Piper Sandler Companies (PIPR) 10-Q 30 Jul 14 2014 Q2 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	6 Months Ended
	Jun. 30, 2014	Jul. 18, 2014
Document and Entity Information [Abstract]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	30-Jun-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q2	'
Trading Symbol	'PJC	'
Entity Registrant Name	'Piper Jaffray Companies	'
Entity Central Index Key	'0001230245	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	16,257,151

Consolidated_Statements_of_Fin

Consolidated Statements of Financial Condition (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Assets	'	'
Cash and cash equivalents	$55,221	$123,683
Cash and cash equivalents segregated for regulatory purposes	44,020	43,012
Receivables:	'	'
Customers	64,836	11,633
Brokers, dealers and clearing organizations	158,490	127,113
Securities purchased under agreements to resell	156,323	167,875
Financial instruments and other inventory positions owned	569,696	406,513
Financial instruments and other inventory positions owned and pledged as collateral	899,375	957,515
Total financial instruments and other inventory positions owned	1,469,071	1,364,028
Fixed assets (net of accumulated depreciation and amortization of $62,828 and $62,311, respectively)	15,651	16,114
Goodwill	211,878	210,634
Intangible assets (net of accumulated amortization of $36,505 and $31,869, respectively)	35,294	39,930
Investments	116,389	112,043
Other assets	98,352	102,092
Total assets	2,425,525	2,318,157
Liabilities and Shareholders’ Equity	'	'
Short-term financing	362,401	514,711
Variable rate senior notes	125,000	125,000
Payables:	'	'
Customers	45,499	33,109
Brokers, dealers and clearing organizations	240,538	27,722
Securities sold under agreements to repurchase	11,815	4,397
Financial instruments and other inventory positions sold, but not yet purchased	518,286	512,833
Accrued compensation	134,915	159,928
Other liabilities and accrued expenses	57,314	58,385
Total liabilities	1,495,768	1,436,085
Shareholders’ equity:	'	'
Common stock, $0.01 par value: Shares authorized: 100,000,000 at June 30, 2014 and December 31, 2013; Shares issued: 19,523,371 at June 30, 2014 and 19,537,127 at December 31, 2013; Shares outstanding: 14,994,764 at June 30, 2014 and 14,383,418 at December 31, 2013	195	195
Additional paid-in capital	738,106	740,321
Retained earnings	199,854	163,893
Less common stock held in treasury, at cost: 4,528,607 shares at June 30, 2014 and 5,153,709 shares at December 31, 2013	-151,459	-170,629
Accumulated other comprehensive income	1,152	896
Total common shareholders’ equity	787,848	734,676
Noncontrolling interests	141,909	147,396
Total shareholders’ equity	929,757	882,072
Total liabilities and shareholders’ equity	$2,425,525	$2,318,157

Consolidated_Statements_of_Fin1

Consolidated Statements of Financial Condition (Parenthetical) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, except Share data, unless otherwise specified
Statement of Financial Position [Abstract]	'	'
Accumulated depreciation and amortization on fixed assets	$62,828	$62,311
Accumulated amortization on intangible assets	$36,505	$31,869
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	19,523,371	19,537,127
Common stock, shares outstanding	14,994,764	14,383,418
Common stock held in treasury, shares	4,528,607	5,153,709

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	3 Months Ended		6 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Revenues:	'	'	'	'
Investment banking	$103,813	$53,255	$192,287	$94,076
Institutional brokerage	34,528	24,611	78,562	64,758
Asset management	22,266	18,427	43,225	36,883
Interest	12,448	12,286	26,107	23,109
Investment income/(loss)	2,921	-2,059	9,689	3,006
Total revenues	175,976	106,520	349,870	221,832
Interest expense	5,945	6,748	11,706	12,527
Net revenues	170,031	99,772	338,164	209,305
Non-interest expenses:	'	'	'	'
Compensation and benefits	103,076	65,000	203,565	131,105
Occupancy and equipment	7,061	6,543	13,839	12,360
Communications	5,432	5,030	11,387	10,262
Floor brokerage and clearance	1,788	2,247	3,622	4,397
Marketing and business development	6,709	5,957	12,960	10,937
Outside services	9,914	8,449	18,682	15,663
Intangible asset amortization expense	2,318	1,661	4,636	3,322
Other operating expenses	3,316	1,552	6,343	-242
Total non-interest expenses	139,614	96,439	275,034	187,804
Income from continuing operations before income tax expense	30,417	3,333	63,130	21,501
Income tax expense	10,049	1,644	19,876	7,244
Income from continuing operations	20,368	1,689	43,254	14,257
Discontinued operations:	'	'	'	'
Loss from discontinued operations, net of tax	0	-1,871	0	-2,392
Net income/(loss)	20,368	-182	43,254	11,865
Net income/(loss) applicable to noncontrolling interests	2,155	-2,670	7,293	-769
Net income applicable to Piper Jaffray Companies	18,213	2,488	35,961	12,634
Net income/(loss) applicable to Piper Jaffray Companies’ common shareholders	16,717	2,266	32,806	11,333
Amounts applicable to Piper Jaffray Companies	'	'	'	'
Net income/(loss) from continuing operations	18,213	4,359	35,961	15,026
Net loss from discontinued operations	$0	($1,871)	$0	($2,392)
Earnings/(loss) per basic common share	'	'	'	'
Income from continuing operations	$1.12	$0.25	$2.22	$0.86
Loss from discontinued operations	$0	($0.11)	$0	($0.14)
Earnings per basic common share	$1.12	$0.15	$2.22	$0.73
Earnings/(loss) per diluted common share	'	'	'	'
Income from continuing operations	$1.11	$0.25	$2.21	$0.86
Loss from discontinued operations	$0	($0.11)	$0	($0.14)
Earnings per diluted common share	$1.11	$0.15	$2.21	$0.73
Weighted average number of common shares outstanding	'	'	'	'
Basic	14,958	15,621	14,786	15,602
Diluted	15,013	15,626	14,836	15,619

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Statement of Comprehensive Income [Abstract]	'	'	'	'
Net income/(loss)	$20,368	($182)	$43,254	$11,865
Other comprehensive income/(loss), net of tax:	'	'	'	'
Foreign currency translation adjustment	205	27	256	-121
Comprehensive income/(loss)	20,573	-155	43,510	11,744
Comprehensive income/(loss) applicable to noncontrolling interests	2,155	-2,670	7,293	-769
Comprehensive income applicable to Piper Jaffray Companies	$18,418	$2,515	$36,217	$12,513

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013
Operating Activities:	'	'
Net income/(loss)	$43,254	$11,865
Adjustments to reconcile net income/(loss) to net cash provided by/(used in) operating activities:	'	'
Depreciation and amortization of fixed assets	2,748	2,852
Deferred income taxes	3,698	11,571
Loss on sale of FAMCO	0	-1,876
Share-based and deferred compensation	13,889	4,890
Amortization of intangible assets	4,636	3,322
Amortization of forgivable loans	2,614	3,226
Decrease/(increase) in operating assets:	'	'
Cash and cash equivalents segregated for regulatory purposes	-1,008	3,990
Receivables:	'	'
Customers	-53,203	-6,560
Brokers, dealers and clearing organizations	-31,377	25,680
Securities purchased under agreements to resell	11,552	-2,639
Net financial instruments and other inventory positions owned	-99,590	-145,019
Investments	-4,346	-19,936
Other assets	-3,605	-6,749
Payables:	'	'
Customers	12,390	-9,321
Brokers, dealers and clearing organizations	212,816	69,324
Securities sold under agreements to repurchase	7,418	0
Accrued compensation	-14,722	-53,781
Other liabilities and accrued expenses	-1,085	-17,876
Decrease in assets held for sale	0	605
Decrease in liabilities held for sale	0	-465
Net cash provided by/(used in) operating activities	106,079	-123,145
Investing Activities:	'	'
Sale of FAMCO	0	250
Purchases of fixed assets, net	-2,250	-1,092
Net cash used in investing activities	-2,250	-842
Financing Activities:	'	'
Increase/(decrease) in short-term financing	-152,310	65,794
Proceeds from Issuance of Senior Long-term Debt	50,000	0
Repayments of Long-term Debt	-50,000	0
Decrease in securities sold under agreements to repurchase	0	-19,239
Increase/(decrease) in noncontrolling interests	-12,780	81,868
Repurchase of common stock	-8,806	-40,496
Excess tax benefit from share-based compensation	262	46
Proceeds from stock option transactions	1,322	0
Net cash provided by/(used in) financing activities	-172,312	87,973
Currency adjustment:	'	'
Effect of exchange rate changes on cash	21	-83
Net decrease in cash and cash equivalents	-68,462	-36,097
Cash and cash equivalents at beginning of year	123,683	105,371
Cash and cash equivalents at end of year	55,221	69,274
Supplemental disclosure of cash flow information –	'	'
Interest	11,749	11,113
Income taxes	22,573	671
Non-cash financing activities –	'	'
Issuance of common stock for retirement plan obligations: 103,598 shares and 96,049 shares for the six months ended June 30, 2014 and 2013, respectively	4,156	3,939
Issuance of restricted common stock for annual equity award: 402,074 shares and 431,582 shares for the six months ended June 30, 2014 and 2013, respectively	$16,131	$17,699

Consolidated_Statements_of_Cas1

Consolidated Statements of Cash Flows (Parenthetical)	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Statement of Cash Flows [Abstract]	'	'
Number of common stock issued for retirement plan obligations	103,598	96,049
Number of restricted common stock issued for annual equity award	402,074	431,582

Organization_and_Basis_of_Pres

Organization and Basis of Presentation	6 Months Ended
	Jun. 30, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Organization and Basis of Presentation	'
	Organization and Basis of Presentation
	Organization
	Piper Jaffray Companies is the parent company of Piper Jaffray & Co. ("Piper Jaffray"), a securities broker dealer and investment banking firm; Piper Jaffray Ltd., a firm providing securities brokerage and mergers and acquisitions services in Europe headquartered in London, England; Advisory Research, Inc. ("ARI"), which provides asset management services to separately managed accounts, closed-end and open-end funds and partnerships; Piper Jaffray Investment Group Inc., which consists of entities providing alternative asset management services; Piper Jaffray Financial Products Inc., Piper Jaffray Financial Products II Inc. and Piper Jaffray Financial Products III Inc., entities that facilitate derivative transactions; and other immaterial subsidiaries. Piper Jaffray Companies and its subsidiaries (collectively, the "Company") operate in two reporting segments: Capital Markets and Asset Management. A summary of the activities of each of the Company’s business segments is as follows:
	Capital Markets
	The Capital Markets segment provides institutional sales, trading and research services and investment banking services. Institutional sales, trading and research services focus on the trading of equity and fixed income products with institutions, government and non-profit entities. Revenues are generated through commissions and sales credits earned on equity and fixed income institutional sales activities, net interest revenues on trading securities held in inventory, and profits and losses from trading these securities. Investment banking services include management of and participation in underwritings, merger and acquisition services and public finance activities. Revenues are generated through the receipt of advisory and financing fees. Also, the Company generates revenue through strategic trading and investing activities, which focus on proprietary investments in municipal bonds, mortgage-backed securities, equity securities, and merchant banking activities involving equity or debt investments in late stage private companies. As certain of these efforts have matured and an investment process has been developed, the Company has created alternative asset management funds in merchant banking and municipal securities in order to invest firm capital as well as to seek capital from outside investors. The Company receives management and performance fees for managing these funds.
	As discussed in Note 5, the Company discontinued its Hong Kong capital markets business in 2012.
	Asset Management
	The Asset Management segment provides traditional asset management services with product offerings in equity securities and master limited partnerships to institutions and individuals. Revenues are generated in the form of management and performance fees. Revenues are also generated through investments in the partnerships and funds that the Company manages.
	As discussed in Note 5, Fiduciary Asset Management, LLC ("FAMCO") was sold in 2013.
	Basis of Presentation
	The accompanying consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles ("U.S. GAAP") and include the accounts of Piper Jaffray Companies, its wholly owned subsidiaries, and all other entities in which the Company has a controlling financial interest. Noncontrolling interests represent equity interests in consolidated entities that are not attributable, either directly or indirectly, to Piper Jaffray Companies. Noncontrolling interests include the minority equity holders’ proportionate share of the equity in a municipal bond fund, merchant banking fund and private equity investment vehicles. All material intercompany balances have been eliminated.
	The preparation of financial statements and related disclosures in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Although these estimates and assumptions are based on the best information available, actual results could differ from those estimates.
	Reclassifications
	In 2013, the Company reclassified interest revenue and expense associated with its derivative contracts to investment banking or institutional brokerage revenues within the consolidated statements of operations to more accurately reflect the nature and intent of the derivative instrument. The Company reclassified $2.1 million and $4.6 million of interest revenue and $2.6 million and $5.4 million of interest expense for the three months and six months ended June 30, 2013, respectively. This change had no effect on net revenues, net income, shareholders’ equity or cash flows for the periods presented.

Summary_of_Significant_Account

Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2014
Accounting Policies [Abstract]	'
Summary of Significant Accounting Policies	'
	Summary of Significant Accounting Policies
	Refer to the Company's Annual Report on Form 10-K for the year ended December 31, 2013 for a full description of the Company's significant accounting policies.

Recent_Accounting_Pronouncemen

Recent Accounting Pronouncements	6 Months Ended
	Jun. 30, 2014
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]	'
Recent Accounting Pronouncements	'
	Recent Accounting Pronouncements
	Adoption of New Accounting Standards
	Investment Companies
	In June 2013, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2013-08, "Financial Services - Investment Companies (Topic 946): Amendments to the Scope, Measurement, and Disclosure Requirements," ("ASU 2013-08") amending FASB Accounting Standards Codification Topic 946, "Financial Services - Investment Companies" ("ASC 946"). The amended guidance changes the approach to the investment company assessment in ASC 946, clarifies the characteristics of an investment company and requires new disclosures for investment company financial statements. ASU 2013-08 was effective for the Company as of January 1, 2014. The adoption of ASU 2013-08 did not impact the Company's results of operations, financial position or disclosures.
	Future Adoption of New Accounting Standards
	Discontinued Operations
	In April 2014, the FASB issued ASU No. 2014-08, "Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360): Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity," ("ASU 2014-08") amending FASB Accounting Standards Codification Topic 205-20, "Discontinued Operations," ("ASC 205-20"). The amended guidance changes the criteria for reporting discontinued operations and requires new disclosures. ASU 2014-08 is effective for annual and interim periods beginning on or after December 15, 2014, and will be applied prospectively.
	Revenue Recognition
	In May 2014, the FASB issued ASU No. 2014-09, "Revenue from Contracts with Customers (Topic 606)," ("ASU 2014-09") which supersedes current revenue recognition guidance, including most industry-specific guidance. ASU 2014-09 requires a company to recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods and services. The guidance also requires additional disclosures regarding the nature, amount, timing and uncertainty of revenue that is recognized. ASU 2014-09 is effective for annual and interim periods beginning after December 15, 2016. Early adoption is not permitted. The Company is evaluating the impact of the new guidance on its consolidated financial statements.
	Repurchase Agreements
	In June 2014, the FASB issued ASU No. 2014-11, "Transfers and Servicing (Topic 860): Repurchase-to-Maturity Transactions, Repurchase Financings, and Disclosures," ("ASU 2014-11") amending FASB Accounting Standards Codification Topic 860, "Transfers and Servicing." The amended guidance changes the accounting for repurchase-to-maturity transactions and repurchase financing arrangements. The guidance also requires new disclosures for certain transfers accounted for as sales and collateral supporting transactions that are accounted for as secured borrowings. ASU 2014-11 is effective for annual and interim periods beginning after December 15, 2014, except for the disclosures related to secured borrowings, which are effective for annual periods beginning after December 15, 2014, and for interim periods beginning after March 15, 2015. The adoption of ASU 2014-11 is not expected to have a material impact on the Company's results of operations or financial position, but may impact the Company's disclosures.

Acquisitions

Acquisitions	6 Months Ended
	Jun. 30, 2014
Business Combinations [Abstract]	'
Acquisitions	'
	Acquisitions
	On July 12, 2013, the Company completed the purchase of Seattle-Northwest Securities Corporation ("Seattle-Northwest"), a Seattle-based investment bank and broker dealer focused on public finance in the Northwest region of the U.S. The purchase was completed pursuant to the Agreement and Plan of Merger dated April 16, 2013. The acquisition of Seattle-Northwest supports the Company's strategy to grow its public finance business.
	On July 16, 2013, the Company completed the purchase of Edgeview Partners, L.P. ("Edgeview"), a middle-market advisory firm specializing in mergers and acquisitions. The purchase was completed pursuant to the Unit Purchase Agreement dated June 17, 2013. The acquisition of Edgeview further strengthened the Company's mergers and acquisitions position in the middle market and added resources dedicated to the private equity community.
	The Company paid $32.7 million in cash for Seattle-Northwest and Edgeview, which represented the fair values as of the respective acquisition dates. The Company also entered into acquisition-related compensation arrangements of $14.3 million which consisted of cash, restricted stock and restricted mutual fund shares ("MFRS Awards") of registered funds managed by the Company's asset management business. Compensation expense related to these arrangements will be amortized on a straight-line basis over the requisite service period of two to five years (a weighted average service period of 4.3 years).
	These acquisitions were accounted for pursuant to FASB Accounting Standards Codification Topic 805, "Business Combinations." Accordingly, the purchase price of each acquisition was allocated to the acquired assets and liabilities assumed based on their estimated fair values as of the respective acquisition dates. The excess of the purchase price over the net assets acquired was allocated between goodwill and intangible assets within the Capital Markets segment. The Company recorded $15.0 million of goodwill on the consolidated statements of financial condition, of which $9.1 million is expected to be deductible for income tax purposes. In management's opinion, the goodwill represents the reputation and expertise of Seattle-Northwest and Edgeview in their respective business lines.
	Identifiable intangible assets purchased by the Company consisted of customer relationships and non-competition agreements with acquisition-date fair values estimated to be $6.0 million and $0.7 million, respectively.
	In the second quarter of 2014, the Company recorded a $1.2 million measurement period adjustment to increase goodwill and acquisition-related deferred tax liabilities. The following table summarizes the estimated fair values of assets acquired and liabilities assumed at the respective dates of acquisition:
	(Dollars in thousands)
	Assets
	Cash and cash equivalents		$	8,014
	Financial instruments and other inventory positions owned		24,074
	Fixed assets		1,247
	Goodwill		15,034
	Intangible assets		6,665
	Other assets		7,678
	Total assets acquired		62,712
	Liabilities
	Payables		1,126
	Financial instruments and other inventory positions sold, but not yet purchased		22,588
	Accrued compensation		1,469
	Other liabilities and accrued expenses		4,789
	Total liabilities assumed		29,972
	Net assets acquired		$	32,740
	Seattle-Northwest and Edgeview results of operations have been included in the Company's consolidated financial statements prospectively from their respective dates of acquisition. These acquisitions have been fully integrated with the Company's existing operations. Accordingly, post-acquisition revenues and net income are not discernible. The following unaudited pro forma financial data assumes the acquisitions had occurred on January 1, 2012, the beginning of the prior annual period in which the acquisitions occurred. Pro forma results have been prepared by adjusting the Company's historical results from continuing operations to include Seattle-Northwest and Edgeview results of operations adjusted for the following changes: depreciation and amortization expenses were adjusted to account for acquisition-date fair value adjustments of fixed assets and intangible assets; compensation and benefits expenses were adjusted to reflect excess partner distributions as compensation expense; and the income tax effect of applying the Company's statutory tax rates to Seattle-Northwest and Edgeview results of operations. The consolidated Company's unaudited pro forma information presented does not necessarily reflect the results of operations that would have resulted had the acquisitions been completed at the beginning of the applicable period presented, does not contemplate anticipated operational efficiencies of the combined entities, nor does it indicate the results of operations in future periods.
		Three Months Ended			Six Months Ended
	(Dollars in thousands)	June 30, 2013			June 30, 2013
	Net revenues	$	107,415		$	220,955
	Net income from continuing operations applicable to Piper Jaffray Companies	$	4,260		$	13,356

Discontinued_Operations

Discontinued Operations	6 Months Ended
	Jun. 30, 2014
Discontinued Operations and Disposal Groups [Abstract]	'
Discontinued Operations	'
	Discontinued Operations
	The Company's Hong Kong capital markets business ceased operations in 2012. In the second quarter of 2013, the Company completed the sale of FAMCO, an asset management subsidiary, for consideration of $4.0 million which consisted of $0.3 million in cash and a $3.7 million note receivable from the buyer. In accordance with the provisions of ASC 205-20, the results from these businesses have been classified as discontinued operations for all periods presented. The Company recorded a $1.9 million net loss and a $2.4 million net loss from discontinued operations for the three months and six months ended June 30, 2013, respectively.
	As part of the FAMCO sale, the Company indemnified the buyer against certain costs and obligations. As of June 30, 2014, a $0.4 million remaining indemnification obligation was included within other liabilities and accrued expenses on the consolidated statements of financial condition. The potential amount of future payments that the Company could be required to make pursuant to the terms of the definitive sale agreement is not limited, however it is not expected to be material.

Financial_Instruments_and_Othe

Financial Instruments and Other Inventory Positions Owned and Financial Instruments and Other Inventory Positions Sold, but Not Yet Purchased	6 Months Ended
	Jun. 30, 2014
Disclosure Financial Instruments And Other Inventory Positions Owned And Financial Instruments And Other Inventory Positions Sold But Not Yet Purchased [Abstract]	'
Financial Instruments and Other Inventory Positions Owned and Financial Instruments and Other Inventory Positions Sold, but Not Yet Purchased	'
	Financial Instruments and Other Inventory Positions Owned and Financial Instruments and Other Inventory Positions Sold, but Not Yet Purchased
	Financial instruments and other inventory positions owned and financial instruments and other inventory positions sold, but not yet purchased were as follows:
		June 30,				December 31,
	(Dollars in thousands)	2014				2013
	Financial instruments and other inventory positions owned:
	Corporate securities:
	Equity securities	$	55,975			$	54,097
	Convertible securities	94,496				80,784
	Fixed income securities	27,344				10,102
	Municipal securities:
	Taxable securities	237,126				232,379
	Tax-exempt securities	467,537				460,865
	Short-term securities	152,209				62,620
	Asset-backed securities	133,719				119,811
	U.S. government agency securities	245,365				304,737
	U.S. government securities	8,185				—
	Derivative contracts	47,115				38,633
	Total financial instruments and other inventory positions owned	1,469,071				1,364,028
	Less noncontrolling interests (1)	(251,519		)		(291,513		)
		$	1,217,552			$	1,072,515
	Financial instruments and other inventory positions sold, but not yet purchased:
	Corporate securities:
	Equity securities	$	96,962			$	69,205
	Fixed income securities	9,974				24,021
	U.S. government agency securities	49,009				120,084
	U.S. government securities	345,756				291,320
	Derivative contracts	16,585				8,203
	Total financial instruments and other inventory positions sold, but not yet purchased	518,286				512,833
	Less noncontrolling interests (2)	(87,087		)		(68,356		)
		$	431,199			$	444,477
	-1	Noncontrolling interests attributable to third party ownership in a consolidated municipal bond fund consist of $109.7 million and $101.8 million of taxable municipal securities, $137.1 million and $183.9 million of tax-exempt municipal securities, and $4.8 million and $5.8 million of derivative contracts as of June 30, 2014 and December 31, 2013, respectively.
	-2	Noncontrolling interests attributable to third party ownership in a consolidated municipal bond fund consist of $85.5 million and $67.4 million of U.S. government securities, and $1.6 million and $1.0 million of derivative contracts as of June 30, 2014 and December 31, 2013, respectively.
	At June 30, 2014 and December 31, 2013, financial instruments and other inventory positions owned in the amount of $899.4 million and $957.5 million, respectively, had been pledged as collateral for short-term financings and repurchase agreements.
	Financial instruments and other inventory positions sold, but not yet purchased represent obligations of the Company to deliver the specified security at the contracted price, thereby creating a liability to purchase the security in the market at prevailing prices. The Company is obligated to acquire the securities sold short at prevailing market prices, which may exceed the amount reflected on the consolidated statements of financial condition. The Company economically hedges changes in the market value of its financial instruments and other inventory positions owned using inventory positions sold, but not yet purchased, interest rate derivatives, credit default swap index contracts, futures and exchange traded options.
	Derivative Contract Financial Instruments
	The Company uses interest rate swaps, interest rate locks, credit default swap index contracts and option contracts to facilitate customer transactions and as a means to manage risk in certain inventory positions. The following describes the Company’s derivatives by the type of transaction or security the instruments are economically hedging.
	Customer matched-book derivatives: The Company enters into interest rate derivative contracts in a principal capacity as a dealer to satisfy the financial needs of its customers.  The Company simultaneously enters into  an interest rate  derivative  contract with a third party for the same notional amount to hedge the interest rate and credit risk of the initial client interest rate derivative contract. In certain limited instances, the Company has only hedged interest rate risk with a third party, and retains uncollateralized credit risk as described below. The instruments use interest rates based upon either the London Interbank Offer Rate (“LIBOR”) index or the Securities Industry and Financial Markets Association (“SIFMA”) index.
	Trading securities derivatives: The Company enters into interest rate derivative contracts to hedge interest rate and market value risks associated with its fixed income securities. The instruments use interest rates based upon either the Municipal Market Data (“MMD”) index, LIBOR or the SIFMA index. The Company also enters into credit default swap index contracts to hedge credit risk associated with its taxable fixed income securities and option contracts to hedge market value risk associated with its convertible securities and asset-backed securities.
	The following table presents the total absolute notional contract amount associated with the Company’s outstanding derivative instruments:
	(Dollars in thousands)				June 30,				December 31,
	Transaction Type or Hedged Security		Derivative Category		2014				2013
	Customer matched-book		Interest rate derivative contract		$	5,103,320			$	5,310,929
	Trading securities		Interest rate derivative contract		225,500				198,500
	Trading securities		Credit default swap index contract		457,904				299,333
	Trading securities		Equity option derivative contract		15,969				17,090
					$	5,802,693			$	5,825,852
	The Company’s derivative contracts do not qualify for hedge accounting, therefore, unrealized gains and losses are recorded on the consolidated statements of operations. The following table presents the Company’s unrealized gains/(losses) on derivative instruments:
					Three Months Ended								Six Months Ended
	(Dollars in thousands)				June 30,								June 30,
	Derivative Category		Operations Category		2014				2013				2014			2013
	Interest rate derivative contract		Investment banking		$	(844	)		$	(111	)		$	(1,369	)	$	(649	)
	Interest rate derivative contract		Institutional brokerage		(4,798		)		15,527				(4,266		)	21,462
	Credit default swap index contract		Institutional brokerage		(1,668		)		3,143				(2,922		)	1,268
	Equity option derivative contract		Institutional brokerage		(698		)		—				419			—
					$	(8,008	)		$	18,559			$	(8,138	)	$	22,081
	The gross fair market value of all derivative instruments and their location on the Company’s consolidated statements of financial condition prior to counterparty netting are shown below by asset or liability position:
	(Dollars in thousands)				Asset Value at						Liability Value at
					June 30,						June 30,
	Derivative Category		Financial Condition Location		2014				Financial Condition Location		2014
	Interest rate derivative contract		Financial instruments and other inventory positions owned		$	407,298			Financial instruments and other inventory positions sold,  but not yet purchased		$	393,755
	Credit default swap index contract		Financial instruments and other inventory positions owned		7,645				Financial instruments and other inventory positions sold,  but not yet purchased		11,790
	Equity option derivative contract		Financial instruments and other inventory positions owned		94				Financial instruments and other inventory positions sold,  but not yet purchased		1,379
					$	415,037					$	406,924
Derivatives are reported on a net basis by counterparty (i.e., the net payable or receivable for derivative assets and liabilities for a given counterparty) when a legal right of offset exists and on a net basis by cross product when applicable provisions are stated in master netting agreements. Cash collateral received or paid is netted on a counterparty basis, provided a legal right of offset exists.
Credit risk associated with the Company’s derivatives is the risk that a derivative counterparty will not perform in accordance with the terms of the applicable derivative contract. Credit exposure associated with the Company’s derivatives is driven by uncollateralized market movements in the fair value of the contracts with counterparties and is monitored regularly by the Company’s financial risk committee. The Company considers counterparty credit risk in determining derivative contract fair value. The majority of the Company’s  derivative contracts are substantially collateralized by its counterparties, who  are major  financial institutions. The Company has a limited number of counterparties who are not required to post collateral. Based on market movements, the uncollateralized amounts representing the fair value of the derivative contract can become material, exposing the Company to the credit risk of these counterparties. As of June 30, 2014, the Company had $25.5 million of uncollateralized credit exposure with these counterparties (notional contract amount of $199.5 million), including $12.9 million of uncollateralized credit exposure with one counterparty.

Fair_Value_of_Financial_Instru

Fair Value of Financial Instruments	6 Months Ended
	Jun. 30, 2014
Fair Value Disclosures [Abstract]	'
Fair Value of Financial Instruments	'
	Fair Value of Financial Instruments
	Based on the nature of the Company’s business and its role as a “dealer” in the securities industry or as a manager of alternative asset management funds, the fair values of its financial instruments are determined internally. The Company’s processes are designed to ensure that the fair values used for financial reporting are based on observable inputs wherever possible. In the event that observable inputs are not available, unobservable inputs are developed based on an evaluation of all relevant empirical market data, including prices evidenced by market transactions, interest rates, credit spreads, volatilities and correlations and other security-specific information. Valuation adjustments related to illiquidity or counterparty credit risk are also considered. In estimating fair value, the Company may utilize information provided by third-party pricing vendors to corroborate internally-developed fair value estimates.
	The Company employs specific control processes to determine the reasonableness of the fair value of its financial instruments. The Company’s processes are designed to ensure that the internally estimated fair values are accurately recorded and that the data inputs and the valuation techniques used are appropriate, consistently applied, and that the assumptions are reasonable and consistent with the objective of determining fair value. Individuals outside of the trading departments perform independent pricing verification reviews as of each reporting date. The Company has established parameters which set forth when the fair value of securities are independently verified. The selection parameters are generally based upon the type of security, the level of estimation risk of a security, the materiality of the security to the Company’s financial statements, changes in fair value from period to period, and other specific facts and circumstances of the Company’s securities portfolio. In evaluating the initial internally-estimated fair values made by the Company’s traders, the nature and complexity of securities involved (e.g., term, coupon, collateral, and other key drivers of value), level of market activity for securities, and availability of market data are considered. The independent price verification procedures include, but are not limited to, analysis of trade data (both internal and external where available), corroboration to the valuation of positions with similar characteristics, risks and components, or comparison to an alternative pricing source, such as a discounted cash flow model. The Company’s valuation committee, comprised of members of senior management and risk management, provides oversight and overall responsibility for the internal control processes and procedures related to fair value measurements.
	The following is a description of the valuation techniques used to measure fair value.
	Cash Equivalents
	Cash equivalents include highly liquid investments with original maturities of 90 days or less. Actively traded money market funds are measured at their net asset value and classified as Level I.
	Financial Instruments and Other Inventory Positions Owned
	The Company records financial instruments and other inventory positions owned and financial instruments and other inventory positions sold, but not yet purchased at fair value on the consolidated statements of financial condition with unrealized gains and losses reflected on the consolidated statements of operations.
	Equity securities – Exchange traded equity securities are valued based on quoted prices from the exchange for identical assets or liabilities as of the period-end date. To the extent these securities are actively traded and valuation adjustments are not applied, they are categorized as Level I. Non-exchange traded equity securities (principally hybrid preferred securities) are measured primarily using broker quotations, prices observed for recently executed market transactions and internally-developed fair value estimates based on observable inputs and are categorized within Level II of the fair value hierarchy.
	Convertible securities – Convertible securities are valued based on observable trades, when available. Accordingly, these convertible securities are categorized as Level II. When observable price quotations are not available, fair value is determined using model-based valuation techniques with observable market inputs, such as specific company stock price and volatility, and unobservable inputs such as option adjusted spreads over the U.S. treasury securities curve. These instruments are categorized as Level III.
	Corporate fixed income securities – Fixed income securities include corporate bonds which are valued based on recently executed market transactions of comparable size, internally-developed fair value estimates based on observable inputs, or broker quotations. Accordingly, these corporate bonds are categorized as Level II. When observable price quotations or certain observable inputs are not available, fair value is determined using model-based valuation techniques with observable inputs such as specific security contractual terms and yield curves, and unobservable inputs such as credit spreads over U.S. treasury securities. Corporate bonds measured using model-based valuation techniques are categorized as Level III.
	Taxable municipal securities – Taxable municipal securities are valued using recently executed observable trades or market price quotations and therefore are generally categorized as Level II.
	Tax-exempt municipal securities – Tax-exempt municipal securities are valued using recently executed observable trades or market price quotations and therefore are generally categorized as Level II. Certain illiquid tax-exempt municipal securities are valued using market data for comparable securities (maturity and sector) and management judgment to infer an appropriate current yield or other model-based valuation techniques deemed appropriate by management based on the specific nature of the individual security and are therefore categorized as Level III.
	Short-term municipal securities – Short-term municipal securities include auction rate securities, variable rate demand notes, and other short-term municipal securities. Variable rate demand notes and other short-term municipal securities are valued using recently executed observable trades or market price quotations and therefore are generally categorized as Level II. Auction rate securities with limited liquidity are categorized as Level III and are valued using discounted cash flow models with unobservable inputs such as the Company’s expected recovery rate on the securities.
	Asset-backed securities – Asset-backed securities are valued using observable trades, when available. Certain asset-backed securities are valued using models where inputs to the model are directly observable in the market, or can be derived principally from or corroborated by observable market data. These asset-backed securities are categorized as Level II. Other asset-backed securities, which are principally collateralized by residential mortgages, have experienced low volumes of executed transactions resulting in less observable transaction data. Certain asset-backed securities collateralized by residential mortgages are valued using cash flow models that utilize unobservable inputs including credit default rates, prepayment rates, loss severity and valuation yields. As judgment is used to determine the range of these inputs, these asset-backed securities are categorized as Level III.
	U.S. government agency securities – U.S. government agency securities include agency debt bonds and mortgage bonds. Agency debt bonds are valued by using either direct price quotes or price quotes for comparable bond securities and are categorized as Level II. Mortgage bonds include bonds secured by mortgages, mortgage pass-through securities, agency collateralized mortgage-obligation (“CMO”) securities and agency interest-only securities. Mortgage pass-through securities, CMO securities and interest-only securities are valued using recently executed observable trades or other observable inputs, such as prepayment speeds and therefore are generally categorized as Level II. Mortgage bonds are valued using observable market inputs, such as market yields ranging from 18-511 basis points (“bps”) on spreads over U.S. treasury securities, or models based upon prepayment expectations ranging from 47-328 Public Securities Association (“PSA”) prepayment levels. These securities are categorized as Level II.
	U.S. government securities – U.S. government securities include highly liquid U.S. treasury securities which are generally valued using quoted market prices and therefore categorized as Level I. The Company does not transact in securities of countries other than the U.S. government.
	Derivatives – Derivative contracts include interest rate and basis swaps, forward purchase agreements, interest rate locks, futures, options and credit default swap index contracts. These instruments derive their value from underlying assets, reference rates, indices or a combination of these factors. The Company's equity option derivative contracts are valued based on quoted prices from the exchange for identical assets or liabilities as of the period-end date. To the extent these contracts are actively traded and valuation adjustments are not applied, they are categorized as Level I. The Company’s credit default swap index contracts are valued using market price quotations and are classified as Level II. The majority of the Company’s interest rate derivative contracts, including both interest rate swaps and interest rate locks, are valued using market standard pricing models based on the net present value of estimated future cash flows. The valuation models used do not involve material subjectivity as the methodologies do not entail significant judgment and the pricing inputs are market observable, including contractual terms, yield curves and measures of volatility. These instruments are classified as Level II within the fair value hierarchy. Certain interest rate locks transact in less active markets and were valued using valuation models that included the previously mentioned observable inputs and certain unobservable inputs that required significant judgment, such as the premium over the MMD curve. These instruments are classified as Level III.
	Investments
	The Company’s investments valued at fair value include equity investments in private companies, investments in public companies, investments in registered mutual funds, and warrants of public or private companies. Exchange traded direct equity investments in public companies and registered mutual funds are valued based on quoted prices on active markets and classified as Level I. Company-owned warrants, which have a cashless exercise option, are valued based upon the Black-Scholes option-pricing model and certain unobservable inputs. The Company applies a liquidity discount to the value of its warrants in public and private companies. For warrants in private companies, valuation adjustments, based upon management’s judgment, are made to account for differences between the measured security and the stock volatility factors of comparable companies. Company-owned warrants are reported as Level III assets. Equity securities in private companies are valued based on an assessment of each underlying security, considering rounds of financing, third-party transactions and market-based information, including comparable company transactions, trading multiples and changes in market outlook, among other factors. These securities are generally categorized as Level III.
	Fair Value Option – The fair value option permits the irrevocable fair value option election on an instrument-by-instrument basis at initial recognition of an asset or liability or upon an event that gives rise to a new basis of accounting for that instrument. The fair value option was elected for certain merchant banking and other investments at inception to reflect economic events in earnings on a timely basis. Merchant banking and other equity investments of $16.8 million and $16.1 million, included within investments on the consolidated statements of financial condition, are accounted for at fair value and are classified as Level III assets at June 30, 2014 and December 31, 2013, respectively. The realized and unrealized gains from fair value changes included in earnings as a result of electing to apply the fair value option to certain financial assets were $1.0 million and $5.5 million for the six months ended June 30, 2014 and 2013, respectively.
	The following table summarizes quantitative information about the significant unobservable inputs used in the fair value measurement of the Company’s Level III financial instruments as of June 30, 2014:
		Valuation					Weighted
		Technique		Unobservable Input	Range		Average
	Assets:
	Financial instruments and other inventory positions owned:
	Municipal securities:
	Tax-exempt securities	Discounted cash flow		Debt service coverage ratio (2)	5 - 69%		22.20%
	Short-term securities	Discounted cash flow		Expected recovery rate (% of par) (2)	77 - 80%		79.60%
	Asset-backed securities:
	Collateralized by residential mortgages	Discounted cash flow		Credit default rates (3)	0 - 10%		3.60%
				Prepayment rates (4)	1 - 15%		4.30%
				Loss severity (3)	50 - 100%		58.30%
				Valuation yields (3)	3 - 8%		4.80%
	Derivative contracts:
	Interest rate locks	Discounted cash flow		Premium over the MMD curve (1)	27 - 41 bps		39.2 bps
	Investments at fair value:
	Warrants in public and private companies	Black-Scholes option pricing model		Liquidity discount rates (1)	30 - 40%		34.30%
	Warrants in private companies	Black-Scholes option pricing model		Stock volatility factors of comparable companies (2)	22 - 85%		40.60%
	Equity securities in private companies	Market approach		Revenue multiple (2)	2 - 7 times		3.7 times
				EBITDA multiple (2)	9 - 12 times		9.3 times
	Liabilities:
	Financial instruments and other inventory positions sold, but not yet purchased:
	Derivative contracts:
	Interest rate locks	Discounted cash flow		Premium over the MMD curve (1)	0 - 34 bps		14.2 bps
	Sensitivity of the fair value to changes in unobservable inputs:
	-1	Significant increase/(decrease) in the unobservable input in isolation would result in a significantly lower/(higher) fair value measurement.
	-2	Significant increase/(decrease) in the unobservable input in isolation would result in a significantly higher/(lower) fair value measurement.
	-3	Significant changes in any of these inputs in isolation could result in a significantly different fair value. Generally, a change in the assumption used for credit default rates is accompanied by a directionally similar change in the assumption used for the loss severity and a directionally inverse change in the assumption for valuation yields.
	-4	The potential impact of changes in prepayment rates on fair value is dependent on other security-specific factors, such as the par value and structure. Changes in the prepayment rates may result in directionally similar or directionally inverse changes in fair value depending on whether the security trades at a premium or discount to the par value.
	The following table summarizes the valuation of the Company’s financial instruments by pricing observability levels defined in FASB Accounting Standards Codification Topic 820, "Fair Value Measurement" ("ASC 820") as of June 30, 2014:
											Counterparty
											and Cash
											Collateral
	(Dollars in thousands)	Level I			Level II			Level III			Netting (1)			Total
	Assets:
	Financial instruments and other inventory positions owned:
	Corporate securities:
	Equity securities	$	36,713		$	19,262		$	—		$	—		$	55,975
	Convertible securities	—			94,496			—			—			94,496
	Fixed income securities	—			27,344			—			—			27,344
	Municipal securities:
	Taxable securities	—			237,126			—			—			237,126
Tax-exempt securities	—			466,231			1,306			—			467,537
Short-term securities	—			151,477			732			—			152,209
Asset-backed securities	—			4,593			129,126			—			133,719
U.S. government agency securities	—			245,365			—			—			245,365
U.S. government securities	8,185			—			—			—			8,185
Derivative contracts	94			414,316			627			(367,922		)	47,115
Total financial instruments and other inventory positions owned:	44,992			1,660,210			131,791			(367,922		)	1,469,071
Cash equivalents	1,318			—			—			—			1,318
Investments at fair value	29,919			—			58,567			—			88,486
Total assets	$	76,229		$	1,660,210		$	190,358		$	(367,922	)	$	1,558,875
Liabilities:
Financial instruments and other inventory positions sold, but not yet purchased:
Corporate securities:
Equity securities	$	96,733		$	229		$	—		$	—		$	96,962
Fixed income securities	—			9,974			—			—			9,974
U.S. government agency securities	—			49,009			—			—			49,009
U.S. government securities	345,756			—			—			—			345,756
Derivative contracts	1,379			394,699			10,846			(390,339		)	16,585
Total financial instruments and other inventory positions sold, but not yet purchased:	$	443,868		$	453,911		$	10,846		$	(390,339	)	$	518,286
-1	Represents cash collateral and the impact of netting on a counterparty basis. The Company had no securities posted as collateral to its counterparties.
The following table summarizes the valuation of the Company’s financial instruments by pricing observability levels defined in ASC 820 as of December 31, 2013:
										Counterparty
										and Cash
										Collateral
(Dollars in thousands)	Level I			Level II			Level III			Netting (1)			Total
Assets:
Financial instruments and other inventory positions owned:
Corporate securities:
Equity securities	$	39,711		$	14,386		$	—		$	—		$	54,097
Convertible securities	—			80,784			—			—			80,784
Fixed income securities	—			10,002			100			—			10,102
Municipal securities:
Taxable securities	—			232,379			—			—			232,379
Tax-exempt securities	—			459,432			1,433			—			460,865
Short-term securities	—			61,964			656			—			62,620
Asset-backed securities	—			12			119,799			—			119,811
U.S. government agency securities	—			304,737			—			—			304,737
Derivative contracts	19			351,589			691			(313,666		)	38,633
Total financial instruments and other inventory positions owned:	39,730			1,515,285			122,679			(313,666		)	1,364,028
Cash equivalents	101,629			—			—			—			101,629
Investments at fair value	20,690			—			49,240			—			69,930
Total assets	$	162,049		$	1,515,285		$	171,919		$	(313,666	)	$	1,535,587
Liabilities:
Financial instruments and other inventory positions sold, but not yet purchased:
Corporate securities:
Equity securities	$	69,205		$	—		$	—		$	—		$	69,205
Fixed income securities	—			24,021			—			—			24,021
U.S. government agency securities	—			120,084			—			—			120,084
U.S. government securities	291,320			—			—			—			291,320
Derivative contracts	1,889			324,065			6,643			(324,394		)	8,203
Total financial instruments and other inventory positions sold, but not yet purchased:	$	362,414		$	468,170		$	6,643		$	(324,394	)	$	512,833
-1	Represents cash collateral and the impact of netting on a counterparty basis. The Company had no securities posted as collateral to its counterparties.
The Company’s Level III assets were $190.4 million and $171.9 million, or 12.2 percent and 11.2 percent of financial instruments measured at fair value at June 30, 2014 and December 31, 2013, respectively. The value of transfers between levels are recognized at the beginning of the reporting period. There were no significant transfers between Level I, Level II or Level III for the six months ended June 30, 2014.
The following tables summarize the changes in fair value associated with Level III financial instruments held at the beginning or end of the periods presented:
	Balance at														Realized			Unrealized			Balance at
	March 31,									Transfers			Transfers		gains/			gains/			June 30,
(Dollars in thousands)	2014			Purchases			Sales			in			out		(losses) (1)			(losses) (1)			2014
Assets:
Financial instruments and other inventory positions owned:
Corporate securities:
Fixed income securities	$	100		$	—		$	(100	)	$	—		$	—	$	—		$	—		$	—
Municipal securities:
Tax-exempt securities	1,433			—			—			—			—		—			(127		)	1,306
Short-term securities	656			—			(25		)	—			—		6			95			732
Asset-backed securities	107,399			119,064			(101,878		)	—			—		4,678			(137		)	129,126
Derivative contracts	64			—			—			—			—		—			563			627
Total financial instruments and other inventory positions owned:	109,652			119,064			(102,003		)	—			—		4,684			394			131,791
Investments at fair value	60,954			—			(2,358		)	—			—		2,358			(2,387		)	58,567
Total assets	$	170,606		$	119,064		$	(104,361	)	$	—		$	—	$	7,042		$	(1,993	)	$	190,358
Liabilities:
Financial instruments and other inventory positions sold, but not yet purchased:
Derivative contracts	$	5,479		$	(8,343	)	$	—		$	—		$	—	$	8,343		$	5,367		$	10,846
Total financial instruments and other inventory positions sold, but not yet purchased:	$	5,479		$	(8,343	)	$	—		$	—		$	—	$	8,343		$	5,367		$	10,846
-1	Realized and unrealized gains/(losses) related to financial instruments, with the exception of customer matched-book derivatives, are reported in institutional brokerage on the consolidated statements of operations. Realized and unrealized gains/(losses) related to customer matched-book derivatives are reported in investment banking. Realized and unrealized gains/(losses) related to investments are reported in investment banking revenues or investment income/(loss) on the consolidated statements of operations.
	Balance at														Realized			Unrealized			Balance at
	March 31,									Transfers			Transfers		gains/			gains/			June 30,
(Dollars in thousands)	2013			Purchases			Sales			in			out		(losses) (1)			(losses) (1)			2013
Assets:
Financial instruments and other inventory positions owned:
Corporate securities:
Convertible securities	$	—		$	2,559		$	(2,308	)	$	870		$	—	$	9		$	178		$	1,308
Fixed income securities	—			100			—			—			—		—			—			100
Municipal securities:
Tax-exempt securities	1,431			—			—			—			—		—			2			1,433
Short-term securities	656			—			—			—			—		—			—			656
Asset-backed securities	107,654			162,754			(123,422		)	—			—		5,573			(1,163		)	151,396
Derivative contracts	2,372			710			(896		)	—			—		186			15,507			17,879
Total financial instruments and other inventory positions owned:	112,113			166,123			(126,626		)	870			—		5,768			14,524			172,772
Investments at fair value	41,653			10,000			—			—			—		—			1,914			53,567
Total assets	$	153,766		$	176,123		$	(126,626	)	$	870		$	—	$	5,768		$	16,438		$	226,339
Liabilities:
Financial instruments and other inventory positions sold, but not yet purchased:
Derivative contracts	$	399		$	—		$	745		$	—		$	—	$	(745	)	$	(145	)	$	254
Total financial instruments and other inventory positions sold, but not yet purchased:	$	399		$	—		$	745		$	—		$	—	$	(745	)	$	(145	)	$	254
-1	Realized and unrealized gains/(losses) related to financial instruments, with the exception of customer matched-book derivatives, are reported in institutional brokerage on the consolidated statements of operations. Realized and unrealized gains/(losses) related to customer matched-book derivatives are reported in investment banking. Realized and unrealized gains/(losses) related to investments are reported in investment banking revenues or investment income/(loss) on the consolidated statements of operations.
The following tables summarize the changes in fair value associated with Level III financial instruments held at the beginning or end of the periods presented:
	Balance at														Realized			Unrealized			Balance at
	December 31,									Transfers			Transfers		gains/			gains/			June 30,
(Dollars in thousands)	2013			Purchases			Sales			in			out		(losses) (1)			(losses) (1)			2014
Assets:
Financial instruments and other inventory positions owned:
Corporate securities:
Fixed income securities	$	100		$	—		$	(100	)	$	—		$	—	$	—		$	—		$	—
Municipal securities:
Tax-exempt securities	1,433			—			—			—			—		—			(127		)	1,306
Short-term securities	656			—			(25		)	—			—		6			95			732
Asset-backed securities	119,799			151,790			(150,621		)	—			—		9,184			(1,026		)	129,126
Derivative contracts	691			2,614			—			—			—		(2,614		)	(64		)	627
Total financial instruments and other inventory positions owned:	122,679			154,404			(150,746		)	—			—		6,576			(1,122		)	131,791
Investments at fair value	49,240			10,000			(2,358		)	—			—		2,358			(673		)	58,567
Total assets	$	171,919		$	164,404		$	(153,104	)	$	—		$	—	$	8,934		$	(1,795	)	$	190,358
Liabilities:
Financial instruments and other inventory positions sold, but not yet purchased:
Derivative contracts	$	6,643		$	(16,751	)	$	—		$	—		$	—	$	16,751		$	4,203		$	10,846
Total financial instruments and other inventory positions sold, but not yet purchased:	$	6,643		$	(16,751	)	$	—		$	—		$	—	$	16,751		$	4,203		$	10,846
-1	Realized and unrealized gains/(losses) related to financial instruments, with the exception of customer matched-book derivatives, are reported in institutional brokerage on the consolidated statements of operations. Realized and unrealized gains/(losses) related to customer matched-book derivatives are reported in investment banking. Realized and unrealized gains/(losses) related to investments are reported in investment banking revenues or investment income/(loss) on the consolidated statements of operations.
	Balance at														Realized			Unrealized			Balance at
	December 31,									Transfers			Transfers		gains/			gains/			June 30,
(Dollars in thousands)	2012			Purchases			Sales			in			out		(losses) (1)			(losses) (1)			2013
Assets:
Financial instruments and other inventory positions owned:
Corporate securities:
Convertible securities	$	—		$	2,559		$	(2,308	)	$	870		$	—	$	9		$	178		$	1,308
Fixed income securities	—			100			—			—			—		—			—			100
Municipal securities:
Tax-exempt securities	1,429			1			—			—			—		—			3			1,433
Short-term securities	656			—			—			—			—		—			—			656
Asset-backed securities	116,171			196,496			(170,569		)	—			—		16,295			(6,997		)	151,396
Derivative contracts	827			5			(134		)	—			—		43			17,138			17,879
Total financial instruments and other inventory positions owned:	119,083			199,161			(173,011		)	870			—		16,347			10,322			172,772
Investments at fair value	33,245			15,362			—			—			—		4			4,956			53,567
Total assets	$	152,328		$	214,523		$	(173,011	)	$	870		$	—	$	16,351		$	15,278		$	226,339
Liabilities:
Financial instruments and other inventory positions sold, but not yet purchased:
Derivative contracts	$	5,218		$	(5,650	)	$	405		$	—		$	—	$	5,232		$	(4,951	)	$	254
Total financial instruments and other inventory positions sold, but not yet purchased:	$	5,218		$	(5,650	)	$	405		$	—		$	—	$	5,232		$	(4,951	)	$	254
-1	Realized and unrealized gains/(losses) related to financial instruments, with the exception of customer matched-book derivatives, are reported in institutional brokerage on the consolidated statements of operations. Realized and unrealized gains/(losses) related to customer matched-book derivatives are reported in investment banking. Realized and unrealized gains/(losses) related to investments are reported in investment banking revenues or investment income/(loss) on the consolidated statements of operations.
The carrying values of the Company’s cash, securities either purchased or sold under agreements to resell, receivables and payables either from or to customers and brokers, dealers and clearing organizations and short-term financings approximate fair value due to their liquid or short-term nature.

Variable_Interest_Entities

Variable Interest Entities	6 Months Ended
	Jun. 30, 2014
Variable Interest Entities Disclosure [Abstract]	'
Variable Interest Entities	'
	Variable Interest Entities
	The Company has investments in and/or acts as the managing partner of various partnerships, limited liability companies, or registered mutual funds. These entities were established for the purpose of investing in securities of public or private companies, or municipal debt obligations and were initially financed through the capital commitments or seed investments of the members.
	Variable Interest Entities ("VIEs") are entities in which equity investors lack the characteristics of a controlling financial interest or do not have sufficient equity at risk for the entity to finance its activities. The determination as to whether an entity is a VIE is based on the amount and nature of the members’ equity investment in the entity. The Company also considers other characteristics such as the power through voting rights or similar rights to direct the activities of an entity that most significantly impact the entity’s economic performance. For those entities that meet the deferral provisions defined by FASB ASU No. 2010-10, "Consolidation: Amendments for Certain Investment Funds," ("ASU 2010-10"), the Company considers characteristics such as the ability to influence the decision making about the entity’s activities and how the entity is financed. The Company has identified certain of the entities described above as VIEs. These VIEs had net assets approximating $0.7 billion at June 30, 2014 and $0.8 billion at December 31, 2013, respectively. The Company’s exposure to loss from these VIEs is $11.5 million, which is the carrying value of its capital contributions recorded in investments on the consolidated statements of financial condition at June 30, 2014. The Company had no liabilities related to these VIEs at June 30, 2014 and December 31, 2013.
	The Company is required to consolidate all VIEs for which it is considered to be the primary beneficiary. The determination as to whether the Company is considered to be the primary beneficiary is based on whether the Company has both the power to direct the activities of the VIE that most significantly impact the entity’s economic performance and the obligation to absorb losses or the right to receive benefits of the VIE that could potentially be significant to the VIE. For those entities that meet the deferral provisions defined by ASU 2010-10, the determination as to whether the Company is considered to be the primary beneficiary differs in that it is based on whether the Company will absorb a majority of the VIE’s expected losses, receive a majority of the VIE’s expected residual returns, or both. The Company determined it is not the primary beneficiary of these VIEs and accordingly does not consolidate them. Furthermore, the Company has not provided financial or other support to these VIEs that it was not previously contractually required to provide as of June 30, 2014.
	The Company has investments in a grantor trust which was established as part of a nonqualified deferred compensation plan. The Company is the primary beneficiary of the grantor trust. Accordingly, the assets and liabilities of the grantor trust are consolidated by the Company on the consolidated statements of financial condition. See Note 19 for additional information on the nonqualified deferred compensation plan.
	The Company also originates CMOs through secondary market vehicles. The Company's risk of loss with respect to these entities is limited to the fair value of the securities held by the Company.

Receivables_from_and_Payables_

Receivables from and Payables to Brokers, Dealers and Clearing Organizations	6 Months Ended
	Jun. 30, 2014
Brokers and Dealers [Abstract]	'
Receivables from and Payables to Brokers, Dealers and Clearing Organizations	'
	Receivables from and Payables to Brokers, Dealers and Clearing Organizations
	Amounts receivable from brokers, dealers and clearing organizations included:
		June 30,		December 31,
	(Dollars in thousands)	2014		2013
	Receivable arising from unsettled securities transactions	$	34,030	$	59,657
	Deposits paid for securities borrowed	21,646		36,278
	Receivable from clearing organizations	14,864		966
	Deposits with clearing organizations	51,918		20,995
	Securities failed to deliver	14,504		593
	Other	21,528		8,624
		$	158,490	$	127,113
	Amounts payable to brokers, dealers and clearing organizations included:
		June 30,		December 31,
	(Dollars in thousands)	2014		2013
	Payable arising from unsettled securities transactions	$	206,464	$	5,643
	Payable to clearing organizations	13,088		9,462
	Securities failed to receive	5,491		744
	Other	15,495		11,873
		$	240,538	$	27,722
	Deposits paid for securities borrowed approximate the market value of the securities. Securities failed to deliver and receive represent the contract value of securities that have not been delivered or received by the Company on settlement date.

Collateralized_Securities_Tran

Collateralized Securities Transactions	6 Months Ended
	Jun. 30, 2014
Collateralized Securities Transactions Disclosure [Abstract]	'
Collateralized Securities Transactions	'
	Collateralized Securities Transactions
	The Company’s financing and customer securities activities involve the Company using securities as collateral. In the event that the counterparty does not meet its contractual obligation to return securities used as collateral (e.g., pursuant to the terms of a repurchase agreement), or customers do not deposit additional securities or cash for margin when required, the Company may be exposed to the risk of reacquiring the securities or selling the securities at unfavorable market prices in order to satisfy its obligations to its customers or counterparties. The Company seeks to control this risk by monitoring the market value of securities pledged or used as collateral on a daily basis and requiring adjustments in the event of excess market exposure. The Company also uses unaffiliated third party custodians to administer the underlying collateral for certain of its repurchase agreements and short-term financing to mitigate risk.
	In a reverse repurchase agreement the Company purchases financial instruments from a seller, typically in exchange for cash, and agrees to resell the same or substantially the same financial instruments to the seller at a stated price plus accrued interest in the future. In a repurchase agreement, the Company sells financial instruments to a buyer, typically for cash, and agrees to repurchase the same or substantially the same financial instruments from the buyer at a stated price plus accrued interest at a future date. Even though repurchase and reverse repurchase agreements involve the legal transfer of ownership of financial instruments, they are accounted for as financing arrangements because they require the financial instruments to be repurchased or resold at maturity of the agreement.
	In a securities borrowed transaction, the Company borrows securities from a counterparty in exchange for cash. When the Company returns the securities, the counterparty returns the cash. Interest is generally paid periodically over the life of the transaction.
	In the normal course of business, the Company obtains securities purchased under agreements to resell, securities borrowed and margin agreements on terms that permit it to repledge or resell the securities to others, typically pursuant to repurchase agreements. The Company obtained securities with a fair value of approximately $183.6 million and $212.4 million at June 30, 2014 and December 31, 2013, respectively, of which $174 million and $194.9 million, respectively, had been pledged or otherwise transferred to satisfy its commitments under financial instruments and other inventory positions sold, but not yet purchased.
	The following is a summary of the Company’s securities sold under agreements to repurchase ("Repurchase Liabilities"), the fair market value of collateral pledged and the interest rate charged by the Company’s counterparty, which is based on LIBOR plus an applicable margin, as of June 30, 2014:
		Repurchase		Fair Market
	(Dollars in thousands)	Liabilities		Value		Interest Rate
	Term up to 30 day maturities:
	Asset-backed securities	$	11,815	$	15,686	1.66 - 1.75%
	Reverse repurchase agreements, repurchase agreements and securities borrowed and loaned are reported on a net basis by counterparty when a legal right of offset exists.
	There were no gross amounts offset on the consolidated statements of financial condition for reverse repurchase agreements, securities borrowed or repurchase agreements at June 30, 2014 and December 31, 2013, respectively, as a legal right of offset did not exist. The Company had no outstanding securities lending arrangements as of June 30, 2014 or December 31, 2013. See Note 6 for information related to the Company's offsetting of derivative contracts.

Investments

Investments	6 Months Ended
	Jun. 30, 2014
Investments [Abstract]	'
Investments	'
	Investments
	The Company’s proprietary investments include investments in private companies and partnerships, registered mutual funds, warrants of public and private companies and private company debt. Investments included:
		June 30,			December 31,
	(Dollars in thousands)	2014			2013
	Investments at fair value	$	88,486		$	69,930
	Investments at cost	8,271			20,709
	Investments accounted for under the equity method	19,632			21,404
	Total investments	116,389			112,043
	Less investments attributable to noncontrolling interests (1)	(26,263		)	(21,137		)
		$	90,126		$	90,906
	-1	Noncontrolling interests are attributable to third party ownership in a consolidated merchant banking fund and private equity investment vehicles.
	Management regularly reviews the Company’s investments in private company debt for collectibility. At June 30, 2014, the Company had no private company debt investments.
	At June 30, 2014, investments carried on a cost basis had an estimated fair market value of $13.0 million. The estimated fair value of these investments was based on an assessment of each underlying security, considering rounds of financing, third-party transactions and market-based information, including comparable company transactions, trading multiples (e.g., multiples of revenue and earnings before interest, taxes, depreciation and amortization ("EBITDA")), among other factors. Because valuation estimates were based upon management’s judgment, investments carried at cost would be categorized as Level III assets in the fair value hierarchy, if they were carried at fair value.
	Investments accounted for under the equity method include general and limited partnership interests. The carrying value of these investments is based on the investment vehicle’s net asset value. The net assets of investment partnerships consist of investments in both marketable and non-marketable securities. The underlying investments held by such partnerships are valued based on the estimated fair value determined by management in our capacity as general partner or investor and, in the case of investments in unaffiliated investment partnerships, are based on financial statements prepared by the unaffiliated general partners.

Other_Assets

Other Assets	6 Months Ended
	Jun. 30, 2014
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]	'
Other Assets	'
	Other Assets
	Other assets included:
		June 30,		December 31,
	(Dollars in thousands)	2014		2013
	Net deferred income tax assets	$	31,310	$	36,252
	Fee receivables	33,306		34,415
	Accrued interest receivables	9,250		9,793
	Forgivable loans, net	9,164		7,879
	Prepaid expenses	5,294		5,237
	Other	10,028		8,516
	Total other assets	$	98,352	$	102,092

Goodwill_and_Intangible_Assets

Goodwill and Intangible Assets	6 Months Ended
	Jun. 30, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Goodwill and Intangible Assets	'
	Goodwill and Intangible Assets
	The following table presents the changes in the carrying value of goodwill and intangible assets from continuing operations for the six months ended June 30, 2014:
		Capital			Asset
	(Dollars in thousands)	Markets			Management			Total
	Goodwill
	Balance at December 31, 2013	$	13,790		$	196,844		$	210,634
	Goodwill acquired	—			—			—
	Impairment charge	—			—			—
	Adjustment	1,244			—			1,244
	Balance at June 30, 2014	$	15,034		$	196,844		$	211,878
	Intangible assets
	Balance at December 31, 2013	$	5,316		$	34,614		$	39,930
	Amortization of intangible assets	(1,486		)	(3,150		)	(4,636		)
	Balance at June 30, 2014	$	3,830		$	31,464		$	35,294

ShortTerm_Financing

Short-Term Financing	6 Months Ended
	Jun. 30, 2014
Debt Disclosure [Abstract]	'
Short-Term Financing	'
	Short-Term Financing
	The following is a summary of short-term financing and the weighted average interest rate on borrowings:
		Outstanding Balance				Weighted Average Interest Rate
		June 30,		December 31,		June 30,		December 31,
	(Dollars in thousands)	2014		2013		2014		2013
	Commercial paper (secured)	$	271,471	$	280,294	1.58	%	1.59	%
	Prime broker arrangement	90,930		234,417		0.91	%	0.9	%
	Total short-term financing	$	362,401	$	514,711
	The Company issues secured commercial paper to fund a portion of its securities inventory. The commercial paper notes (“CP Notes”) can be issued with maturities of 27 days to 270 days from the date of issuance. The CP Notes are issued under three separate programs, CP Series A, CP Series II A and CP Series III A, and are secured by different inventory classes. As of June 30, 2014, the weighted average maturity of CP Series A, CP Series II A and CP Series III A was 162 days, 99 days and 33 days, respectively. The CP Notes are interest bearing or sold at a discount to par with an interest rate based on LIBOR plus an applicable margin. CP Series III A includes a covenant that requires the Company’s U.S. broker dealer subsidiary to maintain excess net capital of $120 million.
	The Company has established an arrangement to obtain financing with a prime broker related to its municipal bond funds. Financing under this arrangement is secured by certain securities, primarily municipal securities, and collateral limitations could reduce the amount of funding available under this arrangement. The funding is at the discretion of the prime broker subject to a notice period.
	The Company has committed short-term bank line financing available on a secured basis and uncommitted short-term bank line financing available on both a secured and unsecured basis. The Company uses these credit facilities in the ordinary course of business to fund a portion of its daily operations and the amount borrowed under these credit facilities varies daily based on the Company’s funding needs.
	The Company’s committed short-term bank line financing at June 30, 2014 consisted of a one-year $250 million committed revolving credit facility with U.S. Bank, N.A., which was renewed in December 2013. Advances under this facility are secured by certain marketable securities. The facility includes a covenant that requires the Company’s U.S. broker dealer subsidiary to maintain minimum net capital of $120 million, and the unpaid principal amount of all advances under this facility will be due on December 27, 2014. The Company pays a nonrefundable commitment fee on the unused portion of the facility on a quarterly basis. At June 30, 2014, the Company had no advances against this line of credit.
	The Company’s uncommitted secured lines at June 30, 2014 totaled $185 million with two banks and are dependent on having appropriate collateral, as determined by the bank agreement, to secure an advance under the line. The availability of the Company’s uncommitted lines are subject to approval by the individual banks each time an advance is requested and may be denied. At June 30, 2014, the Company had no advances against these lines of credit.

Variable_Rate_Senior_Notes

Variable Rate Senior Notes	6 Months Ended
	Jun. 30, 2014
Debt Disclosure [Abstract]	'
Variable Rate Senior Notes	'
	Variable Rate Senior Notes
	On November 30, 2012, the Company entered into a note purchase agreement under which the Company issued unsecured variable rate senior notes ("Notes") in the amount of $125 million. The initial holders of the Notes are certain entities advised by PIMCO. The Notes consist of two classes, Class A Notes and Class B Notes, with principal amounts of $50 million and $75 million, respectively.
	On June 2, 2014, the Company entered into an amended and restated note purchase agreement ("Amended Note Purchase Agreement") under which the Company issued $50 million of new Class A Notes upon repayment in full of the 2012 Class A Notes. The Class A Notes bear interest at a rate equal to three-month LIBOR plus 3.00 percent and mature on May 31, 2017. The Class B Notes remain outstanding, bear interest at a rate equal to three-month LIBOR plus 4.50 percent and mature on November 30, 2015. Interest on the Notes is adjustable and payable quarterly. The unpaid principal amounts are due in full on the respective maturity dates and may not be prepaid by the Company.
	The Amended Note Purchase Agreement includes customary events of default, including failure to pay principal when due or failure to pay interest within five business days of when due, any representation or warranty in the Amended Note Purchase Agreement proving untrue in any material respect when made by the Company, failure to comply with the covenants in the Amended Note Purchase Agreement, failure to pay or another event of default under other material indebtedness in an amount exceeding $10 million, bankruptcy or insolvency of the Company or any of its subsidiaries or a change in control of the Company. If there is any event of default under the Amended Note Purchase Agreement, the noteholders may declare the entire principal and any accrued interest on the Notes to be due and payable and exercise other customary remedies.
	The Amended Note Purchase Agreement includes covenants that, among other things, require the Company to maintain a minimum consolidated tangible net worth and regulatory net capital, limit the Company's leverage ratio and require the Company to maintain a minimum ratio of operating cash flow to fixed charges. With respect to the net capital covenant, the Company's U.S. broker dealer subsidiary is required to maintain minimum net capital of $120 million. At June 30, 2014, the Company was in compliance with all covenants.
	The Notes are recorded at amortized cost. As of June 30, 2014, the carrying value of the Notes approximates fair value.

Contingencies_and_Commitments

Contingencies and Commitments	6 Months Ended
	Jun. 30, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Legal Contingencies	'
	Contingencies and Commitments
	Legal Contingencies
	The Company has been named as a defendant in various legal actions, including complaints and litigation and arbitration claims, arising from its business activities. Such actions include claims related to securities brokerage and investment banking activities, and certain class actions that primarily allege violations of securities laws and seek unspecified damages, which could be substantial. Also, the Company is involved from time to time in investigations and proceedings by governmental agencies and self-regulatory organizations (“SROs”) which could result in adverse judgments, settlement, penalties, fines or other relief.
	The Company has established reserves for potential losses that are probable and reasonably estimable that may result from pending and potential legal actions, investigations and regulatory proceedings. In many cases, however, it is inherently difficult to determine whether any loss is probable or even possible or to estimate the amount or range of any potential loss, particularly where proceedings may be in relatively early stages or where plaintiffs are seeking substantial or indeterminate damages. Matters frequently need to be more developed before a loss or range of loss can reasonably be estimated.
	Given uncertainties regarding the timing, scope, volume and outcome of pending and potential legal actions, investigations and regulatory proceedings and other factors, the amounts of reserves and ranges of reasonably possible losses are difficult to determine and of necessity subject to future revision. Subject to the foregoing, management of the Company believes, based on currently available information, after consultation with outside legal counsel and taking into account its established reserves, that pending legal actions, investigations and regulatory proceedings will be resolved with no material adverse effect on the consolidated statements of financial condition, results of operations or cash flows of the Company. However, if during any period a potential adverse contingency should become probable or resolved for an amount in excess of the established reserves, the results of operations and cash flows in that period and the financial condition as of the end of that period could be materially adversely affected. In addition, there can be no assurance that material losses will not be incurred from claims that have not yet been brought to the Company’s attention or are not yet determined to be reasonably possible.
	Operating Lease Commitments
	The Company leases office space throughout the United States and in a limited number of foreign countries where the Company’s international operations reside. Aggregate minimum lease commitments under operating leases as of June 30, 2014 are as follows:
	(Dollars in thousands)
	Remainder of 2014	$	5,242
	2015	11,957
	2016	11,871
	2017	9,877
	2018	9,563
	Thereafter	35,441
		$	83,951

Shareholders_Equity

Shareholders' Equity	6 Months Ended
	Jun. 30, 2014
Equity [Abstract]	'
Shareholders' Equity	'
	Shareholders’ Equity
	Share Repurchases
	In the third quarter of 2012, the Company’s board of directors authorized the repurchase of up to $100.0 million in common shares through September 30, 2014. During the six months ended June 30, 2014, the Company did not repurchase any shares of the Company's outstanding common stock related to this authorization. The Company has $39.5 million remaining under this authorization. The Company also purchases shares of common stock from restricted stock award recipients upon the award vesting as recipients sell shares to meet their employment tax obligations. The Company purchased 217,655 shares or $8.8 million of the Company’s common stock for this purpose during the six months ended June 30, 2014.
	Issuance of Shares
	During the six months ended June 30, 2014, the Company issued 103,598 common shares out of treasury stock in fulfillment of $4.2 million in obligations under the Piper Jaffray Companies Retirement Plan (the “Retirement Plan”) and issued 521,504 common shares out of treasury stock as a result of employee restricted share vesting and exercise transactions as discussed in Note 19. During the six months ended June 30, 2013, the Company issued 96,049 common shares out of treasury stock in fulfillment of $3.9 million in obligations under the Retirement Plan and issued 741,972 common shares out of treasury stock as a result of employee restricted share vesting.

Noncontrolling_Interests

Noncontrolling Interests	6 Months Ended
	Jun. 30, 2014
Noncontrolling Interest [Abstract]	'
Noncontrolling Interests	'
	Noncontrolling Interests
	The consolidated financial statements include the accounts of Piper Jaffray Companies, its wholly owned subsidiaries and other entities in which the Company has a controlling financial interest. Noncontrolling interests represent equity interests in consolidated entities that are not attributable, either directly or indirectly, to Piper Jaffray Companies. Noncontrolling interests include the minority equity holders’ proportionate share of the equity in a municipal bond fund of $115.6 million, a merchant banking fund of $18.5 million and private equity investment vehicles aggregating $7.8 million as of June 30, 2014. As of December 31, 2013, noncontrolling interests included the minority equity holders’ proportionate share of the equity in a municipal bond fund of $126.3 million, a merchant banking fund of $14.1 million and private equity investment vehicles aggregating $7.0 million.
	Ownership interests in entities held by parties other than the Company’s common shareholders are presented as noncontrolling interests within shareholders’ equity, separate from the Company’s own equity. Revenues, expenses and net income or loss are reported on the consolidated statements of operations on a consolidated basis, which includes amounts attributable to both the Company’s common shareholders and noncontrolling interests. Net income or loss is then allocated between the Company and noncontrolling interests based upon their relative ownership interests. Net income applicable to noncontrolling interests is deducted from consolidated net income to determine net income applicable to the Company. There was no other comprehensive income or loss attributed to noncontrolling interests for the six months ended June 30, 2014 and 2013, respectively.
		Common						Total
		Shareholders’			Noncontrolling			Shareholders’
	(Dollars in thousands)	Equity			Interests			Equity
	Balance at December 31, 2013	$	734,676		$	147,396		$	882,072
	Net income	35,961			7,293			43,254
	Amortization/issuance of restricted stock	20,163			—			20,163
	Issuance of treasury shares for options exercised	1,322			—			1,322
	Repurchase of common stock for employee tax withholding	(8,806		)	—			(8,806		)
	Issuance of treasury shares for 401k match	4,156			—			4,156
	Shares reserved/issued for director compensation	120			—			120
	Other comprehensive income	256			—			256
	Fund capital withdrawals, net	—			(12,780		)	(12,780		)
	Balance at June 30, 2014	$	787,848		$	141,909		$	929,757

Compensation_Plans

Compensation Plans	6 Months Ended
	Jun. 30, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Compensation Plans	'
	Compensation Plans
	Stock-Based Compensation Plans
	The Company maintains two stock-based compensation plans, the Piper Jaffray Companies Amended and Restated 2003 Annual and Long-Term Incentive Plan (the “Incentive Plan”) and the 2010 Employment Inducement Award Plan (the “Inducement Plan”). The Company’s equity awards are recognized on the consolidated statements of operations at grant date fair value over the service period of the award, net of estimated forfeitures.
	The following table provides a summary of the Company’s outstanding equity awards (in shares or units) as of June 30, 2014:
	Incentive Plan
	Restricted Stock
	Annual grants	825,343
	Sign-on grants	346,055
		1,171,398
	Inducement Plan
	Restricted Stock	29,159
	Total restricted stock related to compensation	1,200,557
	ARI deal consideration (1)	104,496
	Total restricted stock outstanding	1,305,053
	Incentive Plan
	Restricted Stock Units
	Leadership grants	405,826
	Incentive Plan
	Stock options outstanding	321,490
	-1	The Company issued restricted stock as part of deal consideration in conjunction with the acquisition of ARI.
	Incentive Plan
	The Incentive Plan permits the grant of equity awards, including restricted stock, restricted stock units and non-qualified stock options, to the Company’s employees and directors for up to 7.0 million shares of common stock (0.9 million shares remained available for future issuance under the Incentive Plan as of June 30, 2014). The Company believes that such awards help align the interests of employees and directors with those of shareholders and serve as an employee retention tool. The Incentive Plan provides for accelerated vesting of awards if there is a severance event, a change in control of the Company (as defined in the Incentive Plan), in the event of a participant’s death, and at the discretion of the compensation committee of the Company’s board of directors.
	Restricted Stock Awards
	Restricted stock grants are valued at the market price of the Company’s common stock on the date of grant and are amortized over the related requisite service period. The Company grants shares of restricted stock to current employees as part of year-end compensation (“Annual Grants”) and as a retention tool. Employees may receive restricted stock upon initial hiring or as a retention award (“Sign-on Grants”).
	The Company’s Annual Grants are made each year in February. Annual Grants vest ratably over three years in equal installments. The Annual Grants provide for continued vesting after termination of employment, so long as the employee does not violate certain post-termination restrictions set forth in the award agreement or any agreements entered into upon termination. The Company determined the service inception date precedes the grant date for the Annual Grants, and that the post-termination restrictions do not meet the criteria for an in-substance service condition, as defined by FASB Accounting Standards Codification Topic 718, "Compensation – Stock Compensation" ("ASC 718"). Accordingly, restricted stock granted as part of the Annual Grants is expensed in the one-year period in which those awards are deemed to be earned, which is generally the calendar year preceding the February grant date. For example, the Company recognized compensation expense during fiscal 2013 for its February 2014 Annual Grant. If an equity award related to the Annual Grants is forfeited as a result of violating the post-termination restrictions, the lower of the fair value of the award at grant date or the fair value of the award at the date of forfeiture is recorded within the consolidated statements of operations as a reversal of compensation expense.
	Sign-on Grants are used as a recruiting tool for new employees and are issued to current employees as a retention tool. These awards have both cliff and ratable vesting terms, and the employees must fulfill service requirements in exchange for rights to the awards. Compensation expense is amortized on a straight-line basis from the grant date over the requisite service period, generally two to five years. Employees forfeit unvested shares upon termination of employment and a reversal of compensation expense is recorded.
	Annually, the Company grants stock to its non-employee directors. The stock-based compensation paid to non-employee directors is fully expensed on the grant date and included within outside services expense on the consolidated statements of operations.
	Restricted Stock Units
	The Company granted annual restricted stock units to its leadership team (“Leadership Grants”) beginning in May 2012. The units will vest and convert to shares of common stock at the end of each 36-month performance period only if the Company satisfies predetermined market conditions over the performance period. Under the terms of the grants, the number of units that will vest and convert to shares will be based on the Company achieving specified market conditions during each performance period as described below. Compensation expense is amortized on a straight-line basis over the three-year requisite service period based on the fair value of the award on the grant date. The market condition must be met for the awards to vest and compensation cost will be recognized regardless if the market condition is satisfied. Employees forfeit unvested share units upon termination of employment with a corresponding reversal of compensation expense.
	Up to 50 percent of the award can be earned based on the Company’s total shareholder return relative to members of a predetermined peer group and up to 50 percent of the award can be earned based on the Company’s total shareholder return. The fair value of the awards on the grant date were determined using a Monte Carlo simulation with the following assumptions:
			Risk-free	Expected Stock
	Grant Year		Interest Rate	Price Volatility
	2014		0.82%	41.30%
	2013		0.40%	44.00%
	2012		0.38%	47.60%
	Because a portion of the award vesting depends on the Company’s total shareholder return relative to a peer group, the valuation modeled the performance of the peer group as well as the correlation between the Company and the peer group. The expected stock price volatility assumptions were determined using historical volatility as correlation coefficients can only be developed through historical volatility. The risk-free interest rates were determined based on three-year U.S. Treasury bond yields.
	Stock Options
	The Company previously granted options to purchase Piper Jaffray Companies common stock to employees and non-employee directors in fiscal years 2004 through 2008. Employee and director options were expensed by the Company on a straight-line basis over the required service period, based on the estimated fair value of the award on the date of grant using a Black-Scholes option-pricing model. As described above pertaining to the Company’s Annual Grants of restricted shares, stock options granted to employees were expensed in the calendar year preceding the annual February grant date. For example, the Company recognized compensation expense during fiscal 2007 for its February 2008 option grant. The maximum term of the stock options granted to employees and directors is ten years. The Company has not granted stock options since 2008.
	Inducement Plan
	In 2010, the Company established the Inducement Plan in conjunction with the acquisition of ARI. The Company granted $7.0 million in restricted stock (158,801 shares) under the Inducement Plan to ARI employees upon closing of the transaction. These shares vest ratably over five years in equal annual installments ending on March 1, 2015. Inducement Plan awards are amortized as compensation expense on a straight-line basis over the vesting period. Employees forfeit unvested Inducement Plan shares upon termination of employment and a reversal of compensation expense is recorded.
	Stock-Based Compensation Activity
	The Company recorded total compensation expense within continuing operations of $8.1 million and $3.8 million for the three months ended June 30, 2014 and 2013, respectively, and $13.3 million and $4.4 million for the six months ended June 30, 2014 and 2013, respectively, related to employee restricted stock and restricted stock unit awards. Total compensation cost includes year-end compensation for Annual Grants and the amortization of Sign-on Grants, less forfeitures of $0.4 million and $0.7 million for the three months and six months ended June 30, 2013, respectively. Forfeitures were immaterial for the six months ended June 30, 2014. The tax benefit related to stock-based compensation costs totaled $3.1 million and $1.5 million for the three months ended June 30, 2014 and 2013, respectively, and $5.2 million and $1.7 million for the six months ended June 30, 2014 and 2013, respectively.
	The following table summarizes the changes in the Company’s unvested restricted stock (including the unvested restricted stock issued as part of the deal consideration for ARI) under the Incentive Plan and Inducement Plan for the six months ended June 30, 2014:
		Unvested		Weighted Average
		Restricted Stock		Grant Date
		(in Shares)		Fair Value
	December 31, 2013	1,582,062		$	35.25
	Granted	404,474		40.13
	Vested	(675,940	)	35.99
	Canceled	(5,543	)	33.72
	June 30, 2014	1,305,053		$	36.39
	The following summarizes the changes in the Company’s unvested restricted stock units under the Incentive Plan for the six months ended June 30, 2014:
		Unvested		Weighted Average
		Restricted		Grant Date
		Stock Units		Fair Value
	December 31, 2013	290,536		$	15.83
	Granted	115,290		23.42
	Vested	—		—
	Canceled	—		—
	June 30, 2014	405,826		$	17.99
	As of June 30, 2014, there was $12.7 million of total unrecognized compensation cost related to restricted stock and restricted stock units expected to be recognized over a weighted average period of 2.67 years.
	The following table summarizes the changes in the Company’s outstanding stock options for the six months ended June 30, 2014:
						Weighted Average
			Weighted		Remaining
	Options		Average		Contractual Term	Aggregate
	Outstanding		Exercise Price		(in Years)	Intrinsic Value
December 31, 2013	469,289		$	44.83	2	$	288,318
Granted	—		—
Exercised	(34,247	)	35.75
Canceled	(55	)	39.62
Expired	(113,497	)	47.72
June 30, 2014	321,490		$	44.78	2.2	$	3,125,267
Options exercisable at June 30, 2014	321,490		$	44.78	2.2	$	3,125,267
As of June 30, 2014, there was no unrecognized compensation cost related to stock options expected to be recognized over future years.
The intrinsic value and resulting tax benefit realized from option exercises were immaterial for the six months ended June 30, 2014 and 2013, respectively.
Deferred Compensation Plans
In 2013, the Company adopted a nonqualified deferred compensation plan, an unfunded plan which allows certain highly compensated employees, at their election, to defer a percentage of their base salary, commissions and/or cash bonuses. The deferrals vest immediately and are non-forfeitable. The amounts deferred under this plan are held in a grantor trust. The Company invests, as a principal, in investments to economically hedge its obligation under the nonqualified deferred compensation plan. Investments in the grantor trust, consisting of mutual funds, totaled $6.1 million as of June 30, 2014, and are included in investments on the consolidated statements of financial condition. The compensation deferred by the employees is expensed in the period earned. The deferred compensation liability was $6.1 million as of June 30, 2014. Changes in the fair value of the investments made by the Company are reported in investment income/(loss) and changes in the corresponding deferred compensation liability are reflected as compensation and benefits expenses on the consolidated statements of operations.
In 2012, the Company established the Piper Jaffray Companies Mutual Fund Restricted Share Investment Plan, a deferred compensation plan which allows eligible employees to elect to receive a portion of the incentive compensation they would otherwise receive in the form of restricted stock, instead in MFRS Awards of registered funds managed by the Company's asset management business. MFRS Awards are awarded to qualifying employees in February of each year, and represent a portion of their compensation for performance in the preceding year similar to the Company's Annual Grants. MFRS Awards vest ratably over three years in equal installments and provide for continued vesting after termination of employment so long as the employee does not violate certain post-termination restrictions set forth in the award agreement or any agreement entered into upon termination. Forfeitures are recorded as a reduction of compensation and benefits expense within the consolidated statements of operations.
The Company has also granted MFRS Awards to new employees as a recruiting tool. Employees must fulfill service requirements in exchange for rights to the awards. Compensation expense from these awards will be amortized on a straight-line basis over the requisite service period of two to five years.

Earnings_Per_Share

Earnings Per Share	6 Months Ended
	Jun. 30, 2014
Earnings Per Share [Abstract]	'
Earnings Per Share	'
	Earnings Per Share
	The Company calculates earnings per share using the two-class method. Basic earnings per common share is computed by dividing net income/(loss) applicable to Piper Jaffray Companies’ common shareholders by the weighted average number of common shares outstanding for the period. Net income/(loss) applicable to Piper Jaffray Companies’ common shareholders represents net income/(loss) applicable to Piper Jaffray Companies reduced by the allocation of earnings to participating securities. Losses are not allocated to participating securities. All of the Company’s unvested restricted shares are deemed to be participating securities as they are eligible to share in the profits (e.g., receive dividends) of the Company. The Company’s unvested restricted stock units are not participating securities as they are not eligible to share in the profits of the Company. Diluted earnings per common share is calculated by adjusting the weighted average outstanding shares to assume conversion of all potentially dilutive stock options.
	The computation of earnings per share is as follows:
		Three Months Ended						Six Months Ended
		June 30,						June 30,
	(Amounts in thousands, except per share data)	2014			2013			2014			2013
	Net income from continuing operations applicable to Piper Jaffray Companies	$	18,213		$	4,359		$	35,961		$	15,026
	Net loss from discontinued operations	—			(1,871		)	—			(2,392		)
	Net income applicable to Piper Jaffray Companies	18,213			2,488			35,961			12,634
	Earnings allocated to participating securities (1)	(1,496		)	(222		)	(3,155		)	(1,301		)
	Net income applicable to Piper Jaffray Companies’ common shareholders (2)	$	16,717		$	2,266		$	32,806		$	11,333
	Shares for basic and diluted calculations:
	Average shares used in basic computation	14,958			15,621			14,786			15,602
	Stock options	55			5			50			17
	Average shares used in diluted computation	15,013			15,626			14,836			15,619
	Earnings/(loss) per basic common share:
	Income from continuing operations	$	1.12		$	0.25		$	2.22		$	0.86
	Loss from discontinued operations	—			(0.11		)	—			(0.14		)
	Earnings per basic common share	$	1.12		$	0.15		$	2.22		$	0.73
	Earnings/(loss) per diluted common share:
	Income from continuing operations	$	1.11		$	0.25		$	2.21		$	0.86
	Loss from discontinued operations	—			(0.11		)	—			(0.14		)
	Earnings per diluted common share	$	1.11		$	0.15		$	2.21		$	0.73
	-1	Represents the allocation of earnings to participating securities. Losses are not allocated to participating securities. Participating securities include all of the Company’s unvested restricted shares. The weighted average participating shares outstanding were 1,343,399 and 1,531,100 for the three months ended June 30, 2014 and 2013, respectively, and 1,426,656 and 1,791,940 for the six months ended June 30, 2014 and 2013, respectively.
	-2	Net income/(loss) applicable to Piper Jaffray Companies’ common shareholders for diluted and basic EPS may differ under the two-class method as a result of adding the effect of the assumed exercise of stock options to dilutive shares outstanding, which alters the ratio used to allocate earnings to Piper Jaffray Companies’ common shareholders and participating securities for purposes of calculating diluted and basic EPS.
	The anti-dilutive effects from stock options were immaterial for the six months ended June 30, 2014 and 2013.

Segment_Reporting

Segment Reporting	6 Months Ended
	Jun. 30, 2014
Segment Reporting [Abstract]	'
Segment Reporting	'
	Segment Reporting
	Basis for Presentation
	The Company structures its segments primarily based upon the nature of the financial products and services provided to customers and the Company’s management organization. The Company evaluates performance and allocates resources based on segment pre-tax operating income or loss and segment pre-tax operating margin. Revenues and expenses directly associated with each respective segment are included in determining their operating results. Other revenues and expenses that are not directly attributable to a particular segment are allocated based upon the Company’s allocation methodologies, including each segment’s respective net revenues, use of shared resources, headcount or other relevant measures. The financial management of assets is performed on an enterprise-wide basis. As such, assets are not assigned to the business segments.
	Segment pre-tax operating income and segment pre-tax operating margin exclude the results of discontinued operations.
	Reportable segment financial results from continuing operations are as follows:
		Three Months Ended						Six Months Ended
		June 30,						June 30,
	(Dollars in thousands)	2014			2013			2014			2013
	Capital Markets
	Investment banking
	Financing
	Equities	$	44,058		$	21,772		$	79,359		$	36,075
	Debt	20,174			22,131			33,713			39,163
	Advisory services	39,695			9,394			79,423			18,950
	Total investment banking	103,927			53,297			192,495			94,188
	Institutional sales and trading
	Equities	18,366			21,384			42,626			42,119
	Fixed income	21,085			8,261			46,323			32,649
	Total institutional sales and trading	39,451			29,645			88,949			74,768
	Management and performance fees	1,388			564			3,125			1,583
	Investment income	4,998			184			15,376			6,321
	Long-term financing expenses	(1,705		)	(1,872		)	(3,445		)	(3,821		)
	Net revenues	148,059			81,818			296,500			173,039
	Operating expenses (1)	124,691			83,937			245,621			162,395
	Segment pre-tax operating income/(loss)	$	23,368		$	(2,119	)	$	50,879		$	10,644
	Segment pre-tax operating margin	15.8		%	(2.6		)%	17.2		%	6.2		%
		Three Months Ended						Six Months Ended
		June 30,						June 30,
	(Dollars in thousands)	2014			2013			2014			2013
	Asset Management
	Management and performance fees
	Management fees	$	20,600		$	17,558		$	39,736		$	34,644
	Performance fees	278			305			364			656
	Total management and performance fees	20,878			17,863			40,100			35,300
	Investment income	1,094			91			1,564			966
	Net revenues	21,972			17,954			41,664			36,266
	Operating expenses (1)	14,923			12,502			29,413			25,409
	Segment pre-tax operating income	$	7,049		$	5,452		$	12,251		$	10,857
	Segment pre-tax operating margin	32.1		%	30.4		%	29.4		%	29.9		%
	Total
	Net revenues	$	170,031		$	99,772		$	338,164		$	209,305
	Operating expenses (1)	139,614			96,439			275,034			187,804
	Pre-tax operating income	$	30,417		$	3,333		$	63,130		$	21,501
	Pre-tax operating margin	17.9		%	3.3		%	18.7		%	10.3		%
	-1	Operating expenses include intangible asset amortization expense as set forth in the table below:
		Three Months Ended						Six Months Ended
		June 30,						June 30,
	(Dollars in thousands)	2014			2013			2014			2013
	Capital Markets	$	743		$	—		$	1,486		$	—
	Asset Management	1,575			1,661			3,150			3,322
	Total intangible asset amortization expense	$	2,318		$	1,661		$	4,636		$	3,322
	Geographic Areas
	The Company operates in both U.S. and non-U.S. markets. The Company’s non-U.S. business activities are principally conducted through European locations. Net revenues and long-lived assets for the Company's Asian location was not significant. Net revenues disclosed in the following table reflect the regional view, with financing revenues allocated to geographic locations based upon the location of the capital market, advisory revenues allocated based upon the location of the investment banking team and net institutional sales and trading revenues allocated based upon the location of the client. Asset management revenues are allocated to the U.S. based upon the geographic location of the Company’s asset management team. Net revenues exclude discontinued operations for all periods presented.
		Three Months Ended						Six Months Ended
		June 30,						June 30,
	(Dollars in thousands)	2014			2013			2014			2013
	Net revenues:
	United States	$	167,552		$	97,195		$	332,876		$	202,921
	Europe	2,479			2,577			5,288			6,384
	Consolidated	$	170,031		$	99,772		$	338,164		$	209,305
	Long-lived assets are allocated to geographic locations based upon the location of the asset. The following table presents long-lived assets by geographic region:
		June 30,			December 31,
	(Dollars in thousands)	2014			2013
Long-lived assets:
United States	$	287,737		$	296,516
Europe	6,396			6,414
Consolidated	$	294,133		$	302,930

Net_Capital_Requirements_and_O

Net Capital Requirements and Other Regulatory Matters	6 Months Ended
	Jun. 30, 2014
Banking and Thrift [Abstract]	'
Net Capital Requirements and Other Regulatory Matters	'
	Net Capital Requirements and Other Regulatory Matters
	Piper Jaffray is registered as a securities broker dealer with the SEC and is a member of various SROs and securities exchanges. The Financial Industry Regulatory Authority (“FINRA”) serves as Piper Jaffray’s primary SRO. Piper Jaffray is subject to the uniform net capital rule of the SEC and the net capital rule of FINRA. Piper Jaffray has elected to use the alternative method permitted by the SEC rule, which requires that it maintain minimum net capital of the greater of $1.0 million or 2 percent of aggregate debit balances arising from customer transactions, as such term is defined in the SEC rule. Under its rules, FINRA may prohibit a member firm from expanding its business or paying dividends if resulting net capital would be less than 5 percent of aggregate debit balances. Advances to affiliates, repayment of subordinated debt, dividend payments and other equity withdrawals by Piper Jaffray are subject to certain notification and other provisions of SEC and FINRA rules. In addition, Piper Jaffray is subject to certain notification requirements related to withdrawals of excess net capital.
	At June 30, 2014, net capital calculated under the SEC rule was $160.5 million, and exceeded the minimum net capital required under the SEC rule by $159.1 million.
	The Company’s committed short-term credit facility and its variable rate senior notes include covenants requiring Piper Jaffray to maintain minimum net capital of $120 million. CP Notes issued under CP Series III A include a covenant that requires Piper Jaffray to maintain excess net capital of $120 million.
	Piper Jaffray Ltd., a broker dealer subsidiary registered in the United Kingdom, was subject to the capital requirements of the Prudential Regulation Authority and the Financial Conduct Authority. As of June 30, 2014, Piper Jaffray Ltd. was in compliance with the capital requirements of the Prudential Regulation Authority and the Financial Conduct Authority.

Acquisitions_Tables

Acquisitions (Tables)	6 Months Ended
	Jun. 30, 2014
Business Combinations [Abstract]	'
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed	'
	The following table summarizes the estimated fair values of assets acquired and liabilities assumed at the respective dates of acquisition:
	(Dollars in thousands)
	Assets
	Cash and cash equivalents		$	8,014
	Financial instruments and other inventory positions owned		24,074
	Fixed assets		1,247
	Goodwill		15,034
	Intangible assets		6,665
	Other assets		7,678
	Total assets acquired		62,712
	Liabilities
	Payables		1,126
	Financial instruments and other inventory positions sold, but not yet purchased		22,588
	Accrued compensation		1,469
	Other liabilities and accrued expenses		4,789
	Total liabilities assumed		29,972
	Net assets acquired		$	32,740
Business Acquisition, Pro Forma Information	'
	The consolidated Company's unaudited pro forma information presented does not necessarily reflect the results of operations that would have resulted had the acquisitions been completed at the beginning of the applicable period presented, does not contemplate anticipated operational efficiencies of the combined entities, nor does it indicate the results of operations in future periods.
		Three Months Ended			Six Months Ended
	(Dollars in thousands)	June 30, 2013			June 30, 2013
	Net revenues	$	107,415		$	220,955
	Net income from continuing operations applicable to Piper Jaffray Companies	$	4,260		$	13,356

Financial_Instruments_and_Othe1

Financial Instruments and Other Inventory Positions Owned and Financial Instruments and Other Inventory Positions Sold, but Not Yet Purchased (Tables)	6 Months Ended
	Jun. 30, 2014
Disclosure Financial Instruments And Other Inventory Positions Owned And Financial Instruments And Other Inventory Positions Sold But Not Yet Purchased [Abstract]	'
Financial Instruments and Other Inventory Positions Owned and Financial Instruments and Other Inventory Positions Sold, but not yet Purchased	'
	Financial instruments and other inventory positions owned and financial instruments and other inventory positions sold, but not yet purchased were as follows:
		June 30,				December 31,
	(Dollars in thousands)	2014				2013
	Financial instruments and other inventory positions owned:
	Corporate securities:
	Equity securities	$	55,975			$	54,097
	Convertible securities	94,496				80,784
	Fixed income securities	27,344				10,102
	Municipal securities:
	Taxable securities	237,126				232,379
	Tax-exempt securities	467,537				460,865
	Short-term securities	152,209				62,620
	Asset-backed securities	133,719				119,811
	U.S. government agency securities	245,365				304,737
	U.S. government securities	8,185				—
	Derivative contracts	47,115				38,633
	Total financial instruments and other inventory positions owned	1,469,071				1,364,028
	Less noncontrolling interests (1)	(251,519		)		(291,513		)
		$	1,217,552			$	1,072,515
	Financial instruments and other inventory positions sold, but not yet purchased:
	Corporate securities:
	Equity securities	$	96,962			$	69,205
	Fixed income securities	9,974				24,021
	U.S. government agency securities	49,009				120,084
	U.S. government securities	345,756				291,320
	Derivative contracts	16,585				8,203
	Total financial instruments and other inventory positions sold, but not yet purchased	518,286				512,833
	Less noncontrolling interests (2)	(87,087		)		(68,356		)
		$	431,199			$	444,477
	-1	Noncontrolling interests attributable to third party ownership in a consolidated municipal bond fund consist of $109.7 million and $101.8 million of taxable municipal securities, $137.1 million and $183.9 million of tax-exempt municipal securities, and $4.8 million and $5.8 million of derivative contracts as of June 30, 2014 and December 31, 2013, respectively.
	-2	Noncontrolling interests attributable to third party ownership in a consolidated municipal bond fund consist of $85.5 million and $67.4 million of U.S. government securities, and $1.6 million and $1.0 million of derivative contracts as of June 30, 2014 and December 31, 2013, respectively.
Total Absolute Notional Contract Amount	'
	The following table presents the total absolute notional contract amount associated with the Company’s outstanding derivative instruments:
	(Dollars in thousands)				June 30,				December 31,
	Transaction Type or Hedged Security		Derivative Category		2014				2013
	Customer matched-book		Interest rate derivative contract		$	5,103,320			$	5,310,929
	Trading securities		Interest rate derivative contract		225,500				198,500
	Trading securities		Credit default swap index contract		457,904				299,333
	Trading securities		Equity option derivative contract		15,969				17,090
					$	5,802,693			$	5,825,852
Unrealized Gains/(Losses) on Derivative Instruments	'
	The following table presents the Company’s unrealized gains/(losses) on derivative instruments:
					Three Months Ended								Six Months Ended
	(Dollars in thousands)				June 30,								June 30,
	Derivative Category		Operations Category		2014				2013				2014			2013
	Interest rate derivative contract		Investment banking		$	(844	)		$	(111	)		$	(1,369	)	$	(649	)
	Interest rate derivative contract		Institutional brokerage		(4,798		)		15,527				(4,266		)	21,462
	Credit default swap index contract		Institutional brokerage		(1,668		)		3,143				(2,922		)	1,268
	Equity option derivative contract		Institutional brokerage		(698		)		—				419			—
					$	(8,008	)		$	18,559			$	(8,138	)	$	22,081
Gross Fair Market Value of Derivative Instruments and Location on Consolidated Statements of Financial Condition Prior to Counterparty and Cash Collateral Netting by Asset or Liability Position	'
	The gross fair market value of all derivative instruments and their location on the Company’s consolidated statements of financial condition prior to counterparty netting are shown below by asset or liability position:
	(Dollars in thousands)				Asset Value at						Liability Value at
					June 30,						June 30,
	Derivative Category		Financial Condition Location		2014				Financial Condition Location		2014
	Interest rate derivative contract		Financial instruments and other inventory positions owned		$	407,298			Financial instruments and other inventory positions sold,  but not yet purchased		$	393,755
	Credit default swap index contract		Financial instruments and other inventory positions owned		7,645				Financial instruments and other inventory positions sold,  but not yet purchased		11,790
	Equity option derivative contract		Financial instruments and other inventory positions owned		94				Financial instruments and other inventory positions sold,  but not yet purchased		1,379
					$	415,037					$	406,924

Fair_Value_of_Financial_Instru1

Fair Value of Financial Instruments (Tables)	6 Months Ended
	Jun. 30, 2014
Fair Value Disclosures [Abstract]	'
Information about Significant Unobservable Inputs used in Fair Value Measurement	'
	The following table summarizes quantitative information about the significant unobservable inputs used in the fair value measurement of the Company’s Level III financial instruments as of June 30, 2014:
		Valuation					Weighted
		Technique		Unobservable Input	Range		Average
	Assets:
	Financial instruments and other inventory positions owned:
	Municipal securities:
	Tax-exempt securities	Discounted cash flow		Debt service coverage ratio (2)	5 - 69%		22.20%
	Short-term securities	Discounted cash flow		Expected recovery rate (% of par) (2)	77 - 80%		79.60%
	Asset-backed securities:
	Collateralized by residential mortgages	Discounted cash flow		Credit default rates (3)	0 - 10%		3.60%
				Prepayment rates (4)	1 - 15%		4.30%
				Loss severity (3)	50 - 100%		58.30%
				Valuation yields (3)	3 - 8%		4.80%
	Derivative contracts:
	Interest rate locks	Discounted cash flow		Premium over the MMD curve (1)	27 - 41 bps		39.2 bps
	Investments at fair value:
	Warrants in public and private companies	Black-Scholes option pricing model		Liquidity discount rates (1)	30 - 40%		34.30%
	Warrants in private companies	Black-Scholes option pricing model		Stock volatility factors of comparable companies (2)	22 - 85%		40.60%
	Equity securities in private companies	Market approach		Revenue multiple (2)	2 - 7 times		3.7 times
				EBITDA multiple (2)	9 - 12 times		9.3 times
	Liabilities:
	Financial instruments and other inventory positions sold, but not yet purchased:
	Derivative contracts:
	Interest rate locks	Discounted cash flow		Premium over the MMD curve (1)	0 - 34 bps		14.2 bps
	Sensitivity of the fair value to changes in unobservable inputs:
	-1	Significant increase/(decrease) in the unobservable input in isolation would result in a significantly lower/(higher) fair value measurement.
	-2	Significant increase/(decrease) in the unobservable input in isolation would result in a significantly higher/(lower) fair value measurement.
	-3	Significant changes in any of these inputs in isolation could result in a significantly different fair value. Generally, a change in the assumption used for credit default rates is accompanied by a directionally similar change in the assumption used for the loss severity and a directionally inverse change in the assumption for valuation yields.
	-4	The potential impact of changes in prepayment rates on fair value is dependent on other security-specific factors, such as the par value and structure. Changes in the prepayment rates may result in directionally similar or directionally inverse changes in fair value depending on whether the security trades at a premium or discount to the par value.
Valuation of Financial Instruments by Pricing Observability Levels	'
	The following table summarizes the valuation of the Company’s financial instruments by pricing observability levels defined in FASB Accounting Standards Codification Topic 820, "Fair Value Measurement" ("ASC 820") as of June 30, 2014:
											Counterparty
											and Cash
											Collateral
	(Dollars in thousands)	Level I			Level II			Level III			Netting (1)			Total
	Assets:
	Financial instruments and other inventory positions owned:
	Corporate securities:
	Equity securities	$	36,713		$	19,262		$	—		$	—		$	55,975
	Convertible securities	—			94,496			—			—			94,496
	Fixed income securities	—			27,344			—			—			27,344
	Municipal securities:
	Taxable securities	—			237,126			—			—			237,126
	Tax-exempt securities	—			466,231			1,306			—			467,537
	Short-term securities	—			151,477			732			—			152,209
	Asset-backed securities	—			4,593			129,126			—			133,719
	U.S. government agency securities	—			245,365			—			—			245,365
	U.S. government securities	8,185			—			—			—			8,185
	Derivative contracts	94			414,316			627			(367,922		)	47,115
	Total financial instruments and other inventory positions owned:	44,992			1,660,210			131,791			(367,922		)	1,469,071
	Cash equivalents	1,318			—			—			—			1,318
	Investments at fair value	29,919			—			58,567			—			88,486
	Total assets	$	76,229		$	1,660,210		$	190,358		$	(367,922	)	$	1,558,875
	Liabilities:
	Financial instruments and other inventory positions sold, but not yet purchased:
	Corporate securities:
	Equity securities	$	96,733		$	229		$	—		$	—		$	96,962
	Fixed income securities	—			9,974			—			—			9,974
	U.S. government agency securities	—			49,009			—			—			49,009
	U.S. government securities	345,756			—			—			—			345,756
	Derivative contracts	1,379			394,699			10,846			(390,339		)	16,585
	Total financial instruments and other inventory positions sold, but not yet purchased:	$	443,868		$	453,911		$	10,846		$	(390,339	)	$	518,286
	-1	Represents cash collateral and the impact of netting on a counterparty basis. The Company had no securities posted as collateral to its counterparties.
	The following table summarizes the valuation of the Company’s financial instruments by pricing observability levels defined in ASC 820 as of December 31, 2013:
											Counterparty
											and Cash
											Collateral
	(Dollars in thousands)	Level I			Level II			Level III			Netting (1)			Total
	Assets:
	Financial instruments and other inventory positions owned:
	Corporate securities:
	Equity securities	$	39,711		$	14,386		$	—		$	—		$	54,097
	Convertible securities	—			80,784			—			—			80,784
	Fixed income securities	—			10,002			100			—			10,102
	Municipal securities:
	Taxable securities	—			232,379			—			—			232,379
	Tax-exempt securities	—			459,432			1,433			—			460,865
	Short-term securities	—			61,964			656			—			62,620
	Asset-backed securities	—			12			119,799			—			119,811
	U.S. government agency securities	—			304,737			—			—			304,737
	Derivative contracts	19			351,589			691			(313,666		)	38,633
	Total financial instruments and other inventory positions owned:	39,730			1,515,285			122,679			(313,666		)	1,364,028
	Cash equivalents	101,629			—			—			—			101,629
	Investments at fair value	20,690			—			49,240			—			69,930
	Total assets	$	162,049		$	1,515,285		$	171,919		$	(313,666	)	$	1,535,587
	Liabilities:
	Financial instruments and other inventory positions sold, but not yet purchased:
	Corporate securities:
	Equity securities	$	69,205		$	—		$	—		$	—		$	69,205
	Fixed income securities	—			24,021			—			—			24,021
	U.S. government agency securities	—			120,084			—			—			120,084
	U.S. government securities	291,320			—			—			—			291,320
	Derivative contracts	1,889			324,065			6,643			(324,394		)	8,203
Total financial instruments and other inventory positions sold, but not yet purchased:	$	362,414		$	468,170		$	6,643		$	(324,394	)	$	512,833
-1	Represents cash collateral and the impact of netting on a counterparty basis. The Company had no securities posted as collateral to its counterparties.
Changes in Fair Value Associated with Level III Financial Instruments	'
	The following tables summarize the changes in fair value associated with Level III financial instruments held at the beginning or end of the periods presented:
		Balance at														Realized			Unrealized			Balance at
		March 31,									Transfers			Transfers		gains/			gains/			June 30,
	(Dollars in thousands)	2014			Purchases			Sales			in			out		(losses) (1)			(losses) (1)			2014
	Assets:
	Financial instruments and other inventory positions owned:
	Corporate securities:
	Fixed income securities	$	100		$	—		$	(100	)	$	—		$	—	$	—		$	—		$	—
	Municipal securities:
	Tax-exempt securities	1,433			—			—			—			—		—			(127		)	1,306
	Short-term securities	656			—			(25		)	—			—		6			95			732
	Asset-backed securities	107,399			119,064			(101,878		)	—			—		4,678			(137		)	129,126
	Derivative contracts	64			—			—			—			—		—			563			627
	Total financial instruments and other inventory positions owned:	109,652			119,064			(102,003		)	—			—		4,684			394			131,791
	Investments at fair value	60,954			—			(2,358		)	—			—		2,358			(2,387		)	58,567
	Total assets	$	170,606		$	119,064		$	(104,361	)	$	—		$	—	$	7,042		$	(1,993	)	$	190,358
	Liabilities:
	Financial instruments and other inventory positions sold, but not yet purchased:
	Derivative contracts	$	5,479		$	(8,343	)	$	—		$	—		$	—	$	8,343		$	5,367		$	10,846
	Total financial instruments and other inventory positions sold, but not yet purchased:	$	5,479		$	(8,343	)	$	—		$	—		$	—	$	8,343		$	5,367		$	10,846
	-1	Realized and unrealized gains/(losses) related to financial instruments, with the exception of customer matched-book derivatives, are reported in institutional brokerage on the consolidated statements of operations. Realized and unrealized gains/(losses) related to customer matched-book derivatives are reported in investment banking. Realized and unrealized gains/(losses) related to investments are reported in investment banking revenues or investment income/(loss) on the consolidated statements of operations.
		Balance at														Realized			Unrealized			Balance at
		March 31,									Transfers			Transfers		gains/			gains/			June 30,
	(Dollars in thousands)	2013			Purchases			Sales			in			out		(losses) (1)			(losses) (1)			2013
	Assets:
	Financial instruments and other inventory positions owned:
	Corporate securities:
	Convertible securities	$	—		$	2,559		$	(2,308	)	$	870		$	—	$	9		$	178		$	1,308
	Fixed income securities	—			100			—			—			—		—			—			100
	Municipal securities:
	Tax-exempt securities	1,431			—			—			—			—		—			2			1,433
	Short-term securities	656			—			—			—			—		—			—			656
	Asset-backed securities	107,654			162,754			(123,422		)	—			—		5,573			(1,163		)	151,396
	Derivative contracts	2,372			710			(896		)	—			—		186			15,507			17,879
	Total financial instruments and other inventory positions owned:	112,113			166,123			(126,626		)	870			—		5,768			14,524			172,772
	Investments at fair value	41,653			10,000			—			—			—		—			1,914			53,567
	Total assets	$	153,766		$	176,123		$	(126,626	)	$	870		$	—	$	5,768		$	16,438		$	226,339
	Liabilities:
	Financial instruments and other inventory positions sold, but not yet purchased:
	Derivative contracts	$	399		$	—		$	745		$	—		$	—	$	(745	)	$	(145	)	$	254
	Total financial instruments and other inventory positions sold, but not yet purchased:	$	399		$	—		$	745		$	—		$	—	$	(745	)	$	(145	)	$	254
	-1	Realized and unrealized gains/(losses) related to financial instruments, with the exception of customer matched-book derivatives, are reported in institutional brokerage on the consolidated statements of operations. Realized and unrealized gains/(losses) related to customer matched-book derivatives are reported in investment banking. Realized and unrealized gains/(losses) related to investments are reported in investment banking revenues or investment income/(loss) on the consolidated statements of operations.
	The following tables summarize the changes in fair value associated with Level III financial instruments held at the beginning or end of the periods presented:
		Balance at														Realized			Unrealized			Balance at
		December 31,									Transfers			Transfers		gains/			gains/			June 30,
	(Dollars in thousands)	2013			Purchases			Sales			in			out		(losses) (1)			(losses) (1)			2014
	Assets:
	Financial instruments and other inventory positions owned:
	Corporate securities:
	Fixed income securities	$	100		$	—		$	(100	)	$	—		$	—	$	—		$	—		$	—
	Municipal securities:
	Tax-exempt securities	1,433			—			—			—			—		—			(127		)	1,306
	Short-term securities	656			—			(25		)	—			—		6			95			732
	Asset-backed securities	119,799			151,790			(150,621		)	—			—		9,184			(1,026		)	129,126
	Derivative contracts	691			2,614			—			—			—		(2,614		)	(64		)	627
	Total financial instruments and other inventory positions owned:	122,679			154,404			(150,746		)	—			—		6,576			(1,122		)	131,791
	Investments at fair value	49,240			10,000			(2,358		)	—			—		2,358			(673		)	58,567
	Total assets	$	171,919		$	164,404		$	(153,104	)	$	—		$	—	$	8,934		$	(1,795	)	$	190,358
	Liabilities:
	Financial instruments and other inventory positions sold, but not yet purchased:
	Derivative contracts	$	6,643		$	(16,751	)	$	—		$	—		$	—	$	16,751		$	4,203		$	10,846
	Total financial instruments and other inventory positions sold, but not yet purchased:	$	6,643		$	(16,751	)	$	—		$	—		$	—	$	16,751		$	4,203		$	10,846
	-1	Realized and unrealized gains/(losses) related to financial instruments, with the exception of customer matched-book derivatives, are reported in institutional brokerage on the consolidated statements of operations. Realized and unrealized gains/(losses) related to customer matched-book derivatives are reported in investment banking. Realized and unrealized gains/(losses) related to investments are reported in investment banking revenues or investment income/(loss) on the consolidated statements of operations.
	Balance at														Realized			Unrealized			Balance at
	December 31,									Transfers			Transfers		gains/			gains/			June 30,
(Dollars in thousands)	2012			Purchases			Sales			in			out		(losses) (1)			(losses) (1)			2013
Assets:
Financial instruments and other inventory positions owned:
Corporate securities:
Convertible securities	$	—		$	2,559		$	(2,308	)	$	870		$	—	$	9		$	178		$	1,308
Fixed income securities	—			100			—			—			—		—			—			100
Municipal securities:
Tax-exempt securities	1,429			1			—			—			—		—			3			1,433
Short-term securities	656			—			—			—			—		—			—			656
Asset-backed securities	116,171			196,496			(170,569		)	—			—		16,295			(6,997		)	151,396
Derivative contracts	827			5			(134		)	—			—		43			17,138			17,879
Total financial instruments and other inventory positions owned:	119,083			199,161			(173,011		)	870			—		16,347			10,322			172,772
Investments at fair value	33,245			15,362			—			—			—		4			4,956			53,567
Total assets	$	152,328		$	214,523		$	(173,011	)	$	870		$	—	$	16,351		$	15,278		$	226,339
Liabilities:
Financial instruments and other inventory positions sold, but not yet purchased:
Derivative contracts	$	5,218		$	(5,650	)	$	405		$	—		$	—	$	5,232		$	(4,951	)	$	254
Total financial instruments and other inventory positions sold, but not yet purchased:	$	5,218		$	(5,650	)	$	405		$	—		$	—	$	5,232		$	(4,951	)	$	254
-1	Realized and unrealized gains/(losses) related to financial instruments, with the exception of customer matched-book derivatives, are reported in institutional brokerage on the consolidated statements of operations. Realized and unrealized gains/(losses) related to customer matched-book derivatives are reported in investment banking. Realized and unrealized gains/(losses) related to investments are reported in investment banking revenues or investment income/(loss) on the consolidated statements of operations.

Receivables_from_and_Payables_1

Receivables from and Payables to Brokers, Dealers and Clearing Organizations (Tables)	6 Months Ended
	Jun. 30, 2014
Brokers and Dealers [Abstract]	'
Brokers, Dealers and Clearing Organizations	'
	Amounts receivable from brokers, dealers and clearing organizations included:
		June 30,		December 31,
	(Dollars in thousands)	2014		2013
	Receivable arising from unsettled securities transactions	$	34,030	$	59,657
	Deposits paid for securities borrowed	21,646		36,278
	Receivable from clearing organizations	14,864		966
	Deposits with clearing organizations	51,918		20,995
	Securities failed to deliver	14,504		593
	Other	21,528		8,624
		$	158,490	$	127,113
	Amounts payable to brokers, dealers and clearing organizations included:
		June 30,		December 31,
	(Dollars in thousands)	2014		2013
	Payable arising from unsettled securities transactions	$	206,464	$	5,643
	Payable to clearing organizations	13,088		9,462
	Securities failed to receive	5,491		744
	Other	15,495		11,873
		$	240,538	$	27,722

Collateralized_Securities_Tran1

Collateralized Securities Transactions (Tables)	6 Months Ended
	Jun. 30, 2014
Collateralized Securities Transactions Disclosure [Abstract]	'
Summary of Repurchase Liabilities, Fair Market Value of Related Collateral Pledged and Interest Rate Charged	'
	The following is a summary of the Company’s securities sold under agreements to repurchase ("Repurchase Liabilities"), the fair market value of collateral pledged and the interest rate charged by the Company’s counterparty, which is based on LIBOR plus an applicable margin, as of June 30, 2014:
		Repurchase		Fair Market
	(Dollars in thousands)	Liabilities		Value		Interest Rate
	Term up to 30 day maturities:
	Asset-backed securities	$	11,815	$	15,686	1.66 - 1.75%

Investments_Tables

Investments (Tables)	6 Months Ended
	Jun. 30, 2014
Investments [Abstract]	'
Schedule of Investments	'
	The Company’s proprietary investments include investments in private companies and partnerships, registered mutual funds, warrants of public and private companies and private company debt. Investments included:
		June 30,			December 31,
	(Dollars in thousands)	2014			2013
	Investments at fair value	$	88,486		$	69,930
	Investments at cost	8,271			20,709
	Investments accounted for under the equity method	19,632			21,404
	Total investments	116,389			112,043
	Less investments attributable to noncontrolling interests (1)	(26,263		)	(21,137		)
		$	90,126		$	90,906
	-1	Noncontrolling interests are attributable to third party ownership in a consolidated merchant banking fund and private equity investment vehicles.

Other_Assets_Tables

Other Assets (Tables)	6 Months Ended
	Jun. 30, 2014
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]	'
Other Assets	'
	Other assets included:
		June 30,		December 31,
	(Dollars in thousands)	2014		2013
	Net deferred income tax assets	$	31,310	$	36,252
	Fee receivables	33,306		34,415
	Accrued interest receivables	9,250		9,793
	Forgivable loans, net	9,164		7,879
	Prepaid expenses	5,294		5,237
	Other	10,028		8,516
	Total other assets	$	98,352	$	102,092

Goodwill_and_Intangible_Assets1

Goodwill and Intangible Assets (Tables)	6 Months Ended
	Jun. 30, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Changes in Carrying Value of Goodwill and Intangible Assets	'
	The following table presents the changes in the carrying value of goodwill and intangible assets from continuing operations for the six months ended June 30, 2014:
		Capital			Asset
	(Dollars in thousands)	Markets			Management			Total
	Goodwill
	Balance at December 31, 2013	$	13,790		$	196,844		$	210,634
	Goodwill acquired	—			—			—
	Impairment charge	—			—			—
	Adjustment	1,244			—			1,244
	Balance at June 30, 2014	$	15,034		$	196,844		$	211,878
	Intangible assets
	Balance at December 31, 2013	$	5,316		$	34,614		$	39,930
	Amortization of intangible assets	(1,486		)	(3,150		)	(4,636		)
	Balance at June 30, 2014	$	3,830		$	31,464		$	35,294

ShortTerm_Financing_Tables

Short-Term Financing (Tables)	6 Months Ended
	Jun. 30, 2014
Debt Disclosure [Abstract]	'
Summary of Short-Term Financing and Weighted Average Interest Rate on Borrowings	'
	The following is a summary of short-term financing and the weighted average interest rate on borrowings:
		Outstanding Balance				Weighted Average Interest Rate
		June 30,		December 31,		June 30,		December 31,
	(Dollars in thousands)	2014		2013		2014		2013
	Commercial paper (secured)	$	271,471	$	280,294	1.58	%	1.59	%
	Prime broker arrangement	90,930		234,417		0.91	%	0.9	%
	Total short-term financing	$	362,401	$	514,711

Contingencies_and_Commitments_

Contingencies and Commitments (Tables)	6 Months Ended
	Jun. 30, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block]	'
	The Company leases office space throughout the United States and in a limited number of foreign countries where the Company’s international operations reside. Aggregate minimum lease commitments under operating leases as of June 30, 2014 are as follows:
	(Dollars in thousands)
	Remainder of 2014	$	5,242
	2015	11,957
	2016	11,871
	2017	9,877
	2018	9,563
	Thereafter	35,441
		$	83,951

Noncontrolling_Interests_Table

Noncontrolling Interests (Tables)	6 Months Ended
	Jun. 30, 2014
Noncontrolling Interest [Abstract]	'
Changes in Common Shareholders' Equity Attributable to Parent Company and Equity Attributable to Noncontrolling Interests	'
		Common						Total
		Shareholders’			Noncontrolling			Shareholders’
	(Dollars in thousands)	Equity			Interests			Equity
	Balance at December 31, 2013	$	734,676		$	147,396		$	882,072
	Net income	35,961			7,293			43,254
	Amortization/issuance of restricted stock	20,163			—			20,163
	Issuance of treasury shares for options exercised	1,322			—			1,322
	Repurchase of common stock for employee tax withholding	(8,806		)	—			(8,806		)
	Issuance of treasury shares for 401k match	4,156			—			4,156
	Shares reserved/issued for director compensation	120			—			120
	Other comprehensive income	256			—			256
	Fund capital withdrawals, net	—			(12,780		)	(12,780		)
	Balance at June 30, 2014	$	787,848		$	141,909		$	929,757

Compensation_Plans_Tables

Compensation Plans (Tables)	6 Months Ended
	Jun. 30, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Summary of Outstanding Equity Awards	'
	The following table provides a summary of the Company’s outstanding equity awards (in shares or units) as of June 30, 2014:
	Incentive Plan
	Restricted Stock
	Annual grants	825,343
	Sign-on grants	346,055
		1,171,398
	Inducement Plan
	Restricted Stock	29,159
	Total restricted stock related to compensation	1,200,557
	ARI deal consideration (1)	104,496
	Total restricted stock outstanding	1,305,053
	Incentive Plan
	Restricted Stock Units
	Leadership grants	405,826
	Incentive Plan
	Stock options outstanding	321,490
	-1	The Company issued restricted stock as part of deal consideration in conjunction with the acquisition of ARI.
Schedule of Valuation Assumptions	'
	The fair value of the awards on the grant date were determined using a Monte Carlo simulation with the following assumptions:
			Risk-free	Expected Stock
	Grant Year		Interest Rate	Price Volatility
	2014		0.82%	41.30%
	2013		0.40%	44.00%
	2012		0.38%	47.60%
Changes in Unvested Restricted Stock	'
	The following table summarizes the changes in the Company’s unvested restricted stock (including the unvested restricted stock issued as part of the deal consideration for ARI) under the Incentive Plan and Inducement Plan for the six months ended June 30, 2014:
		Unvested		Weighted Average
		Restricted Stock		Grant Date
		(in Shares)		Fair Value
	December 31, 2013	1,582,062		$	35.25
	Granted	404,474		40.13
	Vested	(675,940	)	35.99
	Canceled	(5,543	)	33.72
	June 30, 2014	1,305,053		$	36.39
Changes in Unvested Restricted Stock Units	'
	The following summarizes the changes in the Company’s unvested restricted stock units under the Incentive Plan for the six months ended June 30, 2014:
		Unvested		Weighted Average
		Restricted		Grant Date
		Stock Units		Fair Value
	December 31, 2013	290,536		$	15.83
	Granted	115,290		23.42
	Vested	—		—
	Canceled	—		—
	June 30, 2014	405,826		$	17.99
Changes in Outstanding Stock Options	'
	The following table summarizes the changes in the Company’s outstanding stock options for the six months ended June 30, 2014:
						Weighted Average
				Weighted		Remaining
		Options		Average		Contractual Term	Aggregate
		Outstanding		Exercise Price		(in Years)	Intrinsic Value
	December 31, 2013	469,289		$	44.83	2	$	288,318
	Granted	—		—
	Exercised	(34,247	)	35.75
	Canceled	(55	)	39.62
	Expired	(113,497	)	47.72
	June 30, 2014	321,490		$	44.78	2.2	$	3,125,267
	Options exercisable at June 30, 2014	321,490		$	44.78	2.2	$	3,125,267

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	6 Months Ended
	Jun. 30, 2014
Earnings Per Share [Abstract]	'
Computation of Earnings per Share	'
	The computation of earnings per share is as follows:
		Three Months Ended						Six Months Ended
		June 30,						June 30,
	(Amounts in thousands, except per share data)	2014			2013			2014			2013
	Net income from continuing operations applicable to Piper Jaffray Companies	$	18,213		$	4,359		$	35,961		$	15,026
	Net loss from discontinued operations	—			(1,871		)	—			(2,392		)
	Net income applicable to Piper Jaffray Companies	18,213			2,488			35,961			12,634
	Earnings allocated to participating securities (1)	(1,496		)	(222		)	(3,155		)	(1,301		)
	Net income applicable to Piper Jaffray Companies’ common shareholders (2)	$	16,717		$	2,266		$	32,806		$	11,333
	Shares for basic and diluted calculations:
	Average shares used in basic computation	14,958			15,621			14,786			15,602
	Stock options	55			5			50			17
	Average shares used in diluted computation	15,013			15,626			14,836			15,619
	Earnings/(loss) per basic common share:
	Income from continuing operations	$	1.12		$	0.25		$	2.22		$	0.86
	Loss from discontinued operations	—			(0.11		)	—			(0.14		)
	Earnings per basic common share	$	1.12		$	0.15		$	2.22		$	0.73
	Earnings/(loss) per diluted common share:
	Income from continuing operations	$	1.11		$	0.25		$	2.21		$	0.86
	Loss from discontinued operations	—			(0.11		)	—			(0.14		)
	Earnings per diluted common share	$	1.11		$	0.15		$	2.21		$	0.73
	-1	Represents the allocation of earnings to participating securities. Losses are not allocated to participating securities. Participating securities include all of the Company’s unvested restricted shares. The weighted average participating shares outstanding were 1,343,399 and 1,531,100 for the three months ended June 30, 2014 and 2013, respectively, and 1,426,656 and 1,791,940 for the six months ended June 30, 2014 and 2013, respectively.
	-2	Net income/(loss) applicable to Piper Jaffray Companies’ common shareholders for diluted and basic EPS may differ under the two-class method as a result of adding the effect of the assumed exercise of stock options to dilutive shares outstanding, which alters the ratio used to allocate earnings to Piper Jaffray Companies’ common shareholders and participating securities for purposes of calculating diluted and basic EPS.

Segment_Reporting_Tables

Segment Reporting (Tables)	6 Months Ended
	Jun. 30, 2014
Segment Reporting [Abstract]	'
Reportable Segment Financial Results	'
	Reportable segment financial results from continuing operations are as follows:
		Three Months Ended						Six Months Ended
		June 30,						June 30,
	(Dollars in thousands)	2014			2013			2014			2013
	Capital Markets
	Investment banking
	Financing
	Equities	$	44,058		$	21,772		$	79,359		$	36,075
	Debt	20,174			22,131			33,713			39,163
	Advisory services	39,695			9,394			79,423			18,950
	Total investment banking	103,927			53,297			192,495			94,188
	Institutional sales and trading
	Equities	18,366			21,384			42,626			42,119
	Fixed income	21,085			8,261			46,323			32,649
	Total institutional sales and trading	39,451			29,645			88,949			74,768
	Management and performance fees	1,388			564			3,125			1,583
	Investment income	4,998			184			15,376			6,321
	Long-term financing expenses	(1,705		)	(1,872		)	(3,445		)	(3,821		)
	Net revenues	148,059			81,818			296,500			173,039
	Operating expenses (1)	124,691			83,937			245,621			162,395
	Segment pre-tax operating income/(loss)	$	23,368		$	(2,119	)	$	50,879		$	10,644
	Segment pre-tax operating margin	15.8		%	(2.6		)%	17.2		%	6.2		%
		Three Months Ended						Six Months Ended
		June 30,						June 30,
	(Dollars in thousands)	2014			2013			2014			2013
	Asset Management
	Management and performance fees
	Management fees	$	20,600		$	17,558		$	39,736		$	34,644
	Performance fees	278			305			364			656
	Total management and performance fees	20,878			17,863			40,100			35,300
	Investment income	1,094			91			1,564			966
	Net revenues	21,972			17,954			41,664			36,266
	Operating expenses (1)	14,923			12,502			29,413			25,409
	Segment pre-tax operating income	$	7,049		$	5,452		$	12,251		$	10,857
	Segment pre-tax operating margin	32.1		%	30.4		%	29.4		%	29.9		%
	Total
	Net revenues	$	170,031		$	99,772		$	338,164		$	209,305
	Operating expenses (1)	139,614			96,439			275,034			187,804
	Pre-tax operating income	$	30,417		$	3,333		$	63,130		$	21,501
	Pre-tax operating margin	17.9		%	3.3		%	18.7		%	10.3		%
	-1	Operating expenses include intangible asset amortization expense as set forth in the table below:
		Three Months Ended						Six Months Ended
		June 30,						June 30,
	(Dollars in thousands)	2014			2013			2014			2013
	Capital Markets	$	743		$	—		$	1,486		$	—
	Asset Management	1,575			1,661			3,150			3,322
	Total intangible asset amortization expense	$	2,318		$	1,661		$	4,636		$	3,322
Schedule of Intangible Asset Amortization Expense	'
	Operating expenses include intangible asset amortization expense as set forth in the table below:
		Three Months Ended						Six Months Ended
		June 30,						June 30,
	(Dollars in thousands)	2014			2013			2014			2013
	Capital Markets	$	743		$	—		$	1,486		$	—
	Asset Management	1,575			1,661			3,150			3,322
	Total intangible asset amortization expense	$	2,318		$	1,661		$	4,636		$	3,322
Net Revenues by Geographic Locations	'
	Net revenues exclude discontinued operations for all periods presented.
		Three Months Ended						Six Months Ended
		June 30,						June 30,
	(Dollars in thousands)	2014			2013			2014			2013
	Net revenues:
	United States	$	167,552		$	97,195		$	332,876		$	202,921
	Europe	2,479			2,577			5,288			6,384
	Consolidated	$	170,031		$	99,772		$	338,164		$	209,305
Long-Lived Assets by Geographic Region	'
	Long-lived assets are allocated to geographic locations based upon the location of the asset. The following table presents long-lived assets by geographic region:
		June 30,			December 31,
	(Dollars in thousands)	2014			2013
	Long-lived assets:
	United States	$	287,737		$	296,516
	Europe	6,396			6,414
	Consolidated	$	294,133		$	302,930

Organization_and_Basis_of_Pres1

Organization and Basis of Presentation - Additional Information (Detail) (USD $)	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2013	Jun. 30, 2013	Jun. 30, 2013
	segment	Interest Revenue [Member]	Interest Revenue [Member]	Interest Expense [Member]	Interest Expense [Member]
Organization, Consolidation and Presentation of Financial Statements [Line Items]	'	'	'	'	'
Number of reportable segments	2	'	'	'	'
Reclassified amount	'	$2.10	$4.60	($2.60)	($5.40)

Acquisitions_Additional_Inform

Acquisitions - Additional Information(Details) (USD $)	6 Months Ended	0 Months Ended			0 Months Ended
	Jun. 30, 2014	Jul. 16, 2013	Jul. 16, 2013	Jul. 16, 2013	Jul. 16, 2013	Jul. 16, 2013	Jul. 16, 2013
		Seattle-Northwest Securities Corporation and Edgeview Partners, L.P.	Seattle-Northwest Securities Corporation and Edgeview Partners, L.P.	Seattle-Northwest Securities Corporation and Edgeview Partners, L.P.	Seattle-Northwest Securities Corporation and Edgeview Partners, L.P.	Seattle-Northwest Securities Corporation and Edgeview Partners, L.P.	Seattle-Northwest Securities Corporation and Edgeview Partners, L.P.
			Customer Relationships	Noncompete Agreements	Minimum	Maximum	Weighted Average
Business Acquisition [Line Items]	'	'	'	'	'	'	'
Consideration transferred	'	$32,700,000	'	'	'	'	'
Acquisition related compensation arrangements	'	14,300,000	'	'	'	'	'
Acquisition related compensation arrangement award vesting period	'	'	'	'	'2 years	'5 years	'4 years 3 months
Goodwill acquired	'	15,000,000	'	'	'	'	'
Goodwill amount expected to be deducted for income tax purposes	'	9,100,000	'	'	'	'	'
Intangible assets	'	6,665,000	6,000,000	700,000	'	'	'
Goodwill measurement period adjustment	$1,244,000	'	'	'	'	'	'

Acquisitions_Estimated_Fair_Va

Acquisitions - Estimated Fair Values of Assets Acquired and Liabilities Assumed (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013	Jul. 16, 2013
In Thousands, unless otherwise specified			Seattle-Northwest Securities Corporation and Edgeview Partners, L.P.
Assets	'	'	'
Cash and cash equivalents	'	'	$8,014
Financial instruments and other inventory positions owned	'	'	24,074
Fixed assets	'	'	1,247
Goodwill	211,878	210,634	15,034
Intangible assets	'	'	6,665
Other assets	'	'	7,678
Total assets acquired	'	'	62,712
Liabilities	'	'	'
Payables	'	'	1,126
Financial instruments and other inventory positions sold, but not yet purchased	'	'	22,588
Accrued compensation	'	'	1,469
Other liabilities and accrued expenses	'	'	4,789
Total liabilities assumed	'	'	29,972
Net assets acquired	'	'	$32,740

Acquisitions_Unaudited_Pro_For

Acquisitions - Unaudited Pro Forma Information (Details) (USD $)	3 Months Ended	6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2013	Jun. 30, 2013
Business Combinations [Abstract]	'	'
Net revenues	$107,415	$220,955
Net income from continuing operations applicable to Piper Jaffray Companies	$4,260	$13,356

Discontinued_Operations_Detail

Discontinued Operations (Details Textual) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]	'	'	'	'
Loss from discontinued operations, net of tax	$0	($1,871,000)	$0	($2,392,000)
FAMCO	'	'	'	'
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]	'	'	'	'
Sale of FAMCO, sale price	'	4,000,000	'	4,000,000
Sale of FAMCO, cash proceeds	'	300,000	'	'
Sale of FAMCO, note receivable received	'	3,700,000	'	'
FAMCO | Other Liabilities and Accrued Expenses	'	'	'	'
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]	'	'	'	'
Sale of FAMCO, indemnification accrual	$400,000	'	$400,000	'

Financial_Instruments_and_Othe2

Financial Instruments and Other Inventory Positions Owned and Financial Instruments and Other Inventory Positions Sold, but Not Yet Purchased (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]	'	'
Total financial instruments and other inventory positions owned	$1,469,071	$1,364,028
Financial instruments and other inventory positions owned, attributable to noncontrolling interest	-251,519	-291,513
Financial instruments and other inventory positions owned, attributable to parent	1,217,552	1,072,515
Financial instruments and other inventory positions sold, but not yet purchased	518,286	512,833
Financial instruments and other inventory positions owned and pledged as collateral	899,375	957,515
Fair Value, Disclosure Item Amounts [Domain]	'	'
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]	'	'
Financial instruments and other inventory positions owned and pledged as collateral, attributable to parent	431,199	444,477
Equity securities	'	'
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]	'	'
Total financial instruments and other inventory positions owned	55,975	54,097
Financial instruments and other inventory positions sold, but not yet purchased	96,962	69,205
Convertible securities	'	'
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]	'	'
Total financial instruments and other inventory positions owned	94,496	80,784
Fixed income securities	'	'
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]	'	'
Total financial instruments and other inventory positions owned	27,344	10,102
Financial instruments and other inventory positions sold, but not yet purchased	9,974	24,021
Taxable securities	'	'
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]	'	'
Total financial instruments and other inventory positions owned	237,126	232,379
Financial instruments and other inventory positions owned, attributable to noncontrolling interest	-109,700	-101,800
Tax-exempt securities	'	'
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]	'	'
Total financial instruments and other inventory positions owned	467,537	460,865
Financial instruments and other inventory positions owned, attributable to noncontrolling interest	-137,100	-183,900
Short-term securities	'	'
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]	'	'
Total financial instruments and other inventory positions owned	152,209	62,620
Asset-backed securities	'	'
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]	'	'
Total financial instruments and other inventory positions owned	133,719	119,811
U.S. government agency securities	'	'
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]	'	'
Total financial instruments and other inventory positions owned	245,365	304,737
Financial instruments and other inventory positions sold, but not yet purchased	49,009	120,084
U.S. government securities	'	'
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]	'	'
Total financial instruments and other inventory positions owned	8,185	0
Financial instruments and other inventory positions sold, but not yet purchased	345,756	291,320
Financial instruments and other inventory positions owned and pledged as collateral, attributable to noncontrolling interest	-85,500	-67,400
Derivative contracts	'	'
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]	'	'
Total financial instruments and other inventory positions owned	47,115	38,633
Financial instruments and other inventory positions owned, attributable to noncontrolling interest	-4,800	-5,800
Financial instruments and other inventory positions sold, but not yet purchased	16,585	8,203
Financial instruments and other inventory positions owned and pledged as collateral, attributable to noncontrolling interest	-1,600	-1,000
Non-Controlling interests financial instruments [Member]	'	'
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]	'	'
Financial instruments and other inventory positions owned and pledged as collateral, attributable to noncontrolling interest	($87,087)	($68,356)

Financial_Instruments_and_Othe3

Financial Instruments and Other Inventory Positions Owned and Financial Instruments and Other Inventory Positions Sold, but Not Yet Purchased - Total Absolute Notional Contract Amount (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Derivative [Line Items]	'	'
Absolute Notional Contract Amount of Derivative Instruments	$5,802,693	$5,825,852
Customer matched-book | Interest rate derivative contract	'	'
Derivative [Line Items]	'	'
Absolute Notional Contract Amount of Derivative Instruments	5,103,320	5,310,929
Trading securities | Interest rate derivative contract	'	'
Derivative [Line Items]	'	'
Absolute Notional Contract Amount of Derivative Instruments	225,500	198,500
Trading securities | Credit default swap index contract	'	'
Derivative [Line Items]	'	'
Absolute Notional Contract Amount of Derivative Instruments	457,904	299,333
Trading securities | Equity Option [Member]	'	'
Derivative [Line Items]	'	'
Absolute Notional Contract Amount of Derivative Instruments	$15,969	$17,090

Financial_Instruments_and_Othe4

Financial Instruments and Other Inventory Positions Owned and Financial Instruments and Other Inventory Positions Sold, but Not Yet Purchased - Unrealized Gains/(Losses) on Derivative Instruments (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Derivative [Line Items]	'	'	'	'
Unrealized Gain (Loss) on Derivatives Instruments	($8,008)	$18,559	($8,138)	$22,081
Interest rate derivative contract | Investment banking	'	'	'	'
Derivative [Line Items]	'	'	'	'
Unrealized Gain (Loss) on Derivatives Instruments	-844	-111	-1,369	-649
Interest rate derivative contract | Institutional brokerage	'	'	'	'
Derivative [Line Items]	'	'	'	'
Unrealized Gain (Loss) on Derivatives Instruments	-4,798	15,527	-4,266	21,462
Credit default swap index contract | Institutional brokerage	'	'	'	'
Derivative [Line Items]	'	'	'	'
Unrealized Gain (Loss) on Derivatives Instruments	-1,668	3,143	-2,922	1,268
Equity Option Derivative Contract [Member] | Institutional brokerage	'	'	'	'
Derivative [Line Items]	'	'	'	'
Unrealized Gain (Loss) on Derivatives Instruments	($698)	$0	$419	$0

Financial_Instruments_and_Othe5

Financial Instruments and Other Inventory Positions Owned and Financial Instruments and Other Inventory Positions Sold, but Not Yet Purchased - Gross Fair Market Value of Derivative Instruments (Details) (USD $)	Jun. 30, 2014
In Thousands, unless otherwise specified
Derivative [Line Items]	'
Fair value of derivative assets, gross	$415,037
Fair value of derivative liabilities, gross	406,924
Financial instruments and other inventory positions owned | Interest rate derivative contract	'
Derivative [Line Items]	'
Fair value of derivative assets, gross	407,298
Financial instruments and other inventory positions owned | Credit default swap index contract	'
Derivative [Line Items]	'
Fair value of derivative assets, gross	7,645
Financial instruments and other inventory positions owned | Equity Option [Member]	'
Derivative [Line Items]	'
Fair value of derivative assets, gross	94
Financial instruments and other inventory positions sold, but not yet purchased | Interest rate derivative contract	'
Derivative [Line Items]	'
Fair value of derivative liabilities, gross	393,755
Financial instruments and other inventory positions sold, but not yet purchased | Credit default swap index contract	'
Derivative [Line Items]	'
Fair value of derivative liabilities, gross	11,790
Financial instruments and other inventory positions sold, but not yet purchased | Equity Option [Member]	'
Derivative [Line Items]	'
Fair value of derivative liabilities, gross	$1,379

Financial_Instruments_and_Othe6

Financial Instruments and Other Inventory Positions Owned and Financial Instruments and Other Inventory Positions Sold, but Not Yet Purchased - Additional Information (Details) (USD $)	Jun. 30, 2014
In Millions, unless otherwise specified
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]	'
Uncollateralized credit exposure	$25.50
Notional contract amount of derivatives with counterparties not required to post collateral	199.5
Counterparty	'
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]	'
Uncollateralized credit exposure	$12.90

Fair_Value_of_Financial_Instru2

Fair Value of Financial Instruments - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'
Investments at fair value	$88,486,000	'	$88,486,000	'	$69,930,000
Gains from fair value changes	'	'	1,000,000	5,500,000	'
Total assets	1,558,875,000	'	1,558,875,000	'	1,535,587,000
Transfers of financial assets from Level III	'	'	'	'	'
Goodwill impairment	'	'	'	'	'
Transfers between fair value levels	'	'	0	'	'
Level III	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'
Investments at fair value	58,567,000	'	58,567,000	'	49,240,000
Total assets	190,358,000	'	190,358,000	'	171,919,000
Percentage of Level III assets to financial instruments measured at fair value	12.20%	'	12.20%	'	11.20%
Minimum | U.S. government agency securities	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'
Market yields basis points spreads to treasury securities (as a percent)	0.18%	'	0.18%	'	'
Prepayment expectations based upon PSA prepayment levels	47	'	47	'	'
Maximum | U.S. government agency securities	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'
Market yields basis points spreads to treasury securities (as a percent)	5.11%	'	5.11%	'	'
Prepayment expectations based upon PSA prepayment levels	328	'	328	'	'
Merchant Banking Investments | Merchant Banking Investments	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'
Investments at fair value	$16,800,000	'	$16,800,000	'	$16,100,000

Fair_Value_of_Financial_Instru3

Fair Value of Financial Instruments - Information about Significant Unobservable Inputs used in Fair Value Measurement (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2012
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	$190,358	$226,339	$190,358	$226,339	$170,606	$171,919	$153,766	$152,328
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	119,064	176,123	164,404	214,523	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	104,361	126,626	153,104	173,011	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	'	870	'	870	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	'	'	'	'	'	'	'	'
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Realized Gain Loss Included In Earnings	7,042	5,768	8,934	16,351	'	'	'	'
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Unrealized Gain Loss Included In Earnings	-1,993	16,438	-1,795	15,278	'	'	'	'
Minimum	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Fair Value Inputs, Earnings before Interest, Taxes, Depreciation, and Amortization Multiple	'	'	8.8	'	'	'	'	'
Minimum | U.S. government agency securities	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Market Yields Basis Point	0.18%	'	0.18%	'	'	'	'	'
Maximum	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Fair Value Inputs, Earnings before Interest, Taxes, Depreciation, and Amortization Multiple	'	'	12	'	'	'	'	'
Maximum | U.S. government agency securities	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Market Yields Basis Point	5.11%	'	5.11%	'	'	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased | Minimum | Discounted cash flow | Level III | Interest rate derivative contract	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Unamortized premium over the MMD curve	'	'	0.00%	'	'	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased | Maximum | Discounted cash flow | Level III | Interest rate derivative contract	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Unamortized premium over the MMD curve	'	'	0.34%	'	'	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased | Weighted Average | Discounted cash flow | Level III | Interest rate derivative contract	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Unamortized premium over the MMD curve	'	'	0.14%	'	'	'	'	'
Financial instruments and other inventory positions owned	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	131,791	172,772	131,791	172,772	109,652	122,679	112,113	119,083
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	119,064	166,123	154,404	199,161	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	102,003	126,626	150,746	173,011	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	'	870	'	870	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	'	'	'	'	'	'	'	'
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Realized Gain Loss Included In Earnings	4,684	5,768	6,576	16,347	'	'	'	'
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Unrealized Gain Loss Included In Earnings	394	14,524	-1,122	10,322	'	'	'	'
Financial instruments and other inventory positions owned | Convertible securities	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	'	1,308	'	1,308	'	'	0	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	'	2,559	'	2,559	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	'	2,308	'	2,308	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	'	870	'	870	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	'	0	'	'	'	'	'	'
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Realized Gain Loss Included In Earnings	'	9	'	9	'	'	'	'
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Unrealized Gain Loss Included In Earnings	'	178	'	178	'	'	'	'
Financial instruments and other inventory positions owned | Tax-exempt securities	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	1,306	1,433	1,306	1,433	1,433	1,433	1,431	1,429
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	'	'	'	1	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	'	'	'	'	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	'	'	'	'	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	'	'	'	'	'	'	'	'
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Realized Gain Loss Included In Earnings	'	'	'	'	'	'	'	'
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Unrealized Gain Loss Included In Earnings	-127	2	-127	3	'	'	'	'
Financial instruments and other inventory positions owned | Short-term securities	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	732	656	732	656	656	656	656	656
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	'	'	'	'	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	25	'	25	'	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	'	'	'	'	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	'	'	'	'	'	'	'	'
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Realized Gain Loss Included In Earnings	6	'	6	'	'	'	'	'
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Unrealized Gain Loss Included In Earnings	95	'	95	'	'	'	'	'
Financial instruments and other inventory positions owned | Asset-backed securities	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	129,126	151,396	129,126	151,396	107,399	119,799	107,654	116,171
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	119,064	162,754	151,790	196,496	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	101,878	123,422	150,621	170,569	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	'	'	'	'	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	'	'	'	'	'	'	'	'
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Realized Gain Loss Included In Earnings	4,678	5,573	9,184	16,295	'	'	'	'
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Unrealized Gain Loss Included In Earnings	($137)	($1,163)	($1,026)	($6,997)	'	'	'	'
Financial instruments and other inventory positions owned | Minimum | Discounted cash flow | Level III | Tax-exempt securities	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Debt service coverage ratio	'	'	5.00%	'	'	'	'	'
Financial instruments and other inventory positions owned | Minimum | Discounted cash flow | Level III | Short-term securities	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Expected recovery rate (% of par)	'	'	77.00%	'	'	'	'	'
Financial instruments and other inventory positions owned | Minimum | Discounted cash flow | Level III | Collateralized by Residential mortgages	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Credit default rate	'	'	0.00%	'	'	'	'	'
Prepayment rates	'	'	1.00%	'	'	'	'	'
Loss severity	'	'	50.00%	'	'	'	'	'
Valuation yields	'	'	3.00%	'	'	'	'	'
Financial instruments and other inventory positions owned | Minimum | Discounted cash flow | Level III | Interest rate derivative contract	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Unamortized premium over the MMD curve	'	'	0.27%	'	'	'	'	'
Financial instruments and other inventory positions owned | Minimum | Black-Scholes option pricing model | Level III | Warrants in public and private companies	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Liquidity discount rates	'	'	30.00%	'	'	'	'	'
Financial instruments and other inventory positions owned | Minimum | Black-Scholes option pricing model | Level III | Warrants in private companies	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Stock volatility factors of comparable companies	'	'	21.80%	'	'	'	'	'
Financial instruments and other inventory positions owned | Minimum | Market Comparable | Level III | Equity investment in private company	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Revenue multiple	'	'	1.7	'	'	'	'	'
Financial instruments and other inventory positions owned | Maximum | Discounted cash flow | Level III | Tax-exempt securities	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Debt service coverage ratio	'	'	69.00%	'	'	'	'	'
Financial instruments and other inventory positions owned | Maximum | Discounted cash flow | Level III | Short-term securities	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Expected recovery rate (% of par)	'	'	80.00%	'	'	'	'	'
Financial instruments and other inventory positions owned | Maximum | Discounted cash flow | Level III | Collateralized by Residential mortgages	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Credit default rate	'	'	10.00%	'	'	'	'	'
Prepayment rates	'	'	15.00%	'	'	'	'	'
Loss severity	'	'	100.00%	'	'	'	'	'
Valuation yields	'	'	8.00%	'	'	'	'	'
Financial instruments and other inventory positions owned | Maximum | Discounted cash flow | Level III | Interest rate derivative contract	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Unamortized premium over the MMD curve	'	'	0.41%	'	'	'	'	'
Financial instruments and other inventory positions owned | Maximum | Discounted cash flow | Level III | Equity investment in private company	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Revenue multiple	'	'	6.7	'	'	'	'	'
Financial instruments and other inventory positions owned | Maximum | Black-Scholes option pricing model | Level III | Warrants in public and private companies	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Liquidity discount rates	'	'	40.00%	'	'	'	'	'
Financial instruments and other inventory positions owned | Maximum | Black-Scholes option pricing model | Level III | Warrants in private companies	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Stock volatility factors of comparable companies	'	'	85.10%	'	'	'	'	'
Financial instruments and other inventory positions owned | Weighted Average | Discounted cash flow | Level III | Tax-exempt securities	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Debt service coverage ratio	'	'	22.20%	'	'	'	'	'
Financial instruments and other inventory positions owned | Weighted Average | Discounted cash flow | Level III | Short-term securities	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Expected recovery rate (% of par)	'	'	79.60%	'	'	'	'	'
Financial instruments and other inventory positions owned | Weighted Average | Discounted cash flow | Level III | Collateralized by Residential mortgages	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Credit default rate	'	'	3.60%	'	'	'	'	'
Prepayment rates	'	'	4.30%	'	'	'	'	'
Loss severity	'	'	58.30%	'	'	'	'	'
Valuation yields	'	'	4.80%	'	'	'	'	'
Financial instruments and other inventory positions owned | Weighted Average | Discounted cash flow | Level III | Interest rate derivative contract	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Unamortized premium over the MMD curve	'	'	0.39%	'	'	'	'	'
Financial instruments and other inventory positions owned | Weighted Average | Discounted cash flow | Level III | Equity investment in private company	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Revenue multiple	'	'	3.7	'	'	'	'	'
Fair Value Inputs, Earnings before Interest, Taxes, Depreciation, and Amortization Multiple	'	'	9.3	'	'	'	'	'
Financial instruments and other inventory positions owned | Weighted Average | Black-Scholes option pricing model | Level III | Warrants in public and private companies	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Liquidity discount rates	'	'	34.30%	'	'	'	'	'
Financial instruments and other inventory positions owned | Weighted Average | Black-Scholes option pricing model | Level III | Warrants in private companies	'	'	'	'	'	'	'	'
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]	'	'	'	'	'	'	'	'
Stock volatility factors of comparable companies	'	'	40.60%	'	'	'	'	'

Fair_Value_of_Financial_Instru4

Fair Value of Financial Instruments - Valuation of Financial Instruments by Pricing Observability Levels (Details) (USD $)	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	$1,469,071	'	$1,364,028	'	'	'
Cash equivalents	1,318	'	101,629	'	'	'
Investments at fair value	88,486	'	69,930	'	'	'
Total assets	1,558,875	'	1,535,587	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	518,286	'	512,833	'	'	'
Equity securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	55,975	'	54,097	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	96,962	'	69,205	'	'	'
Convertible securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	94,496	'	80,784	'	'	'
Fixed income securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	27,344	'	10,102	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	9,974	'	24,021	'	'	'
Taxable securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	237,126	'	232,379	'	'	'
Tax-exempt securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	467,537	'	460,865	'	'	'
Short-term securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	152,209	'	62,620	'	'	'
Asset-backed securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	133,719	'	119,811	'	'	'
U.S. government agency securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	245,365	'	304,737	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	49,009	'	120,084	'	'	'
U.S. government securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	8,185	'	0	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	345,756	'	291,320	'	'	'
Derivative contracts	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	47,115	'	38,633	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	16,585	'	8,203	'	'	'
Level I	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	44,992	'	39,730	'	'	'
Cash equivalents	1,318	'	101,629	'	'	'
Investments at fair value	29,919	'	20,690	'	'	'
Total assets	76,229	'	162,049	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	443,868	'	362,414	'	'	'
Level I | Equity securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	36,713	'	39,711	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	96,733	'	69,205	'	'	'
Level I | Convertible securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Level I | Fixed income securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	'	'	'	'	'	'
Level I | Taxable securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Level I | Tax-exempt securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Level I | Short-term securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Level I | Asset-backed securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Level I | U.S. government agency securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	'	'	'	'	'	'
Level I | U.S. government securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	8,185	'	'	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	345,756	'	291,320	'	'	'
Level I | Derivative contracts	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	94	'	19	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	1,379	'	1,889	'	'	'
Level II	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	1,660,210	'	1,515,285	'	'	'
Cash equivalents	'	'	'	'	'	'
Investments at fair value	'	'	'	'	'	'
Total assets	1,660,210	'	1,515,285	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	453,911	'	468,170	'	'	'
Level II | Equity securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	19,262	'	14,386	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	229	'	'	'	'	'
Level II | Convertible securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	94,496	'	80,784	'	'	'
Level II | Fixed income securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	27,344	'	10,002	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	9,974	'	24,021	'	'	'
Level II | Taxable securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	237,126	'	232,379	'	'	'
Level II | Tax-exempt securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	466,231	'	459,432	'	'	'
Level II | Short-term securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	151,477	'	61,964	'	'	'
Level II | Asset-backed securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	4,593	'	12	'	'	'
Level II | U.S. government agency securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	245,365	'	304,737	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	49,009	'	120,084	'	'	'
Level II | U.S. government securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	'	'	'	'	'	'
Level II | Derivative contracts	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	414,316	'	351,589	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	394,699	'	324,065	'	'	'
Level III	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	131,791	'	122,679	'	'	'
Cash equivalents	'	'	'	'	'	'
Investments at fair value	58,567	'	49,240	'	'	'
Total assets	190,358	'	171,919	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	10,846	'	6,643	'	'	'
Level III | Equity securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	'	'	'	'	'	'
Level III | Convertible securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Level III | Fixed income securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	100	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	'	'	'	'	'	'
Level III | Taxable securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Level III | Tax-exempt securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	1,306	'	1,433	'	'	'
Level III | Short-term securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	732	'	656	'	'	'
Level III | Asset-backed securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	129,126	'	119,799	'	'	'
Level III | U.S. government agency securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	'	'	'	'	'	'
Level III | U.S. government securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	'	'	'	'	'	'
Level III | Derivative contracts	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	627	'	691	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	10,846	'	6,643	'	'	'
Counterparty and Cash Collateral Netting	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	-367,922	'	-313,666	'	'	'
Cash equivalents	'	'	'	'	'	'
Investments at fair value	'	'	'	'	'	'
Total assets	-367,922	'	-313,666	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	-390,339	'	-324,394	'	'	'
Counterparty and Cash Collateral Netting | Equity securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	'	'	'	'	'	'
Counterparty and Cash Collateral Netting | Convertible securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Counterparty and Cash Collateral Netting | Fixed income securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	'	'	'	'	'	'
Counterparty and Cash Collateral Netting | Taxable securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Counterparty and Cash Collateral Netting | Tax-exempt securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Counterparty and Cash Collateral Netting | Short-term securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Counterparty and Cash Collateral Netting | Asset-backed securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Counterparty and Cash Collateral Netting | U.S. government agency securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	'	'	'	'	'	'
Counterparty and Cash Collateral Netting | U.S. government securities	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	'	'	'	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	'	'	'	'	'	'
Counterparty and Cash Collateral Netting | Derivative contracts	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Total financial instruments and other inventory positions owned	-367,922	'	-313,666	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	-390,339	'	-324,394	'	'	'
Financial instruments and other inventory positions sold, but not yet purchased	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	10,846	5,479	6,643	254	399	5,218
Financial instruments and other inventory positions sold, but not yet purchased | Derivative contracts	'	'	'	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	$10,846	$5,479	$6,643	$254	$399	$5,218

Fair_Value_of_Financial_Instru5

Fair Value of Financial Instruments - Changes in Fair Value Associated with Level III Financial Instruments (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]	'	'	'	'
Transfers between fair value levels	'	'	$0	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'	'	'
Beginning balance	170,606,000	153,766,000	171,919,000	152,328,000
Purchases	119,064,000	176,123,000	164,404,000	214,523,000
Sales	-104,361,000	-126,626,000	-153,104,000	-173,011,000
Transfers in	'	870,000	'	870,000
Transfers out	'	'	'	'
Realized gains/ (losses)	7,042,000	5,768,000	8,934,000	16,351,000
Unrealized gains/ (losses)	-1,993,000	16,438,000	-1,795,000	15,278,000
Ending balance	190,358,000	226,339,000	190,358,000	226,339,000
Financial instruments and other inventory positions sold, but not yet purchased	'	'	'	'
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'	'	'
Beginning balance	5,479,000	399,000	6,643,000	5,218,000
Purchases	-8,343,000	'	-16,751,000	-5,650,000
Sales	'	745,000	'	405,000
Transfers in	'	'	'	'
Transfers out	'	'	'	'
Realized gains/(losses)	8,343,000	-745,000	16,751,000	5,232,000
Unrealized gains/ (losses)	5,367,000	-145,000	4,203,000	-4,951,000
Ending balance	10,846,000	254,000	10,846,000	254,000
Financial instruments and other inventory positions sold, but not yet purchased | Derivative contracts	'	'	'	'
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'	'	'
Beginning balance	5,479,000	399,000	6,643,000	5,218,000
Purchases	-8,343,000	'	-16,751,000	-5,650,000
Sales	'	745,000	'	405,000
Transfers in	'	'	'	'
Transfers out	'	'	'	'
Realized gains/(losses)	8,343,000	-745,000	16,751,000	5,232,000
Unrealized gains/ (losses)	5,367,000	-145,000	4,203,000	-4,951,000
Ending balance	10,846,000	254,000	10,846,000	254,000
Financial instruments and other inventory positions owned	'	'	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'	'	'
Beginning balance	109,652,000	112,113,000	122,679,000	119,083,000
Purchases	119,064,000	166,123,000	154,404,000	199,161,000
Sales	-102,003,000	-126,626,000	-150,746,000	-173,011,000
Transfers in	'	870,000	'	870,000
Transfers out	'	'	'	'
Realized gains/ (losses)	4,684,000	5,768,000	6,576,000	16,347,000
Unrealized gains/ (losses)	394,000	14,524,000	-1,122,000	10,322,000
Ending balance	131,791,000	172,772,000	131,791,000	172,772,000
Financial instruments and other inventory positions owned | Convertible securities	'	'	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'	'	'
Beginning balance	'	0	'	'
Purchases	'	2,559,000	'	2,559,000
Sales	'	-2,308,000	'	-2,308,000
Transfers in	'	870,000	'	870,000
Transfers out	'	0	'	'
Realized gains/ (losses)	'	9,000	'	9,000
Unrealized gains/ (losses)	'	178,000	'	178,000
Ending balance	'	1,308,000	'	1,308,000
Financial instruments and other inventory positions owned | Fixed income securities	'	'	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'	'	'
Beginning balance	100,000	0	100,000	'
Purchases	0	100,000	0	100,000
Sales	-100,000	0	-100,000	'
Transfers in	0	0	0	'
Transfers out	0	0	0	'
Realized gains/ (losses)	0	0	0	'
Unrealized gains/ (losses)	0	0	0	'
Ending balance	0	100,000	0	100,000
Financial instruments and other inventory positions owned | Tax-exempt securities	'	'	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'	'	'
Beginning balance	1,433,000	1,431,000	1,433,000	1,429,000
Purchases	'	'	'	1,000
Sales	'	'	'	'
Transfers in	'	'	'	'
Transfers out	'	'	'	'
Realized gains/ (losses)	'	'	'	'
Unrealized gains/ (losses)	-127,000	2,000	-127,000	3,000
Ending balance	1,306,000	1,433,000	1,306,000	1,433,000
Financial instruments and other inventory positions owned | Short-term securities	'	'	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'	'	'
Beginning balance	656,000	656,000	656,000	656,000
Purchases	'	'	'	'
Sales	-25,000	'	-25,000	'
Transfers in	'	'	'	'
Transfers out	'	'	'	'
Realized gains/ (losses)	6,000	'	6,000	'
Unrealized gains/ (losses)	95,000	'	95,000	'
Ending balance	732,000	656,000	732,000	656,000
Financial instruments and other inventory positions owned | Asset-backed securities	'	'	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'	'	'
Beginning balance	107,399,000	107,654,000	119,799,000	116,171,000
Purchases	119,064,000	162,754,000	151,790,000	196,496,000
Sales	-101,878,000	-123,422,000	-150,621,000	-170,569,000
Transfers in	'	'	'	'
Transfers out	'	'	'	'
Realized gains/ (losses)	4,678,000	5,573,000	9,184,000	16,295,000
Unrealized gains/ (losses)	-137,000	-1,163,000	-1,026,000	-6,997,000
Ending balance	129,126,000	151,396,000	129,126,000	151,396,000
Financial instruments and other inventory positions owned | Derivative contracts	'	'	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'	'	'
Beginning balance	64,000	2,372,000	691,000	827,000
Purchases	'	710,000	2,614,000	5,000
Sales	'	-896,000	'	-134,000
Transfers in	'	'	'	'
Transfers out	'	'	'	'
Realized gains/ (losses)	'	186,000	-2,614,000	43,000
Unrealized gains/ (losses)	563,000	15,507,000	-64,000	17,138,000
Ending balance	627,000	17,879,000	627,000	17,879,000
Investments [Member]	'	'	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'	'	'
Beginning balance	60,954,000	41,653,000	49,240,000	33,245,000
Purchases	'	10,000,000	10,000,000	15,362,000
Sales	-2,358,000	'	-2,358,000	'
Transfers in	'	'	'	'
Transfers out	'	'	'	'
Realized gains/ (losses)	2,358,000	'	2,358,000	4,000
Unrealized gains/ (losses)	-2,387,000	1,914,000	-673,000	4,956,000
Ending balance	$58,567,000	$53,567,000	$58,567,000	$53,567,000

Variable_Interest_Entities_Add

Variable Interest Entities - Additional Information (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
Variable Interest Entities Disclosure [Abstract]	'	'
Variable Interest Entity, Consolidated, Carrying Amount, Liabilities	$0	$0
Variable interest entity, nonconsolidated total assets	700,000,000	800,000,000
Variable interest entities, exposure to loss	$11,500,000	'

Receivables_from_and_Payables_2

Receivables from and Payables to Brokers, Dealers and Clearing Organizations - Amounts Receivable from Brokers, Dealers and Clearing Organizations (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Disclosure Amounts Receivable From Brokers Dealers And Clearing Organizations [Abstract]	'	'
Receivable arising from unsettled securities transactions	$34,030	$59,657
Deposits paid for securities borrowed	21,646	36,278
Receivable from clearing organizations	14,864	966
Deposits with clearing organizations	51,918	20,995
Securities failed to deliver	14,504	593
Other	21,528	8,624
Brokers, dealers and clearing organizations	$158,490	$127,113

Receivables_from_and_Payables_3

Receivables from and Payables to Brokers, Dealers and Clearing Organizations - Amounts Payable to Brokers, Dealers and Clearing Organizations (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Disclosure Amounts Payable To Brokers Dealers And Clearing Organizations [Abstract]	'	'
Payable arising from unsettled securities transactions	$206,464	$5,643
Payable to clearing organizations	13,088	9,462
Securities failed to receive	5,491	744
Other	15,495	11,873
Brokers, dealers and clearing organizations	$240,538	$27,722

Collateralized_Securities_Tran2

Collateralized Securities Transactions - Summary of Repurchase Liabilities, Fair Market Value of Related Collateral Pledged and Interest Rate Charged (Details) (USD $)	Jun. 30, 2014
In Thousands, unless otherwise specified
Maturity up to 30 days [Member] | Asset-backed securities	'
Assets Sold under Agreements to Repurchase [Line Items]	'
Repurchase Liabilities	$11,815
Fair Market Value	$15,686
Maturity up to 30 days [Member] | Asset-backed securities | Minimum	'
Assets Sold under Agreements to Repurchase [Line Items]	'
Interest Rate	1.66%
Maturity up to 30 days [Member] | Asset-backed securities | Maximum	'
Assets Sold under Agreements to Repurchase [Line Items]	'
Interest Rate	1.75%
On demand maturities | US Treasury and Government [Member] | Minimum	'
Assets Sold under Agreements to Repurchase [Line Items]	'
Interest Rate	0.00%
On demand maturities | US Treasury and Government [Member] | Maximum	'
Assets Sold under Agreements to Repurchase [Line Items]	'
Interest Rate	0.00%

Collateralized_Securities_Tran3

Collateralized Securities Transactions - Additional Information (Detail) (USD $)	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Collateralized Securities Transactions Disclosure [Abstract]	'	'	'
Other Comprehensive (Income) Loss, Net of Tax, Portion Attributable to Noncontrolling Interest	$0	$0	'
Reverse Repurchase, Offset Value	0	'	0
Securities purchased under agreements to resell, securities borrowed and margin agreements on terms that permit to repledge or resell the securities to others	183,600,000	'	212,400,000
Securities either pledged or otherwise transferred to others in connection with financing activities or to satisfy commitments under financial instruments and other inventory positions sold, but not yet purchased	174,000,000	'	194,900,000
Securities loaned	$0	'	$0

Investments_Details

Investments (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Investments [Abstract]	'	'
Investments at fair value	$88,486	$69,930
Investments at cost	8,271	20,709
Investments accounted for under the equity method	19,632	21,404
Total investments	116,389	112,043
Less investments attributable to noncontrolling interests	-26,263	-21,137
Investments less portion attributable to noncontolling interest	$90,126	$90,906

Investments_Additional_Informa

Investments - Additional Information (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
Investment [Line Items]	'	'
Investments	$116,389,000	$112,043,000
Estimated fair market value of investments carried at cost	13,000,000	'
Debt investment in private company	'	'
Investment [Line Items]	'	'
Investments	$0	'

Other_Assets_Details

Other Assets (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]	'	'
Net deferred income tax assets	$31,310	$36,252
Fee receivables	33,306	34,415
Accrued interest receivables	9,250	9,793
Forgivable loans, net	9,164	7,879
Prepaid expenses	5,294	5,237
Other	10,028	8,516
Total other assets	$98,352	$102,092

Goodwill_and_Intangible_Assets2

Goodwill and Intangible Assets - Changes in Carrying Value of Goodwill and Intangible Assets (Details) (USD $)

3 Months Ended

6 Months Ended

3 Months Ended

6 Months Ended

3 Months Ended

6 Months Ended

0 Months Ended

3 Months Ended

In Thousands, unless otherwise specified

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2013

Jul. 16, 2013

Jun. 30, 2014

Capital Markets

Capital Markets

Capital Markets

Capital Markets

Asset Mgmt [Member]

Asset Mgmt [Member]

Asset Mgmt [Member]

Asset Mgmt [Member]

Seattle-Northwest Securities Corporation and Edgeview Partners, L.P.

Seattle-Northwest Securities Corporation and Edgeview Partners, L.P.

Capital Markets

Goodwill

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Goodwill beginning balance

'

'

$210,634

'

'

'

$13,790

'

'

'

$196,844

'

'

'

Goodwill acquired

'

'

'

'

'

'

0

'

'

'

'

'

-15,000

'

Impairment charge

'

'

'

'

'

'

0

'

'

'

'

'

'

'

Goodwill ending balance

211,878

'

211,878

'

15,034

'

15,034

'

196,844

'

196,844

'

15,034

'

Intangible assets

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Intangible assets beginning balance

'

'

39,930

'

'

'

5,316

'

'

'

34,614

'

'

'

Amortization of intangible assets

-2,318

-1,661

-4,636

-3,322

-743

0

-1,486

0

-1,575

-1,661

-3,150

-3,322

'

'

Intangible assets ending balance

35,294

'

35,294

'

3,830

'

3,830

'

31,464

'

31,464

'

'

'

Goodwill measurement period adjustment

'

'

$1,244

'

'

'

'

'

'

'

$0

'

'

$1,244

ShortTerm_Financing_Summary_of

Short-Term Financing - Summary of Short Term Financing and Weighted Average Interest Rate on Borrowings (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
Short-term Debt [Line Items]	'	'
Oustanding Balance	$362,401,000	$514,711,000
Commercial paper (secured)	'	'
Short-term Debt [Line Items]	'	'
Oustanding Balance	271,471,000	280,294,000
Weighted Average Interest Rate	1.58%	1.59%
Prime broker arrangement	'	'
Short-term Debt [Line Items]	'	'
Oustanding Balance	$90,930,000	$234,417,000
Weighted Average Interest Rate	0.91%	0.90%

ShortTerm_Financing_Additional

Short-Term Financing - Additional Information (Detail) (USD $)

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Dec. 31, 2013

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Commercial paper (secured)

Commercial paper (secured)

Commercial paper (secured)

Commercial paper (secured)

Commercial paper (secured)

Commercial paper (secured)

Commercial paper (secured)

Commercial paper (secured)

Line of Credit [Member]

Line of Credit [Member]

Committed Credit Facility [Member]

program

Minimum

Maximum

CP Series A

CP Series II A

CP Series III A

Covenant Requirement

Committed Credit Facility [Member]

Uncommitted Credit Facility [Member]

Covenant Requirement

banks

Short-term Debt [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

Senior secured commercial paper notes, maturity period

'

'

'

'

'27 days

'270 days

'

'

'

'

'

'

'

Number of commercial paper programs

'

'

3

'

'

'

'

'

'

'

'

'

'

Weighted average maturity period

'

'

'

'

'

'

'162 days

'99 days

'33 days

'

'

'

'

Net Capital

$159,100,000

'

'

'

'

'

'

'

'

$120,000,000

'

'

'

Debt term

'

'

'

'

'

'

'

'

'

'

'1 year

'

'

Line of credity, maximum borrowing capacity

'

'

'

'

'

'

'

'

'

'

250,000,000

185,000,000

'

Minimum net capital required

'

'

'

'

'

'

'

'

'

'

'

'

120,000,000

Short-term financing

$362,401,000

$514,711,000

$271,471,000

$280,294,000

'

'

'

'

'

'

$0

$0

'

Number of banks

'

'

'

'

'

'

'

'

'

'

'

2

'

Variable_Rate_Senior_Notes_Add

Variable Rate Senior Notes - Additional Information (Details) (USD $)	6 Months Ended				6 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2014	Nov. 30, 2012	Nov. 30, 2012	Jun. 02, 2014	Jun. 30, 2014	Nov. 30, 2012	Jun. 30, 2014	Jun. 30, 2014
		Senior Notes	Senior Notes	Senior Notes	Senior Notes	Senior Notes	Senior Notes	Senior Notes
		class	Class A Variable Rate Senior Notes Due May 2014 [Member]	Class A Variable Rate Senior Notes Due May 2017 [Member]	Class A Variable Rate Senior Notes Due May 2017 [Member]	Class B Variable Rate Senior Notes Due November 2015	Class B Variable Rate Senior Notes Due November 2015	Covenant Requirement
					Three-Month LIBOR		Three-Month LIBOR
Debt Instrument [Line Items]	'	'	'	'	'	'	'	'
Face amount	'	$125	$50	$50	'	$75	'	'
Number of classes of notes	'	2	'	'	'	'	'	'
Basis spread on variable rate	'	'	'	'	3.00%	'	4.50%	'
Note purchase agreement, days to pay interest	'5 days	'	'	'	'	'	'	'
Note purchase agreement, event of default, maximum indebtedness	10	'	'	'	'	'	'	'
Minimum net capital required	'	'	'	'	'	'	'	$120

Contingencies_and_Commitments_1

Contingencies and Commitments - Aggregate Minimum Lease Commitments under Operating Leases (Details) (USD $)	Jun. 30, 2014
In Thousands, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]	'
Remainder of 2014	$5,242
2015	11,957
2016	11,871
2017	9,877
2018	9,563
Thereafter	35,441
Total	$83,951

Shareholders_Equity_Additional

Shareholders' Equity - Additional Information (Detail) (USD $)	3 Months Ended	6 Months Ended
	Sep. 30, 2012	Jun. 30, 2014	Jun. 30, 2013
Stockholders Equity Note [Line Items]	'	'	'
Repurchase of common stock, authorized amount	$100,000,000	'	'
Common stock repurchase authorized, remaining amount	'	39,500,000	'
Shares of common stock purchased from restricted stock award related to recipients' employment tax obligations	'	217,655	'
Repurchase of common stock for employee tax withholding	'	8,806,000	'
Number of common stock issued for retirement plan obligations	'	103,598	96,049
Stock Issued During Period, Value, Treasury Stock Reissued	'	4,156,000	3,939,000
Reissuance of treasury shares as a result of employee vesting	'	521,504	741,972
Retirement Plan	'	'	'
Stockholders Equity Note [Line Items]	'	'	'
Stock Issued During Period, Value, Treasury Stock Reissued	'	$4,200,000	$3,900,000

Noncontrolling_Interests_Addit

Noncontrolling Interests - Additional Information (Detail) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Noncontrolling Interest Note [Line Items]	'	'
Noncontrolling interests	$141,909	$147,396
Municipal bond fund	'	'
Noncontrolling Interest Note [Line Items]	'	'
Noncontrolling interests	115,600	126,300
Merchant banking fund	'	'
Noncontrolling Interest Note [Line Items]	'	'
Noncontrolling interests	18,500	14,100
Other private equity investments	'	'
Noncontrolling Interest Note [Line Items]	'	'
Noncontrolling interests	$7,800	$7,000

Noncontrolling_Interest_Rollfo

Noncontrolling Interest - Rollforward (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]	'	'	'	'
Stockholders' Equity Attributable to Parent	'	'	$734,676	'
Noncontrolling interest, beginning balance	'	'	147,396	'
Beginning Balance	'	'	882,072	'
Net income/(loss) applicable to Piper Jaffray Companies	18,213	2,488	35,961	12,634
Net income/(loss)	20,368	-182	43,254	11,865
Amortization/issuance of restricted stock	'	'	20,163	'
Stock Issued During Period, Value, Stock Options Exercised	'	'	1,322	'
Repurchase of common stock for employee tax withholding	'	'	-8,806	'
Issuance of treasury shares for 401k match	'	'	4,156	3,939
Shares reserved to meet deferred compensation obligations	'	'	120	'
Other comprehensive income	'	'	256	'
Fund Capital Contributions	'	'	-12,780	'
Stockholders' Equity Attributable to Parent	787,848	'	787,848	'
Noncontrolling interest, ending balance	141,909	'	141,909	'
Ending Balance	929,757	'	929,757	'
Parent	'	'	'	'
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]	'	'	'	'
Amortization/issuance of restricted stock	'	'	20,163	'
Stock Issued During Period, Value, Stock Options Exercised	'	'	1,322	'
Repurchase of common stock for employee tax withholding	'	'	-8,806	'
Issuance of treasury shares for 401k match	'	'	4,156	'
Shares reserved to meet deferred compensation obligations	'	'	120	'
Other comprehensive income	'	'	256	'
Fund Capital Contributions	'	'	0	'
Noncontrolling Interests	'	'	'	'
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]	'	'	'	'
Amortization/issuance of restricted stock	'	'	0	'
Stock Issued During Period, Value, Stock Options Exercised	'	'	0	'
Repurchase of common stock for employee tax withholding	'	'	0	'
Issuance of treasury shares for 401k match	'	'	0	'
Shares reserved to meet deferred compensation obligations	'	'	0	'
Other comprehensive income	'	'	0	'
Fund Capital Contributions	'	'	($12,780)	'

Compensation_Plans_Additional_

Compensation Plans - Additional Information (Detail) (USD $)

3 Months Ended

6 Months Ended

0 Months Ended

6 Months Ended

12 Months Ended

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

15-May-12

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Jun. 30, 2014

Dec. 31, 2010

Jun. 30, 2014

plan

plan

Minimum

Maximum

Maximum

Annual grants

Sign-on grants

Sign-on grants

Restricted Stock Units

Restricted Stock Units

Restricted Stock Units

Restricted Stock Units

Restricted Stock

Stock Options

Amended And Restated 2003 Annual And Long -Term Incentive Plan

Amended And Restated 2003 Annual And Long -Term Incentive Plan

2010 Employment Inducement Award Plan

Deferred Compensation Plans [Member]

New Employees [Member]

New Employees [Member]

Minimum

Maximum

Maximum

Maximum

Maximum

Award Earned Based on Shareholder Return Relative to Predetermined Peer Group

Award Earned Based on Total Shareholder Return

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of stock-based compensation plans

2

'

2

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Equity award grants authorized

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

7,000,000

'

'

Shares available for future issuance

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

900,000

'

'

'

Award vesting period in years

'

'

'

'

'

'

'

'3 years

'

'

'

'

'

'

'

'

'

'

'5 years

'

Annual grant expense period

'

'

'

'

'

'

'

'1 year

'

'

'

'

'

'

'

'

'

'

'

'

sign on grant expense period

'

'

'

'

'

'

'

'

'2 years

'5 years

'

'

'

'

'

'

'

'

'

'

Forfeitures recorded as a result of violating the post-termination restrictions

'

$400,000

'

$700,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Restricted stock units, performance period

'

'

'

'

'

'

'

'

'

'

'36 months

'

'

'

'

'

'

'

'

'

Weighted average period over which restricted stock expense expected to be recognized

'

'

'2 years 8 months 1 day

'

'

'

'

'

'

'

'3 years

'

'

'

'

'

'

'

'

'

Award earning percentage

'

'

'

'

'

'

'

'

'

'

'

'

50.00%

50.00%

'

'

'

'

'

'

Number of years risk free interest rate

'

'

'

'

'

'

'

'

'

'

'

'3 years

'

'

'

'

'

'

'

'

Term of stock options

'

'

'

'

'

'10 years

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Restricted shares granted to ARI employees, value

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

7,000,000

'

Restricted shares granted, share

'

'

'

'

'

'

'

'

'

'

'

115,290

'

'

404,474

'

'

'

158,801

'

Compensation expense related to employee restricted stock awards

8,100,000

3,800,000

13,300,000

4,400,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Tax benefit related to compensation costs for stock-based compensation arrangements

3,100,000

1,500,000

5,200,000

1,700,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Unrecognized compensation cost related to restricted stock

12,700,000

'

12,700,000

'

'

'

'

'

'

'

'

'

'

'

'

0

'

'

'

'

Mutual funds

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

6,100,000

Deferred liabilities

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$6,100,000

Acquisition related compensation awards vesting period

'

'

'3 years

'

'2 years

'

'5 years

'

'

'

'

'

'

'

'

'

'

'

'

'

Compensation_Plans_Summary_of_

Compensation Plans - Summary of Outstanding Equity Awards (Details)	Jun. 30, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Restricted stock outstanding	1,200,557	'
Total restricted stock outstanding	1,305,053	'
Stock options outstanding	321,490	469,289
ARI [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Total restricted stock outstanding	104,496	'
Restricted Stock Units	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Leadership grants	405,826	'
Amended And Restated 2003 Annual And Long -Term Incentive Plan	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Restricted stock outstanding	1,171,398	'
Amended And Restated 2003 Annual And Long -Term Incentive Plan | Annual grants	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Restricted stock outstanding	825,343	'
Amended And Restated 2003 Annual And Long -Term Incentive Plan | Sign-on grants	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Restricted stock outstanding	346,055	'
2010 Employment Inducement Award Plan	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Restricted stock outstanding	29,159	'

Compensation_Plans_RSU_Valuati

Compensation Plans - RSU Valuation Assumptions (Details) (Restricted Stock Units)	6 Months Ended
	Jun. 30, 2014
Grant Year 2014 [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Risk-free Interest Rate	0.82%
Expected Stock Price Volatility	41.30%
Grant Year 2013	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Risk-free Interest Rate	0.40%
Expected Stock Price Volatility	44.00%
Grant Year 2012	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Risk-free Interest Rate	0.38%
Expected Stock Price Volatility	47.60%

Compensation_Plans_Unvested_Re

Compensation Plans - Unvested Restricted Stock (Details) (USD $)	3 Months Ended		6 Months Ended
In Millions, except Share data, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	'	'	'2 years 8 months 1 day	'
Allocated Share-based Compensation Expense	$8.10	$3.80	$13.30	$4.40
Weighted Average Grant Date Fair Value (in dollars per share)	'	'	'	'
Restricted Stock Award, Forfeitures	'	0.4	'	0.7
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	$3.10	$1.50	$5.20	$1.70
Restricted Stock	'	'	'	'
Unvested Restricted Stock or Stock Units	'	'	'	'
Beginning Balance	'	'	1,582,062	'
Granted	'	'	404,474	'
Vested	'	'	-675,940	'
Cancelled	'	'	-5,543	'
Ending Balance	1,305,053	'	1,305,053	'
Weighted Average Grant Date Fair Value (in dollars per share)	'	'	'	'
Beginning Balance	'	'	$35.25	'
Granted	'	'	$40.13	'
Vested	'	'	$35.99	'
Cancelled	'	'	$33.72	'
Ending Balance	$36.39	'	$36.39	'

Compensation_Plans_Unvested_Re1

Compensation Plans - Unvested Restricted Stock Units (Details) (Restricted Stock Units, USD $)	6 Months Ended
	Jun. 30, 2014
Restricted Stock Units	'
Unvested Restricted Stock or Stock Units	'
Beginning Balance	290,536
Granted	115,290
Vested	0
Cancelled	0
Ending Balance	405,826
Weighted Average Grant Date Fair Value (in dollars per share)	'
Beginning Balance	$15.83
Granted	$23.42
Vested	$0
Cancelled	$0
Ending Balance	$17.99

Compensation_Plans_Stock_Optio

Compensation Plans - Stock Options (Details) (USD $)	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Options Outstanding	'	'	'
Beginning Balance	469,289	'	'
Granted	0	'	'
Exercised	-34,247	'	'
Cancelled	-55	'	'
Expired	-113,497	'	'
Ending Balance	321,490	'	'
Options exercisable at period end	321,490	'	'
Weighted Average Exercise Price (in dollars per share)	'	'	'
Beginning Balance	$44.83	'	'
Granted	$0	'	'
Exercised	$35.75	'	'
Cancelled	$39.62	'	'
Expired	$47.72	'	'
Ending Balance	$44.78	'	'
Options exercisable at period end	$44.78	'	'
Weighted Average Remaining Contractual Term (in Years)	'	'	'
Weighted Average Remaining Contractual Term (in Years)	'2 years 2 months	'2 years	'
Options exercisable at period end	'2 years 2 months	'	'
Aggregate Intrinsic Value	'	'	'
Aggregate Intrinsic Value of Stock Options	$3,125,267	'	$288,318
Options exercisable at end of period	$3,125,267	'	'

Earnings_Per_Share_Details

Earnings Per Share (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, except Share data, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Earnings Per Share [Abstract]	'	'	'	'
Net income/(loss) from continuing operations	$18,213	$4,359	$35,961	$15,026
Net loss from discontinued operations	0	-1,871	0	-2,392
Net income applicable to Piper Jaffray Companies	18,213	2,488	35,961	12,634
Earnings allocated to participating securities	-1,496	-222	-3,155	-1,301
Net income applicable to Piper Jaffray Companies' common shareholders	$16,717	$2,266	$32,806	$11,333
Shares for basic and diluted calculations:	'	'	'	'
Average shares used in basic computation	14,958,000	15,621,000	14,786,000	15,602,000
Incremental common share attributable to share-based payment arrangements	55,000	5,000	50,000	17,000
Average shares used in diluted computation	15,013,000	15,626,000	14,836,000	15,619,000
Earnings/(loss) per basic common share	'	'	'	'
Income from continuing operations	$1.12	$0.25	$2.22	$0.86
Loss from discontinued operations	$0	($0.11)	$0	($0.14)
Earnings per basic common share	$1.12	$0.15	$2.22	$0.73
Earnings/(loss) per diluted common share	'	'	'	'
Income from continuing operations	$1.11	$0.25	$2.21	$0.86
Loss from discontinued operations	$0	($0.11)	$0	($0.14)
Earnings per diluted common share	$1.11	$0.15	$2.21	$0.73
Weighted average participating shares outstanding	1,343,399	1,531,100	1,426,656	1,791,940

Segment_Reporting_Reportable_S

Segment Reporting - Reportable Segment Financial Results (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Segment Reporting Information [Line Items]	'	'	'	'
Investment banking	$103,813	$53,255	$192,287	$94,076
Institutional sales and trading	34,528	24,611	78,562	64,758
Asset management	22,266	18,427	43,225	36,883
Investment income	2,921	-2,059	9,689	3,006
Net revenues	170,031	99,772	338,164	209,305
Goodwill impairment	'	'	'	'
Operating expenses	139,614	96,439	275,034	187,804
Segment pre-tax operating income/(loss)	30,417	3,333	63,130	21,501
Pre-tax operating margin	17.90%	3.30%	18.70%	10.30%
Intangible asset amortization expense	2,318	1,661	4,636	3,322
Capital Markets	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Investment banking	103,927	53,297	192,495	94,188
Institutional sales and trading	39,451	29,645	88,949	74,768
Asset management	1,388	564	3,125	1,583
Investment income	4,998	184	15,376	6,321
Interest Expense, Long-term Debt	-1,705	-1,872	-3,445	-3,821
Net revenues	148,059	81,818	296,500	173,039
Goodwill impairment	'	'	0	'
Operating expenses	124,691	83,937	245,621	162,395
Segment pre-tax operating income/(loss)	23,368	-2,119	50,879	10,644
Pre-tax operating margin	15.80%	-2.60%	17.20%	6.20%
Intangible asset amortization expense	743	0	1,486	0
Asset Mgmt [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Management fees	20,600	17,558	39,736	34,644
Performance fees	278	305	364	656
Asset management	20,878	17,863	40,100	35,300
Investment income	1,094	91	1,564	966
Net revenues	21,972	17,954	41,664	36,266
Goodwill impairment	'	'	'	'
Operating expenses	14,923	12,502	29,413	25,409
Segment pre-tax operating income/(loss)	7,049	5,452	12,251	10,857
Pre-tax operating margin	32.10%	30.40%	29.40%	29.90%
Intangible asset amortization expense	1,575	1,661	3,150	3,322
Equities Financing [Member] | Capital Markets	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Investment banking	44,058	21,772	79,359	36,075
Debt Financing [Member] | Capital Markets	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Investment banking	20,174	22,131	33,713	39,163
Advisory Services | Capital Markets	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Investment banking	39,695	9,394	79,423	18,950
Equity securities | Capital Markets	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Institutional sales and trading	18,366	21,384	42,626	42,119
Debt securities | Capital Markets	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Institutional sales and trading	21,085	8,261	46,323	32,649
Operating Expense [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Operating expenses	$139,614	$96,439	$275,034	$187,804

Segment_Reporting_Net_Revenues

Segment Reporting - Net Revenues by Geographic Locations (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Segment Reporting Information [Line Items]	'	'	'	'
Net revenues	$170,031	$99,772	$338,164	$209,305
United States	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Net revenues	167,552	97,195	332,876	202,921
Europe	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Net revenues	$2,479	$2,577	$5,288	$6,384

Segment_Reporting_LongLived_As

Segment Reporting - Long-Lived Assets By Geographic Region (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Long-Lived Assets by Geographical Areas [Line Items]	'	'
Long Lived Assets	$294,133	$302,930
United States	'	'
Long-Lived Assets by Geographical Areas [Line Items]	'	'
Long Lived Assets	287,737	296,516
Europe	'	'
Long-Lived Assets by Geographical Areas [Line Items]	'	'
Long Lived Assets	$6,396	$6,414

Net_Capital_Requirements_and_O1

Net Capital Requirements and Other Regulatory Matters - Additional Information (Detail) (USD $)	Jun. 30, 2014
In Millions, unless otherwise specified
Schedule Of Compliance With Regulatory Capital Requirements For Broker Dealer [Line Items]	'
Net capital requirement	$1
Net capital requirement, percentage of aggregate debit balances arising from customer transactions	2.00%
Net capital requirement, percent of aggregate debit balances under restriction on business expansion or dividend payment	5.00%
Amount of capital that exceeds the minimum net capital required	159.1
Minimum net capital required	160.5
Committed Credit Facility [Member] | Covenant Requirement	'
Schedule Of Compliance With Regulatory Capital Requirements For Broker Dealer [Line Items]	'
Minimum Net Capital Required	120
Commercial Paper [Member] | Covenant Requirement	'
Schedule Of Compliance With Regulatory Capital Requirements For Broker Dealer [Line Items]	'
Amount of capital that exceeds the minimum net capital required	$120