, unsettled spot foreign exchange liability, net		100
Due from correspondent brokers, unsettled spot foreign exchange asset, net			300
Due from correspondent brokers, unsettled common stock		3,000	3,000
Due from correspondent brokers, excess cash collateral		12,600	18,000
Other assets, exchange memberships, cost of ownership interests		4,600	4,600
Other assets, exchange memberships, cost of shares owned		4,800	4,800
Accounts payable and accrued liabilities, due to related party		5,700	6,500
Ownership Interest and Shares Owned
Liabilities
Memberships in exchanges owned		3,700	3,700
FastMatch Investment
Liabilities
Other assets, equity method investments		$ 4,200	4,200
V3-related LLC
Liabilities
Other assets, equity method investments			$ 1,500
International Exchanges
Liabilities
Gain on disposal of discontinued operations, net of tax	$ 100

Notes Receivable (Details)

Notes Receivable (Details) - Notes Receivable - Lucid Markets Trading Limited - USD ($) $ in Millions	1 Months Ended
	Jan. 31, 2014	Jun. 30, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable	$ 7.9
Related party notes receivable interest rate	2.00%
Allowance for notes		$ 8.2

Equity Method Investment - Addi

Equity Method Investment - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015	Jan. 31, 2014
Schedule of Equity Method Investments [Line Items]
Gain (loss) on equity method investments, net	$ (149)	$ (37)	$ (338)	$ (188)
Gain on disposition of equity method investment	0	0	679	0
Dividends from equity method investments	$ 0	0	$ 0	0
FX Trading Software Developer
Schedule of Equity Method Investments [Line Items]
Percentage of equity interest	22.10%		22.10%
FX Trading Software Developer | Loss on Equity Method Investments, Net
Schedule of Equity Method Investments [Line Items]
Gain (loss) on equity method investments, net	$ (100)	(37)	$ (300)	(200)
FX Trading Software Developer | Other Assets
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	2,300		2,300		$ 2,600
V3-related LLC
Schedule of Equity Method Investments [Line Items]
Percentage of equity interest					66.30%	66.30%
V3-related LLC | Loss from Discontinued Operations, Net of Tax
Schedule of Equity Method Investments [Line Items]
Gain on disposition of equity method investment			700
V3-related LLC | Other Assets
Schedule of Equity Method Investments [Line Items]
Cost method investments	1,100		1,100
Firm that Provides a Financial Intelligence Platform | V3-related LLC
Schedule of Equity Method Investments [Line Items]
Percentage of equity interest						17.26%
FastMatch and V3-related LLC | Loss from Discontinued Operations, Net of Tax
Schedule of Equity Method Investments [Line Items]
Gain (loss) on equity method investments, net	(100)	$ (600)	100	$ (500)
FastMatch and V3-related LLC | Assets Held-for-sale
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	$ 4,200		$ 4,200		$ 5,700

Goodwill (Details)

Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2016	Jun. 30, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill impairment loss	$ 0	$ 0	$ 9,500	$ 0	$ 9,513
Goodwill [Roll Forward]
Beginning balance				28,080
Foreign currency translation adjustments				(2,717)
Ending balance	$ 25,363			$ 25,363

Other Intangible Assets, net -

Other Intangible Assets, net - Schedule of Acquired Finite and Indefinite Lived Intangible Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Finite-lived intangible assets
Gross Carrying Amount	$ 31,830	$ 33,550
Accumulated Amortization	(22,760)	(20,368)
Net Carrying Amount	9,070	13,182
Indefinite-lived intangible assets
Intangible assets, gross (excluding goodwill)	32,430	34,150
Total intangible assets, net (excluding goodwill)	9,670	13,782
License
Indefinite-lived intangible assets
License	600	600
Customer relationships
Finite-lived intangible assets
Gross Carrying Amount	35,460	35,460
Accumulated Amortization	(24,259)	(21,223)
Net Carrying Amount	11,201	14,237
Foreign currency translation adjustment
Finite-lived intangible assets
Gross Carrying Amount	(3,630)	(1,910)
Accumulated Amortization	1,499	855
Net Carrying Amount	$ (2,131)	$ (1,055)

Other Intangible Assets, net 52

Other Intangible Assets, net - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Finite-Lived Intangible Assets [Line Items]
Impairment losses			$ 0	$ 5,400,000
Amortization expense	$ 2,000,000	$ 1,500,000	$ 3,900,000	$ 3,000,000
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Threshold of quarterly cash consideration payments		$ 6,000,000
Initial benchmark period for contingent consideration payments		30 months
Finite-lived intangible assets acquired		$ 6,000,000
Weighted-average amortization period		3 years

Other Intangible Assets, net 53

Other Intangible Assets, net - Estimated Future Amortization Expense for Acquired Intangible Assets Outstanding (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Year Ending December 31,
Remainder of 2016	$ 3,273
2,017	4,039
2,018	1,433
2,019	325
2,020	0
Thereafter	0
Net Carrying Amount	$ 9,070	$ 13,182

Earnings Per Share - Additional

Earnings Per Share - Additional Information (Detail)	Oct. 01, 2015	Apr. 15, 2015$ / sharesshares	Apr. 30, 2015$ / sharesshares	Jun. 30, 2014shares	Jun. 30, 2013USD ($)$ / sharesshares	Jun. 30, 2012shares	Jun. 30, 2016shares	Jun. 30, 2015shares	Jun. 30, 2016shares	Jun. 30, 2015shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Duration of option agreement		2 years	2 years
Number of shares available under Option Agreement (in shares)			56,934
Exercise price per share under Option Agreement (USD per share) | $ / shares		$ 22.50	$ 22.50
Stock option granted excluded from computation of earnings per share (in shares)							741,578	777,148	741,578	777,148
Convertible Debt | 2.25% Senior Convertible Notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Face amount | $					$ 172,500,000
Interest rate					2.25%
Conversion price (USD per share) | $ / shares					$ 187.62
Common Class A
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Reverse stock split (in shares)	0.1	0.1
Number of shares available under Option Agreement (in shares)		56,934
Conversion ratio								1	1
Common Class A | Controlling Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Holding units acquired by FXCM Inc. related to exchanges of Holdings units for shares of Class A common stock (in shares)								100,000	0	400,000
Common Class A | Convertible Debt | 2.25% Senior Convertible Notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Convertible debt, conversion ratio					0.00532992
Common Class A | Lucid Markets Trading Limited | Common Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Business acquisitions, shares issued (in shares)				300,000	120,000	720,000		300,000
Duration of profit target shares program						3 years

Earnings Per Share - Reconcilia

Earnings Per Share - Reconciliation of Numerator and Denominator Used in Basic and Diluted EPS Calculations (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Numerator
Income (loss) from continuing operations attributable to FXCM Inc.	$ 60,495	$ (98,886)	$ 121,765	$ (492,211)
(Loss) income from discontinued operations attributable to FXCM Inc.	(94)	3,075	(11,629)	(30,417)
Net income (loss) attributable to FXCM Inc.	60,401	(95,811)	110,136	(522,628)
Common Class A
Numerator
Net income (loss) attributable to FXCM Inc.	60,401	(95,811)	110,136	(522,628)
Earnings allocated to participating securities	0	0	0	0
Income (loss) available to common stockholders	$ 60,401	$ (95,811)	$ 110,136	$ (522,628)
Denominator
Weighted average shares of Class A common stock (in shares)	5,603,000	4,871,000	5,603,000	4,790,000
Add dilutive effect of the following:
Stock options and RSUs (in shares)	0	0	0
Convertible note hedges (in shares)	0	0	0
Warrants (in shares)	0	0	0	0
Assumed conversion of Holdings Units for Class A common stock (in shares)	0	0	0	0
Dilutive weighted average shares of Class A common stock (in shares)	5,603,000	4,871,000	5,603,000	4,790,000
Net income (loss) per share of Class A common stock — Basic and Diluted
Continuing operations (USD per share)	$ 10.80	$ (20.30)	$ 21.73	$ (102.76)
Discontinued operations (USD per share)	(0.02)	0.63	(2.08)	(6.35)
Net income (loss) attributable to FXCM Inc. (USD per share)	$ 10.78	$ (19.67)	$ 19.65	$ (109.11)

Related Party Transactions - Am

Related Party Transactions - Amounts Receivable From, And Payable To, Related Parties (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Mar. 31, 2015
Receivables
Advances to Holdings non-controlling members	$ 505	$ 112
Advances to employees	33	201
Total receivables from related parties	553	8,499
Payables
Employees	530	1,104
Tax receivable agreement	0	145	$ 0
Total payables to related parties	6,245	7,749
Lucid Markets Trading Limited
Receivables
Accounts receivable — Lucid non-controlling members	15	15
Notes receivable and interest — Lucid non-controlling members	0	8,171
Payables
Due to Lucid non-controlling members in connection with the allocation of income to Lucid non-controlling members for services provided	$ 5,715	$ 6,500

Related Partly Transactions - A

Related Partly Transactions - Additional Information (Details)	Oct. 01, 2015	Apr. 15, 2015	Jan. 31, 2014USD ($)	Jun. 30, 2016USD ($)	Jun. 30, 2015USD ($)shares	Jun. 30, 2016USD ($)shares	Jun. 30, 2015USD ($)shares	Dec. 31, 2015USD ($)	Mar. 31, 2015USD ($)
Related Party Transaction [Line Items]
Tax receivable agreement, estimated amount due				$ 146,100,000		$ 146,100,000		$ 146,800,000
Tax receivable agreement				0		0		145,000	$ 0
Payments for tax receivable agreement						188,000	$ 5,352,000
Referring broker fees				8,933,000	$ 14,601,000	$ 19,579,000	$ 30,670,000
Common Stock - Class A
Related Party Transaction [Line Items]
Conversion ratio					1	1
Reverse stock split (in shares)	0.1	0.1
Common Stock - Class A | Controlling Units
Related Party Transaction [Line Items]
Holding units acquired by FXCM Inc. related to exchanges of Holdings units for shares of Class A common stock (in shares) | shares					100,000	0	400,000
Ownership Interest and Shares Owned
Related Party Transaction [Line Items]
Memberships in exchanges owned				3,700,000		$ 3,700,000		3,700,000
Referring broker fees | Global Finance and Master Capital
Related Party Transaction [Line Items]
Referring broker fees					$ 0		$ 200,000
FastMatch Investment | Trading revenues
Related Party Transaction [Line Items]
Brokerage commissions revenue				0	3,400,000	0	6,300,000
FastMatch Investment | Communication and technology
Related Party Transaction [Line Items]
Exchange fees				0	$ 2,300,000	0	$ 4,300,000
FastMatch Investment | Other income
Related Party Transaction [Line Items]
Revenue from related parties				0		100,000
Lucid Markets Trading Limited
Related Party Transaction [Line Items]
Due to Lucid non-controlling members in connection with the allocation of income to Lucid non-controlling members for services provided				5,715,000		5,715,000		$ 6,500,000
Lucid Markets Trading Limited | Notes Receivable
Related Party Transaction [Line Items]
Notes receivable			$ 7,900,000
Related party notes receivable interest rate			2.00%
Allowance for notes				$ 8,200,000		$ 8,200,000
Shareholder great than a 5% ownership | Global Finance and Master Capital
Related Party Transaction [Line Items]
Percentage of ownership interests (more than)				90.00%		90.00%
FastMatch Investment
Related Party Transaction [Line Items]
Percentage of equity interest					35.10%		35.10%

Net Capital Requirements - Mini

Net Capital Requirements - Minimum Capital Requirement And Excess Capital (Detail) - USD ($) $ in Millions	Jun. 30, 2016	Dec. 31, 2015
US
Capital Requirements on Foreign Financial Institutions [Line Items]
Capital	$ 53.2	$ 43.6
Minimum capital requirement	34.2	28.3
Excess capital	19	15.3
UK LTD
Capital Requirements on Foreign Financial Institutions [Line Items]
Capital	84.9	76.3
Minimum capital requirement	21.3	27.6
Excess capital	63.6	48.7
Australia
Capital Requirements on Foreign Financial Institutions [Line Items]
Capital	12.3	12
Minimum capital requirement	0.7	0.7
Excess capital	11.6	11.3
Lucid LLP
Capital Requirements on Foreign Financial Institutions [Line Items]
Capital	11.7	10.9
Minimum capital requirement	4.8	4
Excess capital	$ 6.9	$ 6.9

Leucadia Transaction - Addition

Leucadia Transaction - Additional Information (Details)	Mar. 10, 2016USD ($)directormember	Apr. 16, 2015USD ($)	Jan. 24, 2015USD ($)	Jan. 15, 2015USD ($)	Jun. 30, 2016USD ($)$ / shares	Jun. 30, 2015USD ($)	Jun. 30, 2016USD ($)$ / shares	Jun. 30, 2015USD ($)	Jun. 30, 2016USD ($)$ / shares	Dec. 31, 2015USD ($)
Unusual or Infrequent Item [Line Items]
Derivative, exchange rate floor				1.2
Bad debt (recovery) expense					$ (141,000)	$ 388,000	$ (141,000)	$ 257,303,000
Extension period of credit agreement	1 year
Number of board members | member	8
Number of directors on the board appointed by a third-party | director	3
Number of directors on the board appointed by the company | director	3
Number of independent directors on the board | director	2
Number of independent directors nominated by a third-party | director	1
Long-term debt					180,153,000		180,153,000		$ 180,153,000	$ 147,262,000
Deferred finance costs, gross			$ 1,800,000
Effective interest rate			39.80%
Loss on derivative, net					16,314,000	(19,591,000)	21,208,000	(33,072,000)
Derivative liability					209,458,000		209,458,000		$ 209,458,000	448,458,000
Gain on derivative liability					$ 116,529,000	(99,867,000)	227,360,000	(392,296,000)
Discount issuance fee, gross			$ 21,000,000
Amortization of deferred financing cost							$ 604,000	2,049,000
Letter Agreement
Unusual or Infrequent Item [Line Items]
Deferred finance costs, gross			1,200,000
Fair value of derivative liability			124,800,000
Loss on derivative, net								30,400,000
Valuation based on common stock closing price per share (USD per share) | $ / shares					$ 8.65		$ 8.65		$ 8.65
Effect of $0.25 increase in common stock price, increase in fair value					$ 44,100,000		$ 44,100,000		$ 44,100,000
Effect of $0.25 decrease in common stock price, decrease in fair value					46,600,000		46,600,000		46,600,000
Effect of 10% increase in expected volatility rate, decrease in fair value					600,000		600,000		600,000
Effect of 10% decrease in expected volatility rate, increase in fair value					600,000		600,000		600,000
Discount issuance fee, gross			7,100,000
Letter Agreement | Loss on Derivative Liability - Letter Agreement
Unusual or Infrequent Item [Line Items]
Gain on derivative liability					128,200,000		239,000,000
Letter Agreement | Derivative Liability - Letter Agreement
Unusual or Infrequent Item [Line Items]
Derivative liability					209,500,000		209,500,000		209,500,000	448,500,000
Credit Agreement
Unusual or Infrequent Item [Line Items]
Long-term debt					180,153,000		180,153,000		180,153,000	147,262,000
Deferred finance costs, gross			600,000
Derivative liability					11,600,000		11,600,000		11,600,000	0
Effect of 5% increase in recovery rate, decrease in fair value					800,000		800,000		800,000
Effect of 5% decrease in recovery rate, increase in fair value					500,000		500,000		500,000
Effect of $25M acceleration in principal repayments, increase in fair value					2,600,000		2,600,000		2,600,000
Effect of $25M deceleration in principal repayments, decrease in fair value					900,000		900,000		900,000
Discount issuance fee, gross			13,900,000
Amortization of issuance fee discount					1,248,000	3,539,000	2,390,000	5,318,000
Amortization of deferred financing cost					111,000	316,000	213,000	475,000
Unamortized debt issuance cost					253,000		253,000		253,000	$ 467,000
Amortization of deferred financing fee					898,000	2,548,000	1,720,000	3,828,000
Credit Agreement | Interest on Borrowings
Unusual or Infrequent Item [Line Items]
Amortization of issuance fee discount					1,200,000	3,500,000	2,400,000	5,300,000
Amortization of deferred financing cost					100,000	300,000	200,000	500,000
Amortization of deferred financing fee					900,000	2,500,000	1,700,000	3,800,000
Leucadia | Letter Agreement
Unusual or Infrequent Item [Line Items]
Face amount			94,400,000
Leucadia | Credit Agreement
Unusual or Infrequent Item [Line Items]
Face amount			184,600,000
Next $350 million
Unusual or Infrequent Item [Line Items]
Letter agreement, stipulated proceeds amount	$ 350,000,000		350,000,000
Next $500 million
Unusual or Infrequent Item [Line Items]
Letter agreement, stipulated proceeds amount	500,000,000	$ 500,000,000
Next $500 million | Minimum
Unusual or Infrequent Item [Line Items]
Letter agreement, stipulated proceeds amount	350,000,000		500,000,000
Next $500 million | Maximum
Unusual or Infrequent Item [Line Items]
Letter agreement, stipulated proceeds amount	850,000,000		$ 680,000,000
All aggregate amounts thereafter
Unusual or Infrequent Item [Line Items]
Letter agreement, stipulated proceeds amount	$ 850,000,000
Senior Management
Unusual or Infrequent Item [Line Items]
Long-term incentive plan, vesting period	5 years
Newco
Unusual or Infrequent Item [Line Items]
Noncontrolling equity interest	49.90%
Ownership percentage by parent	50.10%
FXCM Holdings
Unusual or Infrequent Item [Line Items]
Percentage of ownership interests			90.00%
FXCM Holdings | Leucadia | Loans Payable
Unusual or Infrequent Item [Line Items]
Percentage of equity interest of foreign subsidiaries pledged as collateral			65.00%
FXCM Holdings | Next $350 million
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions	45.00%		50.00%
FXCM Holdings | Next $500 million
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions	8.80%		10.00%
FXCM Holdings | All aggregate amounts thereafter
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions	34.40%		40.00%
FXCM Holdings | Senior Management | Next $350 million
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions	10.00%
FXCM Holdings | Senior Management | Next $500 million
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions	12.00%
FXCM Holdings | Senior Management | All aggregate amounts thereafter
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions	14.00%
Holdings and Newco | Leucadia | Loans Payable
Unusual or Infrequent Item [Line Items]
Face amount			$ 300,000,000
Net proceeds from debt			$ 279,000,000
Interest rate			10.00%
Quarterly increase in interest rate			1.50%
Maximum interest rate			20.50%
Default on debt, increase to applicable interest rate			2.00%
Deferred financing fee			$ 10,000,000
Increase in deferred financing fee			30,000,000
Deferred financing fee, threshold to increase financing fee, maximum amount outstanding			250,000,000
Repayments of long-term debt		56,500,000							$ 117,500,000
Long-term debt		$ 243,500,000
Deferred finance costs, gross			$ 21,000,000
Parent Company
Unusual or Infrequent Item [Line Items]
Change in control, majority of directors no longer on board for period			12 months
Parent Company | Minimum
Unusual or Infrequent Item [Line Items]
Percentage of voting interests			40.00%
Swiss National Bank
Unusual or Infrequent Item [Line Items]
Derivative, exchange rate floor				1.2
Foreign Exchange
Unusual or Infrequent Item [Line Items]
Margin receivable expected to be uncollectible due to foreign currency losses incurred by customers				$ 275,100,000
Foreign Exchange | Margin Receivable
Unusual or Infrequent Item [Line Items]
Bad debt (recovery) expense					0		0
Foreign Exchange | Margin Receivable | Continuing Operations
Unusual or Infrequent Item [Line Items]
Allowance for doubtful accounts receivable, recoveries					$ 100,000	100,000	$ 100,000
Bad debt (recovery) expense						300,000		9,300,000
Bad debt expense, net of recoveries						400,000		257,300,000
Foreign Exchange | Margin Receivable | Discontinued Operations
Unusual or Infrequent Item [Line Items]
Allowance for doubtful accounts receivable, recoveries						0		100,000
Bad debt expense, net of recoveries						$ 0		$ 8,400,000

Leucadia Transaction - Allocati

Leucadia Transaction - Allocation of Net Proceeds (Details) - USD ($)	Mar. 10, 2016	Apr. 16, 2015	Jan. 24, 2015
Next $350 million
Unusual or Infrequent Item [Line Items]
Letter agreement, stipulated proceeds amount	$ 350,000,000		$ 350,000,000
Next $500 million
Unusual or Infrequent Item [Line Items]
Letter agreement, stipulated proceeds amount	500,000,000	$ 500,000,000
All aggregate amounts thereafter
Unusual or Infrequent Item [Line Items]
Letter agreement, stipulated proceeds amount	$ 850,000,000
Leucadia | Amounts due under Leucadia term loan, including fees
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions	100.00%		100.00%
Leucadia | Next $350 million
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions	45.00%		50.00%
Leucadia | Next $500 million
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions	79.20%		90.00%
Leucadia | All aggregate amounts thereafter
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions	51.60%		60.00%
FXCM Holdings | Amounts due under Leucadia term loan, including fees
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions	0.00%		0.00%
FXCM Holdings | Next $350 million
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions	45.00%		50.00%
FXCM Holdings | Next $500 million
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions	8.80%		10.00%
FXCM Holdings | All aggregate amounts thereafter
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions	34.40%		40.00%
Senior Management | FXCM Holdings | Amounts due under Leucadia term loan, including fees
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions	0.00%
Senior Management | FXCM Holdings | Next $350 million
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions	10.00%
Senior Management | FXCM Holdings | Next $500 million
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions	12.00%
Senior Management | FXCM Holdings | All aggregate amounts thereafter
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions	14.00%

Leucadia Transaction - Credit A

Leucadia Transaction - Credit Agreement Carrying Value (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Debt — net carrying value	$ 180,153	$ 147,262
Credit Agreement
Debt Instrument [Line Items]
Debt principal	192,543	192,685
Original issue discount	(18,898)	(35,967)
Discount — issuance fee	(2,837)	(5,227)
Deferred financing fee	(2,042)	(3,762)
Debt issuance costs	(253)	(467)
Debt Instrument, Mandatory Prepayment Provision	11,640	0
Debt — net carrying value	$ 180,153	$ 147,262

Leucadia Transaction - Credit62

Leucadia Transaction - Credit Agreement Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Debt Instrument [Line Items]
Amortization of original issue discount — Credit Agreement			$ 17,070	$ 40,687
Amortization of debt issuance costs			604	2,049
Credit Agreement
Debt Instrument [Line Items]
Contractual interest	$ 8,406	$ 6,653	16,092	12,901
Deferred interest	(967)	2,168	(1,210)	4,852
Amortization of original issue discount — Credit Agreement	8,762	26,411	17,070	40,687
Amortization of issuance fee discount	1,248	3,539	2,390	5,318
Amortization of deferred financing fee	898	2,548	1,720	3,828
Amortization of debt issuance costs	111	316	213	475
Total interest expense	$ 18,458	$ 41,635	$ 36,275	$ 68,061

Debt - Additional Information (

Debt - Additional Information (Details)	Oct. 01, 2015	Apr. 15, 2015	Jan. 20, 2015USD ($)	Jun. 30, 2013USD ($)$ / shares	Jun. 30, 2016USD ($)	Jun. 30, 2015USD ($)	Jun. 30, 2016USD ($)	Jun. 30, 2015USD ($)	Jan. 26, 2016$ / shares	Dec. 31, 2015USD ($)	Jan. 24, 2015
Debt Instrument [Line Items]
Interest on borrowings					$ 21,202,000	$ 44,291,000	$ 41,755,000	$ 74,850,000
Exercise price of warrants (USD per share) | $ / shares									$ 44.12
Effective interest rate											39.80%
Common Stock - Class A
Debt Instrument [Line Items]
Reverse stock split (in shares)	0.1	0.1
2.25% Senior Convertible Notes
Debt Instrument [Line Items]
Exercise price of warrants (USD per share) | $ / shares				$ 212.40
Cost of hedge				$ 29,100,000
Proceeds from sale of warrants				18,600,000
2.25% Senior Convertible Notes | Convertible Debt
Debt Instrument [Line Items]
Face amount				$ 172,500,000
Interest rate				2.25%
Proceeds from issuance of senior convertibles notes, net				$ 166,500,000
Conversion price (USD per share) | $ / shares				$ 187.62
Equity component				$ 29,100,000	29,101,000		29,101,000			$ 29,101,000
Convertible notes				144,100,000	157,795,000		157,795,000			154,255,000
Deferred bond discount				$ 29,100,000	12,380,000		12,380,000			15,315,000
Effective interest rate				6.20%
Debt issuance cost				$ 6,000,000
Unamortized debt issuance cost					$ 2,325,000		$ 2,325,000			2,930,000
2.25% Senior Convertible Notes | Convertible Debt | Common Stock - Class A
Debt Instrument [Line Items]
Convertible debt, conversion ratio				0.00532992
Revolving Credit Facility
Debt Instrument [Line Items]
Repayments of lines of credit			$ 25,000,000
Interest on borrowings						0		1,500,000
Weighted average dollar amount of borrowings related to credit agreement						$ 0		$ 2,600,000
Weighted average interest rate						0.00%		2.90%
Other Noncurrent Assets | Accounting Standards Update 2015-03 | 2.25% Senior Convertible Notes | Convertible Debt
Debt Instrument [Line Items]
Unamortized debt issuance cost										(2,900,000)
Long-term Debt | Accounting Standards Update 2015-03 | 2.25% Senior Convertible Notes | Convertible Debt
Debt Instrument [Line Items]
Unamortized debt issuance cost										$ 2,900,000

Debt - Convertible Debt (Detail

Debt - Convertible Debt (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015	Jun. 30, 2013
Interest Expense, Debt [Abstract]
Interest expense - amortization of deferred bond discount			$ 17,070	$ 40,687
Amortization of deferred financing cost			604	2,049
2.25% Senior Convertible Notes | Convertible Debt
Debt Instrument [Line Items]
Liability component — principal	$ 172,500		172,500		$ 172,500
Deferred bond discount	(12,380)		(12,380)		(15,315)	$ (29,100)
Debt issuance costs	(2,325)		(2,325)		(2,930)
Liability component — net carrying value	157,795		157,795		154,255	144,100
Equity component	29,101		29,101		$ 29,101	$ 29,100
Interest Expense, Debt [Abstract]
Contractual interest	971	$ 970	1,941	1,941
Interest expense - amortization of deferred bond discount	1,471	1,384	2,935	2,761
Amortization of deferred financing cost	302	302	604	605
Total interest expense	$ 2,744	$ 2,656	$ 5,480	$ 5,307

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) - Cybersecurity Incident - USD ($)	3 Months Ended	6 Months Ended	9 Months Ended
	Jun. 30, 2016	Jun. 30, 2016	Jun. 30, 2016
Loss Contingencies [Line Items]
Professional Fees	$ 0	$ 0	$ 700,000
Insurance Recoveries	$ 200,000	$ 200,000

Derivative Financial Instrume66

Derivative Financial Instruments - Gross and Net Fair Value of Derivatives (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Derivative Assets
Total derivatives, gross	$ 11,884	$ 10,921
Netting agreements and cash collateral netting	(9,037)	(8,909)
Total derivatives, net	2,847	2,012
Notional	145,954	920,074
Derivative Liabilities
Total derivative liabilities	21,431	8,943
Netting agreements and cash collateral netting	(9,037)	(8,909)
Total derivative liabilities	12,394	34
Notional	1,823,354	1,164,557
Discontinued Operations
Derivative Assets
Total derivatives, gross	11,600	9,700
Netting agreements and cash collateral netting	(8,800)	(8,800)
Derivative Liabilities
Total derivative liabilities	9,000	8,800
Netting agreements and cash collateral netting	(8,800)	(8,800)
Continuing Operations
Derivative Assets
Total derivatives, gross	300	1,200
Netting agreements and cash collateral netting	(300)	(100)
Derivative Liabilities
Total derivative liabilities	12,400	100
Netting agreements and cash collateral netting	(300)	(100)
Exchange traded options
Derivative Assets
Total derivatives, gross	9,907	6,503
Notional	30,007	15,399
Derivative Liabilities
Total derivative liabilities	0	5,805
Notional	0	18,282
CFD contracts
Derivative Assets
Total derivatives, gross	2	206
Notional	1,863	109,715
Derivative Liabilities
Total derivative liabilities	0	36
Notional	0	99,036
Futures contracts
Derivative Assets
Total derivatives, gross	720	4,212
Notional	39,839	794,960
Derivative Liabilities
Total derivative liabilities	19,920	3,102
Notional	1,754,330	$ 1,047,239
OTC options
Derivative Assets
Total derivatives, gross	1,255
Notional	74,245
Derivative Liabilities
Total derivative liabilities	1,511
Notional	$ 69,024

Derivative Financial Instrume67

Derivative Financial Instruments - Gains (Losses) from Derivatives (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on derivatives	$ (16,314)	$ 19,591	$ (21,208)	$ 33,072
Income (loss) from continuing operations
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on derivatives	(17,700)	11,100	(25,300)	18,300
Exchange traded options
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on derivatives	737	1,176	11,091	(729)
CFD contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on derivatives	(1,305)	415	(1,445)	(5,347)
Futures contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on derivatives	(15,736)	18,000	(30,856)	38,062
OTC options
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on derivatives	$ (10)	$ 0	$ 2	$ 1,086

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value Measured on a Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Financial Assets:
Total derivatives, gross	$ 11,884	$ 10,921
Netting agreements and cash collateral netting	(9,037)	(8,909)
Total due to brokers	2,847	2,012
Financial Liabilities:
Total derivative liabilities	21,431	8,943
Netting agreements and cash collateral netting	(9,037)	(8,909)
Due to brokers total	12,394	34
Notional amount of open FX and CFD customer assets	145,954	920,074
Notional amount of open FX and CFD customer liabilities	1,823,354	1,164,557
Open FX Positions
Financial Liabilities:
Notional amount of open FX and CFD customer assets	1,400,000	2,500,000
Notional amount of open FX and CFD customer liabilities	1,800,000	2,500,000
Net notional amount of open FX and CFD positions	1,500,000	2,200,000
Exchange traded options
Financial Assets:
Total derivatives, gross	9,907	6,503
Financial Liabilities:
Total derivative liabilities	0	5,805
Notional amount of open FX and CFD customer assets	30,007	15,399
Notional amount of open FX and CFD customer liabilities	0	18,282
CFD contracts
Financial Assets:
Total derivatives, gross	2	206
Financial Liabilities:
Total derivative liabilities	0	36
Notional amount of open FX and CFD customer assets	1,863	109,715
Notional amount of open FX and CFD customer liabilities	0	99,036
Futures contracts
Financial Assets:
Total derivatives, gross	720	4,212
Financial Liabilities:
Total derivative liabilities	19,920	3,102
Notional amount of open FX and CFD customer assets	39,839	794,960
Notional amount of open FX and CFD customer liabilities	1,754,330	1,047,239
OTC options
Financial Assets:
Total derivatives, gross	1,255
Financial Liabilities:
Total derivative liabilities	1,511
Notional amount of open FX and CFD customer assets	74,245
Notional amount of open FX and CFD customer liabilities	69,024
Level 1
Financial Assets:
Total assets	0	0
Financial Liabilities:
Total liabilities	0	0
Level 2
Financial Assets:
Total assets	27,023	32,658
Financial Liabilities:
Total liabilities	59,982	122,226
Level 3
Financial Assets:
Total assets	13,903	26,924
Financial Liabilities:
Total liabilities	164,253	192,685
Fair Value, Measurements, Recurring
Financial Assets:
Netting agreements and cash collateral netting	(9,037)	(8,909)
Total due to brokers	2,847	2,012
Total assets	2,847	2,012
Financial Liabilities:
Customer account liabilities	662,392	685,043
Fair Value Inputs, Mandatory Prepayment Provision	11,640
Netting agreements and cash collateral netting	(9,037)	(8,909)
Due to brokers total	12,394	34
Securities sold, not yet purchased	3,896	3,624
Total liabilities	899,780	1,137,159
Fair Value, Measurements, Recurring | Exchange traded options
Financial Assets:
Total derivatives, gross	9,907	6,503
Financial Liabilities:
Total derivative liabilities		5,805
Fair Value, Measurements, Recurring | CFD contracts
Financial Assets:
Total derivatives, gross	2	206
Financial Liabilities:
Total derivative liabilities		36
Fair Value, Measurements, Recurring | Futures contracts
Financial Assets:
Total derivatives, gross	720	4,212
Financial Liabilities:
Total derivative liabilities	19,920	3,102
Fair Value, Measurements, Recurring | OTC options
Financial Assets:
Total derivatives, gross	1,255
Financial Liabilities:
Total derivative liabilities	1,511
Fair Value, Measurements, Recurring | Letter Agreement
Financial Liabilities:
Total derivative liabilities	209,458	448,458
Fair Value, Measurements, Recurring | Counterparty and Cash Collateral Netting
Financial Assets:
Netting agreements and cash collateral netting	(9,037)	(8,909)
Financial Liabilities:
Fair Value Inputs, Mandatory Prepayment Provision	0
Netting agreements and cash collateral netting	(9,037)	(8,909)
Fair Value, Measurements, Recurring | Level 1
Financial Assets:
Total derivatives, gross	10,627	10,715
Total assets	10,627	10,715
Financial Liabilities:
Customer account liabilities	0	0
Total derivative liabilities	19,920	8,907
Fair Value Inputs, Mandatory Prepayment Provision	0
Securities sold, not yet purchased	3,896	3,624
Total liabilities	23,816	12,531
Fair Value, Measurements, Recurring | Level 1 | Exchange traded options
Financial Assets:
Total derivatives, gross	9,907	6,503
Financial Liabilities:
Total derivative liabilities		5,805
Fair Value, Measurements, Recurring | Level 1 | CFD contracts
Financial Assets:
Total derivatives, gross	0	0
Financial Liabilities:
Total derivative liabilities		0
Fair Value, Measurements, Recurring | Level 1 | Futures contracts
Financial Assets:
Total derivatives, gross	720	4,212
Financial Liabilities:
Total derivative liabilities	19,920	3,102
Fair Value, Measurements, Recurring | Level 1 | OTC options
Financial Assets:
Total derivatives, gross	0
Financial Liabilities:
Total derivative liabilities	0
Fair Value, Measurements, Recurring | Level 1 | Letter Agreement
Financial Liabilities:
Total derivative liabilities	0	0
Fair Value, Measurements, Recurring | Level 2
Financial Assets:
Total derivatives, gross	1,257	206
Total assets	1,257	206
Financial Liabilities:
Customer account liabilities	662,392	685,043
Total derivative liabilities	1,511	36
Fair Value Inputs, Mandatory Prepayment Provision	0
Securities sold, not yet purchased	0	0
Total liabilities	663,903	685,079
Fair Value, Measurements, Recurring | Level 2 | Exchange traded options
Financial Assets:
Total derivatives, gross	0	0
Financial Liabilities:
Total derivative liabilities		0
Fair Value, Measurements, Recurring | Level 2 | CFD contracts
Financial Assets:
Total derivatives, gross	2	206
Financial Liabilities:
Total derivative liabilities		36
Fair Value, Measurements, Recurring | Level 2 | Futures contracts
Financial Assets:
Total derivatives, gross	0	0
Financial Liabilities:
Total derivative liabilities	0	0
Fair Value, Measurements, Recurring | Level 2 | OTC options
Financial Assets:
Total derivatives, gross	1,255
Financial Liabilities:
Total derivative liabilities	1,511
Fair Value, Measurements, Recurring | Level 2 | Letter Agreement
Financial Liabilities:
Total derivative liabilities	0	0
Fair Value, Measurements, Recurring | Level 3
Financial Assets:
Total derivatives, gross	0	0
Total assets	0	0
Financial Liabilities:
Customer account liabilities	0	0
Total derivative liabilities	0	0
Fair Value Inputs, Mandatory Prepayment Provision	11,640
Securities sold, not yet purchased	0	0
Total liabilities	221,098	448,458
Fair Value, Measurements, Recurring | Level 3 | Exchange traded options
Financial Assets:
Total derivatives, gross	0	0
Financial Liabilities:
Total derivative liabilities		0
Fair Value, Measurements, Recurring | Level 3 | CFD contracts
Financial Assets:
Total derivatives, gross	0	0
Financial Liabilities:
Total derivative liabilities		0
Fair Value, Measurements, Recurring | Level 3 | Futures contracts
Financial Assets:
Total derivatives, gross	0	0
Financial Liabilities:
Total derivative liabilities	0	0
Fair Value, Measurements, Recurring | Level 3 | OTC options
Financial Assets:
Total derivatives, gross	0
Financial Liabilities:
Total derivative liabilities	0
Fair Value, Measurements, Recurring | Level 3 | Letter Agreement
Financial Liabilities:
Total derivative liabilities	$ 209,458	$ 448,458

Fair Value Measurements - Fai69

Fair Value Measurements - Fair Value Assumptions (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2015
Letter Agreement
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Effect of 10% increase in expected volatility rate, decrease in fair value	$ 0.6
Effect of 10% decrease in expected volatility rate, increase in fair value	$ 0.6
Option-Pricing Method
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Term (years)	2 years	2 years 6 months 12 days
Volatility	133.60%	79.10%
Risk-free rate	0.60%	1.20%
Dividend yield	0.00%	0.00%
Reliance placed on public indication of value	100.00%	100.00%

Fair Value Measurements - Manda

Fair Value Measurements - Mandatory Prepayment Provision (Details) - Mandatory Prepayment Provision $ in Millions	Jun. 30, 2016USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Average Recovery Rate for Debt Instruments	53.40%
Effect of 5% increase in recovery rate, decrease in fair value	$ 0.8
Effect of 5% decrease in recovery rate, increase in fair value	0.5
Effect of $25M acceleration in principal repayments, increase in fair value	2.6
Effect of $25M deceleration in principal repayments, decrease in fair value	$ 0.9

Fair Value Measurements - Fai71

Fair Value Measurements - Fair Value by Balance Sheet Groupings (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Level 1
Financial Assets:
Due from brokers — unsettled spot FX	$ 0	$ 0
Due from brokers — unsettled common stock	0	0
Due from brokers — excess cash collateral	0	0
Equity method investments	0	0
Cost method investment	0
Notes receivable		0
Exchange memberships	0	0
Total assets	0	0
Financial Liabilities:
Due to brokers — unsettled spot FX	0	0
Senior convertible notes	0	0
Credit Agreement	0	0
Total liabilities	0	0
Level 2
Financial Assets:
Due from brokers — unsettled spot FX	2,161	2,939
Due from brokers — unsettled common stock	3,054	3,054
Due from brokers — excess cash collateral	12,559	18,010
Equity method investments	0	0
Cost method investment	0
Notes receivable		0
Exchange memberships	9,249	8,655
Total assets	27,023	32,658
Financial Liabilities:
Due to brokers — unsettled spot FX	38	1,039
Senior convertible notes	59,944	121,187
Credit Agreement	0	0
Total liabilities	59,982	122,226
Level 3
Financial Assets:
Due from brokers — unsettled spot FX	0	0
Due from brokers — unsettled common stock	0	0
Due from brokers — excess cash collateral	0	0
Equity method investments	12,800	19,043
Cost method investment	1,103
Notes receivable		7,881
Exchange memberships	0	0
Total assets	13,903	26,924
Financial Liabilities:
Due to brokers — unsettled spot FX	0	0
Senior convertible notes	0	0
Credit Agreement	164,253	192,685
Total liabilities	164,253	192,685
Carrying Value
Financial Assets:
Due from brokers — unsettled spot FX	2,161	2,939
Due from brokers — unsettled common stock	3,054	3,054
Due from brokers — excess cash collateral	12,559	18,010
Equity method investments	6,505	8,273
Cost method investment	1,103
Notes receivable		7,881
Exchange memberships	9,434	9,434
Total assets	34,816	49,591
Financial Liabilities:
Due to brokers — unsettled spot FX	38	1,039
Senior convertible notes	157,795	157,185
Credit Agreement	180,153	147,729
Total liabilities	337,986	305,953
Fair Value
Financial Assets:
Due from brokers — unsettled spot FX	2,161	2,939
Due from brokers — unsettled common stock	3,054	3,054
Due from brokers — excess cash collateral	12,559	18,010
Equity method investments	12,800	19,043
Cost method investment	1,103
Notes receivable		7,881
Exchange memberships	9,249	8,655
Total assets	40,926	59,582
Financial Liabilities:
Due to brokers — unsettled spot FX	38	1,039
Senior convertible notes	59,944	121,187
Credit Agreement	164,253	192,685
Total liabilities	$ 224,235	$ 314,911

Fair Value Measurements - Level

Fair Value Measurements - Level 3 Rollforward (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 337,627	$ 386,230	$ 448,458	$ 0
Additions	11,640	0	11,640	94,436
Net Unrealized (Gain) Loss	(128,169)	99,867	(239,000)	391,661
Ending balance	221,098	486,097	221,098	486,097
Letter Agreement
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	337,627	386,230	448,458	0
Additions	0	0	0	94,436
Net Unrealized (Gain) Loss	(128,169)	99,867	(239,000)	391,661
Ending balance	209,458	$ 486,097	209,458	$ 486,097
Mandatory Prepayment Provision
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	0		0
Additions	11,640		11,640
Net Unrealized (Gain) Loss	0		0
Ending balance	$ 11,640		$ 11,640

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details) $ / shares in Units, $ in Millions	Jan. 26, 2016$ / shares	Oct. 01, 2015	Apr. 15, 2015USD ($)$ / sharesshares	Apr. 30, 2015$ / sharesshares	Jan. 29, 2015
Class of Stock [Line Items]
Preferred stock, conversion ratio	0.001
Exercise price of right per thousandth preferred share (USD per share) | $ / shares	$ 44.12
Beneficial ownership in outstanding common stock threshold (percentage)	4.90%				4.90%
Number of shares available under Option Agreement (in shares) | shares				56,934
Exercise price per share under Option Agreement (USD per share) | $ / shares			$ 22.50	$ 22.50
Duration of option agreement			2 years	2 years
Fair value of options at issuance | $			$ 0.3
Common Stock - Class A
Class of Stock [Line Items]
Common stock, dividend declared, rights per share	1
Reverse stock split (in shares)		0.1	0.1
Number of shares available under Option Agreement (in shares) | shares			56,934

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Tax Disclosure [Abstract]
Effective tax rate	(0.50%)	(1.00%)	0.10%	(30.00%)
Valuation allowance, decrease	$ 23.6
Deferred tax assets, valuation allowance		$ 57.3		$ 57.3

Litigation - Additional Informa

Litigation - Additional Information (Detail)	1 Months Ended				3 Months Ended	6 Months Ended
	Sep. 30, 2015USD ($)	Jun. 30, 2015USD ($)	Feb. 28, 2015USD ($)	Jan. 31, 2014USD ($)	Jun. 30, 2016USD ($)	Jun. 30, 2016USD ($)	Jan. 15, 2015
Loss Contingencies [Line Items]
Derivative, exchange rate floor							1.2
Range of loss, minimum					$ 0	$ 0
Range of loss, maximum					1,500,000	1,500,000
Swiss National Bank
Loss Contingencies [Line Items]
Derivative, exchange rate floor							1.2
HK | Securities and Futures Commission
Loss Contingencies [Line Items]
Loss contingency accrual					2,000,000	2,000,000
Loss contingency accrual, provision					500,000	500,000
US vs Revelation Forex Fund, Kevin G. White, and Related Entities | US
Loss Contingencies [Line Items]
Damages sought (in excess of)		$ 2,000,000
Settlement amount					$ 2,300,000	$ 2,300,000
Restitution to Affected Clients | FSL | FCA Draft Warning Notice
Loss Contingencies [Line Items]
Settlement amount			$ 700,000
US vs Commodity Futures Trading Commission | US
Loss Contingencies [Line Items]
Settlement amount	$ 700,000
Settlement, disgorged commissions and fees	$ 100,000
Minimum | US vs Revelation Forex Fund, Kevin G. White, and Related Entities | US
Loss Contingencies [Line Items]
Damages sought (in excess of)				$ 3,800,000