MarketAxess (MKTX) 10-Q 23 Oct 15 2015 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2015	Oct. 22, 2015
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q3
Trading Symbol	MKTX
Entity Registrant Name	MARKETAXESS HOLDINGS INC
Entity Central Index Key	1,278,021
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		37,291,741

Consolidated Statements of Fina

Consolidated Statements of Financial Condition - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
ASSETS
Cash and cash equivalents	$ 160,376	$ 168,924
Securities available-for-sale, at fair value	95,516	64,863
Accounts receivable, net of allowance of $39 and $3 as of September 30, 2015 and December 31, 2014, respectively	49,280	33,836
Goodwill and intangible assets, net of accumulated amortization	64,712	66,419
Furniture, equipment, leasehold improvements and capitalized software, net of accumulated depreciation and amortization	31,027	32,185
Prepaid expenses and other assets	7,173	6,685
Deferred tax assets, net	8,238	6,972
Total assets	416,322	379,884
Liabilities
Accrued employee compensation	22,838	25,310
Income and other tax liabilities	4,410	5,940
Deferred revenue	2,215	2,465
Accounts payable, accrued expenses and other liabilities	13,388	11,961
Total liabilities	$ 42,851	$ 45,676
Commitments and Contingencies (Note 10)
Stockholders’ equity
Additional paid-in capital	$ 317,617	$ 307,059
Treasury stock - Common stock voting, at cost, 2,379,545 and 2,141,344 shares as of September 30, 2015 and December 31, 2014, respectively	(90,272)	(70,247)
Retained earnings	150,975	101,813
Accumulated other comprehensive loss	(4,969)	(4,537)
Total stockholders’ equity	373,471	334,208
Total liabilities and stockholders’ equity	$ 416,322	$ 379,884
Undefined Preferred Stock [Member]
Stockholders’ equity
Preferred stock
Series A Preferred Stock [Member]
Stockholders’ equity
Preferred stock
Voting Common Stock [Member]
Stockholders’ equity
Common stock	$ 120	$ 120

Consolidated Statements of Fin3

Consolidated Statements of Financial Condition (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Allowance for accounts receivable	$ 39	$ 3
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	4,855,000	4,855,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.003	$ 0.003
Common stock, shares authorized	110,000,000	110,000,000
Common stock, shares issued	39,687,461	39,460,066
Common stock, shares outstanding	37,307,916	37,318,722
Treasury stock, shares	2,379,545	2,141,344
Series A Preferred Stock [Member]
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	110,000	110,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common Stock Non-Voting [Member]
Common stock, par value	$ 0.003	$ 0.003
Common stock, shares authorized	10,000,000	10,000,000
Common stock, shares issued	0	0
Common stock, shares outstanding	0	0

Consolidated Statements of Oper

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
Commissions	$ 65,178	$ 54,462	$ 198,608	$ 160,766
Information and post-trade services	7,671	7,600	22,982	23,641
Technology products and services	683	1,562	2,865	5,585
Investment income	248	132	621	416
Other	412	489	1,378	2,199
Total revenues	74,192	64,245	226,454	192,607
Expenses
Employee compensation and benefits	21,002	18,589	62,769	55,619
Depreciation and amortization	4,642	4,482	13,857	12,954
Technology and communications	3,891	4,359	12,196	13,300
Professional and consulting fees	3,210	3,514	9,503	10,912
Occupancy	1,246	1,127	3,470	3,318
Marketing and advertising	1,304	1,331	4,260	4,340
General and administrative	3,544	2,575	9,485	7,117
Total expenses	38,839	35,977	115,540	107,560
Income before income taxes	35,353	28,268	110,914	85,047
Provision for income taxes	12,638	10,764	39,368	31,877
Net income	$ 22,715	$ 17,504	$ 71,546	$ 53,170
Net income per common share
Basic	$ 0.62	$ 0.47	$ 1.95	$ 1.44
Diluted	0.60	0.46	1.90	1.40
Cash dividends declared per common share	$ 0.20	$ 0.16	$ 0.60	$ 0.48
Weighted average shares outstanding
Basic	36,681	36,856	36,695	36,997
Diluted	37,643	37,805	37,636	37,947

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 22,715	$ 17,504	$ 71,546	$ 53,170
Net cumulative translation adjustment and foreign currency exchange hedge, net of tax of $(69), $(96), $(229) and $(334), respectively	(105)	(111)	(420)	(492)
Net unrealized (loss) gain on securities available-for-sale, net of tax of $(4), $(16), $(7) and $16, respectively	(6)	(27)	(12)	30
Less: reclassification adjustment for realized gain from securities available-for-sale included in Other revenues, net of tax of $0, $(7), $0 and $(19), respectively		(12)		(35)
Net change in unrealized (loss) gain on securities available-for-sale, net of tax	(6)	(39)	(12)	(5)
Comprehensive Income	$ 22,604	$ 17,354	$ 71,114	$ 52,673

Consolidated Statements of Com6

Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Statement Of Income And Comprehensive Income [Abstract]
Foreign currency exchange hedge, tax benefit	$ (69)	$ (96)	$ (229)	$ (334)
Securities available-for-sale, tax expense (benefit)	(4)	(16)	(7)	16
Sale of securities available- for-sale included in Other Income, tax benefit	$ 0	$ (7)	$ 0	$ (19)

Consolidated Statements of Chan

Consolidated Statements of Changes in Stockholders' Equity - 9 months ended Sep. 30, 2015 - USD ($) $ in Thousands	Total	Common Stock Voting [Member]	Additional Paid-in Capital [Member]	Treasury Stock - Common Stock Voting [Member]	Retained Earnings (Deficit) [Member]	Accumulated Other Comprehensive Loss [Member]
Beginning Balance at Dec. 31, 2014	$ 334,208	$ 120	$ 307,059	$ (70,247)	$ 101,813	$ (4,537)
Net income	71,546				71,546
Cumulative translation adjustment and foreign currency exchange hedge, net of tax	(420)					(420)
Unrealized net loss on securities available-for-sale, net of tax	(12)					(12)
Stock-based compensation	9,276		9,276
Exercise of stock options	1,530		1,530
Withholding tax payments on restricted stock vesting and stock option exercises	(4,450)		(4,450)
Excess tax benefits from stock-based compensation	4,202		4,202
Repurchases of common stock	(20,025)			(20,025)
Cash dividend on common stock	(22,384)				(22,384)
Ending Balance at Sep. 30, 2015	$ 373,471	$ 120	$ 317,617	$ (90,272)	$ 150,975	$ (4,969)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Cash flows from operating activities
Net income	$ 71,546	$ 53,170
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	13,857	12,954
Stock-based compensation expense	9,276	7,179
Deferred taxes	(1,250)	1,575
Other	1,638	1,482
Changes in operating assets and liabilities:
(Increase) in accounts receivable	(15,595)	(2,321)
(Increase) decrease in prepaid expenses and other assets	(347)	1,245
(Decrease) in accrued employee compensation	(2,472)	(5,617)
(Decrease) in income and other tax liabilities	(1,309)	(110)
(Decrease) increase in deferred revenue	(250)	558
Increase (decrease) in accounts payable, accrued expenses and other liabilities	1,244	(1,526)
Net cash provided by operating activities	76,338	68,589
Securities available-for-sale:
Proceeds from maturities	25,048	13,536
Purchases	(57,175)	(4,181)
Purchases of furniture, equipment and leasehold improvements	(3,730)	(4,002)
Capitalization of software development costs	(7,517)	(7,412)
Other	(141)	595
Net cash (used in) investing activities	(43,515)	(1,464)
Cash flows from financing activities
Cash dividend on common stock	(22,201)	(18,062)
Exercise of stock options	1,530	1,390
Withholding tax payments on restricted stock vesting and stock option exercises	(4,450)	(5,008)
Excess tax benefits from stock-based compensation	4,202	3,203
Repurchases of common stock	(20,025)	(25,442)
Other		(42)
Net cash (used in) financing activities	(40,944)	(43,961)
Effect of exchange rate changes on cash and cash equivalents	(427)	(755)
Cash and cash equivalents
Net (decrease) increase for the period	(8,548)	22,409
Beginning of period	168,924	132,691
End of period	$ 160,376	$ 155,100

Organization and Principal Busi

Organization and Principal Business Activity	9 Months Ended
	Sep. 30, 2015
Accounting Policies [Abstract]
Organization and Principal Business Activity	1. Organization and Principal Business Activity MarketAxess Holdings Inc. (the “Company” or “MarketAxess”) was incorporated in the State of Delaware on April 11, 2000. Through its subsidiaries, the Company operates an electronic trading platform for corporate bonds and other types of fixed-income instruments through which the Company’s institutional investor clients can access liquidity provided by its broker-dealer and other institutional clients. The Company’s multi-dealer trading platform allows its institutional investor clients to simultaneously request competitive, executable bids or offers from multiple broker-dealers, and to execute trades with the broker-dealer of their choice. The Company’s trading platform provides access to global liquidity in U.S. high-grade corporate bonds, emerging markets and high-yield bonds, European bonds, U.S. agency bonds, credit derivatives and other fixed-income securities. The Company also executes certain bond transactions between and among institutional investor and broker-dealer clients on a matched principal basis by serving as counterparty to both the buyer and the seller in trades which then settle through a third-party clearing broker. The Company provides fixed-income market data, analytics and compliance tools that help its clients make trading decisions. The Company also provides trade matching and regulatory transaction reporting services to the securities markets. In addition, the Company provides technology solutions and professional consulting services to fixed-income industry participants.

Significant Accounting Policies

Significant Accounting Policies	9 Months Ended
	Sep. 30, 2015
Accounting Policies [Abstract]
Significant Accounting Policies	2. Significant Accounting Policies Basis of Presentation The consolidated financial statements include the accounts of the Company and its subsidiaries. All intercompany transactions and balances have been eliminated. These consolidated financial statements are unaudited and should be read in conjunction with the audited consolidated financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014. The consolidated financial information as of December 31, 2014 has been derived from audited financial statements not included herein. These unaudited consolidated financial statements are prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) and the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) with respect to Form 10-Q and reflect all adjustments that, in the opinion of management, are normal and recurring, and that are necessary for a fair statement of the results for the interim periods presented. In accordance with such rules and regulations, certain disclosures that are normally included in annual financial statements have been omitted. Interim period operating results may not be indicative of the operating results for a full year. Cash and Cash Equivalents Cash and cash equivalents includes cash and money market instruments that are primarily maintained at one major global bank. Given this concentration, the Company is exposed to certain credit risk in relation to its deposits at this bank. The Company defines cash equivalents as short-term interest-bearing investments with maturities at the time of purchase of three months or less. Securities Available-for-Sale The Company classifies its marketable securities as available-for-sale securities. Unrealized marketable securities gains and losses, net of taxes, are included in accumulated other comprehensive loss in the Consolidated Statements of Financial Condition. Realized gains and losses are recorded in the Consolidated Statements of Operations in other revenues. For the purpose of computing realized gains and losses, cost is determined on a specific identification basis. The Company assesses whether an other-than-temporary impairment loss on the investments has occurred due to declines in fair value or other market conditions. The portion of an other-than-temporary impairment related to credit loss is recorded as a charge in the Consolidated Statements of Operations. The remainder is recognized in accumulated other comprehensive loss if the Company does not intend to sell the security and it is more likely than not that the Company will not be required to sell the security prior to recovery. No charges for other-than-temporary losses were recorded during the nine months ended September 30, 2015 and 2014. Fair Value Financial Instruments 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.” A three-tiered hierarchy for determining fair value has been established that prioritizes inputs to valuation techniques used in fair value calculations. The three levels of inputs are defined as Level 1 (unadjusted quoted prices for identical assets or liabilities in active markets), Level 2 (inputs that are observable in the marketplace other than those inputs classified in Level 1) and Level 3 (inputs that are unobservable in the marketplace). The Company’s financial assets and liabilities measured at fair value on a recurring basis consist of its money market funds, securities available-for-sale portfolio and foreign currency forward contracts. All other financial instruments are short-term in nature and the carrying amount is reported in the Consolidated Statements of Financial Condition approximate fair value. Allowance for Doubtful Accounts All accounts receivable have contractual maturities of less than one year and are derived from trading-related fees and commissions and revenues from products and services. The Company continually monitors collections and payments from its customers and maintains an allowance for doubtful accounts. The allowance for doubtful accounts is based upon the historical collection experience and specific collection issues that have been identified. Additions to the allowance for doubtful accounts are charged to bad debt expense, which is included in general and administrative expense in the Company’s Consolidated Statements of Operations. Depreciation and Amortization Fixed assets are carried at cost less accumulated depreciation. The Company uses the straight-line method of depreciation over three to seven years. The Company amortizes leasehold improvements on a straight-line basis over the lesser of the life of the improvement or the remaining term of the lease. Software Development Costs The Company capitalizes certain costs associated with the development of internal use software, including among other items, employee compensation and related benefits and third party consulting costs at the point at which the conceptual formulation, design and testing of possible software project alternatives have been completed. Once the product is ready for its intended use, such costs are amortized on a straight-line basis over three years. The Company reviews the amounts capitalized for impairment whenever events or changes in circumstances indicate that the carrying amounts of the assets may not be recoverable. Cash Provided as Collateral Cash is provided as collateral for broker-dealer clearing accounts. Cash provided as collateral is included in prepaid expenses and other assets in the Consolidated Statements of Financial Condition. Foreign Currency Translation and Forward Contracts Assets and liabilities denominated in foreign currencies are translated using exchange rates at the end of the period; revenues and expenses are translated at average monthly rates. Gains and losses on foreign currency translation are a component of accumulated other comprehensive loss in the Consolidated Statements of Financial Condition. Transaction gains and losses are recorded in general and administrative expense in the Consolidated Statements of Operations. The Company enters into foreign currency forward contracts to hedge its net investment in its U.K. subsidiaries. Gains and losses on these transactions are included in accumulated other comprehensive loss in the Consolidated Statements of Financial Condition. Revenue Recognition The majority of the Company’s revenues are derived from commissions for trades executed on its platform and distribution fees that are billed to its broker-dealer clients on a monthly basis. The Company also derives revenues from information and post-trade services, technology products and services, investment income and other income. Commission revenue. Commissions are generally calculated as a percentage of the notional dollar volume of bonds traded on the platform and vary based on the type, size, yield and maturity of the bond traded. Under the Company’s transaction fee plans, bonds that are more actively traded or that have shorter maturities are generally charged lower commissions, while bonds that are less actively traded or that have longer maturities generally command higher commissions. For trades that the Company executes between and among institutional investor and broker-dealer clients on a matched principal basis by serving as counterparty to both the buyer and the seller, the Company earns the commission through the difference in price between the two matched principal trades. Fee programs for certain products include distribution fees which are recognized monthly. Information and post-trade services. The Company generates revenue from information services provided to our broker-dealer clients, institutional investor clients and data-only subscribers. Information services are invoiced monthly, quarterly or annually. When billed in advance, revenues are deferred and recognized monthly on a straight-line basis. The Company also generates revenue from regulatory transaction reporting and trade matching services. Revenue is recognized in the period the services are provided. Technology products and services. The Company generates revenues from professional consulting services, technology software licenses and maintenance and support services (referred to as post-contract technical support or “PCS”). Revenue is generally recognized when persuasive evidence of an arrangement exists, delivery has occurred, the fee is fixed or determinable and collection is considered probable. The Company enters into time and materials professional consulting contracts unrelated to any software product. Revenue for time and materials contracts is recognized as services are performed. The Company generally sells software license subscriptions on a stand-alone basis or software licenses and PCS together as part of multiple-element arrangements. Revenue for software license subscriptions is recognized ratably over the contract period. For arrangements that include multiple elements, generally software licenses and PCS, the Company allocates and defers revenue for the undelivered items based on vendor specific objective evidence (“VSOE”) of the fair value of the undelivered elements and recognizes the difference between the total arrangement fee and the amount deferred for the undelivered items as license revenue. When VSOE does not exist for undelivered items, the entire arrangement fee is recognized ratably over the performance period. For PCS, the term is typically one year and revenue is recognized over the duration of the arrangement on a straight-line basis. Initial set-up fees. The Company enters into agreements with its broker-dealer clients pursuant to which the Company provides access to its platform through a non-exclusive and non-transferable license. Broker-dealer clients may pay an initial set-up fee, which is typically due and payable upon execution of a dealer agreement. The initial set-up fee, if any, varies by agreement. Revenue is recognized over the initial term of the agreement, which is generally two years. Initial set-up fees are reported in other income in the Consolidated Statements of Operations. Stock-Based Compensation The Company measures and recognizes compensation expense for all share-based payment awards based on their estimated fair values measured as of the grant date. These costs are recognized as an expense in the Consolidated Statements of Operations over the requisite service period, which is typically the vesting period, with an offsetting increase to additional paid-in capital. Income Taxes Income taxes are accounted for using the asset and liability method. Deferred income taxes reflect the net tax effects of temporary differences between the financial reporting and tax bases of assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when such differences are expected to reverse. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. A valuation allowance is recognized against deferred tax assets if it is more likely than not that such assets will not be realized in future years. The Company recognizes interest and penalties related to unrecognized tax benefits in general and administrative expenses in the Consolidated Statements of Operations. Business Combinations, Goodwill and Intangible Assets Business combinations are accounted for under the purchase method of accounting. The total cost of an acquisition is allocated to the underlying net assets based on their respective estimated fair values. The excess of the purchase price over the estimated fair values of the net assets acquired is recorded as goodwill. Determining the fair value of certain assets acquired and liabilities assumed is judgmental in nature and often involves the use of significant estimates and assumptions, including assumptions with respect to future cash flows, discount rates, growth rates and asset lives. The Company operates as a single reporting unit. Subsequent to an acquisition, goodwill no longer retains its identification with a particular acquisition, but instead becomes identifiable with the entire reporting unit. As a result, all of the fair value of the Company is available to support the value of goodwill. An impairment review of goodwill is performed on an annual basis, at year-end, or more frequently if circumstances change. Intangible assets with definite lives, including purchased technologies, customer relationships and other intangible assets, are amortized on a straight-line basis over their estimated useful lives, ranging from three to 15 years. Intangible assets are assessed for impairment when events or circumstances indicate the existence of a possible impairment. Earnings Per Share Basic earnings per share is computed by dividing the net income attributable to common stock by the weighted-average number of shares of common stock outstanding during the period. For purposes of computing diluted earnings per share, the weighted-average shares outstanding of common stock reflects the dilutive effect that could occur if convertible securities or other contracts to issue common stock were converted into or exercised for common stock. Use of Estimates The preparation of financial statements in conformity with 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 financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Recent Accounting Pronouncements In August 2015, the Financial Accounting Standards Board issued Accounting Standards Update (“ASU”) No. 2015-14, “Revenue from Contracts with Customers”, which will replace most of the existing revenue recognition guidance in GAAP. The core principle of the ASU is that an entity should recognize revenue for the transfer of goods or services equal to the amount that it expects to be entitled to receive for those goods or services. The ASU requires additional disclosure about the nature, amount, timing and uncertainty of revenue and cash flows arising from customer contracts, including significant judgments and changes in judgments. The ASU will be effective for the Company beginning January 1, 2018 and allows for both retrospective and prospective methods of adoption. The Company is in the process of determining the method of adoption and assessing the impact of this ASU on the Company’s Consolidated Financial Statements.

Net Capital Requirements

Net Capital Requirements	9 Months Ended
	Sep. 30, 2015
Net Capital [Abstract]
Net Capital Requirements	3. Net Capital Requirements Certain U.S. subsidiaries of the Company are registered as a broker-dealer or swap execution facility and therefore are subject to the applicable rules and regulations of the SEC and the Commodity Futures Trading Commission. These rules contain minimum net capital requirements, as defined in the applicable regulations, and also may require a significant part of the registrants’ assets be kept in relatively liquid form. Certain of the Company’s foreign subsidiaries are regulated by the Financial Conduct Authority in the U.K. or Ontario Securities Commission in Canada and must maintain financial resources, as defined in the applicable regulations, in excess of the applicable financial resources requirement. As of September 30, 2015, each of the Company’s subsidiaries that are subject to these regulations had net capital or financial resources in excess of their minimum requirements. As of September 30, 2015, the Company’s subsidiaries maintained aggregate net capital and financial resources that was $102.6 million in excess of the required levels of $9.0 million. Each of the Company’s U.S. and foreign regulated subsidiaries are subject to local regulations which generally prohibit repayment of borrowings from the Company or affiliates, paying cash dividends, making loans to the Company or affiliates or otherwise entering into transactions that result in a significant reduction in regulatory net capital or financial resources without prior notification to or approval from such regulated entity’s principal regulator.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurements	4. Fair Value Measurements The following table summarizes the valuation of the Company’s assets and liabilities measured at fair value as categorized based on the hierarchy described in Note 2. Level 1 Level 2 Level 3 Total (In thousands) As of September 30, 2015 Money market funds $ 51,175 $ — $ — $ 51,175 Securities available-for-sale Municipal securities — 4,274 — 4,274 Corporate bonds — 91,242 — 91,242 Foreign currency forward position — 186 — 186 Total $ 51,175 $ 95,702 $ — $ 146,877 As of December 31, 2014 Money market funds $ 62,126 $ — $ — $ 62,126 Securities available-for-sale Municipal securities — 11,696 — 11,696 Corporate bonds — 53,167 — 53,167 Foreign currency forward position — 103 — 103 Total $ 62,126 $ 64,966 $ — $ 127,092 Securities classified within Level 2 were valued using a market approach utilizing prices and other relevant information generated by market transactions involving comparable assets. The foreign currency forward contracts are classified within Level 2 as the valuation inputs are based on quoted market prices. There were no financial assets classified within Level 3 during the nine months ended September 30, 2015 and 2014. The Company enters into foreign currency forward contracts to hedge the exposure to variability in certain foreign currency cash flows resulting from the net investment in the Company’s U.K. subsidiaries. The Company designates each foreign currency forward contract as a hedge and assesses the risk management objective and strategy, including identification of the hedging instrument, the hedged item and the risk exposure and how effectiveness is to be assessed prospectively and retrospectively. These hedges are typically for a one-month period and are used to limit exposure to foreign currency exchange rate fluctuations. The fair value of each asset is included in accounts receivable and the fair value of each liability is included in accounts payable in the Consolidated Statements of Financial Condition. Gains or losses on foreign currency forward contracts designated as hedges are included in accumulated other comprehensive loss in the Consolidated Statements of Financial Condition. A summary of the Company’s foreign currency forward position is as follows: As of September 30, 2015 December 31, 2014 (In thousands) Notional value $ 42,297 $ 32,089 Fair value of notional 42,111 31,986 Fair value of the asset $ 186 $ 103 The following is a summary of the Company’s securities available-for-sale: Gross Gross Estimated Amortized unrealized unrealized fair cost gains losses value (In thousands) As of September 30, 2015 Municipal securities $ 4,272 $ 2 $ — $ 4,274 Corporate bonds 91,237 73 (68 ) 91,242 Total securities available-for-sale $ 95,509 $ 75 $ (68 ) $ 95,516 As of December 31, 2014 Municipal securities $ 11,693 $ 5 $ (2 ) $ 11,696 Corporate bonds 53,146 50 (29 ) 53,167 Total securities available-for-sale $ 64,839 $ 55 $ (31 ) $ 64,863 The following table summarizes the contractual maturities of securities available-for-sale: As of September 30, 2015 December 31, 2014 (In thousands) Less than one year $ 42,107 $ 36,062 Due in 1 - 5 years 53,409 28,801 Total securities available-for-sale $ 95,516 $ 64,863 Proceeds from the sales and maturities of securities available-for-sale during the nine months ended September 30, 2015 and 2014 were $25.0 million and $13.5 million, respectively. The following table provides fair values and unrealized losses on securities available-for-sale and by the aging of the securities’ continuous unrealized loss position as of September 30, 2015 and December 31, 2014: Less than Twelve Months Twelve Months or More Total Estimated Gross Estimated Gross Estimated Gross fair unrealized fair unrealized fair unrealized value losses value losses value losses (In thousands) As of September 30, 2015 Municipal securities $ — $ — $ — $ — $ — $ — Corporate bonds 37,085 (68 ) — — 37,085 (68 ) Total $ 37,085 $ (68 ) $ — $ — $ 37,085 $ (68 ) As of December 31, 2014 Municipal securities $ 2,139 $ (2 ) $ — $ — $ 2,139 $ (2 ) Corporate bonds 20,487 (29 ) — — 20,487 (29 ) Total $ 22,626 $ (31 ) $ — $ — $ 22,626 $ (31 )

Goodwill and Intangible Assets

Goodwill and Intangible Assets	9 Months Ended
	Sep. 30, 2015
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	5. Goodwill and Intangible Assets Goodwill and intangible assets with indefinite lives was $59.7 million as of both September 30, 2015 and December 31, 2014. Intangible assets that are subject to amortization, including the related accumulated amortization, are comprised of the following: September 30, 2015 December 31, 2014 Cost Accumulated Amortization Net Carrying Amount Cost Accumulated Amortization Net Carrying Amount (In thousands) Technology $ 5,770 $ (5,076 ) $ 694 $ 5,770 $ (3,826 ) $ 1,944 Customer relationships 5,674 (1,464 ) 4,210 5,682 (1,183 ) 4,499 Non-competition agreements 380 (327 ) 53 380 (232 ) 148 Tradenames 370 (328 ) 42 370 (253 ) 117 Total $ 12,194 $ (7,195 ) $ 4,999 $ 12,202 $ (5,494 ) $ 6,707 Amortization expense associated with identifiable intangible assets was $1.7 million for both the nine months ended September 30, 2015 and 2014. Estimated total amortization expense is $2.3 million for 2015, $0.7 million for 2016 and $0.4 million for each of 2017, 2018 and 2019.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2015
Income Tax Disclosure [Abstract]
Income Taxes	6. Income Taxes The provision for income taxes consists of the following: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 (In thousands) Current: Federal $ 11,041 $ 9,280 $ 28,131 $ 22,297 State and local 2,036 1,583 5,234 4,356 Foreign 1,234 227 3,189 520 Total current provision 14,311 11,090 36,554 27,173 Deferred: Federal (1,246 ) (354 ) 2,658 3,979 State and local (209 ) (73 ) 420 512 Foreign (218 ) 101 (264 ) 213 Total deferred provision (1,673 ) (326 ) 2,814 4,704 Provision for income taxes $ 12,638 $ 10,764 $ 39,368 $ 31,877 The following is a summary of the Company’s net deferred tax assets: As of September 30, 2015 December 31, 2014 Deferred tax assets and liabilities $ 14,053 $ 12,468 Valuation allowance (7,334 ) (7,428 ) Deferred tax assets, net $ 6,719 $ 5,040 The Company or one of its subsidiaries files U.S. federal, state and foreign income tax returns. Income tax returns for New York City (through 2003) and state (through 2009) and Connecticut state (through 2003) tax returns have been audited. Examinations of the Company’s federal tax returns for 2011 and 2012 and New York State tax returns for 2010 through 2013 are currently underway. The Company cannot estimate when the examinations will conclude or the impact such examinations will have on the Company’s Consolidated Financial Statements, if any. The Company has determined that unremitted earnings of the Company’s foreign subsidiaries are considered indefinitely reinvested outside of the United States.

Stock-Based Compensation Plans

Stock-Based Compensation Plans	9 Months Ended
	Sep. 30, 2015
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation Plans	7. Stock-Based Compensation Plans Stock-based compensation expense for the nine months ended September 30, 2015 and 2014 was as follows: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 (In thousands) Employees $ 2,958 $ 2,231 $ 8,596 $ 6,503 Non-employee directors 294 298 680 676 Total stock-based compensation $ 3,252 $ 2,529 $ 9,276 $ 7,179 The Company records stock-based compensation for employees in employee compensation and benefits and for non-employee directors in general and administrative expenses in the Consolidated Statements of Operations. In January 2015, the Company granted 119,981 stock options and a 116,659 performance stock award to the Company’s Chief Executive Officer in consideration for entering into a new employment agreement. The exercise price for the shares of the Company’s common stock underlying the option award is $88.25, which is equal to 125% of the fair market value of the common stock on the grant date. Subject to the Chief Executive Officer’s continued employment with the Company through the applicable vesting date, one-third of the options under the option award will vest and become exercisable on each of January 15, 2018, 2019 and 2020. The performance stock award provides that the number of performance shares earned by the Chief Executive Officer will be based on the Company’s achievement of certain performance levels. Subject to the Chief Executive Officer’s continued employment, if only the minimum performance level is achieved, then the stock will vest 100% on January 15, 2020, and if any performance level above the minimum level is achieved then the stock will vest . In addition to the grants above, the Company granted to employees and non-employee directors restricted stock or restricted stock units of 111,089 shares, performance shares with an expected pay-out at target of 28,520 shares of common stock and 669 options to purchase shares of common stock during the nine months ended September 30, 2015. The fair value of the restricted stock and performance share awards was based on a weighted-average grant date fair value per share of $74.44 and $70.60, respectively. Based on the Black-Scholes option pricing model, the weighted-average fair value for each option granted was $36.46 per share. The awards vest over a three or five year period and had an aggregate grant date fair value of $8.3 million. As of September 30, 2015, the total unrecognized compensation cost related to all non-vested awards was $20.7 million. That cost is expected to be recognized over a weighted-average period of 2.3 years.

Earnings Per Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2015
Earnings Per Share [Abstract]
Earnings Per Share	8. Earnings Per Share The following table sets forth the computation of basic and diluted earnings per common share: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 (In thousands, except per share amounts) Net income $ 22,715 $ 17,504 $ 71,546 $ 53,170 Basic weighted average shares outstanding 36,681 36,856 36,695 36,997 Dilutive effect of stock options and restricted stock 962 949 941 950 Diluted weighted average shares outstanding 37,643 37,805 37,636 37,947 Basic earnings per share $ 0.62 $ 0.47 $ 1.95 $ 1.44 Diluted earnings per share $ 0.60 $ 0.46 $ 1.90 $ 1.40 Stock options and restricted stock totaling 130,112 shares and 30,036 shares for the three months ended September 30, 2015 and 2014, respectively, and 170,429 and 87,900 shares for the nine months ended September 30, 2015 and 2014, respectively, were excluded from the computation of diluted earnings per share because their effect would have been antidilutive. The computation of diluted shares can vary among periods due, in part, to the change in the average price of the Company’s common stock.

Credit Facility

Credit Facility	9 Months Ended
	Sep. 30, 2015
Debt Disclosure [Abstract]
Credit Facility	9. Credit Facility In January 2013, the Company entered into a three-year credit agreement (“Credit Agreement”) that provides for revolving loans and letters of credit up to an aggregate of $50.0 million (“Credit Facility”). As of September 30, 2015, there was $49.9 million available to borrow under the Credit Facility. Subject to satisfaction of certain specified conditions, the Company is permitted to upsize the Credit Facility by an additional $50.0 million in total. Borrowings under the Credit Facility will bear interest at a rate per annum equal to either of the following, as designated by the Company for each borrowing: (A) the sum of (i) the greatest of (a) the prime rate, as defined, (b) the federal funds effective rate plus 0.50% and (c) one month adjusted LIBOR plus 1.00% plus (ii) 0.50% or (B) the sum of (i) adjusted LIBOR plus (ii) 1.50%. Default interest is 2.00% per annum in excess of the rate otherwise applicable in the case of any overdue principal or any other overdue amount. The Company is also required to pay a commitment fee to the lenders under the Credit Facility in respect of unutilized revolving loan commitments at a rate of 0.30% per annum. The Company’s existing and future material domestic subsidiaries (other than any broker-dealer subsidiary) have guaranteed the Company’s obligations under the Credit Agreement. Subject to customary exceptions and exclusions, the Credit Facility is collateralized by first priority pledges (subject to permitted liens) of substantially all of the Company’s personal property assets and the personal property assets of the Company’s domestic subsidiaries that have guaranteed the Credit Facility, including the equity interests of the Company’s domestic subsidiaries and the equity interests of certain of the Company’s foreign subsidiaries (limited, in the case of the voting equity interests of the foreign subsidiaries, to a pledge of 65% of those equity interests). The Credit Agreement requires that the Company’s consolidated total leverage ratio tested on the last day of each fiscal quarter not exceed 2.5 to 1.0. The Credit Agreement also requires that the Company’s consolidated interest coverage ratio tested on the last day of each fiscal quarter not fall below 3.5 to 1.0. The Company was in compliance with all applicable covenants at December 31, 2014 and September 30, 2015. If an event of default occurs, including failure to pay principal or interest due on the loan balance, a voluntary or involuntary proceeding seeking liquidation, change in control of the Company, or one or more judgments against the Company in excess of $10 million, the lenders would be entitled to accelerate the facility and take various other actions, including all actions permitted to be taken by a secured creditor. If certain bankruptcy events of default occur, the facility will automatically accelerate.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2015
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	10. Commitments and Contingencies Lease Commitments The Company leases office space under non-cancelable lease agreements expiring at various dates through 2027. Office space leases are subject to escalation based on certain costs incurred by the landlord. Minimum rental commitments as of September 30, 2015 under such operating leases were as follows (in thousands): Remainder of 2015 $ 657 2016 3,424 2017 3,350 2018 3,076 2019 2,899 2020 and thereafter 11,757 $ 25,163 Rental expense was $3.0 million and $2.9 million for the nine months ended September 30, 2015 and 2014, respectively, and is included in occupancy expense in the Consolidated Statements of Operations. Rental expense has been recorded based on the total minimum lease payments after giving effect to rent abatement and concessions, which are being amortized on a straight-line basis over the life of the lease. The Company is contingently obligated for standby letters of credit amounting to $1.3 million that were issued to landlords for office space. The Company has assigned two lease agreements on leased properties to separate third parties. The Company is contingently liable should the assignees default on future lease obligations through the lease termination dates of November 2015 and November 2020. The aggregate amount of future lease obligations under these arrangements is $1.6 million as of September 30, 2015. Legal Matters In the normal course of business, the Company and its subsidiaries included in the consolidated financial statements may be involved in various lawsuits, proceedings and regulatory examinations. The Company assesses its liabilities and contingencies in connection with outstanding legal proceedings, if any, utilizing the latest information available. For matters where it is probable that the Company will incur a material loss and the amount can be reasonably estimated, the Company would establish an accrual for the loss. Once established, the accrual would be adjusted to reflect any relevant developments. When a loss contingency is not both probable and estimable, the Company does not establish an accrual. Based on currently available information, the outcome of the Company’s outstanding matters is not expected to have a material adverse impact on the Company’s financial position. It is not presently possible to determine the ultimate exposure to these matters and there is no assurance that the resolution of the outstanding matters will not significantly exceed any reserves accrued by the Company. Other The Company, through two regulated subsidiaries, executes certain bond transactions between and among institutional investor and broker-dealer clients on a matched principal basis by serving as counterparty to both the buyer and the seller in trades which settle through third-party clearing brokers. Settlement typically occurs within one to three trading days after the trade date. Cash settlement of the transaction occurs upon receipt or delivery of the underlying instrument that was traded. For the nine months ended September 30, 2015 and 2014, revenues from matched principal transactions were $11.6 million and $4.7 million, respectively. Under securities clearing agreements with the third party clearing brokers, the Company maintains a collateral deposit with each clearing broker in the form of cash. As of September 30, 2015, the amount of the collateral deposits included in prepaid expenses and other assets in the Consolidated Statements of Financial Condition was $1.0 million. For the nine months ended September 30, 2015 and 2014, clearing expenses associated with matched principal transactions were $2.3 million and $0.9 million, respectively, and are classified under general and administrative expense on the Consolidated Statements of Operations. In its role as matched principal counterparty, the Company is exposed to the counterparty credit and settlement risk that arises from the risk that the participants that the Company trades with do not fulfill their obligations to the Company due to bankruptcy, lack of liquidity, operational failure, errors or other reasons. Pursuant to the terms of the securities clearing agreements, the clearing broker has the right to charge the Company for losses resulting from a counterparty’s failure to fulfill its contractual obligations. The losses are not capped at a maximum amount and apply to all trades executed through the clearing broker. At September 30, 2015, the Company had not recorded any liabilities with regard to this right. In the normal course of business, the Company enters into contracts that contain a variety of representations, warranties and general indemnifications. The Company’s maximum exposure under these arrangements is unknown, as this would involve future claims that may be made against the Company that have not yet occurred. However, based on experience, the Company expects the risk of loss to be remote.

Customer Concentration

Customer Concentration	9 Months Ended
	Sep. 30, 2015
Risks And Uncertainties [Abstract]
Customer Concentration	11. Customer Concentration During both the nine months ended September 30, 2015 and 2014, no single client accounted for more than 10% of total revenue. One institutional investor client accounted for 15.5% and 14.8% of trading volumes during the nine months ended September 30, 2015 and 2014, respectively.

Share Repurchase Program

Share Repurchase Program	9 Months Ended
	Sep. 30, 2015
Equity [Abstract]
Share Repurchase Program	12. Share Repurchase Program In January 2014, the Board of Directors of the Company authorized a share repurchase program for up to $35.0 million of the Company’s common stock. In July 2014, the Board of Directors increased the authorization under the share repurchase program by an additional $65.0 million of the Company’s common stock. The share repurchase program will expire on December 31, 2015. For the nine months ended September 30, 2015, the Company repurchased 238,201 shares of common stock at a cost of $20.0 million. As of September 30, 2015, approximately $42.0 million remains authorized for repurchase under the program. Shares repurchased under the program will be held in treasury for future use.

Segment and Geographic Informat

Segment and Geographic Information	9 Months Ended
	Sep. 30, 2015
Segment Reporting [Abstract]
Segment and Geographic Information	13. Segment and Geographic Information The Company operates an electronic multi-party platform for the trading of fixed-income securities and provides related data, analytics, compliance tools and post-trade services. The Company considers its operations to constitute a single business segment because of the highly integrated nature of these product and services, of the financial markets in which the Company competes and of the Company’s worldwide business activities. The Company believes that results by geographic region or client sector are not necessarily meaningful in understanding its business. For the three and nine months ended September 30, 2015 and 2014, the U.K. was the only individual foreign country in which the Company had a subsidiary that accounted for 10% or more of the total revenues or total long-lived assets of the Company. Revenues and long-lived assets are attributed to a geographic area based on the location of the particular subsidiary. Long-lived assets are defined as furniture, equipment, leasehold improvements and capitalized software, net of accumulated depreciation and amortization. Information regarding revenue for the three and nine months ended September 30, 2015 and 2014 and long-lived assets as of September 30, 2015 and December 31, 2014 was as follows: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 (In thousands) Revenues United States $ 64,098 $ 54,849 $ 196,488 $ 163,469 United Kingdom 9,830 9,197 29,094 28,556 Other 264 199 872 582 Total $ 74,192 $ 64,245 $ 226,454 $ 192,607 As of September 30, 2015 December 31, 2014 (In thousands) Long-lived assets, as defined United States $ 21,868 $ 23,099 United Kingdom 9,140 9,057 Other 19 29 Total $ 31,027 $ 32,185

Significant Accounting Polici22

Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2015
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The consolidated financial statements include the accounts of the Company and its subsidiaries. All intercompany transactions and balances have been eliminated. These consolidated financial statements are unaudited and should be read in conjunction with the audited consolidated financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014. The consolidated financial information as of December 31, 2014 has been derived from audited financial statements not included herein. These unaudited consolidated financial statements are prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) and the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) with respect to Form 10-Q and reflect all adjustments that, in the opinion of management, are normal and recurring, and that are necessary for a fair statement of the results for the interim periods presented. In accordance with such rules and regulations, certain disclosures that are normally included in annual financial statements have been omitted. Interim period operating results may not be indicative of the operating results for a full year.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents includes cash and money market instruments that are primarily maintained at one major global bank. Given this concentration, the Company is exposed to certain credit risk in relation to its deposits at this bank. The Company defines cash equivalents as short-term interest-bearing investments with maturities at the time of purchase of three months or less.
Securities Available-for-Sale	Securities Available-for-Sale The Company classifies its marketable securities as available-for-sale securities. Unrealized marketable securities gains and losses, net of taxes, are included in accumulated other comprehensive loss in the Consolidated Statements of Financial Condition. Realized gains and losses are recorded in the Consolidated Statements of Operations in other revenues. For the purpose of computing realized gains and losses, cost is determined on a specific identification basis. The Company assesses whether an other-than-temporary impairment loss on the investments has occurred due to declines in fair value or other market conditions. The portion of an other-than-temporary impairment related to credit loss is recorded as a charge in the Consolidated Statements of Operations. The remainder is recognized in accumulated other comprehensive loss if the Company does not intend to sell the security and it is more likely than not that the Company will not be required to sell the security prior to recovery. No charges for other-than-temporary losses were recorded during the nine months ended September 30, 2015 and 2014.
Fair Value Financial Instruments	Fair Value Financial Instruments 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.” A three-tiered hierarchy for determining fair value has been established that prioritizes inputs to valuation techniques used in fair value calculations. The three levels of inputs are defined as Level 1 (unadjusted quoted prices for identical assets or liabilities in active markets), Level 2 (inputs that are observable in the marketplace other than those inputs classified in Level 1) and Level 3 (inputs that are unobservable in the marketplace). The Company’s financial assets and liabilities measured at fair value on a recurring basis consist of its money market funds, securities available-for-sale portfolio and foreign currency forward contracts. All other financial instruments are short-term in nature and the carrying amount is reported in the Consolidated Statements of Financial Condition approximate fair value.
Allowance for Doubtful Accounts	Allowance for Doubtful Accounts All accounts receivable have contractual maturities of less than one year and are derived from trading-related fees and commissions and revenues from products and services. The Company continually monitors collections and payments from its customers and maintains an allowance for doubtful accounts. The allowance for doubtful accounts is based upon the historical collection experience and specific collection issues that have been identified. Additions to the allowance for doubtful accounts are charged to bad debt expense, which is included in general and administrative expense in the Company’s Consolidated Statements of Operations.
Depreciation and Amortization	Depreciation and Amortization Fixed assets are carried at cost less accumulated depreciation. The Company uses the straight-line method of depreciation over three to seven years. The Company amortizes leasehold improvements on a straight-line basis over the lesser of the life of the improvement or the remaining term of the lease.
Software Development Costs	Software Development Costs The Company capitalizes certain costs associated with the development of internal use software, including among other items, employee compensation and related benefits and third party consulting costs at the point at which the conceptual formulation, design and testing of possible software project alternatives have been completed. Once the product is ready for its intended use, such costs are amortized on a straight-line basis over three years. The Company reviews the amounts capitalized for impairment whenever events or changes in circumstances indicate that the carrying amounts of the assets may not be recoverable.
Cash Provided as Collateral	Cash Provided as Collateral Cash is provided as collateral for broker-dealer clearing accounts. Cash provided as collateral is included in prepaid expenses and other assets in the Consolidated Statements of Financial Condition.
Foreign Currency Translation and Forward Contracts	Foreign Currency Translation and Forward Contracts Assets and liabilities denominated in foreign currencies are translated using exchange rates at the end of the period; revenues and expenses are translated at average monthly rates. Gains and losses on foreign currency translation are a component of accumulated other comprehensive loss in the Consolidated Statements of Financial Condition. Transaction gains and losses are recorded in general and administrative expense in the Consolidated Statements of Operations. The Company enters into foreign currency forward contracts to hedge its net investment in its U.K. subsidiaries. Gains and losses on these transactions are included in accumulated other comprehensive loss in the Consolidated Statements of Financial Condition.
Revenue Recognition	Revenue Recognition The majority of the Company’s revenues are derived from commissions for trades executed on its platform and distribution fees that are billed to its broker-dealer clients on a monthly basis. The Company also derives revenues from information and post-trade services, technology products and services, investment income and other income. Commission revenue. Commissions are generally calculated as a percentage of the notional dollar volume of bonds traded on the platform and vary based on the type, size, yield and maturity of the bond traded. Under the Company’s transaction fee plans, bonds that are more actively traded or that have shorter maturities are generally charged lower commissions, while bonds that are less actively traded or that have longer maturities generally command higher commissions. For trades that the Company executes between and among institutional investor and broker-dealer clients on a matched principal basis by serving as counterparty to both the buyer and the seller, the Company earns the commission through the difference in price between the two matched principal trades. Fee programs for certain products include distribution fees which are recognized monthly. Information and post-trade services. The Company generates revenue from information services provided to our broker-dealer clients, institutional investor clients and data-only subscribers. Information services are invoiced monthly, quarterly or annually. When billed in advance, revenues are deferred and recognized monthly on a straight-line basis. The Company also generates revenue from regulatory transaction reporting and trade matching services. Revenue is recognized in the period the services are provided. Technology products and services. The Company generates revenues from professional consulting services, technology software licenses and maintenance and support services (referred to as post-contract technical support or “PCS”). Revenue is generally recognized when persuasive evidence of an arrangement exists, delivery has occurred, the fee is fixed or determinable and collection is considered probable. The Company enters into time and materials professional consulting contracts unrelated to any software product. Revenue for time and materials contracts is recognized as services are performed. The Company generally sells software license subscriptions on a stand-alone basis or software licenses and PCS together as part of multiple-element arrangements. Revenue for software license subscriptions is recognized ratably over the contract period. For arrangements that include multiple elements, generally software licenses and PCS, the Company allocates and defers revenue for the undelivered items based on vendor specific objective evidence (“VSOE”) of the fair value of the undelivered elements and recognizes the difference between the total arrangement fee and the amount deferred for the undelivered items as license revenue. When VSOE does not exist for undelivered items, the entire arrangement fee is recognized ratably over the performance period. For PCS, the term is typically one year and revenue is recognized over the duration of the arrangement on a straight-line basis. Initial set-up fees. The Company enters into agreements with its broker-dealer clients pursuant to which the Company provides access to its platform through a non-exclusive and non-transferable license. Broker-dealer clients may pay an initial set-up fee, which is typically due and payable upon execution of a dealer agreement. The initial set-up fee, if any, varies by agreement. Revenue is recognized over the initial term of the agreement, which is generally two years. Initial set-up fees are reported in other income in the Consolidated Statements of Operations.
Stock-Based Compensation	Stock-Based Compensation The Company measures and recognizes compensation expense for all share-based payment awards based on their estimated fair values measured as of the grant date. These costs are recognized as an expense in the Consolidated Statements of Operations over the requisite service period, which is typically the vesting period, with an offsetting increase to additional paid-in capital.
Income Taxes	Income Taxes Income taxes are accounted for using the asset and liability method. Deferred income taxes reflect the net tax effects of temporary differences between the financial reporting and tax bases of assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when such differences are expected to reverse. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. A valuation allowance is recognized against deferred tax assets if it is more likely than not that such assets will not be realized in future years. The Company recognizes interest and penalties related to unrecognized tax benefits in general and administrative expenses in the Consolidated Statements of Operations.
Business Combinations, Goodwill and Intangible Assets	Business Combinations, Goodwill and Intangible Assets Business combinations are accounted for under the purchase method of accounting. The total cost of an acquisition is allocated to the underlying net assets based on their respective estimated fair values. The excess of the purchase price over the estimated fair values of the net assets acquired is recorded as goodwill. Determining the fair value of certain assets acquired and liabilities assumed is judgmental in nature and often involves the use of significant estimates and assumptions, including assumptions with respect to future cash flows, discount rates, growth rates and asset lives. The Company operates as a single reporting unit. Subsequent to an acquisition, goodwill no longer retains its identification with a particular acquisition, but instead becomes identifiable with the entire reporting unit. As a result, all of the fair value of the Company is available to support the value of goodwill. An impairment review of goodwill is performed on an annual basis, at year-end, or more frequently if circumstances change. Intangible assets with definite lives, including purchased technologies, customer relationships and other intangible assets, are amortized on a straight-line basis over their estimated useful lives, ranging from three to 15 years. Intangible assets are assessed for impairment when events or circumstances indicate the existence of a possible impairment.
Earnings Per Share	Earnings Per Share Basic earnings per share is computed by dividing the net income attributable to common stock by the weighted-average number of shares of common stock outstanding during the period. For purposes of computing diluted earnings per share, the weighted-average shares outstanding of common stock reflects the dilutive effect that could occur if convertible securities or other contracts to issue common stock were converted into or exercised for common stock.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with 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 financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In August 2015, the Financial Accounting Standards Board issued Accounting Standards Update (“ASU”) No. 2015-14, “Revenue from Contracts with Customers”, which will replace most of the existing revenue recognition guidance in GAAP. The core principle of the ASU is that an entity should recognize revenue for the transfer of goods or services equal to the amount that it expects to be entitled to receive for those goods or services. The ASU requires additional disclosure about the nature, amount, timing and uncertainty of revenue and cash flows arising from customer contracts, including significant judgments and changes in judgments. The ASU will be effective for the Company beginning January 1, 2018 and allows for both retrospective and prospective methods of adoption. The Company is in the process of determining the method of adoption and assessing the impact of this ASU on the Company’s Consolidated Financial Statements.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Valuation of Company's Assets and Liabilities Measured at Fair Value	The following table summarizes the valuation of the Company’s assets and liabilities measured at fair value as categorized based on the hierarchy described in Note 2. Level 1 Level 2 Level 3 Total (In thousands) As of September 30, 2015 Money market funds $ 51,175 $ — $ — $ 51,175 Securities available-for-sale Municipal securities — 4,274 — 4,274 Corporate bonds — 91,242 — 91,242 Foreign currency forward position — 186 — 186 Total $ 51,175 $ 95,702 $ — $ 146,877 As of December 31, 2014 Money market funds $ 62,126 $ — $ — $ 62,126 Securities available-for-sale Municipal securities — 11,696 — 11,696 Corporate bonds — 53,167 — 53,167 Foreign currency forward position — 103 — 103 Total $ 62,126 $ 64,966 $ — $ 127,092
Summary of Foreign Currency Forward Contracts	A summary of the Company’s foreign currency forward position is as follows: As of September 30, 2015 December 31, 2014 (In thousands) Notional value $ 42,297 $ 32,089 Fair value of notional 42,111 31,986 Fair value of the asset $ 186 $ 103
Summary of Company's Securities Available-for-Sale	The following is a summary of the Company’s securities available-for-sale: Gross Gross Estimated Amortized unrealized unrealized fair cost gains losses value (In thousands) As of September 30, 2015 Municipal securities $ 4,272 $ 2 $ — $ 4,274 Corporate bonds 91,237 73 (68 ) 91,242 Total securities available-for-sale $ 95,509 $ 75 $ (68 ) $ 95,516 As of December 31, 2014 Municipal securities $ 11,693 $ 5 $ (2 ) $ 11,696 Corporate bonds 53,146 50 (29 ) 53,167 Total securities available-for-sale $ 64,839 $ 55 $ (31 ) $ 64,863
Summary of Contractual Maturities of Securities Available-for-Sale	The following table summarizes the contractual maturities of securities available-for-sale: As of September 30, 2015 December 31, 2014 (In thousands) Less than one year $ 42,107 $ 36,062 Due in 1 - 5 years 53,409 28,801 Total securities available-for-sale $ 95,516 $ 64,863
Fair Values and Unrealized Losses on Securities Available-for-Sale	The following table provides fair values and unrealized losses on securities available-for-sale and by the aging of the securities’ continuous unrealized loss position as of September 30, 2015 and December 31, 2014: Less than Twelve Months Twelve Months or More Total Estimated Gross Estimated Gross Estimated Gross fair unrealized fair unrealized fair unrealized value losses value losses value losses (In thousands) As of September 30, 2015 Municipal securities $ — $ — $ — $ — $ — $ — Corporate bonds 37,085 (68 ) — — 37,085 (68 ) Total $ 37,085 $ (68 ) $ — $ — $ 37,085 $ (68 ) As of December 31, 2014 Municipal securities $ 2,139 $ (2 ) $ — $ — $ 2,139 $ (2 ) Corporate bonds 20,487 (29 ) — — 20,487 (29 ) Total $ 22,626 $ (31 ) $ — $ — $ 22,626 $ (31 )

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2015
Goodwill And Intangible Assets Disclosure [Abstract]
Summary of Company's Intangible Assets	Intangible assets that are subject to amortization, including the related accumulated amortization, are comprised of the following: September 30, 2015 December 31, 2014 Cost Accumulated Amortization Net Carrying Amount Cost Accumulated Amortization Net Carrying Amount (In thousands) Technology $ 5,770 $ (5,076 ) $ 694 $ 5,770 $ (3,826 ) $ 1,944 Customer relationships 5,674 (1,464 ) 4,210 5,682 (1,183 ) 4,499 Non-competition agreements 380 (327 ) 53 380 (232 ) 148 Tradenames 370 (328 ) 42 370 (253 ) 117 Total $ 12,194 $ (7,195 ) $ 4,999 $ 12,202 $ (5,494 ) $ 6,707

Income Taxes (Tables)

Income Taxes (Tables)	9 Months Ended
	Sep. 30, 2015
Income Tax Disclosure [Abstract]
Schedule of Provision for Income Taxes	The provision for income taxes consists of the following: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 (In thousands) Current: Federal $ 11,041 $ 9,280 $ 28,131 $ 22,297 State and local 2,036 1,583 5,234 4,356 Foreign 1,234 227 3,189 520 Total current provision 14,311 11,090 36,554 27,173 Deferred: Federal (1,246 ) (354 ) 2,658 3,979 State and local (209 ) (73 ) 420 512 Foreign (218 ) 101 (264 ) 213 Total deferred provision (1,673 ) (326 ) 2,814 4,704 Provision for income taxes $ 12,638 $ 10,764 $ 39,368 $ 31,877
Summary of Company's Net Deferred Tax Assets	The following is a summary of the Company’s net deferred tax assets: As of September 30, 2015 December 31, 2014 Deferred tax assets and liabilities $ 14,053 $ 12,468 Valuation allowance (7,334 ) (7,428 ) Deferred tax assets, net $ 6,719 $ 5,040

Stock-Based Compensation Plans

Stock-Based Compensation Plans (Tables)	9 Months Ended
	Sep. 30, 2015
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation Expense	Stock-based compensation expense for the nine months ended September 30, 2015 and 2014 was as follows: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 (In thousands) Employees $ 2,958 $ 2,231 $ 8,596 $ 6,503 Non-employee directors 294 298 680 676 Total stock-based compensation $ 3,252 $ 2,529 $ 9,276 $ 7,179

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2015
Earnings Per Share [Abstract]
Computation of Basic and Diluted Earnings Per Common Share	The following table sets forth the computation of basic and diluted earnings per common share: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 (In thousands, except per share amounts) Net income $ 22,715 $ 17,504 $ 71,546 $ 53,170 Basic weighted average shares outstanding 36,681 36,856 36,695 36,997 Dilutive effect of stock options and restricted stock 962 949 941 950 Diluted weighted average shares outstanding 37,643 37,805 37,636 37,947 Basic earnings per share $ 0.62 $ 0.47 $ 1.95 $ 1.44 Diluted earnings per share $ 0.60 $ 0.46 $ 1.90 $ 1.40

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2015
Commitments And Contingencies Disclosure [Abstract]
Summary of Minimum Rental Commitments under Operating Leases	Minimum rental commitments as of September 30, 2015 under such operating leases were as follows (in thousands): Remainder of 2015 $ 657 2016 3,424 2017 3,350 2018 3,076 2019 2,899 2020 and thereafter 11,757 $ 25,163

Segment and Geographic Inform29

Segment and Geographic Information (Tables)	9 Months Ended
	Sep. 30, 2015
Segment Reporting [Abstract]
Summary of Revenue and Long-lived Assets	Information regarding revenue for the three and nine months ended September 30, 2015 and 2014 and long-lived assets as of September 30, 2015 and December 31, 2014 was as follows: Three Months Ended September 30, Nine Months Ended September 30, 2015 2014 2015 2014 (In thousands) Revenues United States $ 64,098 $ 54,849 $ 196,488 $ 163,469 United Kingdom 9,830 9,197 29,094 28,556 Other 264 199 872 582 Total $ 74,192 $ 64,245 $ 226,454 $ 192,607 As of September 30, 2015 December 31, 2014 (In thousands) Long-lived assets, as defined United States $ 21,868 $ 23,099 United Kingdom 9,140 9,057 Other 19 29 Total $ 31,027 $ 32,185

Organization and Principal Bu30

Organization and Principal Business Activity - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2015
Accounting Policies [Abstract]
Date of incorporation	Apr. 11, 2000

Significant Accounting Polici31

Significant Accounting Policies - Additional Information (Detail) - USD ($)	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Significant Accounting Policies [Line Items]
Maximum maturity period for classification of investments as cash equivalents	3 months
Investments other-than-temporary losses	$ 0	$ 0
Contractual maturities accounts receivable	less than one year
Term for post-contract technical support	1 year
Term of agreement for revenue recognition	2 years
Minimum [Member]
Significant Accounting Policies [Line Items]
Estimated useful life of fixed assets	3 years
Minimum [Member] | Business Combinations [Member]
Significant Accounting Policies [Line Items]
Estimated life of intangible assets	3 years
Minimum [Member] | Internally Developed Software [Member]
Significant Accounting Policies [Line Items]
Estimated life of intangible assets	3 years
Maximum [Member]
Significant Accounting Policies [Line Items]
Estimated useful life of fixed assets	7 years
Maximum [Member] | Business Combinations [Member]
Significant Accounting Policies [Line Items]
Estimated life of intangible assets	15 years

Net Capital Requirements - Addi

Net Capital Requirements - Additional Information (Detail) $ in Millions	Sep. 30, 2015USD ($)
Brokers And Dealers [Abstract]
Aggregate net capital and financial resources in excess of required level	$ 102.6
Aggregate net capital and financial resources, minimum capital requirement	$ 9

Fair Value Measurements - Valua

Fair Value Measurements - Valuation of Company's Assets and Liabilities Measured at Fair Value (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Money market funds	$ 51,175	$ 62,126
Securities available-for-sale	95,516	64,863
Assets Fair Value Total	146,877	127,092
Municipal Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities available-for-sale	4,274	11,696
Corporate Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities available-for-sale	91,242	53,167
Foreign Exchange Contract [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Foreign currency forward position	186	103
Level 1 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Money market funds	51,175	62,126
Assets Fair Value Total	51,175	62,126
Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets Fair Value Total	95,702	64,966
Level 2 [Member] | Municipal Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities available-for-sale	4,274	11,696
Level 2 [Member] | Corporate Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities available-for-sale	91,242	53,167
Level 2 [Member] | Foreign Exchange Contract [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Foreign currency forward position	$ 186	$ 103

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Fair Value Disclosures [Abstract]
Hedge derivative expiration period	One-month period
Proceeds from the sales and maturities of securities available-for-sale	$ 25	$ 13.5

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Foreign Currency Forward Contract (Detail) - Foreign Exchange Contract [Member] - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Derivatives Fair Value [Line Items]
Notional value	$ 42,297	$ 32,089
Fair value of notional	42,111	31,986
Fair value of the asset	186	103
Accounts Receivable [Member]
Derivatives Fair Value [Line Items]
Fair value of the asset	$ 186	$ 103

Fair Value Measurements - Sum36

Fair Value Measurements - Summary of Company's Securities Available-for-Sale (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	$ 95,509	$ 64,839
Gross unrealized gains	75	55
Gross unrealized losses	(68)	(31)
Securities available-for-sale	95,516	64,863
Municipal Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	4,272	11,693
Gross unrealized gains	2	5
Gross unrealized losses		(2)
Securities available-for-sale	4,274	11,696
Corporate Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	91,237	53,146
Gross unrealized gains	73	50
Gross unrealized losses	(68)	(29)
Securities available-for-sale	$ 91,242	$ 53,167

Fair Value Measurements - Sum37

Fair Value Measurements - Summary of Contractual Maturities of Securities Available-for-Sale (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Less than one year	$ 42,107	$ 36,062
Due in 1 - 5 years	53,409	28,801
Total securities available-for-sale	$ 95,516	$ 64,863

Fair Value Measurements - Fair

Fair Value Measurements - Fair Values and Unrealized Losses on Securities Available-for-Sale (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Schedule Of Available For Sale Securities [Line Items]
Less than Twelve Months, Estimated fair value	$ 37,085	$ 22,626
Less than Twelve Months, Gross unrealized losses	(68)	(31)
Estimated fair value, Total	37,085	22,626
Gross unrealized losses, Total	(68)	(31)
Municipal Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Less than Twelve Months, Estimated fair value		2,139
Less than Twelve Months, Gross unrealized losses		(2)
Estimated fair value, Total		2,139
Gross unrealized losses, Total		(2)
Corporate Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Less than Twelve Months, Estimated fair value	37,085	20,487
Less than Twelve Months, Gross unrealized losses	(68)	(29)
Estimated fair value, Total	37,085	20,487
Gross unrealized losses, Total	$ (68)	$ (29)

Goodwill and Intangible Asset39

Goodwill and Intangible Assets - Additional Information (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Goodwill [Line Items]
Goodwill and intangible assets with indefinite lives	$ 64,712		$ 66,419
Amortization expense associated with identifiable intangible assets	1,700	$ 1,700
Estimated total amortization expense 2015	2,300
Estimated total amortization expense 2016	700
Estimated total amortization expense 2017	400
Estimated total amortization expense 2018	400
Estimated total amortization expense 2019	400
Indefinite-lived Intangible Assets [Member]
Goodwill [Line Items]
Goodwill and intangible assets with indefinite lives	$ 59,700		$ 59,700

Goodwill and Intangible Asset40

Goodwill and Intangible Assets - Summary of Company's Intangible Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Finite Lived Intangible Assets [Line Items]
Cost	$ 12,194	$ 12,202
Accumulated Amortization	(7,195)	(5,494)
Net Carrying Amount	4,999	6,707
Technology [Member]
Finite Lived Intangible Assets [Line Items]
Cost	5,770	5,770
Accumulated Amortization	(5,076)	(3,826)
Net Carrying Amount	694	1,944
Customer Relationships [Member]
Finite Lived Intangible Assets [Line Items]
Cost	5,674	5,682
Accumulated Amortization	(1,464)	(1,183)
Net Carrying Amount	4,210	4,499
Non-Competition Agreements [Member]
Finite Lived Intangible Assets [Line Items]
Cost	380	380
Accumulated Amortization	(327)	(232)
Net Carrying Amount	53	148
Tradenames - Finite Life [Member]
Finite Lived Intangible Assets [Line Items]
Cost	370	370
Accumulated Amortization	(328)	(253)
Net Carrying Amount	$ 42	$ 117

Income Taxes - Schedule of Prov

Income Taxes - Schedule of Provision for Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Current:
Federal	$ 11,041	$ 9,280	$ 28,131	$ 22,297
State and local	2,036	1,583	5,234	4,356
Foreign	1,234	227	3,189	520
Total current provision	14,311	11,090	36,554	27,173
Deferred:
Federal	(1,246)	(354)	2,658	3,979
State and local	(209)	(73)	420	512
Foreign	(218)	101	(264)	213
Total deferred provision	(1,673)	(326)	2,814	4,704
Provision for income taxes	$ 12,638	$ 10,764	$ 39,368	$ 31,877

Income Taxes - Summary of Compa

Income Taxes - Summary of Company's Net Deferred Tax Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Deferred tax assets and liabilities	$ 14,053	$ 12,468
Valuation allowance	(7,334)	(7,428)
Deferred tax assets, net	$ 6,719	$ 5,040

Stock-Based Compensation Plan43

Stock-Based Compensation Plans - Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	$ 3,252	$ 2,529	$ 9,276	$ 7,179
Employees [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	2,958	2,231	8,596	6,503
Non-Employee Directors [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	$ 294	$ 298	$ 680	$ 676

Stock-Based Compensation Plan44

Stock-Based Compensation Plans - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	9 Months Ended
	Jan. 31, 2015	Sep. 30, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average period over which cost is expected to be recognized		2 years 3 months 18 days
Unrecognized compensation costs related to non-vested		$ 20.7
Chief Executive Officer [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Aggregate grant date fair value	$ 8
Chief Executive Officer [Member] | Incentive Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of non-option equity instruments granted during the period	119,981
Exercise price for the shares of the Company's common stock	$ 88.25
Percentage of fair market value of the common stock on the grant date	125.00%
Chief Executive Officer [Member] | Performance Based Share [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of non-option equity instruments granted during the period	116,659
Chief Executive Officer [Member] | Share-based Compensation Award, Tranche One [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award award vesting date		Jan. 15, 2018
Chief Executive Officer [Member] | Share-based Compensation Award, Tranche One [Member] | January 15, 2018 [Member] | Incentive Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting rights		33.33%
Chief Executive Officer [Member] | Share-based Compensation Award, Tranche Two [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award award vesting date		Jan. 15, 2019
Chief Executive Officer [Member] | Share-based Compensation Award, Tranche Two [Member] | January 15, 2019 [Member] | Incentive Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting rights		33.33%
Chief Executive Officer [Member] | Share-based Compensation Award, Tranche Three [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award award vesting date		Jan. 15, 2020
Chief Executive Officer [Member] | Share-based Compensation Award, Tranche Three [Member] | January 15, 2020 [Member] | Incentive Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting rights		33.33%
Employees [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Aggregate grant date fair value		$ 8.3
Employees [Member] | Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average period over which cost is expected to be recognized		3 years
Employees [Member] | Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average period over which cost is expected to be recognized		5 years
Employees [Member] | Performance Based Share [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of non-option equity instruments granted during the period		28,520
Exercise price for the shares of the Company's common stock		$ 36.46
Number of options to purchase shares of common stock		669
Weighted-average grant date fair value per share		$ 70.60
Employees [Member] | Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of non-option equity instruments granted during the period		111,089
Weighted-average grant date fair value per share		$ 74.44
Minimum Performance Level [Member] | Chief Executive Officer [Member] | January 15, 2020 [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting rights	100.00%
Above the Minimum Performance Level [Member] | Chief Executive Officer [Member] | Performance Based Share [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, nonvested, number		70,927
Above the Minimum Performance Level [Member] | Chief Executive Officer [Member] | January 15, 2019 [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting rights	50.00%
Above the Minimum Performance Level [Member] | Chief Executive Officer [Member] | January 15, 2020 [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting rights	50.00%
Above the Minimum Performance Level [Member] | Chief Executive Officer [Member] | Share-based Compensation Award, Tranche One [Member] | January 15, 2019 [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting rights	50.00%
Above the Minimum Performance Level [Member] | Chief Executive Officer [Member] | Share-based Compensation Award, Tranche Two [Member] | January 15, 2020 [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting rights	50.00%

Earnings Per Share - Computatio

Earnings Per Share - Computation of Basic and Diluted Earnings Per Common Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Earnings Per Share Basic And Diluted [Abstract]
Net income	$ 22,715	$ 17,504	$ 71,546	$ 53,170
Basic weighted average shares outstanding	36,681	36,856	36,695	36,997
Dilutive effect of stock options and restricted stock	962	949	941	950
Diluted weighted average shares outstanding	37,643	37,805	37,636	37,947
Basic earnings per share	$ 0.62	$ 0.47	$ 1.95	$ 1.44
Diluted earnings per share	$ 0.60	$ 0.46	$ 1.90	$ 1.40

Earnings Per Share - Additional

Earnings Per Share - Additional Information (Detail) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Stock Options and Restricted Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Stock options and restricted stock excluded from the computation of diluted earnings per share	130,112	30,036	170,429	87,900

Credit Facility - Additional In

Credit Facility - Additional Information (Detail) - USD ($)	1 Months Ended	9 Months Ended
	Jan. 31, 2013	Sep. 30, 2015
Line Of Credit Facility [Line Items]
Revolving loans and letters of credit	$ 50,000,000
Additional Credit Facility	$ 50,000,000
Amount available under credit facility		$ 49,900,000
Period of credit agreement	3 years
LIBOR rate description		the federal funds effective rate plus 0.50% and (c) one month adjusted LIBOR plus 1.00% plus (ii) 0.50% or (B) the sum of (i) adjusted LIBOR plus (ii) 1.50%
Federal funds effective rate		0.50%
One month adjusted LIBOR		1.00%
LIBOR Rate		0.50%
Adjusted LIBOR rate		1.50%
Interest per annum		2.00%
Revolving loan commitment rate		0.30%
Equity interest		65.00%
Maximum [Member]
Line Of Credit Facility [Line Items]
Total leverage ratio		250.00%
Minimum [Member]
Line Of Credit Facility [Line Items]
Interest coverage ratio		350.00%
Excess judgments against the company		$ 10,000,000

Commitments and Contingencies -

Commitments and Contingencies - Summary of Minimum Rental Commitments under Operating Leases (Detail) $ in Thousands	Sep. 30, 2015USD ($)
Operating Leases Future Minimum Payments Due [Abstract]
Remainder of 2015	$ 657
2,016	3,424
2,017	3,350
2,018	3,076
2,019	2,899
2020 and thereafter	11,757
Operating Leases	$ 25,163

Commitments and Contingencies49

Commitments and Contingencies - Additional Information (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2015USD ($)AgreementSubsidiary	Sep. 30, 2014USD ($)
Loss Contingencies [Line Items]
Rental expense	$ 3	$ 2.9
Number of lease agreements assigned to third parties | Agreement	2
Lease termination dates	November 2015 and November 2020
Future lease obligations under sublease arrangements	$ 1.6
Number of subsidiaries | Subsidiary	2
Settlement days of bond transaction	Within one to three trading days
Revenues from riskless principal transactions	$ 11.6	4.7
Collateral deposit	1
General and Administrative Expense [Member]
Loss Contingencies [Line Items]
Clearing expenses	2.3	$ 0.9
Standby Letters of Credit [Member]
Loss Contingencies [Line Items]
Contingent obligation for standby letter of credit issued to Landlord	$ 1.3

Customer Concentration - Additi

Customer Concentration - Additional Information (Detail) - Customer	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Concentration Risk [Line Items]
Number of client accounted for total revenue	0	0
Customer Concentration Risk | Trading Volume
Concentration Risk [Line Items]
One institutional investor client	15.50%	14.80%

Share Repurchase Program - Addi

Share Repurchase Program - Additional Information (Detail) - USD ($)	9 Months Ended
	Sep. 30, 2015	Jul. 31, 2014	Jan. 31, 2014
Equity [Abstract]
Shares repurchase program authorized		$ 65,000,000	$ 35,000,000
Common stock shares repurchased	238,201
Cost of common stock shares repurchased	$ 20,000,000
Shares repurchase program expiration date	Dec. 31, 2015
Dollar value of shares that may yet be purchased under share repurchase program	$ 42,000,000

Segment and Geographic Inform52

Segment and Geographic Information - Additional Information (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Geographic Concentration Risk [Member] | Total Revenue and Long-lived Assets [Member] | United Kingdom [Member]
Revenues From External Customers And Long Lived Assets [Line Items]
Concentration Risk, Percentage	10.00%	10.00%	10.00%	10.00%

Segment and Geographic Inform53

Segment and Geographic Information - Summary of Revenue and Long-lived Assets (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
Segment Reporting Information [Line Items]
Revenues	$ 74,192	$ 64,245	$ 226,454	$ 192,607
Long-lived assets	31,027		31,027		$ 32,185
United States [Member]
Segment Reporting Information [Line Items]
Revenues	64,098	54,849	196,488	163,469
Long-lived assets	21,868		21,868		23,099
United Kingdom [Member]
Segment Reporting Information [Line Items]
Revenues	9,830	9,197	29,094	28,556
Long-lived assets	9,140		9,140		9,057
Other [Member]
Segment Reporting Information [Line Items]
Revenues	264	$ 199	872	$ 582
Long-lived assets	$ 19		$ 19		$ 29