Global Brokerage (GLBR) 10-Q 6 Nov 15 2015 Q3 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	9 Months Ended
	Sep. 30, 2015	Nov. 04, 2015
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	Sep. 30, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q3
Trading Symbol	FXCM
Amendment Flag	false
Common Stock - Class A
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		5,372,666
Common Stock - Class B
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		27

Condensed Consolidated Statemen

Condensed Consolidated Statements of Financial Condition - USD ($) $ in Thousands		Sep. 30, 2015	Dec. 31, 2014
Current assets
Cash and cash equivalents		$ 186,369	$ 256,887
Cash and cash equivalents, held for customers		713,204	901,227
Due from brokers		24,007	9,772
Accounts receivable, net		13,894	7,209
Deferred tax asset		0	9,065
Tax receivable		2,626	1,381
Current assets held for sale		357,894	548,506
Total current assets		1,297,994	1,734,047
Deferred tax asset		0	172,619
Office, communication and computer equipment, net		37,335	39,028
Goodwill		28,656	39,242
Other intangible assets, net		15,787	15,338
Notes receivable		7,881	9,381
Other assets		17,512	14,829
Noncurrent assets held for sale		0	362,943
Noncurrent assets held for sale		1,405,165	2,387,427
Current liabilities
Customer account liabilities		713,204	901,227
Accounts payable and accrued expenses		48,635	35,189
Revolving credit agreement		0	25,000
Due to brokers		60	15,983
Due to related parties pursuant to tax receivable agreement		0	5,352
Current liabilities held for sale		84,057	455,915
Total current liabilities		845,956	1,438,666
Deferred tax liability		944	1,698
Senior convertible notes		155,758	151,578
Credit Agreement		145,330	0
Due to related parties pursuant to tax receivable agreement		0	145,224
Derivative liability — Letter Agreement		348,531	0
Other liabilities		16,294	5,957
Noncurrent liabilities held for sale		0	1,288
Total liabilities		$ 1,512,813	$ 1,744,411
Commitments and Contingencies (See Note 14)
Stockholders’ (Deficit) Equity
Additional paid-in capital(1)	[1]	$ 273,313	$ 274,139
(Accumulated deficit) retained earnings		(426,600)	22,379
Accumulated other comprehensive income (loss)		570	(11,879)
Total stockholders’ (deficit) equity, FXCM Inc.		(152,662)	284,688
Non-controlling interests		45,014	358,328
Total stockholders’ (deficit) equity		(107,648)	643,016
Total liabilities and stockholders’ (deficit) equity		1,405,165	2,387,427
Common Stock - Class A
Stockholders’ (Deficit) Equity
Common stock		54	48
Common Stock - Class B
Stockholders’ (Deficit) Equity
Common stock		$ 1	$ 1
[1]	Adjusted to reflect the impact of the one-for-ten reverse stock split that became effective on October 1, 2015, as discussed in Note 1.

Condensed Consolidated Stateme3

Condensed Consolidated Statements of Financial Condition (Parenthetical) - $ / shares		Sep. 30, 2015	Dec. 31, 2014
Common Stock - Class A
Common stock, par value (in dollars per share)		$ 0.01	$ 0.01
Common stock, shares authorized		3,000,000,000	3,000,000,000
Common stock, shares issued	[1]	5,372,666	4,788,996
Common stock, shares outstanding	[1]	5,372,666	4,788,996
Common Stock - Class B
Common stock, par value (in dollars per share)		$ 0.01	$ 0.01
Common stock, shares authorized		1,000,000	1,000,000
Common stock, shares issued		27	34
Common stock, shares outstanding		27	34
[1]	Adjusted to reflect the impact of the one-for-ten reverse stock split that became effective on October 1, 2015, as discussed in Note 1.

Condensed Consolidated Stateme4

Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Revenues
Trading revenue		$ 56,247	$ 88,696	$ 184,672	$ 245,294
Interest income		494	519	1,232	1,493
Brokerage interest expense		(212)	(174)	(589)	(370)
Net interest revenue		282	345	643	1,123
Other income		3,053	2,344	149,969	2,889
Total net revenues		59,582	91,385	335,284	249,306
Operating Expenses
Compensation and benefits		23,948	23,317	72,444	72,680
Referring broker fees		13,032	20,735	43,702	55,652
Advertising and marketing		4,116	4,067	10,416	16,226
Communication and technology		7,312	10,451	26,072	28,446
Trading costs, prime brokerage and clearing fees		847	2,394	2,947	5,946
General and administrative		12,861	14,872	39,234	41,678
Bad debt expense		0	0	257,303	0
Depreciation and amortization		7,316	7,917	21,136	20,506
Goodwill impairment loss		0	0	9,513	0
Total operating expenses		69,432	83,753	482,767	241,134
Operating (loss) income		(9,850)	7,632	(147,483)	8,172
Other Income (Expense)
Gain (loss) on derivative liability — Letter Agreement		137,566	0	(254,730)	0
Loss on equity method investments, net		111	137	299	304
Interest on borrowings		28,974	3,028	103,824	9,121
Income (loss) from continuing operations before income taxes		98,631	4,467	(506,336)	(1,253)
Income tax provision		295	1,350	181,616	1,366
Income (loss) from continuing operations		98,336	3,117	(687,952)	(2,619)
Income (loss) from discontinued operations, net of tax		18,018	(357)	(74,915)	69
Net income (loss)		116,354	2,760	(762,867)	(2,550)
Net income (loss) attributable to FXCM Inc.		73,649	2,392	(448,979)	1,391
Income (loss) from continuing operations attributable to FXCM Inc.		64,302	1,956	(427,909)	(1,431)
Income (loss) from discontinued operations attributable to FXCM Inc.		$ 9,347	$ 436	$ (21,070)	$ 2,822
Weighted average shares of Class A common stock outstanding:(1)
Basic (in shares)	[1]	5,313	4,296	4,968	4,011
Diluted (in shares)	[1]	5,313	4,382	4,968	4,011
Diluted:
Continuing operations (in dollars per share)		$ 12.10	$ 0.45		$ (0.36)
Discontinued operations (in dollars per share)		1.76	0.10		0.70
Diluted net income (loss) attributable to FXCM Inc. (in dollars per share)		13.86	0.55		0.34
Dividends declared per common share (in dollars per share)	[1]	$ 0	$ 0.60	$ 0	$ 1.80
FXCM Holdings LLC
Other Income (Expense)
Net income attributable to non-controlling interest		$ 39,038	$ 1,538	$ (274,650)	$ 1,756
Subsidiaries Excluding FXCM Holdings LLC
Other Income (Expense)
Net income attributable to non-controlling interest		3,667	(1,170)	(39,238)	(5,697)
Common Stock - Class A
Other Income (Expense)
Net income (loss) attributable to FXCM Inc.		73,649	2,392	(448,979)	1,391
Income (loss) from continuing operations attributable to FXCM Inc.		64,302	1,956	(427,909)	(1,431)
Income (loss) from discontinued operations attributable to FXCM Inc.		$ 9,347	$ 436	$ (21,070)	$ 2,822
Weighted average shares of Class A common stock outstanding:(1)
Diluted (in shares)		5,313	4,382	4,968	4,011
Basic:
Continuing operations (in dollars per share)		$ 12.10	$ 0.46	$ (86.13)	$ (0.36)
Discontinued operations (in dollars per share)		1.76	0.10	(4.24)	0.70
Basic net income (loss) attributable to FXCM Inc. (in dollars per share)		13.86	0.56	(90.37)	0.34
Diluted:
Continuing operations (in dollars per share)		12.10	0.45	(86.13)	(0.36)
Discontinued operations (in dollars per share)		1.76	0.10	(4.24)	0.70
Diluted net income (loss) attributable to FXCM Inc. (in dollars per share)		$ 13.86	$ 0.55	$ (90.37)	$ 0.34
[1]	Adjusted to reflect the impact of the one-for-ten reverse stock split that became effective on October 1, 2015, as discussed in Note 1.

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Comprehensive (Loss) Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest [Abstract]
Net income (loss)	$ 116,354	$ 2,760	$ (762,867)	$ (2,550)
Other comprehensive (loss) income
Foreign currency translation loss	(2,239)	(8,366)	(3,121)	(3,643)
Realization of cumulative translation adjustment	0	0	23,407	0
Income tax (benefit) expense	0	(58)	0	108
Other comprehensive (loss) income, net of tax	(2,239)	(8,308)	20,286	(3,751)
Comprehensive income (loss)	114,115	(5,548)	(742,581)	(6,301)
Comprehensive income (loss) attributable to FXCM Inc.	72,203	(2,278)	(436,530)	(752)
FXCM Holdings LLC
Other comprehensive (loss) income
Comprehensive income attributable to non-controlling interest	38,244	(2,085)	(266,808)	163
Subsidiaries Excluding FXCM Holdings LLC
Other comprehensive (loss) income
Comprehensive income attributable to non-controlling interest	$ 3,668	$ (1,185)	$ (39,243)	$ (5,712)

Condensed Consolidated Stateme6

Condensed Consolidated Statement of Stockholders' Equity (Deficit) - 9 months ended Sep. 30, 2015 - USD ($) $ in Thousands	Total	Non-controlling Interests	Retained Earnings (Accumulated Deficit)	Accumulated Other Comprehensive (Loss) Income	Additional Paid-in Capital(1)	[1]	Common Stock - Class ACommon Stock	[1]	Common Stock - Class BCommon Stock
Beginning Balance at Dec. 31, 2014	$ 643,016	$ 358,328	$ 22,379	$ (11,879)	$ 274,139		$ 48		$ 1
Beginning Balance (in shares) at Dec. 31, 2014							4,788,996.4		34
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(762,867)	(313,888)	(448,979)
Other comprehensive income, net of tax	20,286	7,837		12,449
Comprehensive (loss) income	(742,581)	(306,051)	(448,979)	12,449
Equity-based compensation	3,762	1,891			1,871
Exchange of Holdings Units to Class A common stock	0	2,889			(2,895)		$ 6
Exchange of Holdings units to Class A common stock (in shares)							583,670		(6)
Assignment of permitted transferees	0
Assignment of permitted transferees (in shares)									(1)
Stock options issued	321	123			198
Distributions — non-controlling members	(12,166)	(12,166)
Ending Balance at Sep. 30, 2015	$ (107,648)	$ 45,014	$ (426,600)	$ 570	$ 273,313		$ 54		$ 1
Ending Balance (In shares) at Sep. 30, 2015							5,372,666		27
[1]	Adjusted to reflect the impact of the one-for-ten reverse stock split that became effective on October 1, 2015, as discussed in Note 1.

Condensed Consolidated Stateme7

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Cash Flows From Operating Activities
Net income (loss)	$ (762,867)	$ (2,550)
Adjustments to reconcile net loss to net cash used in operating activities
Depreciation and amortization	33,494	40,793
Equity-based compensation	3,644	10,238
Deferred tax expense	188,175	5,051
Goodwill impairment losses	64,378	0
Impairment losses on held for sale assets	27,820	0
Loss on derivative liability — Letter Agreement	254,730	0
Gain on Faros Follow-on Payment	0	(3,672)
Loss on disposal of fixed assets	0	10
Amortization of deferred bond discount	4,180	3,933
Amortization of deferred financing cost	2,351	1,381
Amortization of original issue discount — Credit Agreement	55,373	0
Amortization of issuance fee, deferred financing fee and acquisition costs — Credit Agreement	13,183	0
Loss on equity method investments, net	1,121	910
Gain on business dispositions	(14,427)	0
Transaction costs associated with business dispositions	(6,693)	0
Due to related parties pursuant to tax receivable agreement	(145,224)	(360)
Changes in operating assets and liabilities
Cash and cash equivalents, held for customers	271,231	(140,468)
Restricted time deposits	0	(9,120)
Trading securities	0	(633)
Due from brokers	(8,300)	(27,510)
Accounts receivable, net	2,471	(1,393)
Tax receivable, net	(1,099)	(5,160)
Other assets	(4,092)	(960)
Customer account liabilities	(270,403)	141,519
Accounts payable and accrued expenses	6,379	(13,829)
Other liabilities	6,254	436
Payments for tax receivable agreement	(5,352)	(3,707)
Due to brokers	(16,232)	(7,736)
Securities sold, not yet purchased	(530)	3,815
Foreign currency remeasurement (loss) gain	(682)	345
Net cash used in operating activities	(301,117)	(8,667)
Cash Flows From Investing Activities
Purchases of office, communication and computer equipment, net	(13,571)	(16,320)
Proceeds from sale of office, communication and computer equipment	499	0
Purchase of intangible assets	0	(9,789)
Acquisition of business, net of cash acquired	0	(21,791)
Proceeds from (issuance of) notes receivable	1,500	(1,500)
Proceeds from business dispositions, net of cash	52,155	0
Net cash provided by (used in) investing activities	40,583	(49,400)
Cash Flows From Financing Activities
Distributions to non-controlling members	(12,166)	(4,281)
Contributions from other non-controlling members	0	2,540
Dividends paid	0	(8,258)
Proceeds from exercise of stock options	0	3,608
Common stock repurchases	0	(644)
(Payments on) borrowings under Revolving credit agreement	(25,000)	30,000
Proceeds from the Leucadia Transaction	279,000	0
Payments on borrowings under the Credit Agreement	(107,139)	0
Debt acquisition costs — Credit Agreement	(1,876)	0
Proceeds from issuance of stock options	321	0
Net cash provided by financing activities	133,140	22,965
Effect of foreign currency exchange rate changes on cash and cash equivalents	(1,629)	(3,413)
Net decrease in cash and cash equivalents	(129,023)	(38,515)
Cash and cash equivalents
Beginning of year	338,814	365,245
End of period	209,791	326,730
Supplemental disclosures of cash flow activities
Cash (received) paid for taxes	(135)	407
Cash paid for interest	22,222	2,762
Supplemental disclosure of non-cash investing activities
Exchange of Holdings Units for shares of Class A common stock	2,889	6,328
Notes receivable credited towards consideration for acquisition of business	0	11,942
Notes issued for non-controlling interest	0	8,279
Deferred payment for purchase of intangible assets	6,000	0
Proceeds receivable from business disposition	11,524	0
Supplemental disclosure of non-cash financing activities
Non Cash Change In Redeemable Non Controlling Interests	0	795
Discontinued Operations
Adjustments to reconcile net loss to net cash used in operating activities
Depreciation and amortization	12,359	20,287
Equity-based compensation	1,494	2,447
Deferred tax expense	5,321	263
Goodwill impairment losses	54,865	0
Impairment losses on held for sale assets	27,820	0
Gain on Faros Follow-on Payment	0	3,672
Loss on equity method investments, net	821	606
Gain on business dispositions	(14,427)	0
Transaction costs associated with business dispositions	(6,693)	0
Cash Flows From Investing Activities
Purchases of office, communication and computer equipment, net	(240)	(2,759)
Proceeds from sale of office, communication and computer equipment	499	0
Acquisition of business, net of cash acquired	0	(21,791)
Proceeds from business dispositions, net of cash	$ 52,155	$ 0

Description of Business and Bas

Description of Business and Basis of Presentation	9 Months Ended
	Sep. 30, 2015
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, 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. The remaining businesses are being actively marketed and the Company expects to complete the disposition of these businesses by the first quarter of 2016. 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 On September 29, 2015, the Company filed a Certificate of Amendment to its Amended and Restated Certificate of Incorporation to implement a one-for-ten reverse split of the Corporation's issued and outstanding Class A common stock (the "Reverse Stock Split"), as authorized at a special meeting of stockholders held on September 21, 2015. 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. Total cash payments made by the Company to stockholders in lieu of fractional shares was not material. 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 all periods presented, unless otherwise noted, including reclassifying an amount equal to the reduction in par value of Class A common stock to additional paid-in capital. 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. 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 Company’s condensed consolidated financial statements include the following other significant subsidiaries of Holdings: FXCM Newco, LLC (“Newco”) Forex Capital Markets LLC (“US”) FXCM Asia Limited** (“HK”) Forex Capital Markets Limited (“UK LTD”) FXCM Australia 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 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 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 in 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 Reclassifications of prior period amounts related to discontinued operations as a result of the actual and expected disposals of the Company's interests in certain retail and institutional trading businesses have been made to conform to the current presentation. 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, 2014 . 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	9 Months Ended
	Sep. 30, 2015
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. Other than described below, 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, 2014 . Discontinued Operations As discussed in Note 1, during the first quarter of 2015, management committed to a plan to dispose of certain businesses. The Company determined that these businesses represent components pursuant to ASC 205-20, Presentation of Financial Statements — Discontinued Operations, ("ASC 205-20") and are considered held for sale at the reporting date. When viewed as a whole, the disposal of these components represents a strategic shift as contemplated by ASC 205-20 and the results of operations are reported as discontinued operations for all periods presented (see Note 4). Segments ASC 280, Segment Reporting, establishes standards for reporting information about operating segments. Operating segments are defined as components of an enterprise about which separate financial information is available that is evaluated regularly by the chief operating decision maker, or decision making group, in deciding how to allocate resources and in assessing performance. The guidance defines reportable segments as operating segments that meet certain quantitative thresholds. It was determined in the first quarter of 2015 that as a result of the events of January 15, 2015 described in Note 12, and the decision to sell certain institutional assets, the composition of the Company's previously reported Institutional segment changed significantly, such that the remaining institutional business reported in continuing operations no longer meets the quantitative criteria for separate reporting. In addition, the continuing institutional business shares common management strategies, customer support and trading platforms with the Company's retail business. Accordingly, the Company concluded in the first quarter of 2015 that it operates in a single operating segment. Accounting Pronouncement Adopted in 2015 In April 2014, the FASB issued Accounting Standards Update ("ASU") No. 2014-08, Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360): Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity. Under ASU No. 2014-08, a discontinued operation includes the disposal of a major part of an entity’s operations and financial results such as a major line of business, major geographical area of operations, or major equity method investment. ASU No. 2014-08 also raises the threshold to be a major operation but no longer precludes discontinued operations presentation where there is significant continuing involvement or cash flows with a disposed component of an entity. The guidance expands disclosures to include cash flows where there is significant continuing involvement with a discontinued operation and the pre-tax profit or loss of disposal transactions not reported as discontinued operations. The Company adopted ASU No. 2014-08 on January 1, 2015 on a prospective basis and applied the guidance to its businesses to be disposed of. Adoption of ASU No. 2014-08 had a material impact on the financial statement presentation and disclosure in the Company’s condensed consolidated financial statements and related notes thereto for all periods presented. Recently Issued Accounting Pronouncements 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 using the effective interest method. In August 2015, the FASB issued ASU No. 2015-15, Interest—Imputation of Interest (Subtopic 835-30): Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements—Amendments to SEC Paragraphs Pursuant to Staff Announcement at June 18, 2015 EITF Meeting. ASU No. 2015-15 clarifies the guidance in ASU No. 2015-03 regarding the treatment of debt issuance costs related to line-of-credit arrangements. According to ASU No. 2015-15, the SEC will not object to an entity deferring and presenting debt issuance costs as an asset and subsequently amortizing those costs over the term of the line-of-credit arrangement, regardless of whether there are any outstanding borrowings on the line-of-credit. The guidance in these updates is effective for fiscal years beginning after December 15, 2015 and interim periods within those fiscal years, with early adoption permitted. Upon adoption, an entity is required to apply the new guidance retrospectively to all prior periods presented in the financial statements and provide certain disclosures about the change in accounting principle. The Company expects to adopt this guidance retrospectively beginning January 1, 2016 and is currently evaluating the impact it will have on its 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. ASU No. 2015-02 is effective for fiscal years and interim periods beginning after December 15, 2015, with early adoption permitted. The guidance allows for either a modified retrospective approach or full retrospective application. The Company expects to adopt this guidance beginning January 1, 2016 and is currently evaluating the impact, if any, it 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 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. The updated standard is effective for the Company's first quarter of 2018. The Company is currently evaluating the new guidance and has not yet selected a transition method or determined the impact that adoption of the new standard will have on its consolidated financial statements.

Non-Controlling Interests

Non-Controlling Interests	9 Months Ended
	Sep. 30, 2015
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. Changes in the non-controlling and the Corporation's interests in Holdings for the nine months ended September 30, 2015 are as follows: Controlling Non- Total FXCM Inc. Non- Total Balance as of January 1, 2015 4,788,996 3,445,767 8,234,763 58.1 % 41.9 % 100.0 % Holdings Units acquired by FXCM Inc. related to exchanges of Holdings Units for shares of Class A common stock 583,670 (583,670 ) — 7.1 % (7.1 )% — % Balance as of September 30, 2015 5,372,666 2,862,097 8,234,763 65.2 % 34.8 % 100.0 % * Adjusted to reflect the impact of the one-for-ten reverse stock split that became effective on October 1, 2015, as discussed in Note 1. 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. 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	9 Months Ended
	Sep. 30, 2015
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. The remaining businesses are being actively marketed and the Company expects to complete the disposition of these businesses by the first quarter of 2016. 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 at September 30, 2015 . Accordingly, the assets and liabilities of these businesses have been reclassified to assets and liabilities held for sale in the condensed consolidated statements of financial condition at September 30, 2015 , with similar reclassification of the previously reported amounts. 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 nine months ended September 30, 2015 , with similar reclassification of the previously reported amounts. Completed dispositions On April 1, 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 includes a reversal of $23.4 million of foreign currency translation loss out of accumulated other comprehensive income. The net gain is included in the condensed consolidated statements of operations as a component of Income (loss) from discontinued operations, net of tax for the nine months ended September 30, 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 will be amortized into other income over the nine-month period ending December 31, 2015. The Company recorded other income for these transitional services of $0.8 million and $1.6 million for the three and nine months ended September 30, 2015 , respectively. The terms of the services agreement were finalized during the third quarter of 2015 and provide for the Company to receive a monthly fee for such services beginning January 1, 2016 for a minimum period of nine months. On April 9, 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 nine months ended September 30, 2015 . On September 11, 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 of approximately $12.4 million related to the sale which is included in the condensed consolidated statements of operations as a component of Income (loss) from discontinued operations, net of tax for the three and nine months ended September 30, 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 will be amortized into other income over the nine-month period following the date of sale. For the three months ended September 30, 2015 , the Company recorded $0.1 million of other income for these transitional services. 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. 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 nine months ended September 30, 2015 and 2014 , with amounts in thousands: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Revenues Trading revenue $ 13,386 $ 23,547 $ 60,154 $ 71,282 Interest income 29 118 247 400 Brokerage interest expense (29 ) (25 ) (100 ) (89 ) Net interest revenue — 93 147 311 Other income 1,430 1,122 4,802 8,183 Total net revenues 14,816 24,762 65,103 79,776 Operating Expenses Compensation and benefits 731 4,255 11,532 13,603 Allocation of net income to Lucid members for services provided 2,249 1,483 6,916 6,771 Total compensation and benefits 2,980 5,738 18,448 20,374 Referring broker fees — 263 208 963 Advertising and marketing 15 1,004 736 2,426 Communication and technology 2,061 2,983 6,528 9,238 Trading costs, prime brokerage and clearing fees 4,178 5,627 14,716 18,311 General and administrative 978 2,347 4,215 7,220 Bad debt expense — — 8,408 — Depreciation and amortization — 7,124 12,359 20,287 Goodwill impairment loss — — 54,865 — Total operating expenses 10,212 25,086 120,483 78,819 Operating income (loss) 4,604 (324 ) (55,380 ) 957 Other Expense Loss on equity method investments, net 320 239 821 606 Income (loss) from discontinued operations before income taxes 4,284 (563 ) (56,201 ) 351 Gain on completed dispositions 12,449 — 14,427 — Gain (loss) on classification as held for sale before income taxes 979 — (27,820 ) — Total income (loss) from discontinued operations before income taxes * 17,712 (563 ) (69,594 ) 351 Income tax (benefit) provision (306 ) (206 ) 5,321 282 Income (loss) from discontinued operations, net of tax $ 18,018 $ (357 ) $ (74,915 ) $ 69 * Total income (loss) from discontinued operations before income taxes attributable to FXCM Inc. was $9.1 million and $(19.8) million for the three and nine months ended September 30, 2015 , respectively, and $0.5 million and $3.6 million for the three and nine months ended September 30, 2014 , respectively. The following is a summary of the carrying amounts of the assets and liabilities included as part of discontinued operations as of September 30, 2015 and December 31, 2014 , with amounts in thousands: As of September 30, 2015 December 31, 2014 Assets Cash and cash equivalents $ 23,422 $ 81,927 Cash and cash equivalents, held for customers 67,369 430,496 Restricted time deposits (1) — 8,341 Due from brokers (2) 20,595 27,552 Accounts receivable, net 4,520 3,272 Deferred tax asset — 7,937 Tax receivable 340 1,065 Office, communication and computer equipment, net 5,815 9,166 Goodwill 223,870 284,645 Other intangible assets, net 27,379 42,229 Other assets (3) (4) 12,404 14,819 Loss recognized on classification as held for sale (27,820 ) — Total assets classified as held for sale on the condensed consolidated statements of financial condition $ 357,894 $ 911,449 ** Liabilities Customer account liabilities $ 67,369 $ 430,496 Accounts payable and accrued expenses (5) 12,901 20,850 Due to brokers (6) 21 330 Securities sold, not yet purchased 3,710 4,239 Deferred tax liability — 1,137 Other liabilities 56 151 Total liabilities classified as held for sale on the condensed consolidated statements of financial condition $ 84,057 $ 457,203 ** ____________________________________ ** Amounts as of December 31, 2014 are classified as current and noncurrent on the condensed consolidated statement of financial condition. (1) The time deposits, initially established in July 2014, secured a letter of guarantee on behalf of FXCMJ. The time deposits remained unwithdrawn and were terminated in connection with the sale of FXCMJ in April 2015. (2) Includes as of September 30, 2015 and December 31, 2014 : a) derivative assets, net of $0.1 million and $0.6 million , respectively; b) Unsettled spot FX of $0.4 million and $4.9 million , respectively; c) Unsettled common stock of $3.0 million and $3.7 million , respectively; and d) Excess cash collateral of $17.1 million and $18.3 million , respectively. (3) Includes the Company's exchange memberships, which represent ownership interests and shares owned in the Chicago Mercantile and Intercontinental exchanges and provide the Company with the right to conduct business on the exchanges. 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. In April 2015, the Company sold all of its shares owned in the Intercontinental exchange and recognized a gain of $0.1 million which is included in Income (loss) from discontinued operations, net of tax in the condensed consolidated statements of operations for the nine months ended September 30, 2015 . There were no exchange membership impairments as of September 30, 2015 or December 31, 2014 . The cost of ownership interests and shares owned was $2.7 million and $3.0 million , respectively, at September 30, 2015 and $2.7 million and $3.7 million , respectively, at December 31, 2014 . (4) Includes as of September 30, 2015 and December 31, 2014 the aggregate carrying values of the Company's equity interests in FastMatch and the V3-related LLC of $6.1 million and $6.9 million , respectively. (5) Includes as of both September 30, 2015 and December 31, 2014 amounts due related to the allocation of income to Lucid non-controlling members for services provided of $8.9 million . (6) Comprised of Unsettled spot FX.

Notes Receivable

Notes Receivable	9 Months Ended
	Sep. 30, 2015
Receivables [Abstract]
Notes Receivables	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. Interest income related to the notes receivable was not material for the three months ended September 30, 2015 and 2014 and was $0.1 million for each of the nine months ended September 30, 2015 and 2014. As of September 30, 2015 , there was no reserve against the notes receivable. In May 2014, the Company loaned $1.5 million to a retail FX provider. The amount borrowed was due in 2017 and bore interest at the rate of 15% per annum, due at the end of each calendar quarter. In February 2015, the principal amount plus accrued interest was repaid to the Company.

Equity Method Investments

Equity Method Investments	9 Months Ended
	Sep. 30, 2015
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 $2.8 million and $3.1 million as of September 30, 2015 and December 31, 2014 , 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 for each of the three months ended September 30, 2015 and 2014 and $0.3 million for each of the nine months ended September 30, 2015 and 2014, and is included in Loss on equity method investments, net in the condensed consolidated statements of operations. In December 2012, the Company completed the acquisition of a non-controlling equity interest in FastMatch, an electronic communication network for foreign exchange trading. As the Company holds a 35.4% equity interest 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 holds a 17.26% interest in a firm that delivers investment information to investment professionals. As of September 30, 2015 , the other members of the LLC have not yet consented to the transfer of the 66.3% non-controlling interest to the Company. Until such consent is received, the Company is only entitled to its share of profits, losses and distributions and the Company does not have any right to participate in the management of the business and affairs of the LLC, including participating in major decisions. Accordingly, the Company’s interest is accounted for using the equity method. As discussed in Note 4, V3, including the Company's equity interest in the V3-related LLC, is classified as a discontinued operation. The carrying values of the Company's equity interests in FastMatch and the V3-related LLC are included in assets held for sale in the condensed consolidated statements of financial condition. As of September 30, 2015 and December 31, 2014 , the carrying values of the Company's equity method investments included in assets held for sale were $6.1 million and $6.9 million , respectively. The Company's share of the income or loss of FastMatch and the V3-related LLC is included in Income (loss) from discontinued operations, net of tax in the condensed consolidated statements of operations. Total loss on equity method investments included in Income (loss) from discontinued operations, net of tax was $0.3 million and $0.8 million for the three and nine months ended September 30, 2015 , respectively, and $0.2 million and $0.6 million for the three and nine months ended September 30, 2014 , respectively. The Company did not receive any dividend distributions from its equity method investments during the three and nine months ended September 30, 2015 or 2014 .

Goodwill

Goodwill	9 Months Ended
	Sep. 30, 2015
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 primarily due to a decline in the implied fair value of certain institutional businesses subsequent to January 15, 2015. No additional impairment of goodwill has been identified as of September 30, 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 nine months ended September 30, 2015 . The Company determined the fair value of the reporting units using a discounted cash flow ("DCF") analysis. Determining the fair value requires the exercise of significant judgment, particularly related to the appropriate discount rates, perpetual growth rates and the amount and timing of expected future cash flows. In estimating future cash flows, the Company uses its most recent budgets and business plans, and, when applicable, various growth rates are assumed for years beyond the current business plan period. The Company's DCF analysis uses a market participant weighted-average cost of capital in estimating the discount rate. The inputs to the weighted-average cost of capital calculation include the risk-free rate of return, beta, which is a measure of the level of non-diversifiable risk associated with comparable companies, market equity risk premium and a company-specific risk factor. Changes in goodwill for the nine months ended September 30, 2015 are presented in the following table and reflect the Company's single operating segment, with amounts in thousands: Balance as of January 1, 2015* $ 39,242 Impairment of goodwill (9,513 ) Foreign currency translation and other adjustments (1,073 ) Balance as of September 30, 2015 $ 28,656 * Goodwill of $284.6 million was transferred to assets held for sale at December 31, 2014 (see Note 4).

Other Intangible Assets, net

Other Intangible Assets, net	9 Months Ended
	Sep. 30, 2015
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 September 30, 2015 and December 31, 2014 , with amounts in thousands: September 30, 2015 December 31, 2014 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Finite-lived intangible assets Customer relationships $ 35,460 $ (19,240 ) $ 16,220 $ 29,460 $ (15,040 ) $ 14,420 Foreign currency translation adjustment (1,534 ) 501 (1,033 ) (500 ) 818 318 Total finite-lived intangible assets $ 33,926 $ (18,739 ) $ 15,187 $ 28,960 $ (14,222 ) $ 14,738 Indefinite-lived intangible assets License 600 — 600 600 — 600 Total Other intangible assets, net $ 34,526 $ (18,739 ) $ 15,787 $ 29,560 $ (14,222 ) $ 15,338 In June 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. 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 during the first quarter due to a decline in the implied fair value of certain institutional businesses subsequent to the events of January 15, 2015. No additional impairment of intangible assets has been identified as of September 30, 2015 . The impairment charge is included as a component of amortization expense within discontinued operations for the nine months ended September 30, 2015 . 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 $5.0 million for the three and nine months ended September 30, 2015 , respectively, and $1.2 million and $3.1 million for the three and nine months ended September 30, 2014 , 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 September 30, 2015 is as follows, with amounts in thousands: Year Ending December 31, Remainder of 2015 $ 1,975 2016 7,295 2017 4,055 2018 1,492 2019 370 Thereafter — $ 15,187

Earnings per Share

Earnings per Share	9 Months Ended
	Sep. 30, 2015
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 all 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 nine months ended September 30, 2015 and 2014, 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 each of 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 nine months ended September 30, 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 766,823 for each of the three and nine months ended September 30, 2015 and 103,199 and 764,047 for the three and nine months ended September 30, 2014, respectively, 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 Lucid acquisition 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. The Lucid sellers achieved the Profit Targets for the second anniversary shares during the quarter ended June 30, 2014 and received 300,000 shares in June 2014 which are included in the computation of basic EPS for the three and nine months ended September 30, 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 nine months ended September 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 nine months ended September 30, 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 nine months ended September 30, 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. Certain members of Holdings exchanged 0.2 million and 0.6 million of their Holdings Units during the three and nine months ended September 30, 2015 , respectively, and 14 thousand and 0.1 million of their Holdings Units during the three and nine months ended September 30, 2014 , respectively, 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 September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Basic and diluted net income (loss) per share of Class A common stock: Numerator Income (loss) from continuing operations attributable to FXCM Inc. $ 64,302 $ 1,956 $ (427,909 ) $ (1,431 ) Income (loss) from discontinued operations attributable to FXCM Inc. 9,347 436 (21,070 ) 2,822 Net income (loss) available to holders of Class A common stock 73,649 2,392 (448,979 ) 1,391 Earnings allocated to participating securities — — — — Income (loss) income available to common stockholders $ 73,649 $ 2,392 $ (448,979 ) $ 1,391 Denominator Weighted average shares of Class A common stock (1) 5,313 4,296 4,968 4,011 Add dilutive effect of the following: Weighted average of Lucid's second anniversary shares issued on June 18, 2014 — — — — Stock options and RSUs (1),(2) — 86 — — Convertible note hedges — — — — Warrants — — — — Assumed conversion of Holdings Units for Class A common stock — — — — Dilutive weighted average shares of Class A common stock (1) 5,313 4,382 4,968 4,011 Net income (loss) per share of Class A common stock (1) : Basic: Continuing operations $ 12.10 $ 0.46 $ (86.13 ) $ (0.36 ) Discontinued operations 1.76 0.10 (4.24 ) 0.70 Basic net income (loss) per share of Class A common stock $ 13.86 $ 0.56 $ (90.37 ) $ 0.34 Diluted: Continuing operations $ 12.10 $ 0.45 $ (86.13 ) $ (0.36 ) Discontinued operations 1.76 0.10 (4.24 ) 0.70 Diluted net income (loss) per share of Class A common stock $ 13.86 $ 0.55 $ (90.37 ) $ 0.34 ____________________________________ (1) Adjusted to reflect the impact of the one-for-ten reverse stock split that became effective on October 1, 2015, as discussed in Note 1. (2) No dilutive effect for the three months ended September 30, 2015 therefore zero incremental shares included for the period.

Related Party Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2015
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 September 30, 2015 December 31, 2014 Receivables Advances to Holdings non-controlling members $ 49 $ 196 Accounts receivable — Lucid non-controlling members 15 799 Accounts receivable — equity method investment — 1,468 Advances to employees 212 563 Notes receivable and interest — Lucid non-controlling members 8,131 8,013 Total receivables from related parties $ 8,407 $ 11,039 Payables Guarantee agreement ("Monetary Guaranty") $ — $ 7,078 Employees 806 2,009 Due to Lucid non-controlling members in connection with the allocation of income to Lucid non-controlling members for services provided 8,938 8,876 Accounts payable — equity method investment 448 — Tax receivable agreement — 150,576 Total payables to related parties $ 10,192 $ 168,539 The Company has advanced funds for withholding taxes to several non-controlling members of Holdings. The outstanding balances as of September 30, 2015 and December 31, 2014 , 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 $0.8 million of advances to the Lucid non-controlling members as of December 31, 2014 . Advances to the Lucid non-controlling members were not material as of September 30, 2015 . 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 35.4% 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 and $6.3 million for the three and nine months ended September 30, 2015 , respectively, and $4.1 million and $8.8 million for the three and nine months ended September 30, 2014 , respectively, and are included in Trading revenue in the condensed consolidated statements of operations. Fees paid to FastMatch were nil and $4.3 million for the three and nine months ended September 30, 2015 , respectively, and $3.0 million and $6.2 million for the three and nine months ended September 30, 2014 , respectively, and are reflected as a component of Communication and technology in the condensed consolidated statements of operations. During the nine months ended September 30, 2015, the Company received $0.2 million from FastMatch for occupancy and operational costs, which is included in Other income in the condensed consolidated statements of operations. The Company has also advanced funds for expenses on behalf of FastMatch. At September 30, 2015 and December 31, 2014 , Accounts receivable, net in the condensed consolidated statements of financial condition included a receivable from FastMatch of nil and $1.5 million , respectively, for net amounts due from FastMatch. Accounts payable and accrued expenses at September 30, 2015 and December 31, 2014 included $0.4 million and nil , respectively, of net amounts due to FastMatch. In connection with the sale of FXCMJ, FXCMJ sold $0.5 million of office, communication and computer equipment to FastMatch during the nine months ended September 30, 2015 . The Company has advanced funds to several employees. The outstanding balances as of September 30, 2015 and December 31, 2014 , 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 as of September 30, 2015 and December 31, 2014 . The amount borrowed is due in 2017 and bears interest at the rate of 2% per annum. Interest income related to the notes receivable was not material for the three months ended September 30, 2015 and 2014 and was $0.1 million for each of the nine months ended September 30, 2015 and 2014. UK LTD was party to an arrangement with Global Finance Company (Cayman) Limited (“Global Finance”) and Master Capital Group, S.A.L. (“Master Capital”). A shareholder of the Company beneficially owns more than 90% of the equity of Global Finance and Master Capital. Pursuant to such arrangement, Global Finance and Master Capital were permitted to use the brand name “FXCM” and our technology platform to act as the Company’s 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. These fees and commissions were nil and $0.2 million for the three and nine months ended September 30, 2015 , respectively, and $0.3 million and $0.9 million for the three and nine months ended September 30, 2014 , respectively, and are included in Referring broker fees in the condensed consolidated statements of operations. Effective May 4, 2015, UK LTD terminated the foregoing arrangement with Global Finance and Master Capital. In November 2013, the Company entered into a master guaranty agreement (the “Monetary Guaranty”) with Monetary Credit Group LLC (“Monetary”), a Texas limited liability company, owned by certain directors and shareholders of the Company, including several of the Company’s executive officers. Pursuant to the Monetary Guaranty, Monetary unconditionally guaranteed the obligations of certain counterparties that maintained a margin account with the Company. The Monetary Guaranty required Monetary to maintain a cash collateral account held by the Company equal to the aggregate amount of margin extended to all counterparties covered by the Monetary Guaranty. In exchange for this unconditional guaranty, the Company remitted a fee to Monetary determined on a counterparty by counterparty basis which was agreed upon by the Company, Monetary and the respective counterparty. As of December 31, 2014 , the aggregate amount of margin extended under the Monetary Guaranty was $13.2 million and the Company held cash collateral related to the Monetary Guaranty in the amount $7.1 million , which is included in Cash and cash equivalents, held for customers and Customer account liabilities in the condensed consolidated statements of financial condition. The Company terminated the Monetary Guaranty with Monetary effective January 30, 2015. During the three and nine months ended September 30, 2015 and 2014 , no payments were made by Monetary to the Company to satisfy a guaranteed counterparty obligation. Fees collected from counterparties and subsequently remitted to Monetary by the Company under the Monetary Guaranty were nil and not material for the three and nine months ended September 30, 2015 , respectively, and $0.3 million and $0.5 million for the three and nine months ended September 30, 2014 , respectively, and are included in Referring broker fees in the condensed consolidated statements of operations. Amounts due related to the allocation of income to Lucid non-controlling members for services provided were $8.9 million as of both September 30, 2015 and December 31, 2014 , respectively, and are included in Current liabilities held for sale on the condensed consolidated statement 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 nine months ended September 30, 2015 and 2014 , certain members of Holdings exchanged 0.6 million and 0.1 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 $146.3 million and $150.6 million as of September 30, 2015 and December 31, 2014 , 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 September 30, 2015 , the Corporation continues to believe it will not benefit from the tax deduction and the contingent liability remains zero. During the nine months ended September 30, 2015 and 2014 , payments of $5.4 million and $3.7 million , respectively, were made pursuant to the tax receivable agreement.

Net Capital Requirements

Net Capital Requirements	9 Months Ended
	Sep. 30, 2015
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 September 30, 2015 and December 31, 2014 , with amounts in millions: As of September 30, 2015 US UK LTD Australia ODL FSL Lucid LLP Capital $ 48.3 $ 78.4 $ 3.2 $ 9.1 $ 5.5 $ 12.2 Minimum capital requirement 28.9 30.0 0.7 1.3 0.9 2.0 Excess capital $ 19.4 $ 48.4 $ 2.5 $ 7.8 $ 4.6 $ 10.2 As of December 31, 2014 US UK LTD HK Australia ODL FSL FXCMJ Lucid LLP Faros Capital $ 69.5 $ 101.6 $ 31.2 $ 3.0 $ 25.5 $ 40.2 $ 36.3 $ 22.8 $ 0.4 Minimum capital requirement 30.0 29.2 14.8 0.8 3.0 5.2 6.3 3.8 — Excess capital $ 39.5 $ 72.4 $ 16.4 $ 2.2 $ 22.5 $ 35.0 $ 30.0 $ 19.0 $ 0.4

Leucadia Transaction

Leucadia Transaction	9 Months Ended
	Sep. 30, 2015
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. On January 28, 2015, the Company issued a press release announcing a decision to forgive approximately 90% of the clients who incurred debit balances in certain jurisdictions as a result of the SNB announcement on January 15, 2015. The Company notified certain clients (such as institutional, high net worth and experienced traders who generally maintain higher account balances) that sustained debit balances as a result of the market events on January 15, 2015, that they will be required to pay their debit balances, pursuant to the terms of the Company's master trading agreements. This group represents approximately 10% of clients who incurred debit balances, but comprises over 60% of the total debit balances owed. The Company made the decision in the second quarter of 2015 to forgive the debit balances of additional retail clients, increasing the total debit balance forgiveness to approximately 97% of clients, and to return certain recoveries totaling approximately $0.1 million , which is reflected in Bad debt expense in the condensed consolidated statements of operations. Approximately 3% of clients remain who were previously notified that they will be required to pay their debit balances, which comprises approximately 11% of the total debit balances owed as a result of the events on January 15, 2015. In light of the numerous uncertainties associated with collection options, the Company cannot provide any assurance that it will be successful in recovering any portion of the remaining clients' debit balances. Through the nine months ended September 30, 2015 , the Company has recovered $9.4 million . Bad debt expense from continuing operations in the condensed consolidated statements of operations for the three and nine months ended September 30, 2015 includes net expense of nil and $257.3 million , respectively, related to the debit balances. Bad debt expense for the nine months ended September 30, 2015 includes the $0.1 million reversal of recoveries noted above as well as $0.3 million reversal of recovery as payment for an option agreement entered into with a customer in the second quarter of 2015 as part of a negative equity balance settlement (see Note 17). Bad debt expense from continuing operations for the nine months ended September 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 nine months ended September 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. 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 September 30, 2015 , the Company has paid $107.1 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 nine months ended September 30, 2015 . At September 30, 2015 , 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 $8.70 (after giving effect to the one-for-ten reverse stock split). This valuation approach incorporates an option pricing model for the allocation of enterprise value between the derivative liability, common stock and convertible debt. Consistent with the prior quarter, the Company believes, as of the valuation date, common stock investors have taken into account the dilutive impact of the Letter Agreement. At the March 31, 2015 valuation date, the Company believed the common stock price had not fully reflected the dilutive impact of the Letter Agreement. As a result, in estimating the fair value of the derivative liability at March 31, 2015, the Company used a combination of valuation approaches that were weighted more significantly toward indications of enterprise value based on the income and market approaches, which resulted in a model-derived implied common stock value of $11.10 (after giving effect to the one-for-ten reverse stock split). As of September 30, 2015 , the fair value of the derivative liability resulting from the Letter Agreement was estimated at $348.5 million , 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 at September 30, 2015 resulted in a gain of $137.6 million for the three months ended September 30, 2015. For the nine months ended September 30, 2015 , the Company recognized a loss on the derivative liability of $254.1 million . The changes in the estimated fair value of the derivative liability are recorded in Gain (loss) on derivative liability — Letter Agreement 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 $55.2 million (decrease of approximately $61.1 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 $35.3 million (increase of approximately $40.9 million ) in this valuation, assuming no other change in any other factors considered. The balance of the Credit Agreement as of September 30, 2015 , was as follows, with amounts in thousands: As of September 30, 2015 Debt principal $ 202,861 Original issue discount (46,171 ) Discount — issuance fee (6,605 ) Deferred financing fee (4,755 ) Debt — net carrying value $ 145,330 Interest expense related to the Credit Agreement, included in Interest on borrowings in the condensed consolidated statements of operations for the three and nine months ended September 30, 2015 , consists of the following, with amounts in thousands: Three Months Ended September 30, 2015 Nine Months Ended September 30, 2015 Contractual interest $ 7,301 $ 20,202 Deferred interest 734 5,586 Amortization of original issue discount 14,686 55,373 Amortization of issuance fee discount 1,969 7,287 Amortization of deferred financing fee 1,417 5,245 Amortization of debt acquisitions costs 176 651 Total interest expense — Credit Agreement $ 26,283 $ 94,344 The Company records deferred interest for the difference between the current contractual rate based on the loan terms and the weighted average rate through maturity. 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 $2.0 million and $7.3 million for the three and nine months ended September 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 nine months ended September 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 for the three and nine months ended September 30, 2015 was $0.2 million and $0.6 million , 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 nine months ended September 30, 2015 . Unamortized Credit Agreement issuance costs at September 30, 2015 were $0.6 million and are included in Other assets in 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 $1.4 million and $5.2 million for the three and nine months ended September 30, 2015 , respectively. The deferred financing fee was paid on April 1, 2015.

Debt

Debt	9 Months Ended
	Sep. 30, 2015
Debt Disclosure [Abstract]
Debt	Debt Revolving Credit Agreement On December 19, 2011, Holdings entered into a credit agreement ("Revolving Credit Agreement") with a syndicate of financial institutions. At December 31, 2014 , Holdings' outstanding balance under the Revolving Credit Agreement was $25.0 million . In connection with the Leucadia Transaction, the outstanding balance 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 nine months ended September 30, 2015 , respectively, and $0.4 million and $1.2 million for the three and nine months ended September 30, 2014 , respectively. During the three and nine months ended September 30, 2015 , the weighted average dollar amount of borrowings related to the Revolving Credit Agreement was nil and $1.7 million , respectively, and the weighted average interest rates were nil and 2.92% , respectively. During the three and nine months ended September 30, 2014 , the weighted average dollar amount of borrowings related to the Revolving Credit Agreement was $27.7 million and $37.5 million , respectively, and the weighted average interest rates were 2.90% and 2.68% , 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 balances of the liability and equity components as of September 30, 2015 and December 31, 2014 , were as follows, with amounts in thousands: As of September 30, 2015 December 31, 2014 Liability component — principal $ 172,500 $ 172,500 Deferred bond discount (16,742 ) (20,922 ) Liability component — net carrying value $ 155,758 $ 151,578 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 September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Stated coupon rate $ 970 $ 970 $ 2,911 $ 2,911 Amortization of deferred bond discount 1,419 1,335 4,180 3,932 Amortization of debt issuance cost 302 302 907 907 Total interest expense — Convertible Notes $ 2,691 $ 2,607 $ 7,998 $ 7,750 The Company incurred $6.0 million of Convertible Notes issuance cost. Unamortized Convertible Notes issuance cost was $3.2 million and $4.1 million at September 30, 2015 and December 31, 2014 , respectively, and is included in Other assets on the condensed consolidated statements of financial condition.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2015
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. Based on the Company’s investigation to date, FXCM has 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 received an email from a hacker claiming to have unlawful access to customer information. The Company immediately notified the FBI of this threat and is cooperating with the FBI. The Company also immediately launched a full investigation, working with a leading cybersecurity firm, to investigate the cybersecurity incident and protect customer information. The Company, along with the leading cybersecurity firm, is conducting an extensive forensic investigation to determine the scope of the incident and identify affected customers. While this cybersecurity incident did not have a material impact on the business, cash flows, financial condition and results of operations for the three and nine months ended September 30, 2015, the Company has incurred expenses subsequent to the cybersecurity incident to investigate and remediate this matter and expects to 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 the quarter ended September 30, 2015, the Company has incurred $0.2 million of costs related to investigative and other professional services, costs of communications with customers and remediation activities associated with the incident. 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. Guaranty In July 2015, the Company entered into a continuing 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 agrees to indemnify Citibank, N.A. for any liabilities and other amounts that become due and payable by FastMatch for services provided by Citibank N.A. as the intermediating counterparty for trading transactions executed on the FastMatch platform. There is no limitation to the maximum potential future payments under the Guaranty. FastMatch has agreed to indemnify the Company for any losses suffered, however there is no assurance that the Company will be able to recover any or all of the losses under such indemnity. The Guaranty terminated on November 1, 2015, however, it was re-executed on the same terms and will expire on March 1, 2016. The Company cannot reasonably estimate the maximum potential amount of future payments under the Guaranty and the related provisions described above because it cannot predict when and under what circumstances these provisions may be triggered. There is no liability recorded for the Guaranty on the condensed consolidated statements of financial condition at September 30, 2015 . Other The Company holds an interest in an inactive entity that formerly provided online FX educational services (“Online Courses”). Online Courses meets the definition of a VIE under ASC 810 and the Company was considered the primary beneficiary. The members who owned the remaining interest in Online Courses had put options to sell their interest to the Company upon a change in control of Holdings. A change in control occurs when the number of Holdings Units held by unit holders as of the date of the Online Courses operating agreement, November 17, 2008, cease to make up at least 50% of the voting or vested economic interest securities of Holdings. The change in control occurred during the third quarter of 2013. Under U.S. GAAP, the value of the put options is recognized upon both the change in control and the exercise of the put options. In April 2014 and September 2014, 37% percent and 63% percent, respectively, of the put options were exercised and Holdings remitted payments in the amount of $1.3 million and $2.3 million , respectively. Based on the status (inactive and no assets) of Online Courses, the put option payments resulted in a charge to earnings for the three and nine months ended September 30, 2014 of $2.3 million and $3.6 million , respectively, which is included in General and administrative expense in the condensed consolidated statements of operations.

Derivative Financial Instrument

Derivative Financial Instruments	9 Months Ended
	Sep. 30, 2015
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, Balance Sheet ("ASC 210") and ASC 815. The Company enters into futures contracts and 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 included in the Company's businesses to be disposed of as of September 30, 2015 . 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 September 30, 2015 and December 31, 2014 . 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 September 30, 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 (1) $ 4,429 $ 76,440 $ — $ — CFD contracts Due from/Due to brokers (2) 134 181,480 9 35,352 Futures contracts Due from/Due to brokers and Current assets/liabilities held for sale (1), (2) 2,457 402,962 8,661 1,109,179 Total derivatives, gross $ 7,020 $ 660,882 $ 8,670 $ 1,144,531 Netting agreements and cash collateral netting (6,654 ) (8,670 ) Total derivatives, net $ 366 $ — ____________________________________ (1) As of September 30, 2015 , the aggregate fair values of derivative assets and liabilities, gross related to discontinued operations is $6.7 million and $8.6 million , respectively. These amounts are offset by netting agreements and cash collateral netting of $6.6 million and $8.6 million , respectively. (2) As of September 30, 2015 , the aggregate fair values of derivative assets and liabilities, gross related to continuing operations is $0.3 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. As of December 31, 2014 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) $ 10,724 $ 95,498 $ 11,422 $ 81,053 Futures contracts Due from/Due to brokers and Current assets/liabilities held for sale (3) (4) 332,346 3,617,128 352,703 3,627,562 OTC options Current liabilities held for sale (3) — — 1,086 1,086 Total derivatives, gross $ 343,070 $ 3,712,626 $ 365,211 $ 3,709,701 Netting agreements and cash collateral netting (342,467 ) (353,543 ) Total derivatives, net $ 603 $ 11,668 ____________________________________ (3) As of December 31, 2014 , the aggregate fair values of derivative assets and liabilities, gross related to discontinued operations is $342.7 million and $353.1 million , respectively. These amounts are offset by netting agreements and cash collateral netting of $342.1 million and $353.1 million , respectively. (4) As of December 31, 2014 , the aggregate fair value of derivative assets and liabilities, gross related to continuing operations is $0.4 million and $12.1 million , respectively. These amounts are offset by netting agreements and cash collateral netting of $0.4 million and $0.4 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 nine months ended September 30, 2015 and 2014 , with amounts in thousands: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Exchange traded options (5) $ 6,049 $ (5,916 ) $ 5,320 $ 14,002 CFD contracts (6) 3,216 — (2,131 ) — Futures contracts (7) 5,053 (21,181 ) 43,115 (7,428 ) OTC options (5) — (777 ) 1,086 (394 ) Total $ 14,318 $ (27,874 ) $ 47,390 $ 6,180 ____________________________________ (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. (7) The portion included in Income (loss) from continuing operations in the condensed consolidated statements of operations is $7.5 million and $25.8 million for the three and nine months ended September 30, 2015 , respectively, and $(33.0) million and $(12.2) million for the three and nine months ended September 30, 2014 , respectively.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2015
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 September 30, 2015 Level 1 Level 2 Level 3 Counterparty and Cash Collateral Netting Total Financial Assets: Derivative assets: Exchange traded options $ 4,429 $ — $ — $ — $ 4,429 CFD contracts — 134 — — 134 Futures contracts 2,457 — — — 2,457 Netting — — — (6,654 ) (6,654 ) Total derivative assets (1) 6,886 134 — (6,654 ) 366 Total assets $ 6,886 $ 134 $ — $ (6,654 ) $ 366 Financial Liabilities: Customer account liabilities (2) $ — $ 780,573 $ — $ — $ 780,573 Derivative liabilities: CFD contracts — 9 — — 9 Futures contracts 8,661 — — — 8,661 Netting — — — (8,670 ) (8,670 ) Total derivative liabilities (1) 8,661 9 — (8,670 ) — Securities sold, not yet purchased (3) 3,710 — — — 3,710 Letter Agreement — — 348,531 — 348,531 Total liabilities $ 12,371 $ 780,582 $ 348,531 $ (8,670 ) $ 1,132,814 Fair Value Measurements on a Recurring Basis As of December 31, 2014 Level 1 Level 2 Level 3 Counterparty and Cash Collateral Netting Total Financial Assets: Trading securities (3) $ 26 $ — $ — $ — $ 26 Derivative assets: Exchange traded options 10,724 — — — 10,724 Futures contracts 332,346 — — — 332,346 Netting — — — (342,467 ) (342,467 ) Total derivative assets (1) 343,070 — — (342,467 ) 603 Total assets $ 343,096 $ — $ — $ (342,467 ) $ 629 Financial Liabilities: Customer account liabilities (2) $ — $ 1,331,723 $ — $ — $ 1,331,723 Derivative liabilities: Exchange traded options 11,422 — — — 11,422 Futures contracts 352,703 — — — 352,703 OTC options — 1,086 — — 1,086 Netting — — — (353,543 ) (353,543 ) Total derivative liabilities (1) 364,125 1,086 — (353,543 ) 11,668 Securities sold, not yet purchased (3) 4,239 — — — 4,239 Total liabilities $ 368,364 $ 1,332,809 $ — $ (353,543 ) $ 1,347,630 ____________________________________ (1) Relates to continuing and discontinued operations. See Note 15 for details of the classification of amounts on the condensed consolidated statements of financial position. (2) Relates to continuing and discontinued operations. See Note 4 for amount classified as liabilities held for sale on the condensed consolidated statements of financial position. (3) Relates to discontinued operations. Amounts classified as held for sale on the condensed consolidated statements of financial position (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. Trading Securities Equity securities that the Company purchased with the intent to sell in the near-term are classified as trading securities. These trading securities are reported at their fair value based on the quoted market prices of the securities in active markets. Changes in fair value of equity securities from trading activity are recorded in Income (loss) from discontinued operations, net of tax in the condensed consolidated statements of operations. 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, summarized in the following table, are considered more relevant in the analysis and are given a higher weighting in the overall fair value determination (see Note 12). As of September 30, 2015 Valuation Technique Significant Unobservable Input(s) Input Option-Pricing Method Term (years) 2.7 Volatility 58.9 % Risk-free rate 0.8 % Dividend yield — % Reliance placed on public indication of value 100.0 % The derivative liability, 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 $35.3 million (increase of approximately $40.9 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 September 30, 2015 Fair Value Measurements using: Carrying Value Fair Value Level 1 Level 2 Level 3 Financial Assets: Due from brokers — unsettled spot FX (4) $ 24,219 $ 24,219 $ — $ 24,219 $ — Due from brokers — unsettled common stock (5) 3,054 3,054 — 3,054 — Due from brokers — excess cash collateral (5) 16,963 16,963 — 16,963 — Equity method investments (4) 8,887 18,359 — — 18,359 Notes receivable 7,881 7,881 — — 7,881 Exchange memberships (5) 5,770 6,325 — 6,325 — Total assets $ 66,774 $ 76,801 $ — $ 50,561 $ 26,240 Financial Liabilities: Due to brokers — unsettled spot FX (4) $ 81 $ 81 $ — $ 81 $ — Senior convertible notes 155,758 129,377 — 129,377 — Credit Agreement 145,330 202,861 — — 202,861 Total liabilities $ 301,169 $ 332,319 $ — $ 129,458 $ 202,861 As of December 31, 2014 Fair Value Measurements using: Carrying Value Fair Value Level 1 Level 2 Level 3 Financial Assets: Restricted time deposits (5) $ 8,341 $ 8,341 $ — $ 8,341 $ — Due from brokers — unsettled spot FX (4) 14,635 14,635 — 14,635 — Due from brokers — unsettled common stock (5) 3,730 3,730 — 3,730 — Due from brokers — excess cash collateral (5) 18,330 18,330 — 18,330 — Equity method investments (4) 10,007 17,199 — — 17,199 Notes receivable 9,381 9,381 — — 9,381 Exchange memberships (5) 6,429 7,802 — 7,802 — Total assets $ 70,853 $ 79,418 $ — $ 52,838 $ 26,580 Financial Liabilities: Due to brokers — unsettled spot FX (4) 4,645 4,645 — 4,645 — Revolving credit agreement 25,000 25,000 — 25,000 — Senior convertible notes 151,578 147,266 — 147,266 — Total liabilities $ 181,223 $ 176,911 $ — $ 176,911 $ — ____________________________________ (4) Relates to continuing and discontinued operations. See Note 4 for amounts classified as held for sale on the condensed consolidated statements of financial condition. (5) Relates 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. 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. Restricted Time Deposits Restricted time deposits consist of pledged time deposits with original maturities of three months and one year and for which use is contractually restricted. Restricted time deposits are recorded at cost, which approximates fair value. 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. Revolving Credit Agreement Balances due under the Revolving Credit Agreement were carried at contracted amounts which approximated fair value based on the short term nature of the borrowing and the variable interest rate. The following table reconciles the opening and ending balance of the recurring fair value measurement categorized as Level 3, which is included in the condensed consolidated statements of financial condition as of September 30, 2015 , and identifies the total losses the Company recognized during the nine months ended September 30, 2015 , with amounts in thousands: As of September 30, 2015 Beginning Balance Additions Net Unrealized Loss Ending balance Letter Agreement $ — $ 94,436 $ 254,095 $ 348,531 Total Level 3 liabilities $ — $ 94,436 $ 254,095 $ 348,531 The net unrealized loss of $254.1 million is included in Gain (loss) on derivative liability — Letter Agreement in the condensed consolidated statements of operations for the nine months ended September 30, 2015 . There were no transfers into or out of Level 1, 2 or 3 of the fair value hierarchy during the three and nine months ended September 30, 2015 .

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2015
Equity [Abstract]
Stockholders' Equity	Stockholders' Equity Stockholder Rights Plan On January 28, 2015, the Corporation's Board of Directors approved the adoption of a stockholder rights plan (the "Rights Plan") and declared a dividend distribution of one right on each outstanding share of the Corporation's Class A common stock. Under the terms of the Rights Plan, rights to purchase one one-hundredth (1/100) of a share of a new Series A Junior Participating Preferred Stock of the Corporation (the "Rights") at a price of $112.00 per one one-hundredth (1/100) of a share were issued at the rate of one right for each outstanding share of the Corporation's common stock held of record on February 9, 2015 (after giving effect to the one-for-ten reverse stock split). Under the terms of the Rights Plan, the Rights will initially trade together with the Corporation's Class A common stock and will not be exercisable. In the absence of further action by the Corporation's Board of Directors, the Rights will generally become exercisable and allow the holder to acquire shares of the Corporation's common stock at a discounted price if (a) a person or group acquires beneficial ownership of 10% or more of the Corporation's outstanding common stock or (b) any person or group commences a tender or exchange offer, the consummation of which would result in such person or group acquiring beneficial ownership of 10% or more of the Corporation's outstanding common stock. Rights held by the person or group triggering the rights will become void and will not be exercisable. As of September 30, 2015 , the Company is not aware of the occurrence of any events that would trigger the exercise of the Rights under the Rights Plan. The issuance of Rights is not a taxable event, did not affect the reported financial condition or results of operations, including earnings per share, of the Corporation and did not change the manner in which the Corporation's Class A common stock is currently traded. 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. Reverse Stock Split On September 29, 2015, the Company filed a Certificate of Amendment to its Amended and Restated Certificate of Incorporation to implement a one-for-ten reverse split of the Corporation's issued and outstanding Class A common stock (the "Reverse Stock Split"), as authorized at a special meeting of stockholders held on September 21, 2015. The Reverse Stock Split became effective at the opening of trading 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 periods presented, unless otherwise noted, including reclassifying an amount equal to the reduction in par value of Class A common stock to additional paid-in capital.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2015
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 0.3% for the three months ended September 30, 2015 compared to 30.2% for the three months ended September 30, 2014 . The Company's effective tax rate was (35.9)% for the nine months ended September 30, 2015 compared to (109.0)% for the nine months ended September 30, 2014 . The negative tax rate for the nine months ended September 30, 2015 and 2014 reflects the recording of a tax provision on a book loss. The decrease in the effective tax rate for the three months ended September 30, 2015 compared to the same period in 2014 was due predominately to reversing valuation allowance in the current quarter against tax liability associated with the taxable income. During the quarter ended September 30, 2015, similar to the quarters ended June 30, 2015 and March 31, 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. The tax rate for the nine months ended September 30, 2015 is principally the result of recording valuation allowance on our deferred tax assets. The tax rate for the nine months ended September 30, 2014 was principally the result of providing taxes for jurisdictions with higher tax rates against the benefit for losses with a lower rate and recording valuation allowance against foreign tax credit carryforwards. During the nine months ended September 30, 2015 , 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"). During the first quarter of 2014, the IRS concluded the audit of the Company's 2011 federal tax return with no adjustment to the tax owed. Certain of the Company’s UK subsidiaries are currently subject to examination.

Litigation

Litigation	9 Months Ended
	Sep. 30, 2015
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 2014, the trial court, and subsequently the Texas court of appeals, denied US's motions to compel arbitration in New York based on the mandatory forum selection clause and the arbitration agreement in its Client Agreement with Revelation. In February 2015, US filed for review of these decisions in the Texas Supreme Court. The Texas Supreme Court has ordered the parties to file briefs on the merits. On June 15, 2015, that same equity receiver filed a Complaint in Texas federal court, seeking $2.0 million , plus interest, and attorneys’ fees, based on allegations that that amount represents the net fraudulent transfers from Revelation to US under New York law. On September 30, 2015, the parties filed a motion to stay the proceedings pending the conclusion of an arbitration before the National Futures Association (“NFA”) on these claims. In February 2014, UK LTD and FSL entered into a settlement with the FCA following an investigation into trade execution practices of UK LTD and FSL in the period from 2006 to 2010, as well as a breach of notification obligations to the FCA. UK LTD and FSL agreed to pay (a) restitution to affected clients up to $9.9 million ; and (b) a financial penalty of GBP 4.0 million (USD 6.6 million ), together with any unclaimed restitution. In June 2014 and February 2015, UK LTD and FSL paid an additional $1.8 million and $0.7 million , respectively, in restitution to affected clients. 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. HK continues to comply with information requests from SFC. In July 2014, US settled a complaint brought by the NFA relating to charges of doing business with an unregistered entity and for failing to submit certain trade data reports and was fined $0.2 million . In September 2015, US settled a related 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 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. The Court is currently in the process of selecting a lead plaintiff among several applicants. The Company intends to vigorously defend the allegations in the 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. We believe the estimate of the aggregate range of possible loss in excess of accrued liabilities for such matters is between nil and $6.0 million as of September 30, 2015 . 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	9 Months Ended
	Sep. 30, 2015
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events The Company has evaluated its subsequent events through the filing date of this Form 10-Q. On September 29, 2015, the Company filed a Certificate of Amendment to its Amended and Restated Certificate of Incorporation to implement a one-for-ten reverse split of the Corporation's issued and outstanding Class A common stock (the "Reverse Stock Split"), as authorized at a special meeting of stockholders held on September 21, 2015. 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. Total cash payments made by the Company to stockholders in lieu of fractional shares was not material.

Significant Accounting Polici28

Significant Accounting Policies and Estimates (Policies)	9 Months Ended
	Sep. 30, 2015
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. 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 Company’s condensed consolidated financial statements include the following other significant subsidiaries of Holdings: FXCM Newco, LLC (“Newco”) Forex Capital Markets LLC (“US”) FXCM Asia Limited** (“HK”) Forex Capital Markets Limited (“UK LTD”) FXCM Australia 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 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 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 in 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 Reclassifications of prior period amounts related to discontinued operations as a result of the actual and expected disposals of the Company's interests in certain retail and institutional trading businesses have been made to conform to the current presentation.
Discontinued Operations	Discontinued Operations As discussed in Note 1, during the first quarter of 2015, management committed to a plan to dispose of certain businesses. The Company determined that these businesses represent components pursuant to ASC 205-20, Presentation of Financial Statements — Discontinued Operations, ("ASC 205-20") and are considered held for sale at the reporting date. When viewed as a whole, the disposal of these components represents a strategic shift as contemplated by ASC 205-20 and the results of operations are reported as discontinued operations for all periods presented (see Note 4).
Segments	Segments ASC 280, Segment Reporting, establishes standards for reporting information about operating segments. Operating segments are defined as components of an enterprise about which separate financial information is available that is evaluated regularly by the chief operating decision maker, or decision making group, in deciding how to allocate resources and in assessing performance. The guidance defines reportable segments as operating segments that meet certain quantitative thresholds. It was determined in the first quarter of 2015 that as a result of the events of January 15, 2015 described in Note 12, and the decision to sell certain institutional assets, the composition of the Company's previously reported Institutional segment changed significantly, such that the remaining institutional business reported in continuing operations no longer meets the quantitative criteria for separate reporting. In addition, the continuing institutional business shares common management strategies, customer support and trading platforms with the Company's retail business. Accordingly, the Company concluded in the first quarter of 2015 that it operates in a single operating segment.
New Accounting Pronouncements	Accounting Pronouncement Adopted in 2015 In April 2014, the FASB issued Accounting Standards Update ("ASU") No. 2014-08, Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360): Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity. Under ASU No. 2014-08, a discontinued operation includes the disposal of a major part of an entity’s operations and financial results such as a major line of business, major geographical area of operations, or major equity method investment. ASU No. 2014-08 also raises the threshold to be a major operation but no longer precludes discontinued operations presentation where there is significant continuing involvement or cash flows with a disposed component of an entity. The guidance expands disclosures to include cash flows where there is significant continuing involvement with a discontinued operation and the pre-tax profit or loss of disposal transactions not reported as discontinued operations. The Company adopted ASU No. 2014-08 on January 1, 2015 on a prospective basis and applied the guidance to its businesses to be disposed of. Adoption of ASU No. 2014-08 had a material impact on the financial statement presentation and disclosure in the Company’s condensed consolidated financial statements and related notes thereto for all periods presented. Recently Issued Accounting Pronouncements 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 using the effective interest method. In August 2015, the FASB issued ASU No. 2015-15, Interest—Imputation of Interest (Subtopic 835-30): Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements—Amendments to SEC Paragraphs Pursuant to Staff Announcement at June 18, 2015 EITF Meeting. ASU No. 2015-15 clarifies the guidance in ASU No. 2015-03 regarding the treatment of debt issuance costs related to line-of-credit arrangements. According to ASU No. 2015-15, the SEC will not object to an entity deferring and presenting debt issuance costs as an asset and subsequently amortizing those costs over the term of the line-of-credit arrangement, regardless of whether there are any outstanding borrowings on the line-of-credit. The guidance in these updates is effective for fiscal years beginning after December 15, 2015 and interim periods within those fiscal years, with early adoption permitted. Upon adoption, an entity is required to apply the new guidance retrospectively to all prior periods presented in the financial statements and provide certain disclosures about the change in accounting principle. The Company expects to adopt this guidance retrospectively beginning January 1, 2016 and is currently evaluating the impact it will have on its 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. ASU No. 2015-02 is effective for fiscal years and interim periods beginning after December 15, 2015, with early adoption permitted. The guidance allows for either a modified retrospective approach or full retrospective application. The Company expects to adopt this guidance beginning January 1, 2016 and is currently evaluating the impact, if any, it 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 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. The updated standard is effective for the Company's first quarter of 2018. The Company is currently evaluating the new guidance and has not yet selected a transition method or determined the impact that adoption of the new standard will have on its consolidated financial statements.

Description of Business and B29

Description of Business and Basis of Presentation (Tables)	9 Months Ended
	Sep. 30, 2015
Accounting Policies [Abstract]
Schedule of Significant Subsidiaries	The Company’s condensed consolidated financial statements include the following other significant subsidiaries of Holdings: FXCM Newco, LLC (“Newco”) Forex Capital Markets LLC (“US”) FXCM Asia Limited** (“HK”) Forex Capital Markets Limited (“UK LTD”) FXCM Australia 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”)

Non-Controlling Interests (Tabl

Non-Controlling Interests (Tables)	9 Months Ended
	Sep. 30, 2015
Noncontrolling Interest [Abstract]
Changes in the Non-controlling and the Corporation's interest in Holdings	Changes in the non-controlling and the Corporation's interests in Holdings for the nine months ended September 30, 2015 are as follows: Controlling Non- Total FXCM Inc. Non- Total Balance as of January 1, 2015 4,788,996 3,445,767 8,234,763 58.1 % 41.9 % 100.0 % Holdings Units acquired by FXCM Inc. related to exchanges of Holdings Units for shares of Class A common stock 583,670 (583,670 ) — 7.1 % (7.1 )% — % Balance as of September 30, 2015 5,372,666 2,862,097 8,234,763 65.2 % 34.8 % 100.0 %

Discontinued Operations (Tables

Discontinued Operations (Tables)	9 Months Ended
	Sep. 30, 2015
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 nine months ended September 30, 2015 and 2014 , with amounts in thousands: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Revenues Trading revenue $ 13,386 $ 23,547 $ 60,154 $ 71,282 Interest income 29 118 247 400 Brokerage interest expense (29 ) (25 ) (100 ) (89 ) Net interest revenue — 93 147 311 Other income 1,430 1,122 4,802 8,183 Total net revenues 14,816 24,762 65,103 79,776 Operating Expenses Compensation and benefits 731 4,255 11,532 13,603 Allocation of net income to Lucid members for services provided 2,249 1,483 6,916 6,771 Total compensation and benefits 2,980 5,738 18,448 20,374 Referring broker fees — 263 208 963 Advertising and marketing 15 1,004 736 2,426 Communication and technology 2,061 2,983 6,528 9,238 Trading costs, prime brokerage and clearing fees 4,178 5,627 14,716 18,311 General and administrative 978 2,347 4,215 7,220 Bad debt expense — — 8,408 — Depreciation and amortization — 7,124 12,359 20,287 Goodwill impairment loss — — 54,865 — Total operating expenses 10,212 25,086 120,483 78,819 Operating income (loss) 4,604 (324 ) (55,380 ) 957 Other Expense Loss on equity method investments, net 320 239 821 606 Income (loss) from discontinued operations before income taxes 4,284 (563 ) (56,201 ) 351 Gain on completed dispositions 12,449 — 14,427 — Gain (loss) on classification as held for sale before income taxes 979 — (27,820 ) — Total income (loss) from discontinued operations before income taxes * 17,712 (563 ) (69,594 ) 351 Income tax (benefit) provision (306 ) (206 ) 5,321 282 Income (loss) from discontinued operations, net of tax $ 18,018 $ (357 ) $ (74,915 ) $ 69 * Total income (loss) from discontinued operations before income taxes attributable to FXCM Inc. was $9.1 million and $(19.8) million for the three and nine months ended September 30, 2015 , respectively, and $0.5 million and $3.6 million for the three and nine months ended September 30, 2014 , respectively. The following is a summary of the carrying amounts of the assets and liabilities included as part of discontinued operations as of September 30, 2015 and December 31, 2014 , with amounts in thousands: As of September 30, 2015 December 31, 2014 Assets Cash and cash equivalents $ 23,422 $ 81,927 Cash and cash equivalents, held for customers 67,369 430,496 Restricted time deposits (1) — 8,341 Due from brokers (2) 20,595 27,552 Accounts receivable, net 4,520 3,272 Deferred tax asset — 7,937 Tax receivable 340 1,065 Office, communication and computer equipment, net 5,815 9,166 Goodwill 223,870 284,645 Other intangible assets, net 27,379 42,229 Other assets (3) (4) 12,404 14,819 Loss recognized on classification as held for sale (27,820 ) — Total assets classified as held for sale on the condensed consolidated statements of financial condition $ 357,894 $ 911,449 ** Liabilities Customer account liabilities $ 67,369 $ 430,496 Accounts payable and accrued expenses (5) 12,901 20,850 Due to brokers (6) 21 330 Securities sold, not yet purchased 3,710 4,239 Deferred tax liability — 1,137 Other liabilities 56 151 Total liabilities classified as held for sale on the condensed consolidated statements of financial condition $ 84,057 $ 457,203 ** ____________________________________ ** Amounts as of December 31, 2014 are classified as current and noncurrent on the condensed consolidated statement of financial condition. (1) The time deposits, initially established in July 2014, secured a letter of guarantee on behalf of FXCMJ. The time deposits remained unwithdrawn and were terminated in connection with the sale of FXCMJ in April 2015. (2) Includes as of September 30, 2015 and December 31, 2014 : a) derivative assets, net of $0.1 million and $0.6 million , respectively; b) Unsettled spot FX of $0.4 million and $4.9 million , respectively; c) Unsettled common stock of $3.0 million and $3.7 million , respectively; and d) Excess cash collateral of $17.1 million and $18.3 million , respectively. (3) Includes the Company's exchange memberships, which represent ownership interests and shares owned in the Chicago Mercantile and Intercontinental exchanges and provide the Company with the right to conduct business on the exchanges. 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. In April 2015, the Company sold all of its shares owned in the Intercontinental exchange and recognized a gain of $0.1 million which is included in Income (loss) from discontinued operations, net of tax in the condensed consolidated statements of operations for the nine months ended September 30, 2015 . There were no exchange membership impairments as of September 30, 2015 or December 31, 2014 . The cost of ownership interests and shares owned was $2.7 million and $3.0 million , respectively, at September 30, 2015 and $2.7 million and $3.7 million , respectively, at December 31, 2014 . (4) Includes as of September 30, 2015 and December 31, 2014 the aggregate carrying values of the Company's equity interests in FastMatch and the V3-related LLC of $6.1 million and $6.9 million , respectively. (5) Includes as of both September 30, 2015 and December 31, 2014 amounts due related to the allocation of income to Lucid non-controlling members for services provided of $8.9 million . (6) Comprised of Unsettled spot FX.

Goodwill (Tables)

Goodwill (Tables)	9 Months Ended
	Sep. 30, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of changes in goodwill	Changes in goodwill for the nine months ended September 30, 2015 are presented in the following table and reflect the Company's single operating segment, with amounts in thousands: Balance as of January 1, 2015* $ 39,242 Impairment of goodwill (9,513 ) Foreign currency translation and other adjustments (1,073 ) Balance as of September 30, 2015 $ 28,656 * Goodwill of $284.6 million was transferred to assets held for sale at December 31, 2014 (see Note 4).

Other Intangible Assets, net (T

Other Intangible Assets, net (Tables)	9 Months Ended
	Sep. 30, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of finite-lived intangible assets	The Company’s intangible assets consisted of the following as of September 30, 2015 and December 31, 2014 , with amounts in thousands: September 30, 2015 December 31, 2014 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Finite-lived intangible assets Customer relationships $ 35,460 $ (19,240 ) $ 16,220 $ 29,460 $ (15,040 ) $ 14,420 Foreign currency translation adjustment (1,534 ) 501 (1,033 ) (500 ) 818 318 Total finite-lived intangible assets $ 33,926 $ (18,739 ) $ 15,187 $ 28,960 $ (14,222 ) $ 14,738 Indefinite-lived intangible assets License 600 — 600 600 — 600 Total Other intangible assets, net $ 34,526 $ (18,739 ) $ 15,787 $ 29,560 $ (14,222 ) $ 15,338
Schedule of indefinite-lived intangible assets	The Company’s intangible assets consisted of the following as of September 30, 2015 and December 31, 2014 , with amounts in thousands: September 30, 2015 December 31, 2014 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Finite-lived intangible assets Customer relationships $ 35,460 $ (19,240 ) $ 16,220 $ 29,460 $ (15,040 ) $ 14,420 Foreign currency translation adjustment (1,534 ) 501 (1,033 ) (500 ) 818 318 Total finite-lived intangible assets $ 33,926 $ (18,739 ) $ 15,187 $ 28,960 $ (14,222 ) $ 14,738 Indefinite-lived intangible assets License 600 — 600 600 — 600 Total Other intangible assets, net $ 34,526 $ (18,739 ) $ 15,787 $ 29,560 $ (14,222 ) $ 15,338
Schedule of estimated future amortization expense for intangible assets	Estimated future amortization expense for intangible assets outstanding as of September 30, 2015 is as follows, with amounts in thousands: Year Ending December 31, Remainder of 2015 $ 1,975 2016 7,295 2017 4,055 2018 1,492 2019 370 Thereafter — $ 15,187

Earnings per Share (Tables)

Earnings per Share (Tables)	9 Months Ended
	Sep. 30, 2015
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 September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Basic and diluted net income (loss) per share of Class A common stock: Numerator Income (loss) from continuing operations attributable to FXCM Inc. $ 64,302 $ 1,956 $ (427,909 ) $ (1,431 ) Income (loss) from discontinued operations attributable to FXCM Inc. 9,347 436 (21,070 ) 2,822 Net income (loss) available to holders of Class A common stock 73,649 2,392 (448,979 ) 1,391 Earnings allocated to participating securities — — — — Income (loss) income available to common stockholders $ 73,649 $ 2,392 $ (448,979 ) $ 1,391 Denominator Weighted average shares of Class A common stock (1) 5,313 4,296 4,968 4,011 Add dilutive effect of the following: Weighted average of Lucid's second anniversary shares issued on June 18, 2014 — — — — Stock options and RSUs (1),(2) — 86 — — Convertible note hedges — — — — Warrants — — — — Assumed conversion of Holdings Units for Class A common stock — — — — Dilutive weighted average shares of Class A common stock (1) 5,313 4,382 4,968 4,011 Net income (loss) per share of Class A common stock (1) : Basic: Continuing operations $ 12.10 $ 0.46 $ (86.13 ) $ (0.36 ) Discontinued operations 1.76 0.10 (4.24 ) 0.70 Basic net income (loss) per share of Class A common stock $ 13.86 $ 0.56 $ (90.37 ) $ 0.34 Diluted: Continuing operations $ 12.10 $ 0.45 $ (86.13 ) $ (0.36 ) Discontinued operations 1.76 0.10 (4.24 ) 0.70 Diluted net income (loss) per share of Class A common stock $ 13.86 $ 0.55 $ (90.37 ) $ 0.34 ____________________________________ (1) Adjusted to reflect the impact of the one-for-ten reverse stock split that became effective on October 1, 2015, as discussed in Note 1. (2) No dilutive effect for the three months ended September 30, 2015 therefore zero incremental shares included for the period.

Related Party Transactions (Tab

Related Party Transactions (Tables)	9 Months Ended
	Sep. 30, 2015
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 September 30, 2015 December 31, 2014 Receivables Advances to Holdings non-controlling members $ 49 $ 196 Accounts receivable — Lucid non-controlling members 15 799 Accounts receivable — equity method investment — 1,468 Advances to employees 212 563 Notes receivable and interest — Lucid non-controlling members 8,131 8,013 Total receivables from related parties $ 8,407 $ 11,039 Payables Guarantee agreement ("Monetary Guaranty") $ — $ 7,078 Employees 806 2,009 Due to Lucid non-controlling members in connection with the allocation of income to Lucid non-controlling members for services provided 8,938 8,876 Accounts payable — equity method investment 448 — Tax receivable agreement — 150,576 Total payables to related parties $ 10,192 $ 168,539

Net Capital Requirements (Table

Net Capital Requirements (Tables)	9 Months Ended
	Sep. 30, 2015
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 September 30, 2015 and December 31, 2014 , with amounts in millions: As of September 30, 2015 US UK LTD Australia ODL FSL Lucid LLP Capital $ 48.3 $ 78.4 $ 3.2 $ 9.1 $ 5.5 $ 12.2 Minimum capital requirement 28.9 30.0 0.7 1.3 0.9 2.0 Excess capital $ 19.4 $ 48.4 $ 2.5 $ 7.8 $ 4.6 $ 10.2 As of December 31, 2014 US UK LTD HK Australia ODL FSL FXCMJ Lucid LLP Faros Capital $ 69.5 $ 101.6 $ 31.2 $ 3.0 $ 25.5 $ 40.2 $ 36.3 $ 22.8 $ 0.4 Minimum capital requirement 30.0 29.2 14.8 0.8 3.0 5.2 6.3 3.8 — Excess capital $ 39.5 $ 72.4 $ 16.4 $ 2.2 $ 22.5 $ 35.0 $ 30.0 $ 19.0 $ 0.4

Leucadia Transaction (Tables)

Leucadia Transaction (Tables)	9 Months Ended
	Sep. 30, 2015
Extraordinary and Unusual Items [Abstract]
Schedule of allocation of net proceeds from letter agreement	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 September 30, 2015 , was as follows, with amounts in thousands: As of September 30, 2015 Debt principal $ 202,861 Original issue discount (46,171 ) Discount — issuance fee (6,605 ) Deferred financing fee (4,755 ) Debt — net carrying value $ 145,330
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 nine months ended September 30, 2015 , consists of the following, with amounts in thousands: Three Months Ended September 30, 2015 Nine Months Ended September 30, 2015 Contractual interest $ 7,301 $ 20,202 Deferred interest 734 5,586 Amortization of original issue discount 14,686 55,373 Amortization of issuance fee discount 1,969 7,287 Amortization of deferred financing fee 1,417 5,245 Amortization of debt acquisitions costs 176 651 Total interest expense — Credit Agreement $ 26,283 $ 94,344

Debt (Tables)

Debt (Tables)	9 Months Ended
	Sep. 30, 2015
Debt Disclosure [Abstract]
Balance of liability and equity components of convertible debt	The balances of the liability and equity components as of September 30, 2015 and December 31, 2014 , were as follows, with amounts in thousands: As of September 30, 2015 December 31, 2014 Liability component — principal $ 172,500 $ 172,500 Deferred bond discount (16,742 ) (20,922 ) Liability component — net carrying value $ 155,758 $ 151,578 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 September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Stated coupon rate $ 970 $ 970 $ 2,911 $ 2,911 Amortization of deferred bond discount 1,419 1,335 4,180 3,932 Amortization of debt issuance cost 302 302 907 907 Total interest expense — Convertible Notes $ 2,691 $ 2,607 $ 7,998 $ 7,750

Derivative Financial Instrume39

Derivative Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of derivative assets and liabilities net of counterparty and collateral offsets	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 September 30, 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 (1) $ 4,429 $ 76,440 $ — $ — CFD contracts Due from/Due to brokers (2) 134 181,480 9 35,352 Futures contracts Due from/Due to brokers and Current assets/liabilities held for sale (1), (2) 2,457 402,962 8,661 1,109,179 Total derivatives, gross $ 7,020 $ 660,882 $ 8,670 $ 1,144,531 Netting agreements and cash collateral netting (6,654 ) (8,670 ) Total derivatives, net $ 366 $ — ____________________________________ (1) As of September 30, 2015 , the aggregate fair values of derivative assets and liabilities, gross related to discontinued operations is $6.7 million and $8.6 million , respectively. These amounts are offset by netting agreements and cash collateral netting of $6.6 million and $8.6 million , respectively. (2) As of September 30, 2015 , the aggregate fair values of derivative assets and liabilities, gross related to continuing operations is $0.3 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. As of December 31, 2014 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) $ 10,724 $ 95,498 $ 11,422 $ 81,053 Futures contracts Due from/Due to brokers and Current assets/liabilities held for sale (3) (4) 332,346 3,617,128 352,703 3,627,562 OTC options Current liabilities held for sale (3) — — 1,086 1,086 Total derivatives, gross $ 343,070 $ 3,712,626 $ 365,211 $ 3,709,701 Netting agreements and cash collateral netting (342,467 ) (353,543 ) Total derivatives, net $ 603 $ 11,668 ____________________________________ (3) As of December 31, 2014 , the aggregate fair values of derivative assets and liabilities, gross related to discontinued operations is $342.7 million and $353.1 million , respectively. These amounts are offset by netting agreements and cash collateral netting of $342.1 million and $353.1 million , respectively. (4) As of December 31, 2014 , the aggregate fair value of derivative assets and liabilities, gross related to continuing operations is $0.4 million and $12.1 million , respectively. These amounts are offset by netting agreements and cash collateral netting of $0.4 million and $0.4 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 nine months ended September 30, 2015 and 2014 , with amounts in thousands: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 Exchange traded options (5) $ 6,049 $ (5,916 ) $ 5,320 $ 14,002 CFD contracts (6) 3,216 — (2,131 ) — Futures contracts (7) 5,053 (21,181 ) 43,115 (7,428 ) OTC options (5) — (777 ) 1,086 (394 ) Total $ 14,318 $ (27,874 ) $ 47,390 $ 6,180 ____________________________________ (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. (7) The portion included in Income (loss) from continuing operations in the condensed consolidated statements of operations is $7.5 million and $25.8 million for the three and nine months ended September 30, 2015 , respectively, and $(33.0) million and $(12.2) million for the three and nine months ended September 30, 2014 , respectively.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2015
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 September 30, 2015 Level 1 Level 2 Level 3 Counterparty and Cash Collateral Netting Total Financial Assets: Derivative assets: Exchange traded options $ 4,429 $ — $ — $ — $ 4,429 CFD contracts — 134 — — 134 Futures contracts 2,457 — — — 2,457 Netting — — — (6,654 ) (6,654 ) Total derivative assets (1) 6,886 134 — (6,654 ) 366 Total assets $ 6,886 $ 134 $ — $ (6,654 ) $ 366 Financial Liabilities: Customer account liabilities (2) $ — $ 780,573 $ — $ — $ 780,573 Derivative liabilities: CFD contracts — 9 — — 9 Futures contracts 8,661 — — — 8,661 Netting — — — (8,670 ) (8,670 ) Total derivative liabilities (1) 8,661 9 — (8,670 ) — Securities sold, not yet purchased (3) 3,710 — — — 3,710 Letter Agreement — — 348,531 — 348,531 Total liabilities $ 12,371 $ 780,582 $ 348,531 $ (8,670 ) $ 1,132,814 Fair Value Measurements on a Recurring Basis As of December 31, 2014 Level 1 Level 2 Level 3 Counterparty and Cash Collateral Netting Total Financial Assets: Trading securities (3) $ 26 $ — $ — $ — $ 26 Derivative assets: Exchange traded options 10,724 — — — 10,724 Futures contracts 332,346 — — — 332,346 Netting — — — (342,467 ) (342,467 ) Total derivative assets (1) 343,070 — — (342,467 ) 603 Total assets $ 343,096 $ — $ — $ (342,467 ) $ 629 Financial Liabilities: Customer account liabilities (2) $ — $ 1,331,723 $ — $ — $ 1,331,723 Derivative liabilities: Exchange traded options 11,422 — — — 11,422 Futures contracts 352,703 — — — 352,703 OTC options — 1,086 — — 1,086 Netting — — — (353,543 ) (353,543 ) Total derivative liabilities (1) 364,125 1,086 — (353,543 ) 11,668 Securities sold, not yet purchased (3) 4,239 — — — 4,239 Total liabilities $ 368,364 $ 1,332,809 $ — $ (353,543 ) $ 1,347,630 ____________________________________ (1) Relates to continuing and discontinued operations. See Note 15 for details of the classification of amounts on the condensed consolidated statements of financial position. (2) Relates to continuing and discontinued operations. See Note 4 for amount classified as liabilities held for sale on the condensed consolidated statements of financial position. (3) Relates to discontinued operations. Amounts classified as held for sale on the condensed consolidated statements of financial position (see Note 4).
Summary of significant Level 3 fair value inputs	The significant Level 3 inputs, summarized in the following table, are considered more relevant in the analysis and are given a higher weighting in the overall fair value determination (see Note 12). As of September 30, 2015 Valuation Technique Significant Unobservable Input(s) Input Option-Pricing Method Term (years) 2.7 Volatility 58.9 % Risk-free rate 0.8 % Dividend yield — % Reliance placed on public indication of value 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 September 30, 2015 Fair Value Measurements using: Carrying Value Fair Value Level 1 Level 2 Level 3 Financial Assets: Due from brokers — unsettled spot FX (4) $ 24,219 $ 24,219 $ — $ 24,219 $ — Due from brokers — unsettled common stock (5) 3,054 3,054 — 3,054 — Due from brokers — excess cash collateral (5) 16,963 16,963 — 16,963 — Equity method investments (4) 8,887 18,359 — — 18,359 Notes receivable 7,881 7,881 — — 7,881 Exchange memberships (5) 5,770 6,325 — 6,325 — Total assets $ 66,774 $ 76,801 $ — $ 50,561 $ 26,240 Financial Liabilities: Due to brokers — unsettled spot FX (4) $ 81 $ 81 $ — $ 81 $ — Senior convertible notes 155,758 129,377 — 129,377 — Credit Agreement 145,330 202,861 — — 202,861 Total liabilities $ 301,169 $ 332,319 $ — $ 129,458 $ 202,861 As of December 31, 2014 Fair Value Measurements using: Carrying Value Fair Value Level 1 Level 2 Level 3 Financial Assets: Restricted time deposits (5) $ 8,341 $ 8,341 $ — $ 8,341 $ — Due from brokers — unsettled spot FX (4) 14,635 14,635 — 14,635 — Due from brokers — unsettled common stock (5) 3,730 3,730 — 3,730 — Due from brokers — excess cash collateral (5) 18,330 18,330 — 18,330 — Equity method investments (4) 10,007 17,199 — — 17,199 Notes receivable 9,381 9,381 — — 9,381 Exchange memberships (5) 6,429 7,802 — 7,802 — Total assets $ 70,853 $ 79,418 $ — $ 52,838 $ 26,580 Financial Liabilities: Due to brokers — unsettled spot FX (4) 4,645 4,645 — 4,645 — Revolving credit agreement 25,000 25,000 — 25,000 — Senior convertible notes 151,578 147,266 — 147,266 — Total liabilities $ 181,223 $ 176,911 $ — $ 176,911 $ — ____________________________________ (4) Relates to continuing and discontinued operations. See Note 4 for amounts classified as held for sale on the condensed consolidated statements of financial condition. (5) Relates 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 table reconciles the opening and ending balance of the recurring fair value measurement categorized as Level 3, which is included in the condensed consolidated statements of financial condition as of September 30, 2015 , and identifies the total losses the Company recognized during the nine months ended September 30, 2015 , with amounts in thousands: As of September 30, 2015 Beginning Balance Additions Net Unrealized Loss Ending balance Letter Agreement $ — $ 94,436 $ 254,095 $ 348,531 Total Level 3 liabilities $ — $ 94,436 $ 254,095 $ 348,531

Description of Business and B41

Description of Business and Basis of Presentation - Additional Information (Detail)	Sep. 30, 2015
Lucid Markets Trading Limited
Basis of Presentation [Line Items]
Noncontrolling equity interest	49.90%

Non-Controlling Interests - Cha

Non-Controlling Interests - Change in Interest Holdings of Corporation and Non-Controlling Interest (Detail)	9 Months Ended
	Sep. 30, 2015shares
Controlling Units
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance (in shares)	4,788,996.4
Beginning balance (percent)	58.10%
Holding units acquired by FXCM Inc. related to exchanges of Holdings units for shares of Class A common stock (in shares)	583,670
Holdings units acquired by FXCM Inc. related to exchanges of Holdings units for shares of Class A common stock (percent)	7.10%
Ending balance (in shares)	5,372,666
Ending balance (percent)	65.20%
Non- Controlling Units
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance (in shares)	3,445,767.4
Beginning balance (percent)	41.90%
Holding units acquired by FXCM Inc. related to exchanges of Holdings units for shares of Class A common stock (in shares)	(583,670)
Holdings units acquired by FXCM Inc. related to exchanges of Holdings units for shares of Class A common stock (percent)	(7.10%)
Ending balance (in shares)	2,862,097
Ending balance (percent)	34.80%
Total Units
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance (in shares)	8,234,763
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)	8,234,763
Ending balance (percent)	100.00%

Discontinued Operations - Incom

Discontinued Operations - Income Statement (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Revenues
Trading revenue	$ 13,386	$ 23,547	$ 60,154	$ 71,282
Interest income	29	118	247	400
Brokerage interest expense	(29)	(25)	(100)	(89)
Net interest revenue	0	93	147	311
Other income	1,430	1,122	4,802	8,183
Total net revenues	14,816	24,762	65,103	79,776
Operating Expenses
Compensation and benefits	731	4,255	11,532	13,603
Allocation of net income to Lucid members for services provided	2,249	1,483	6,916	6,771
Total compensation and benefits	2,980	5,738	18,448	20,374
Referring broker fees	0	263	208	963
Advertising and marketing	15	1,004	736	2,426
Communication and technology	2,061	2,983	6,528	9,238
Trading costs, prime brokerage and clearing fees	4,178	5,627	14,716	18,311
General and administrative	978	2,347	4,215	7,220
Bad debt expense	0	0	8,408	0
Depreciation and amortization	0	7,124	12,359	20,287
Goodwill impairment loss	0	0	54,865	0
Total operating expenses	10,212	25,086	120,483	78,819
Operating income (loss)	4,604	(324)	(55,380)	957
Other Expense
Loss on equity method investments, net	320	239	821	606
Income (loss) from discontinued operations before income taxes	4,284	(563)	(56,201)	351
Gain on completed dispositions	12,449	0	14,427	0
Gain (loss) on classification as held for sale before income taxes	(979)	0	27,820	0
Total income (loss) from discontinued operations before income taxes	17,712	(563)	(69,594)	351
Income tax (benefit) provision	(306)	(206)	5,321	282
Income (loss) from discontinued operations, net of tax	18,018	(357)	(74,915)	69
Income (loss) before income taxes, attributable to parent	$ 9,100	$ 500	$ (19,800)	$ 3,600

Discontinues Operations - Balan

Discontinues Operations - Balance Sheet (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Assets
Cash and cash equivalents	$ 23,422	$ 81,927
Cash and cash equivalents, held for customers	67,369	430,496
Restricted time deposits	0	8,341
Due from brokers	20,595	27,552
Accounts receivable, net	4,520	3,272
Deferred tax asset	0	7,937
Tax receivable	340	1,065
Office, communication and computer equipment, net	5,815	9,166
Goodwill	223,870	284,645
Other intangible assets, net	27,379	42,229
Other assets	12,404	14,819
Loss recognized on classification as held for sale	(27,820)	0
Total assets classified as held for sale on the condensed consolidated statements of financial condition	357,894	911,449
Liabilities
Customer account liabilities	67,369	430,496
Accounts payable and accrued expenses	12,901	20,850
Due to brokers	21	330
Securities sold, not yet purchased	3,710	4,239
Deferred tax liability	0	1,137
Other liabilities	56	151
Total liabilities classified as held for sale on the condensed consolidated statements of financial condition	84,057	457,203
Due from correspondent brokers, derivative assets, net	100	600
Due from correspondent brokers, unsettled spot foreign exchange	400	4,900
Due from correspondent brokers, unsettled common stock	3,000	3,700
Due from correspondent brokers, excess cash collateral	17,100	18,300
Other assets, exchange memberships, cost of ownership interests	2,700	2,700
Other assets, exchange memberships, cost of shares owned	3,000	3,700
Other assets, equity method investments	6,100	6,900
Accounts payable and accrued liabilities, due to related party	8,900	$ 8,900
International Exchanges
Liabilities
Gain on disposal of discontinued operations, net of tax	$ 100

Discontinued Operations Discont

Discontinued Operations Discontinued Operations - Additional Information (Details) - USD ($)	Sep. 11, 2015	Apr. 01, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Realization of cumulative translation adjustment			$ 0	$ 0	$ 23,407,000	$ 0
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 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			800,000		1,600,000
Faros
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration received for disposal group			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 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			$ 100,000

Notes Receivable - Additional I

Notes Receivable - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended		9 Months Ended
	May. 31, 2014	Jan. 31, 2014	Sep. 30, 2015	Sep. 30, 2014
Lucid Markets Trading Limited
Accounts, Notes, Loans and Financing Receivable [Line Items]
Related party notes receivable		$ 7.9
AxiCorp
Accounts, Notes, Loans and Financing Receivable [Line Items]
Related party notes receivable	$ 1.5
Notes Receivable | Lucid Markets Trading Limited
Accounts, Notes, Loans and Financing Receivable [Line Items]
Related party notes receivable interest rate		2.00%
Related party interest income			$ 0.1	$ 0.1
Notes Receivable | AxiCorp
Accounts, Notes, Loans and Financing Receivable [Line Items]
Related party notes receivable interest rate	15.00%

Equity Method Investment - Addi

Equity Method Investment - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014	Jan. 31, 2014	Dec. 31, 2012
Schedule of Equity Method Investments [Line Items]
Loss on equity method investments, net	$ 111	$ 137	$ 299	$ 304
FX Trading Software Developer
Schedule of Equity Method Investments [Line Items]
Percentage of equity interest	22.10%		22.10%
Carrying value of equity method investments	$ 2,800		$ 2,800		$ 3,100
FX Trading Software Developer | Loss on Equity Method Investments, Net
Schedule of Equity Method Investments [Line Items]
Loss on equity method investments, net		100	$ 300	300
FASTMATCH
Schedule of Equity Method Investments [Line Items]
Percentage of equity interest							35.40%
V3
Schedule of Equity Method Investments [Line Items]
Percentage of equity interest	66.30%		66.30%			66.30%
Firm that Provides a Financial Intelligence Platform | V3
Schedule of Equity Method Investments [Line Items]
Percentage of equity interest						17.26%
FASTMATCH and V3 | Assets Held-for-sale
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	$ 6,100		$ 6,100		$ 6,900
FASTMATCH and V3 | Income (Loss) from Discontinued Operations, Net of Tax [Member]
Schedule of Equity Method Investments [Line Items]
Loss on equity method investments, net	$ 300	$ 200	$ 800	$ 600

Goodwill (Details)

Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Beginning balance			$ 39,242
Impairment of goodwill	$ 0	$ 0	(9,513)	$ 0
Foreign currency translation and other adjustments			(1,073)
Ending balance	28,656		28,656
Goodwill transferred to assets held for sale	$ 223,870		$ 223,870		$ 284,645

Other Intangible Assets, net -

Other Intangible Assets, net - Schedule of Acquired Finite and Indefinite Lived Intangible Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Finite-lived intangible assets
Gross Carrying Amount	$ 33,926	$ 28,960
Accumulated Amortization	(18,739)	(14,222)
Net Carrying Amount	15,187	14,738
Indefinite-lived intangible assets
Intangible assets, gross (excluding goodwill)	34,526	29,560
Total intangible assets, net (excluding goodwill)	15,787	15,338
License
Indefinite-lived intangible assets
Indefinite-lived intangible assets	600	600
Customer relationships
Finite-lived intangible assets
Gross Carrying Amount	35,460	29,460
Accumulated Amortization	(19,240)	(15,040)
Net Carrying Amount	16,220	14,420
Foreign currency translation adjustment
Finite-lived intangible assets
Gross Carrying Amount	(1,534)	(500)
Accumulated Amortization	501	818
Net Carrying Amount	$ (1,033)	$ 318

Other Intangible Assets, net 50

Other Intangible Assets, net - Estimated Future Amortization Expense for Acquired Intangible Assets Outstanding (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Remainder of 2015	$ 1,975
2,016	7,295
2,017	4,055
2,018	1,492
2,019	370
Thereafter	0
Net Carrying Amount	$ 15,187	$ 14,738

Other Intangible Assets, net 51

Other Intangible Assets, net - Additional Information (Details) - USD ($)	1 Months Ended	3 Months Ended			9 Months Ended
	Jun. 30, 2015	Sep. 30, 2015	Mar. 31, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Finite-Lived Intangible Assets [Line Items]
Impairment losses			$ 5,400,000
Amortization expense		$ 2,000,000		$ 1,200,000	$ 5,000,000	$ 3,100,000
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

Earnings Per Share - Reconcilia

Earnings Per Share - Reconciliation of Numerator and Denominator Used in Basic and Diluted EPS Calculations (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended				9 Months Ended
		Sep. 30, 2015	Mar. 31, 2015	Sep. 30, 2014	Mar. 31, 2014	Sep. 30, 2015	Sep. 30, 2014
Numerator
Income (loss) from continuing operations attributable to FXCM Inc.		$ 64,302		$ 1,956		$ (427,909)	$ (1,431)
Income (loss) from discontinued operations attributable to FXCM Inc.		9,347		436		(21,070)	2,822
Net income (loss) available to holders of Class A common stock		$ 73,649		$ 2,392		$ (448,979)	$ 1,391
Add dilutive effect of the following:
Dilutive weighted average shares of Class A common stock	[1]	5,313		4,382		4,968	4,011
Diluted:
Continuing operations (in dollars per share)		$ 12.10		$ 0.45			$ (0.36)
Discontinued operations (in dollars per share)		1.76		0.10			0.70
Diluted net income (loss) attributable to FXCM Inc. (in dollars per share)		$ 13.86		$ 0.55			$ 0.34
Common Class A
Numerator
Income (loss) from continuing operations attributable to FXCM Inc.		$ 64,302		$ 1,956		$ (427,909)	$ (1,431)
Income (loss) from discontinued operations attributable to FXCM Inc.		9,347		436		(21,070)	2,822
Net income (loss) available to holders of Class A common stock		73,649		2,392		(448,979)	1,391
Earnings allocated to participating securities		0		0		0	0
Income (loss) income available to common stockholders		$ 73,649		$ 2,392		$ (448,979)	$ 1,391
Denominator
Weighted average shares of Class A common stock		5,313		4,296		4,968	4,011
Add dilutive effect of the following:
Stock options and RSUs		0		86		0	0
Convertible note hedges		0		0		0	0
Warrants		0		0		0	0
Assumed conversion of Holdings Units for Class A common stock		0		0		0	0
Dilutive weighted average shares of Class A common stock		5,313		4,382		4,968	4,011
Basic:
Continuing operations (in dollars per share)		$ 12.10		$ 0.46		$ (86.13)	$ (0.36)
Discontinued operations (in dollars per share)		1.76		0.10		(4.24)	0.70
Basic net income (loss) attributable to FXCM Inc. (in dollars per share)		13.86		0.56		(90.37)	0.34
Diluted:
Continuing operations (in dollars per share)		12.10		0.45		(86.13)	(0.36)
Discontinued operations (in dollars per share)		1.76		0.10		(4.24)	0.70
Diluted net income (loss) attributable to FXCM Inc. (in dollars per share)		$ 13.86		$ 0.55		$ (90.37)	$ 0.34
Common Class A | Lucid Markets Trading Limited | Second Anniversary, Shares Issued
Add dilutive effect of the following:
Weighted average of Lucid's second anniversary shares issued on June 18, 2014			0		0	0	0
[1]	Adjusted to reflect the impact of the one-for-ten reverse stock split that became effective on October 1, 2015, as discussed in Note 1.

Earnings Per Share - Additional

Earnings Per Share - Additional Information (Detail)	Oct. 01, 2015	Jun. 30, 2015shares	Apr. 30, 2015$ / sharesshares	Jun. 30, 2014shares	Jun. 30, 2013USD ($)$ / sharesshares	Jun. 30, 2012shares	Sep. 30, 2015shares	Sep. 30, 2014shares	Sep. 30, 2015shares	Sep. 30, 2014shares	Apr. 15, 2015$ / sharesshares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Duration of Option Agreement			2 years
Number of shares available under Option Agreement (in shares)			56,934
Exercise price per share under Option Agreement (in dollars per share) | $ / shares			$ 22.50								$ 22.50
Stock option granted excluded from computation of earnings per share							7,668,232	103,199	766,823.2	764,047.3
Senior Notes | 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 | $ / shares					$ 187.62
Common Class A
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of shares available under Option Agreement (in shares)											56,934
Conversion ratio									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)								0	600,000	100,000
Common Class A | Senior Notes | 2.25% Senior Convertible Notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Conversion ratio					0.00532992
Common Class A | Common Stock | Lucid Markets Trading Limited
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Business acquisitions, shares issued		300,000		300,000	120,000	720,000
Subsequent Event | Common Class A
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Reverse stock split (in shares)	0.1

Related Party Transactions - Am

Related Party Transactions - Amounts Receivable From, And Payable To, Related Parties (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Receivables
Advances to Holdings non-controlling members	$ 49	$ 196
Advances to employees	212	563
Total receivables from related parties	8,407	11,039
Payables
Employees	806	2,009
Tax receivable agreement	0	150,576
Total payables to related parties	10,192	168,539
Lucid Markets Trading Limited
Receivables
Accounts receivable, related parties	15	799
Notes receivable and interest — Lucid non-controlling members	8,131	8,013
FASTMATCH
Receivables
Accounts receivable, related parties	0	1,468
Payables
Accounts payable — equity method investment	448	0
Monetary Credit Group LLC
Payables
Guarantee agreement (Monetary Guaranty)	0	7,078
Holding Non Controlling Units
Payables
Due to Lucid non-controlling members in connection with the allocation of income to Lucid non-controlling members for services provided	$ 8,938	$ 8,876

Related Partly Transactions - A

Related Partly Transactions - Additional Information (Detail) shares in Millions	Oct. 01, 2015	Jan. 31, 2014USD ($)	Sep. 30, 2015USD ($)	Sep. 30, 2014USD ($)shares	Sep. 30, 2015USD ($)shares	Sep. 30, 2014USD ($)shares	Dec. 31, 2014USD ($)	Dec. 31, 2012
Related Party Transaction [Line Items]
Referring broker fees			$ 13,032,000	$ 20,735,000	$ 43,702,000	$ 55,652,000
Tax receivable agreement before valuation			146,300,000		146,300,000
Tax receivable agreement			0		0		$ 150,576,000
Payments for tax receivable agreement					$ 5,352,000	$ 3,707,000
Common Stock - Class A
Related Party Transaction [Line Items]
Conversion ratio					1
Common Stock - Class A | Subsequent Event
Related Party Transaction [Line Items]
Reverse stock split (in shares)	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				0	0.6	0.1
Exchange of Holding Units into Class A common stock | shares						0.1
Referring broker fees | Global Finance and Master Capital
Related Party Transaction [Line Items]
Referring broker fees			0	$ 300,000	$ 200,000	$ 900,000
FASTMATCH
Related Party Transaction [Line Items]
Percentage of equity interest								35.40%
Lucid Markets Trading Limited
Related Party Transaction [Line Items]
Accounts receivable, related parties			15,000		15,000		799,000
Related party notes receivable		$ 7,900,000
Lucid Markets Trading Limited | Notes Receivable
Related Party Transaction [Line Items]
Related party notes receivable interest rate		2.00%
Related party interest income					100,000	100,000
FASTMATCH
Related Party Transaction [Line Items]
Accounts receivable, related parties			0		0		1,468,000
Accounts payable, related parties			448,000		448,000		$ 0
Related party transaction, disposal of property, plant, and equipment					500,000
FASTMATCH | Other income
Related Party Transaction [Line Items]
Revenue from related parties			200,000
FASTMATCH | Trading revenues
Related Party Transaction [Line Items]
Brokerage commissions revenue			0	4,100,000	6,300,000	8,800,000
FASTMATCH | Communication and technology
Related Party Transaction [Line Items]
Exchange fees			0	3,000,000	4,300,000	6,200,000
Shareholder great than a 5% ownership | Global Finance and Master Capital
Related Party Transaction [Line Items]
Percentage of ownership interests							90.00%
Monetary Credit Group LLC
Related Party Transaction [Line Items]
Aggregate amount of margin extended under the monetary guaranty							$ 13,200,000
Guarantee agreement (Monetary Guaranty)			0		0		7,078,000
Guarantor obligations, fees collected			0	$ 300,000		$ 500,000
Holding Non Controlling Units
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			$ 8,938,000		$ 8,938,000		$ 8,876,000

Net Capital Requirements - Mini

Net Capital Requirements - Minimum Capital Requirement And Excess Capital (Detail) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
US
Capital Requirements on Foreign Financial Institutions [Line Items]
Capital	$ 48.3	$ 69.5
Minimum capital requirement	28.9	30
Excess capital	19.4	39.5
UK LTD
Capital Requirements on Foreign Financial Institutions [Line Items]
Capital	78.4	101.6
Minimum capital requirement	30	29.2
Excess capital	48.4	72.4
HK
Capital Requirements on Foreign Financial Institutions [Line Items]
Capital		31.2
Minimum capital requirement		14.8
Excess capital		16.4
Australia
Capital Requirements on Foreign Financial Institutions [Line Items]
Capital	3.2	3
Minimum capital requirement	0.7	0.8
Excess capital	2.5	2.2
ODL
Capital Requirements on Foreign Financial Institutions [Line Items]
Capital	9.1	25.5
Minimum capital requirement	1.3	3
Excess capital	7.8	22.5
FSL
Capital Requirements on Foreign Financial Institutions [Line Items]
Capital	5.5	40.2
Minimum capital requirement	0.9	5.2
Excess capital	4.6	35
FXCMJ
Capital Requirements on Foreign Financial Institutions [Line Items]
Capital		36.3
Minimum capital requirement		6.3
Excess capital		30
Lucid LLP
Capital Requirements on Foreign Financial Institutions [Line Items]
Capital	12.2	22.8
Minimum capital requirement	2	3.8
Excess capital	$ 10.2	19
Faros
Capital Requirements on Foreign Financial Institutions [Line Items]
Capital		0.4
Minimum capital requirement		0
Excess capital		$ 0.4

Leucadia Transaction - Allocati

Leucadia Transaction - Allocation of Net Proceeds (Details) - USD ($)	Apr. 16, 2015	Jan. 24, 2015
Amounts due under Leucadia term loan, including fees | Leucadia
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions		100.00%
Amounts due under Leucadia term loan, including fees | FXCM Holdings
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions		0.00%
Next $350 million
Unusual or Infrequent Item [Line Items]
Letter agreement, stipulated proceeds amount		$ 350,000,000
Next $350 million | Leucadia
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions		50.00%
Next $350 million | FXCM Holdings
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions		50.00%
Next $500 million
Unusual or Infrequent Item [Line Items]
Letter agreement, stipulated proceeds amount	$ 500,000,000
Next $500 million | Leucadia
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions		90.00%
Next $500 million | FXCM Holdings
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions		10.00%
All aggregate amounts thereafter | Leucadia
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions		60.00%
All aggregate amounts thereafter | FXCM Holdings
Unusual or Infrequent Item [Line Items]
Letter agreement, allocation percentage of proceeds from stipulated transactions		40.00%
Minimum | Next $500 million
Unusual or Infrequent Item [Line Items]
Letter agreement, stipulated proceeds amount		$ 500,000,000
Maximum | Next $500 million
Unusual or Infrequent Item [Line Items]
Letter agreement, stipulated proceeds amount		$ 680,000,000

Leucadia Transaction - Credit A

Leucadia Transaction - Credit Agreement Carrying Value (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Debt — net carrying value	$ 145,330	$ 0
Credit Agreement
Debt Instrument [Line Items]
Debt principal	202,861
Original issue discount	(46,171)
Discount — issuance fee	(6,605)
Deferred financing fee	(4,755)
Debt — net carrying value	$ 145,330

Leucadia Transaction - Credit59

Leucadia Transaction - Credit Agreement Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2015	Sep. 30, 2014
Debt Instrument [Line Items]
Amortization of original issue discount — Credit Agreement		$ 55,373	$ 0
Amortization of deferred financing cost		2,351	$ 1,381
Credit Agreement
Debt Instrument [Line Items]
Contractual interest	$ 7,301	20,202
Deferred interest	734	5,586
Amortization of original issue discount — Credit Agreement	14,686	55,373
Amortization of deferred financing cost	1,969	7,287
Amortization of deferred financing fee	1,417	5,245
Amortization of debt acquisitions costs	176	651
Total interest expense	$ 26,283	$ 94,344

Leucadia Transaction - Addition

Leucadia Transaction - Additional Information (Details)	Oct. 01, 2015	Apr. 16, 2015USD ($)	Jan. 28, 2015	Jan. 24, 2015USD ($)	Jan. 15, 2015USD ($)	Sep. 30, 2015USD ($)$ / shares	Jun. 30, 2015USD ($)	Sep. 30, 2014USD ($)	Sep. 30, 2015USD ($)$ / shares	Sep. 30, 2014USD ($)	Mar. 31, 2015$ / shares	Dec. 31, 2014USD ($)
Unusual or Infrequent Item [Line Items]
Bad debt expense						$ 0		$ 0	$ 257,303,000	$ 0
Long-term debt						145,330,000			145,330,000			$ 0
Deferred finance costs, gross				$ 21,000,000
Effective interest rate				39.80%
Loss on derivative, net						(14,318,000)		27,874,000	(47,390,000)	(6,180,000)
Derivative liability						348,531,000			348,531,000			$ 0
Gain (loss) on derivative liability						$ 137,566,000		$ 0	(254,730,000)	0
Amortization of deferred financing cost									2,351,000	$ 1,381,000
Additional deferred finance costs, gross				$ 1,800,000
Common Stock - Class A | Subsequent Event
Unusual or Infrequent Item [Line Items]
Reverse stock split (in shares)	0.1
Letter Agreement
Unusual or Infrequent Item [Line Items]
Deferred finance costs, gross				7,100,000
Fair value of derivative liability				124,800,000
Loss on derivative, net									$ 30,400,000
Valuation based on common stock closing price per share (in dollars per share) | $ / shares						$ 8.70			$ 8.70
Derivative liability, model derived common stock price per share (in dollars per share) | $ / shares											$ 11.10
Effect of $0.25 increase in common stock price, increase in fair value						$ 55,200,000			$ 55,200,000
Effect of $0.25 decrease in common stock price, decrease in fair value						61,100,000			61,100,000
Effect of 10% increase in expected volatility rate, decrease in fair value						35,300,000			35,300,000
Effect of 10% decrease in expected volatility rate, increase in fair value						40,900,000			40,900,000
Additional deferred finance costs, gross				1,200,000
Letter Agreement | Loss on Derivative Liability - Letter Agreement
Unusual or Infrequent Item [Line Items]
Gain (loss) on derivative liability						(137,600,000)			254,100,000
Letter Agreement | Derivative Liability - Letter Agreement
Unusual or Infrequent Item [Line Items]
Derivative liability						348,500,000			348,500,000
Credit Agreement
Unusual or Infrequent Item [Line Items]
Long-term debt						145,330,000			145,330,000
Deferred finance costs, gross				13,900,000
Amortization of deferred financing cost						1,969,000			7,287,000
Additional deferred finance costs, gross				$ 600,000
Amortization of additional financing costs						176,000			651,000
Additional deferred finance costs, net						600,000			600,000
Amortization of deferred financing fee						1,417,000			5,245,000
Credit Agreement | Interest on Borrowings
Unusual or Infrequent Item [Line Items]
Amortization of deferred financing cost						2,000,000			7,300,000
Amortization of additional financing costs						200,000			600,000
Amortization of deferred financing fee						1,400,000			5,200,000
FXCM Holdings
Unusual or Infrequent Item [Line Items]
Percentage of ownership interests				90.00%
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%
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
Leucadia | Loans Payable | Holdings and Newco
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							107,100,000
Long-term debt		$ 243,500,000
Deferred finance costs, gross				$ 21,000,000
Leucadia | Loans Payable | FXCM Holdings
Unusual or Infrequent Item [Line Items]
Percentage of equity interest of foreign subsidiaries pledged as collateral				65.00%
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
Margin receivable expected to be uncollectible due to foreign currency losses incurred by customers, percentage of customers forgiven			90.00%				97.00%
Margin receivable expected to be uncollectible due to foreign currency losses incurred by customers, percentage of customers required to repay debit balances			10.00%				3.00%
Margin receivable expected to be uncollectible due to foreign currency losses incurred by customers, percentage of debit balances owned by customers required to repay			60.00%				11.00%
Allowance for doubtful accounts receivable, recoveries									9,400,000
Foreign Exchange | Margin Receivable [Member]
Unusual or Infrequent Item [Line Items]
Allowance for doubtful accounts receivable, recoveries							$ (100,000)		(100,000)
Foreign Exchange | Margin Receivable [Member] | Continuing Operations
Unusual or Infrequent Item [Line Items]
Allowance for doubtful accounts receivable, recoveries							$ (300,000)		9,300,000
Bad debt expense						0			257,300,000
Foreign Exchange | Margin Receivable [Member] | Discontinued Operations
Unusual or Infrequent Item [Line Items]
Allowance for doubtful accounts receivable, recoveries						0			100,000
Bad debt expense						$ 0			$ 8,400,000

Debt - Convertible Debt (Detail

Debt - Convertible Debt (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014	Jun. 30, 2013
Interest Expense, Debt [Abstract]
Interest expense - amortization of deferred bond discount			$ 55,373	$ 0
Amortization of deferred financing cost			2,351	1,381
Convertible Debt
Debt Instrument [Line Items]
Liability component — principal	$ 172,500		172,500		$ 172,500
Deferred bond discount	(16,742)		(16,742)		(20,922)	$ (29,100)
Liability component — net carrying value	155,758		155,758		151,578
Equity component	29,101		29,101		$ 29,101	$ 29,100
Interest Expense, Debt [Abstract]
Contractual interest	970	$ 970	2,911	2,911
Interest expense - amortization of deferred bond discount	1,419	1,335	4,180	3,932
Amortization of deferred financing cost	302	302	907	907
Total interest expense	$ 2,691	$ 2,607	$ 7,998	$ 7,750

Debt - Additional Information (

Debt - Additional Information (Details)	Oct. 01, 2015	Jan. 20, 2015USD ($)	Jun. 30, 2013USD ($)$ / shares	Sep. 30, 2015USD ($)	Sep. 30, 2014USD ($)	Sep. 30, 2015USD ($)	Sep. 30, 2014USD ($)	Jan. 28, 2015$ / shares	Jan. 24, 2015	Dec. 31, 2014USD ($)
Debt Instrument [Line Items]
Interest on borrowings				$ 28,974,000	$ 3,028,000	$ 103,824,000	$ 9,121,000
Exercise price of warrants (in dollars per share) | $ / shares			$ 212.40					$ 112
Cost of hedge			$ 29,100,000
Proceeds from sale of warrants			18,600,000
Effective interest rate									39.80%
Common Stock - Class A | Subsequent Event
Debt Instrument [Line Items]
Reverse stock split (in shares)	0.1
Convertible Debt
Debt Instrument [Line Items]
Equity component			29,100,000	29,101,000		29,101,000				$ 29,101,000
Convertible notes				155,758,000		155,758,000				151,578,000
Deferred bond discount			29,100,000	16,742,000		16,742,000				20,922,000
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 | $ / shares			$ 187.62
Convertible notes			$ 144,100,000
Effective interest rate			6.20%
Debt issuance cost			$ 6,000,000
Unamortized debt issuance cost				3,200,000		3,200,000				4,100,000
2.25% Senior Convertible Notes | Convertible Debt | Common Stock - Class A
Debt Instrument [Line Items]
Conversion ratio			0.00532992
Revolving Credit Facility
Debt Instrument [Line Items]
Amount outstanding										$ 25,000,000
Repayments of lines of credit		$ 25,000,000
Interest on borrowings				0	400,000	1,500,000	1,200,000
Weighted average dollar amount of borrowings related to credit agreement				$ 0	$ 27,700,000	$ 1,700,000	$ 37,500,000
Weighted average interest rate				0.00%	2.90%	2.92%	2.68%

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended		3 Months Ended		9 Months Ended
	Sep. 30, 2014	Apr. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Loss Contingencies [Line Items]
Change in control threshold (in percent)					50.00%
Online Courses
Loss Contingencies [Line Items]
Percentage of put options exercised	63.00%	37.00%
Payment on put options	$ 2.3	$ 1.3
Online Courses | General and Administrative Expense
Loss Contingencies [Line Items]
Loss charged to earning for put options				$ 2.3		$ 3.6
Cybersecurity Incident
Loss Contingencies [Line Items]
Professional Fees			$ 0.2

Derivative Financial Instrume64

Derivative Financial Instruments - Gross and Net Fair Value of Derivatives (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Derivative Assets
Total derivatives, gross	$ 7,020	$ 343,070
Netting agreements and cash collateral netting	(6,654)	(342,467)
Total derivatives, net	366	603
Notional	660,882	3,712,626
Derivative Liabilities
Total derivative liabilities	8,670	365,211
Netting agreements and cash collateral netting	(8,670)	(353,543)
Total derivative liabilities	0	11,668
Notional	1,144,531	3,709,701
Discontinued Operations
Derivative Assets
Total derivatives, gross	6,700	342,700
Netting agreements and cash collateral netting	(6,600)	(342,100)
Derivative Liabilities
Total derivative liabilities	8,600	353,100
Netting agreements and cash collateral netting	(8,600)	(353,100)
Continuing Operations
Derivative Assets
Total derivatives, gross	300	400
Netting agreements and cash collateral netting	(100)	(400)
Derivative Liabilities
Total derivative liabilities	100	12,100
Netting agreements and cash collateral netting	(100)	(400)
Exchange traded options
Derivative Assets
Total derivatives, gross	4,429	10,724
Notional	76,440	95,498
Derivative Liabilities
Total derivative liabilities	0	11,422
Notional	0	81,053
CFD contracts
Derivative Assets
Total derivatives, gross	134
Notional	181,480
Derivative Liabilities
Total derivative liabilities	9
Notional	35,352
Futures contracts
Derivative Assets
Total derivatives, gross	2,457	332,346
Notional	402,962	3,617,128
Derivative Liabilities
Total derivative liabilities	8,661	352,703
Notional	$ 1,109,179	3,627,562
OTC options
Derivative Assets
Total derivatives, gross		0
Notional		0
Derivative Liabilities
Total derivative liabilities		1,086
Notional		$ 1,086

Derivative Financial Instrume65

Derivative Financial Instruments - Gains (Losses) from Derivatives (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on derivatives	$ 14,318	$ (27,874)	$ 47,390	$ 6,180
Exchange traded options
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on derivatives	6,049	(5,916)	5,320	14,002
CFD contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on derivatives	3,216	0	(2,131)	0
Futures contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on derivatives	5,053	(21,181)	43,115	(7,428)
OTC options
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on derivatives	0	(777)	1,086	(394)
Income (loss) from continuing operations
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on derivatives	$ 7,500	$ (33,000)	$ 25,800	$ (12,200)

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value Measured on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Financial Assets:
Total derivatives, gross	$ 7,020	$ 343,070
Netting agreements and cash collateral netting	(6,654)	(342,467)
Total due to brokers	366	603
Financial Liabilities:
Total derivative liabilities	8,670	365,211
Netting agreements and cash collateral netting	(8,670)	(353,543)
Due to brokers total	0	11,668
Exchange traded options
Financial Assets:
Total derivatives, gross	4,429	10,724
Financial Liabilities:
Total derivative liabilities	0	11,422
CFD contracts
Financial Assets:
Total derivatives, gross	134
Financial Liabilities:
Total derivative liabilities	9
OTC options
Financial Assets:
Total derivatives, gross		0
Financial Liabilities:
Total derivative liabilities		1,086
Level 1
Financial Assets:
Total assets	0	0
Financial Liabilities:
Total liabilities	0	0
Level 2
Financial Assets:
Total assets	50,561	52,838
Financial Liabilities:
Total liabilities	129,458	176,911
Level 3
Financial Assets:
Total assets	26,240	26,580
Financial Liabilities:
Total liabilities	202,861	0
Fair Value, Measurements, Recurring
Financial Assets:
Trading securities		26
Netting agreements and cash collateral netting	(6,654)	(342,467)
Total due to brokers	366	603
Total assets	366	629
Financial Liabilities:
Customer account liabilities	780,573	1,331,723
Netting agreements and cash collateral netting	(8,670)	(353,543)
Due to brokers total	0	11,668
Securities sold, not yet purchased	3,710	4,239
Total liabilities	1,132,814	1,347,630
Fair Value, Measurements, Recurring | Exchange traded options
Financial Assets:
Total derivatives, gross	4,429	10,724
Financial Liabilities:
Total derivative liabilities		11,422
Fair Value, Measurements, Recurring | CFD contracts
Financial Assets:
Total derivatives, gross	134
Financial Liabilities:
Total derivative liabilities	9
Fair Value, Measurements, Recurring | Futures contracts
Financial Assets:
Total derivatives, gross	2,457	332,346
Financial Liabilities:
Total derivative liabilities	8,661	352,703
Fair Value, Measurements, Recurring | OTC options
Financial Liabilities:
Total derivative liabilities		1,086
Fair Value, Measurements, Recurring | Letter Agreement
Financial Liabilities:
Total derivative liabilities	348,531
Fair Value, Measurements, Recurring | Counterparty and Cash Collateral Netting
Financial Assets:
Netting agreements and cash collateral netting	(6,654)	(342,467)
Financial Liabilities:
Netting agreements and cash collateral netting	(8,670)	(353,543)
Fair Value, Measurements, Recurring | Level 1
Financial Assets:
Trading securities		26
Total derivatives, gross	6,886	343,070
Total assets	6,886	343,096
Financial Liabilities:
Customer account liabilities	0	0
Total derivative liabilities	8,661	364,125
Securities sold, not yet purchased	3,710	4,239
Total liabilities	12,371	368,364
Fair Value, Measurements, Recurring | Level 1 | Exchange traded options
Financial Assets:
Total derivatives, gross	4,429	10,724
Financial Liabilities:
Total derivative liabilities		11,422
Fair Value, Measurements, Recurring | Level 1 | CFD contracts
Financial Assets:
Total derivatives, gross	0
Financial Liabilities:
Total derivative liabilities	0
Fair Value, Measurements, Recurring | Level 1 | Futures contracts
Financial Assets:
Total derivatives, gross	2,457	332,346
Financial Liabilities:
Total derivative liabilities	8,661	352,703
Fair Value, Measurements, Recurring | Level 1 | OTC options
Financial Liabilities:
Total derivative liabilities		0
Fair Value, Measurements, Recurring | Level 1 | Letter Agreement
Financial Liabilities:
Total derivative liabilities	0
Fair Value, Measurements, Recurring | Level 2
Financial Assets:
Trading securities		0
Total derivatives, gross	134	0
Total assets	134	0
Financial Liabilities:
Customer account liabilities	780,573	1,331,723
Total derivative liabilities	9	1,086
Securities sold, not yet purchased	0	0
Total liabilities	780,582	1,332,809
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	134
Financial Liabilities:
Total derivative liabilities	9
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 Liabilities:
Total derivative liabilities		1,086
Fair Value, Measurements, Recurring | Level 2 | Letter Agreement
Financial Liabilities:
Total derivative liabilities	0
Fair Value, Measurements, Recurring | Level 3
Financial Assets:
Trading securities		0
Total derivatives, gross	0	0
Total assets	0	0
Financial Liabilities:
Customer account liabilities	0	0
Total derivative liabilities	0	0
Securities sold, not yet purchased	0	0
Total liabilities	348,531	0
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
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 Liabilities:
Total derivative liabilities		$ 0
Fair Value, Measurements, Recurring | Level 3 | Letter Agreement
Financial Liabilities:
Total derivative liabilities	$ 348,531

Fair Value Measurements - Fai67

Fair Value Measurements - Fair Value Assumptions (Details) $ in Millions	9 Months Ended
	Sep. 30, 2015USD ($)
Letter Agreement
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Effect of 10% increase in expected volatility rate, decrease in fair value	$ 35.3
Effect of 10% decrease in expected volatility rate, increase in fair value	$ 40.9
Option-Pricing Method
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Term (years)	2 years 8 months 12 days
Volatility	58.90%
Risk-free rate	0.80%
Dividend yield	0.00%
Reliance placed on public indication of value	100.00%

Fair Value Measurements - Fai68

Fair Value Measurements - Fair Value by Balance Sheet Groupings (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Level 1
Financial Assets:
Restricted time deposits		$ 0
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
Notes receivable	0	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
Revolving credit agreement		0
Total liabilities	0	0
Level 2
Financial Assets:
Restricted time deposits		8,341
Due from brokers — unsettled spot FX	24,219	14,635
Due from brokers — unsettled common stock	3,054	3,730
Due from brokers — excess cash collateral	16,963	18,330
Equity method investments	0	0
Notes receivable	0	0
Exchange memberships	6,325	7,802
Total assets	50,561	52,838
Financial Liabilities:
Due to brokers — unsettled spot FX	81	4,645
Senior convertible notes	129,377	147,266
Credit Agreement	0
Revolving credit agreement		25,000
Total liabilities	129,458	176,911
Level 3
Financial Assets:
Restricted time deposits		0
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	18,359	17,199
Notes receivable	7,881	9,381
Exchange memberships	0	0
Total assets	26,240	26,580
Financial Liabilities:
Due to brokers — unsettled spot FX	0	0
Senior convertible notes	0	0
Credit Agreement	202,861
Revolving credit agreement		0
Total liabilities	202,861	0
Carrying Value
Financial Assets:
Restricted time deposits		8,341
Due from brokers — unsettled spot FX	24,219	14,635
Due from brokers — unsettled common stock	3,054	3,730
Due from brokers — excess cash collateral	16,963	18,330
Equity method investments	8,887	10,007
Notes receivable	7,881	9,381
Exchange memberships	5,770	6,429
Total assets	66,774	70,853
Financial Liabilities:
Due to brokers — unsettled spot FX	81	4,645
Senior convertible notes	155,758	151,578
Credit Agreement	145,330
Revolving credit agreement		25,000
Total liabilities	301,169	181,223
Fair Value
Financial Assets:
Restricted time deposits		8,341
Due from brokers — unsettled spot FX	24,219	14,635
Due from brokers — unsettled common stock	3,054	3,730
Due from brokers — excess cash collateral	16,963	18,330
Equity method investments	18,359	17,199
Notes receivable	7,881	9,381
Exchange memberships	6,325	7,802
Total assets	76,801	79,418
Financial Liabilities:
Due to brokers — unsettled spot FX	81	4,645
Senior convertible notes	129,377	147,266
Credit Agreement	202,861
Revolving credit agreement		25,000
Total liabilities	$ 332,319	$ 176,911

Fair Value Measurements - Level

Fair Value Measurements - Level 3 Rollforward (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2015USD ($)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	$ 0
Additions	94,436
Net Unrealized Loss	254,095
Ending balance	348,531
Letter Agreement
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	0
Additions	94,436
Net Unrealized Loss	254,095
Ending balance	$ 348,531

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details) $ / shares in Units, $ in Millions	Oct. 01, 2015	Apr. 30, 2015$ / sharesshares	Apr. 15, 2015USD ($)$ / sharesshares	Jan. 28, 2015Right$ / shares	Jun. 30, 2013$ / shares
Class of Stock [Line Items]
Preferred stock, conversion ratio				0.01
Exercise price of right per thousandth preferred share (in dollars per share)				$ 112	$ 212.40
Beneficial ownership in outstanding common stock threshold (percentage)				10.00%
Number of shares available under Option Agreement (in shares) | shares		56,934
Exercise price per share under Option Agreement (in dollars per share)		$ 22.50	$ 22.50
Fair value of options at issuance | $			$ 0.3
Common Stock - Class A
Class of Stock [Line Items]
Common stock, dividend declared, rights per share | Right				1
Number of shares available under Option Agreement (in shares) | shares			56,934
Common Stock - Class A | Subsequent Event
Class of Stock [Line Items]
Reverse stock split (in shares)	0.1

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Tax Disclosure [Abstract]
Effective tax rate	0.30%	30.20%	(35.90%)	(109.00%)

Litigation - Additional Informa

Litigation - Additional Information (Detail) £ in Millions	Jun. 15, 2015USD ($)	Sep. 30, 2015USD ($)	Feb. 28, 2015USD ($)	Jul. 31, 2014USD ($)	Jun. 30, 2014USD ($)	Feb. 28, 2014USD ($)	Feb. 28, 2014GBP (£)	Jan. 31, 2014USD ($)
Loss Contingencies [Line Items]
Range of loss, min		$ 0
Range of loss, max		6,000,000
US | US vs Revelation Forex Fund, Kevin G. White, and Related Entities
Loss Contingencies [Line Items]
Damages sought (in excess of)	$ 2,000,000							$ 3,800,000
US | US vs. National Futures Association
Loss Contingencies [Line Items]
Settlement amount				$ 200,000
US | US vs Commodity Futures Trading Commission
Loss Contingencies [Line Items]
Settlement amount		700,000
Settlement, disgorged commissions and fees		$ 100,000
UK LTD and FSL | FCA Draft Warning Notice
Loss Contingencies [Line Items]
Settlement amount						$ 6,600,000	£ 4
UK LTD and FSL | Restitution to Affected Clients | FCA Draft Warning Notice
Loss Contingencies [Line Items]
Settlement amount			$ 700,000		$ 1,800,000
UK LTD and FSL | Restitution to Affected Clients | FCA Draft Warning Notice | Maximum
Loss Contingencies [Line Items]
Settlement amount						$ 9,900,000

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail)	Oct. 01, 2015
Common Stock - Class A | Subsequent Event
Subsequent Event [Line Items]
Reverse stock split (in shares)	0.1