Piper Sandler Companies (PIPR) 10-K 26 Feb 15 2014 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Feb. 18, 2015	Jun. 30, 2014
Document and Entity Information [Abstract]
Document Type	10-K
Amendment Flag	FALSE
Document Period End Date	31-Dec-14
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY
Trading Symbol	PJC
Entity Registrant Name	Piper Jaffray Companies
Entity Central Index Key	1230245
Current Fiscal Year End Date	-19
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		16,735,300
Entity Common Stock, Shares outstanding held by non-affiliates			15,685,715
Entity Public Float			$812

Consolidated_Statements_of_Fin

Consolidated Statements of Financial Condition (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Assets
Cash and cash equivalents	$15,867	$123,683
Cash and cash equivalents segregated for regulatory purposes	25,011	43,012
Receivables:
Customers	9,658	11,633
Brokers, dealers and clearing organizations	161,009	127,113
Securities purchased under agreements to resell	308,165	167,875
Financial instruments and other inventory positions owned	507,794	406,513
Financial instruments and other inventory positions owned and pledged as collateral	1,108,567	957,515
Total financial instruments and other inventory positions owned	1,616,361	1,364,028
Fixed assets (net of accumulated depreciation and amortization of $47,327 and $62,311, respectively)	18,171	16,114
Goodwill	211,878	210,634
Intangible assets (net of accumulated amortization of $41,141 and $31,869, respectively)	30,658	39,930
Investments	126,840	112,043
Other assets	100,299	102,092
Total assets	2,623,917	2,318,157
Liabilities and Shareholders’ Equity
Short-term financing	377,767	514,711
Variable rate senior notes	125,000	125,000
Payables:
Customers	13,328	33,109
Brokers, dealers and clearing organizations	25,564	27,722
Securities sold under agreements to repurchase	102,646	4,397
Financial instruments and other inventory positions sold, but not yet purchased	738,124	512,833
Accrued compensation	228,877	159,928
Other liabilities and accrued expenses	43,151	58,385
Total liabilities	1,654,457	1,436,085
Shareholders’ equity:
Common stock, $0.01 par value: Shares authorized: 100,000,000 at December 31, 2014 and December 31, 2013; Shares issued: 19,523,371 at December 31, 2014 and 19,537,127 at December 31, 2013; Shares outstanding: 15,265,420 at December 31, 2014 and 14,383,418 at December 31, 2013	195	195
Additional paid-in capital	735,415	740,321
Retained earnings	227,065	163,893
Less common stock held in treasury, at cost: 4,257,951 shares at December 31, 2014 and 5,153,709 shares at December 31, 2013	-143,140	-170,629
Accumulated other comprehensive income	377	896
Total common shareholders’ equity	819,912	734,676
Noncontrolling interests	149,548	147,396
Total shareholders’ equity	969,460	882,072
Total liabilities and shareholders’ equity	$2,623,917	$2,318,157

Consolidated_Statements_of_Fin1

Consolidated Statements of Financial Condition (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, except Share data, unless otherwise specified
Statement of Financial Position [Abstract]
Accumulated depreciation and amortization on fixed assets	$47,327	$62,311
Accumulated amortization on intangible assets	$41,141	$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	15,265,420	14,383,418
Common stock held in treasury, shares	4,257,951	5,153,709

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues:
Investment banking	$369,811	$248,563	$232,958
Institutional brokerage	156,809	146,648	166,642
Asset management	85,062	83,045	65,699
Interest	48,716	50,409	37,845
Investment income	12,813	21,566	4,903
Total revenues	673,211	550,231	508,047
Interest expense	25,073	25,036	19,095
Net revenues	648,138	525,195	488,952
Non-interest expenses:
Compensation and benefits	394,510	322,464	296,882
Occupancy and equipment	28,231	25,493	26,454
Communications	22,732	21,431	20,543
Floor brokerage and clearance	7,621	8,270	8,054
Marketing and business development	27,260	21,603	19,908
Outside services	37,055	32,982	27,998
Restructuring and integration costs	0	4,689	3,642
Intangible asset amortization expense	9,272	7,993	6,944
Other operating expenses	11,146	4,657	9,516
Total non-interest expenses	537,827	449,582	419,941
Income from continuing operations before income tax expense	110,311	75,613	69,011
Income tax expense	35,986	20,390	19,470
Income from continuing operations	74,325	55,223	49,541
Discontinued operations:
Loss from discontinued operations, net of tax	0	-4,739	-5,807
Net income	74,325	50,484	43,734
Net income applicable to noncontrolling interests	11,153	5,394	2,466
Net income applicable to Piper Jaffray Companies	63,172	45,090	41,268
Net income applicable to Piper Jaffray Companies’ common shareholders	58,141	40,596	35,335
Amounts applicable to Piper Jaffray Companies
Net income from continuing operations	63,172	49,829	47,075
Net loss from discontinued operations	$0	($4,739)	($5,807)
Earnings/(loss) per basic common share
Income from continuing operations	$3.88	$2.98	$2.58
Loss from discontinued operations	$0	($0.28)	($0.32)
Earnings per basic common share	$3.88	$2.70	$2.26
Earnings/(loss) per diluted common share
Income from continuing operations	$3.87	$2.98	$2.58
Loss from discontinued operations	$0	($0.28)	($0.32)
Earnings per diluted common share	$3.87	$2.70	$2.26
Weighted average number of common shares outstanding
Basic	14,971	15,046	15,615
Diluted	15,025	15,061	15,616

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net income	$74,325	$50,484	$43,734
Other comprehensive income/(loss), net of tax:
Adjustment to unrecognized pension cost	0	-38	0
Foreign currency translation adjustment	-519	267	62
Total other comprehensive income, net of tax	-519	229	62
Comprehensive income	73,806	50,713	43,796
Comprehensive income applicable to noncontrolling interests	11,153	5,394	2,466
Comprehensive income applicable to Piper Jaffray Companies	$62,653	$45,319	$41,330

Consolidated_Statements_of_Cha

Consolidated Statements of Changes in Shareholders' Equity (USD $)	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Parent	Noncontrolling Interests
In Thousands, except Share data
Beginning Balance at Dec. 31, 2011	$750,600	$195	$791,166	$77,535	($151,110)	$605	$718,391	$32,209
Beginning Balance (in shares) at Dec. 31, 2011		15,750,188
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	43,734	0	0	41,268	0	0	41,268	2,466
Amortization/issuance of restricted stock	16,681	0	16,681	0	0	0	16,681	0
Repurchase of common stock through share repurchase program, shares		-1,645,458
Repurchase of common stock through share repurchase program	-38,068	0	0	0	38,068	0	-38,068	0
Issuance of treasury shares for restricted stock vestings (in shares)		1,323,427
Issuance of treasury shares for restricted stock vestings	0	0	-50,776	0	50,776	0	0	0
Repurchase of common stock for employee tax withholding (in shares)	385,449	-385,449
Repurchase of common stock for employee tax withholding	9,096	0	0	0	-9,096	0	9,096	0
Issuance of treasury shares for 401k match (in shares)	165,241	165,241
Issuance of treasury shares for 401k match	3,814	0	-2,745	0	6,559	0	3,814	0
Shares reserved to meet deferred compensation obligations (in shares)		5,847
Shares reserved to meet deferred compensation obligations	240	0	240	0	0	0	240	0
Other comprehensive loss	62	0	0	0	0	62	62	0
Fund capital contributions, net	22,208	0	0	0	0	0	0	22,208
Ending Balance at Dec. 31, 2012	790,175	195	754,566	118,803	-140,939	667	733,292	56,883
Ending Balance (in shares) at Dec. 31, 2012		15,213,796
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	50,484	0	0	45,090	0	0	45,090	5,394
Amortization/issuance of restricted stock	23,528	0	23,528	0	0	0	23,528	0
Repurchase of common stock through share repurchase program, shares		-1,719,662
Repurchase of common stock through share repurchase program	-55,929	0	0	0	55,929	0	-55,929	0
Issuance of treasury shares for restricted stock vestings (in shares)		1,173,180
Issuance of treasury shares for restricted stock vestings	0	0	-38,636	0	38,636	0	0	0
Repurchase of common stock for employee tax withholding (in shares)	386,713	-386,713
Repurchase of common stock for employee tax withholding	15,533	0	0	0	-15,533	0	15,533	0
Issuance of treasury shares for 401k match (in shares)	96,049	96,049
Issuance of treasury shares for 401k match	3,939	0	803	0	3,136	0	3,939	0
Shares reserved to meet deferred compensation obligations (in shares)		6,768
Shares reserved to meet deferred compensation obligations	60	0	60	0	0	0	60	0
Other comprehensive loss	229	0	0	0	0	229	229	0
Fund capital contributions, net	85,119	0	0	0	0	0	0	85,119
Ending Balance at Dec. 31, 2013	882,072	195	740,321	163,893	-170,629	896	734,676	147,396
Ending Balance (in shares) at Dec. 31, 2013		14,383,418
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	74,325	0	0	63,172	0	0	63,172	11,153
Amortization/issuance of restricted stock	23,649	0	23,649	0	0	0	23,649	0
Issuance of treasury shares for options exercised (in shares)		137,864
Issuance of treasury shares for options exercised	5,452	0	834	0	4,618	0	5,452	0
Issuance of treasury shares for restricted stock vestings (in shares)		892,385
Issuance of treasury shares for restricted stock vestings	0	0	-30,295	0	30,295	0	0	0
Repurchase of common stock for employee tax withholding (in shares)	256,055	256,055
Repurchase of common stock for employee tax withholding	10,854	0	0	0	10,854	0	10,854	0
Issuance of treasury shares for 401k match (in shares)	103,598	103,598
Issuance of treasury shares for 401k match	4,156	0	726	0	3,430	0	4,156	0
Shares reserved to meet deferred compensation obligations (in shares)		4,210
Shares reserved to meet deferred compensation obligations	180	0	180	0	0	0	180	0
Other comprehensive loss	-519	0	0	0	0	-519	-519	0
Fund capital contributions, net	-9,001	0	0	0	0	0	0	-9,001
Ending Balance at Dec. 31, 2014	$969,460	$195	$735,415	$227,065	($143,140)	$377	$819,912	$149,548
Ending Balance (in shares) at Dec. 31, 2014		15,265,420

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating Activities:
Net income	$74,325	$50,484	$43,734
Adjustments to reconcile net income to net cash provided by/(used in) operating activities:
Depreciation and amortization of fixed assets	5,269	5,714	7,005
Deferred income taxes	-10,843	-2,630	11,458
Loss on sale of FAMCO	0	1,876	0
Loss on disposal of fixed assets	0	0	1,624
Share-based and deferred compensation	28,764	21,598	20,641
Goodwill impairment	0	0	5,508
Amortization of intangible assets	9,272	7,993	7,669
Amortization of forgivable loans	5,316	6,300	8,057
Decrease/(increase) in operating assets:
Cash and cash equivalents segregated for regulatory purposes	18,001	-12,005	-5,999
Receivables:
Customers	1,975	2,162	10,395
Brokers, dealers and clearing organizations	-33,896	21,004	-23,452
Securities purchased under agreements to resell	-140,290	-22,442	14,713
Net financial instruments and other inventory positions owned	-27,042	4,685	-360,317
Investments	-14,797	-26,271	-17,444
Other assets	3,785	-3,867	-15,362
Payables:
Customers	-19,781	-8,898	12,592
Brokers, dealers and clearing organizations	-2,158	-33,559	24,720
Accrued compensation	67,247	32,233	23,424
Other liabilities and accrued expenses	-15,216	-2,354	18,945
Decrease in assets held for sale	0	605	435
Decrease in liabilities held for sale	0	-465	-128
Net cash provided by/(used in) operating activities	-50,069	42,163	-211,782
Investing Activities:
Business acquisitions, net of cash acquired	0	-24,726	0
Repayment of FAMCO note	2,000	250	0
Purchases of fixed assets, net	-7,387	-5,476	-2,131
Net cash provided by/(used in) investing activities	-5,387	-29,952	-2,131
Financing Activities:
Increase/(decrease) in short-term financing	-136,944	37,697	308,313
Issuance of variable rate senior notes	50,000	0	125,000
Repayment of variable rate senior notes	-50,000	0	0
Decrease in bank syndicated financing	0	0	-115,000
Increase/(decrease) in securities sold under agreements to repurchase	98,249	-45,603	-59,080
Increase/(decrease) in noncontrolling interests	-9,001	85,119	22,208
Repurchase of common stock	-10,854	-71,462	-47,164
Excess tax benefit from share-based compensation	1,081	47	0
Proceeds from stock option exercises	5,452	0	0
Net cash provided by/(used in) financing activities	-52,017	5,798	234,277
Currency adjustment:
Effect of exchange rate changes on cash	-343	303	-17
Net increase/(decrease) in cash and cash equivalents	-107,816	18,312	20,347
Cash and cash equivalents at beginning of year	123,683	105,371	85,024
Cash and cash equivalents at end of year	15,867	123,683	105,371
Supplemental disclosure of cash flow information –
Interest	25,345	23,487	19,357
Income taxes	58,599	745	-4,961
Non-cash financing activities –
Issuance of common stock for retirement plan obligations: 103,598 shares, 96,049 shares and 165,241 shares for the years ended December 31, 2014, 2013 and 2012, respectively	4,156	3,939	3,814
Issuance of restricted common stock for annual equity award: 402,074 shares, 431,582 shares and 487,181 shares for the years ended December 31, 2014, 2013 and 2012, respectively	$16,131	$17,699	$11,244

Consolidated_Statements_of_Cas1

Consolidated Statements of Cash Flows (Parenthetical)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Cash Flows [Abstract]
Number of common stock issued for retirement plan obligations	103,598	96,049	165,241
Number of restricted common stock issued for annual equity award	402,074	431,582	487,181

Organization_and_Basis_of_Pres

Organization and Basis of Presentation	12 Months Ended
	Dec. 31, 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 a variety of securities, including municipal bonds, mortgage-backed securities, and 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 $11.0 million of interest revenue and $10.2 million of interest expense for the year ended December 31, 2012. This change had no effect on net revenues, net income, shareholders’ equity or cash flows for any of the periods presented.

Summary_of_Significant_Account

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies
	Principles of Consolidation
	The Company determines whether it has a controlling financial interest in an entity by first evaluating whether the entity is a voting interest entity or a variable interest entity (“VIE”).
	Voting interest entities are entities in which (i) the total equity investment at risk is sufficient to enable each entity to finance itself independently and (ii) the equity holders have the obligation to absorb losses, the right to receive residual returns and the right or power to make decisions about or direct the entity’s activities that most significantly impact the entity’s economic performance. Financial Accounting Standards Board (“FASB”) Accounting Standards Codification Topic 810, “Consolidations,” (“ASC 810”) states that the usual condition for a controlling financial interest in a voting interest entity is ownership of a majority voting interest. Accordingly, the Company consolidates voting interest entities in which it has all, or a majority of, the voting interests.
	VIEs are entities that lack one or more of the characteristics of a voting interest entity. With the exception of entities eligible for the deferral codified in FASB Accounting Standards Update (“ASU”) No. 2010-10, “Consolidation: Amendments for Certain Investment Funds,” (“ASU 2010-10”) (generally asset managers and investment companies), ASC 810 states that a controlling financial interest in a VIE is present when an enterprise has one or more variable interests that have both (i) the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance and (ii) the obligation to absorb losses of the entity or the rights to receive benefits from the VIE that could potentially be significant to the VIE. Accordingly, the Company consolidates VIEs in which the Company has a controlling financial interest.
	Entities meeting the deferral provision defined by ASU 2010-10 are evaluated under the historical VIE guidance. Under the historical guidance, a controlling financial interest in an entity is present when an enterprise has one or more variable interests that will absorb a majority of the entity’s expected losses, receive a majority of the entity’s expected residual returns, or both. The enterprise with a controlling financial interest is the primary beneficiary and consolidates the VIE. Accordingly, the Company consolidates VIEs subject to the deferral provisions defined by ASU 2010-10 in which the Company is deemed to be the primary beneficiary.
	When the Company does not have a controlling financial interest in an entity but exerts significant influence over the entity’s operating and financial policies (generally defined as owning a voting or economic interest of between 20 percent to 50 percent), the Company's investment is accounted for under the equity method of accounting. The Company accounts for its investments in partnerships under the equity method of accounting. If the Company does not have a controlling financial interest in, or exert significant influence over, an entity, the Company accounts for its investment at fair value, if the fair value option was elected, or at cost.
	Cash and Cash Equivalents
	Cash and cash equivalents consist of cash and highly liquid investments with maturities of 90 days or less at the date of origination.
	In accordance with Rule 15c3-3 of the Securities Exchange Act of 1934, Piper Jaffray, as a registered broker dealer carrying customer accounts, is subject to requirements related to maintaining cash or qualified securities in a segregated reserve account for the exclusive benefit of its customers.
	Customer Transactions
	Customer securities transactions are recorded on a settlement date basis, while the related revenues and expenses are recorded on a trade-date basis. Customer receivables and payables include amounts related to both cash and margin transactions. Securities owned by customers, including those that collateralize margin or other similar transactions, are not reflected on the consolidated statements of financial condition.
	Receivables from and Payables to Brokers, Dealers and Clearing Organizations
	Receivables from brokers, dealers and clearing organizations include receivables arising from unsettled securities transactions, deposits paid for securities borrowed, receivables from clearing organizations, deposits with clearing organizations and amounts receivable for securities not delivered to the purchaser by the settlement date (“securities failed to deliver”). Payables to brokers, dealers and clearing organizations include payables arising from unsettled securities transactions, payables to clearing organizations and amounts payable for securities not received from a seller by the settlement date (“securities failed to receive”). Unsettled securities transactions related to the Company's broker dealer operations are recorded at contract value on a net basis. Unsettled securities transactions related to the Company's consolidated investment company operations are recorded on a gross basis.
	Collateralized Securities Transactions
	Securities purchased under agreements to resell and securities sold under agreements to repurchase are carried at the contractual amounts at which the securities will be subsequently resold or repurchased, including accrued interest. It is the Company’s policy to take possession or control of securities purchased under agreements to resell at the time these agreements are entered into. The counterparties to these agreements typically are primary dealers of U.S. government securities and major financial institutions. Collateral is valued daily, and additional collateral is obtained from or refunded to counterparties when appropriate.
	Securities borrowed and loaned result from transactions with other broker dealers or financial institutions and are recorded at the amount of cash collateral advanced or received. These amounts are included in receivables from and payables to brokers, dealers and clearing organizations on the consolidated statements of financial condition. Securities borrowed transactions require the Company to deposit cash or other collateral with the lender. Securities loaned transactions require the borrower to deposit cash with the Company. The Company monitors the market value of securities borrowed and loaned on a daily basis, with additional collateral obtained or refunded as necessary.
	Interest is accrued on securities borrowed and loaned transactions and is included in (i) other assets or other liabilities and accrued expenses on the consolidated statements of financial condition and (ii) the respective interest income or interest expense amounts on the consolidated statements of operations.
	Fair Value of Financial Instruments
	Financial instruments and other inventory positions owned and financial instruments and other inventory positions sold, but not yet purchased on the consolidated statements of financial condition consist of financial instruments (including securities with extended settlements and derivative contracts) recorded at fair value. Unrealized gains and losses related to these financial instruments are reflected on the consolidated statements of operations. Securities (both long and short), including securities with extended settlements, are recognized on a trade-date basis. Additionally, certain of the Company’s investments on the consolidated statements of financial condition are recorded at fair value, either as required by accounting guidance or through the fair value election.
	Fair Value Measurement – Definition and Hierarchy – FASB Accounting Standards Codification Topic 820, “Fair Value Measurement,” (“ASC 820”) defines fair value as the amount at which an instrument could be exchanged in an orderly transaction between market participants at the measurement date (the exit price). ASC 820 establishes a fair value hierarchy based on the inputs used to measure fair value. The fair value hierarchy maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that the observable inputs be used when available. Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from independent sources. Unobservable inputs reflect management’s assumptions that market participants would use in pricing the asset or liability developed based on the best information available in the circumstances. The hierarchy is broken down into three levels based on the observability of inputs as follows:
	Level I – Quoted prices (unadjusted) are available in active markets for identical assets or liabilities as of the report date. A quoted price for an identical asset or liability in an active market provides the most reliable fair value measurement because it is directly observable to the market.
	Level II – Pricing inputs are other than quoted prices in active markets, which are either directly or indirectly observable as of the report date. The nature of these financial instruments include instruments for which quoted prices are available but traded less frequently, instruments whose fair value have been derived using a model where inputs to the model are directly observable in the market, or can be derived principally from or corroborated by observable market data, and instruments that are fair valued using other financial instruments, the parameters of which can be directly observed.
	Level III – Instruments that have little to no pricing observability as of the report date. These financial instruments are measured using management’s best estimate of fair value, where the inputs into the determination of fair value require significant management judgment or estimation.
	Valuation of Financial Instruments – Based on the nature of the Company’s business and its role as a “dealer” in the securities industry or its role as a manager of alternative asset management funds, the fair values of its financial instruments are determined internally. When available, the Company values financial instruments at observable market prices, observable market parameters, or broker or dealer prices (bid and ask prices). In the case of financial instruments transacted on recognized exchanges, the observable market prices represent quotations for completed transactions from the exchange on which the financial instrument is principally traded.
	A substantial percentage of the fair value of the Company’s financial instruments and other inventory positions owned and financial instruments and other inventory positions sold, but not yet purchased, are based on observable market prices, observable market parameters, or derived from broker or dealer prices. The availability of observable market prices and pricing parameters can vary from product to product. Where available, observable market prices and pricing or market parameters in a product may be used to derive a price without requiring significant judgment. In certain markets, observable market prices or market parameters are not available for all products, and fair value is determined using techniques appropriate for each particular product. These techniques involve some degree of judgment. Results from valuation models and other techniques in one period may not be indicative of future period fair value measurement.
	For investments in illiquid or privately held securities that do not have readily determinable fair values, the determination of fair value requires the Company to estimate the value of the securities using the best information available. Among the factors considered by the Company in determining the fair value of such financial instruments are the cost, terms and liquidity of the investment, the financial condition and operating results of the issuer, the quoted market price of publicly traded securities with similar quality and yield, and other factors generally pertinent to the valuation of investments. In instances where a security is subject to transfer restrictions, the value of the security is based primarily on the quoted price of a similar security without restriction but may be reduced by an amount estimated to reflect such restrictions. In addition, even where the Company derives the value of a security based on information from an independent source, certain assumptions may be required to determine the security’s fair value. For instance, the Company assumes that the size of positions in securities that the Company holds would not be large enough to affect the quoted price of the securities if the firm sells them, and that any such sale would happen in an orderly manner. The actual value realized upon disposition could be different from the currently estimated fair value.
	Fixed Assets
	Fixed assets include furniture and equipment, software and leasehold improvements. Furniture and equipment and software are depreciated using the straight-line method over estimated useful lives of three to ten years. Leasehold improvements are amortized over their estimated useful life or the life of the lease, whichever is shorter. The Company capitalizes certain costs incurred in connection with internal use software projects and amortizes the amount over the expected useful life of the asset, generally three to seven years.
	Leases
	The Company leases its corporate headquarters and other offices under various non-cancelable leases. The leases require payment of real estate taxes, insurance and common area maintenance, in addition to rent. The terms of the Company’s lease agreements generally range up to twelve years. Some of the leases contain renewal options, escalation clauses, rent-free holidays and operating cost adjustments.
	For leases that contain escalation clauses or rent-free holidays, the Company recognizes the related rent expense on a straight-line basis from the date the Company takes possession of the property to the end of the initial lease term. The Company records any difference between the straight-line rent amounts and amounts payable under the leases as part of other liabilities and accrued expenses.
	Cash or lease incentives received upon entering into certain leases are recognized on a straight-line basis as a reduction of rent expense from the date the Company takes possession of the property or receives the cash to the end of the initial lease term. The Company records the unamortized portion of lease incentives as part of other liabilities and accrued expenses.
	Goodwill and Intangible Assets
	Goodwill represents the fair value of the consideration transferred in excess of the fair value of identifiable net assets at the acquisition date. The recoverability of goodwill is evaluated annually, at a minimum, or on an interim basis if circumstances indicate a possible inability to realize the carrying amount. See Note 14 for additional information on the Company's goodwill impairment testing.
	Intangible assets with determinable lives consist of asset management customer relationships and capital markets customer relationships and non-competition agreements that are amortized over their original estimated useful lives ranging from two to ten years. Indefinite-life intangible assets consist of the ARI trade name. It is not amortized and is evaluated annually, at a minimum, or on an interim basis if events or circumstances indicate a possible inability to realize the carrying amount.
	Investments
	The Company’s proprietary investments include equity investments in private companies and partnerships, investments in public companies, investments in registered mutual funds, warrants of public and private companies and private company debt. Equity investments in private companies are accounted for at fair value, as required by accounting guidance or if the fair value option was elected, or at cost. Investments in partnerships are accounted for under the equity method, which is generally the net asset value. Exchange traded direct equity investments in public companies and registered mutual funds are accounted for at fair value. Company-owned warrants with a cashless exercise option are valued at fair value, while warrants without a cashless exercise option are valued at cost. Private company debt investments are recorded at fair value, as required by accounting guidance, or at amortized cost, net of any unamortized premium or discount.
	Other Assets
	Other assets include net deferred income tax assets, receivables and prepaid expenses. Receivables include fee receivables, accrued interest and loans made to employees, typically in connection with their recruitment. Employee loans are forgiven based on continued employment and are amortized to compensation and benefits expense using the straight-line method over the respective terms of the loans, which generally range from two to five years.
	Revenue Recognition
	Investment Banking – Investment banking revenues, which include underwriting and advisory fees, are recorded when services for the transactions are completed under the terms of each engagement. Expenses associated with such transactions are deferred until the related revenue is recognized or the engagement is otherwise concluded. Investment banking revenues are presented net of related unreimbursed expenses for completed deals. Expenses related to investment banking deals not completed are recognized as non-interest expenses on the consolidated statements of operations.
	Institutional Brokerage – Institutional brokerage revenues include (i) commissions received from customers for the execution of brokerage transactions in listed and over-the-counter (OTC) equity, fixed income and convertible debt securities, which are recorded on a trade-date basis, (ii) trading gains and losses and (iii) fees received by the Company for equity research. The Company permits institutional customers to allocate a portion of their gross commissions to pay for research products and other services provided by third parties. The amounts allocated for those purposes are commonly referred to as soft dollar arrangements. As the Company is not the primary obligor for these arrangements, expenses relating to soft dollars are netted against commission revenues and included in other liabilities and accrued expenses on the consolidated statements of financial condition.
	Asset Management – Asset management fees include revenues the Company receives in connection with management and investment advisory services performed for separately managed accounts and various funds and partnerships. These fees are recognized in the period in which services are provided. Fees are defined in client contracts as either fixed or based on a percentage of portfolio assets under management and may include performance fees. Performance fees are earned when the investment return on assets under management exceeds certain benchmark targets or other performance targets over a specified measurement period (monthly, quarterly or annually). Performance fees, if earned, are generally recognized at the end of the specified measurement period, typically the fourth quarter of the applicable year, or upon client liquidation. Performance fees are recognized as of each reporting date for certain consolidated entities.
	Interest Revenue and Expense – The Company nets interest expense within net revenues to mitigate the effects of fluctuations in interest rates on the Company’s consolidated statements of operations. The Company recognizes contractual interest on financial instruments owned and financial instruments sold, but not yet purchased (excluding derivative instruments), on an accrual basis as a component of interest revenue and expense. The Company accounts for interest related to its short-term and bank syndicated financings and its variable rate senior notes on an accrual basis with related interest recorded as interest expense. In addition, the Company recognizes interest revenue related to its securities borrowed and securities purchased under agreements to resell activities and interest expense related to its securities loaned and securities sold under agreements to repurchase activities on an accrual basis.
	Investment Income – Investment income includes realized and unrealized gains and losses from the Company's merchant banking and other firm investments.
	Stock-based Compensation
	FASB Accounting Standards Codification Topic 718, “Compensation — Stock Compensation,” (“ASC 718”) requires all stock-based compensation to be expensed on the consolidated statements of operations based on the grant date fair value of the award. Compensation expense related to share-based awards that do not require future service are recognized in the year in which the awards were deemed to be earned. Share-based awards that require future service are amortized over the relevant service period net of estimated forfeitures. See Note 24 for additional information on the Company's accounting for stock-based compensation.
	Income Taxes
	The Company files a consolidated U.S. federal income tax return, which includes all of its qualifying subsidiaries. The Company is also subject to income tax in various states and municipalities and those foreign jurisdictions in which we operate. Income taxes are provided for using the asset and liability method. Deferred tax assets and liabilities are recognized for the expected future tax consequences attributable to temporary differences between amounts reported for income tax purposes and financial statement purposes, using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The realization of deferred tax assets is assessed and a valuation allowance is recognized to the extent that it is more likely than not that any portion of a deferred tax asset will not be realized. Tax reserves for uncertain tax positions are recorded in accordance with FASB Accounting Standards Codification Topic 740, “Income Taxes” (“ASC 740”).
	Earnings Per Share
	Basic earnings per common share is computed by dividing net income/(loss) applicable to common shareholders by the weighted average number of common shares outstanding for the period. Net income/(loss) applicable to common shareholders represents net income/(loss) reduced by the allocation of earnings to participating securities. Losses are not allocated to participating securities. Diluted earnings per common share is calculated by adjusting the weighted average outstanding shares to assume conversion of all potentially dilutive stock options.
	Unvested share-based payment awards that contain nonforfeitable rights to dividends or dividend equivalents (whether paid or unpaid) are participating securities and are included in the earnings allocation in the earnings per share calculation under the two-class method. The Company grants restricted stock and restricted stock units as part of its share-based compensation program. Recipients of restricted stock are entitled to receive nonforfeitable dividends during the vesting period, and therefore meet the definition of a participating security. The Company's unvested restricted stock units are not participating securities as recipients are not eligible to receive nonforfeitable dividends.
	Foreign Currency Translation
	The Company consolidates foreign subsidiaries which have designated their local currency as their functional currency. Assets and liabilities of these foreign subsidiaries are translated at year-end rates of exchange. The gains or losses resulting from translating foreign currency financial statements are included in other comprehensive income. Gains or losses resulting from foreign currency transactions are included in net income.
	Contingencies
	The Company is involved in various pending and potential legal proceedings related to its business, including litigation, arbitration and regulatory proceedings. The Company establishes reserves for potential losses to the extent that claims are probable of loss and the amount of the loss can be reasonably estimated. The determination of the outcome and reserve amounts requires significant judgment on the part of management.

Recent_Accounting_Pronouncemen

Recent Accounting Pronouncements	12 Months Ended
	Dec. 31, 2014
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements
	Future Adoption of New Applicable Accounting Standards
	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.
	Consolidation
	In February 2015, the FASB issued ASU No. 2015-02, "Consolidation (Topic 810): Amendments to the Consolidation Analysis" ("ASU 2015-02"). ASU 2015-02 amends ASC 810 through targeted changes to the consolidation guidance for legal entities such as limited partnerships, limited liability corporations and securitization structures. It is effective for annual and interim periods beginning after December 15, 2015. Early adoption is permitted. The Company is evaluating the impact of the amended guidance on its consolidated financial statements.

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 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 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 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 is amortized on a straight-line basis over the original requisite service period of two to five years (a weighted average remaining service period of 2.9 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 business.
	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. Transaction costs of $1.1 million were incurred for the year ended December 31, 2013, and are included in restructuring and integration costs within continuing operations on the consolidated statements of operations.
	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, 2011. 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.
		Year Ended December 31,
	(Dollars in thousands)	2013			2012
	Net revenues	$	541,304		$	535,694
	Net income from continuing operations applicable to Piper Jaffray Companies	$	48,568		$	50,413

Discontinued_Operations

Discontinued Operations	12 Months Ended
	Dec. 31, 2014
Discontinued Operations and Disposal Groups [Abstract]
Discontinued Operations	Discontinued Operations
	The Company's Hong Kong capital markets business ceased operations in 2012. In accordance with the provisions of FASB Accounting Standards Codification Topic 205-20, “Discontinued Operations,” the results from this business, previously reported in the Capital Markets segment, have been classified as discontinued operations for all periods presented.
	The components of discontinued operations for the Hong Kong capital markets business are as follows:
		Year Ended December 31,
	(Dollars in thousands)	2013			2012
	Net revenues	$	—		$	6,635
	Restructuring expenses	—			11,535
	Other expenses	1,197			16,550
	Total non-interest expenses	1,197			28,085
	Loss from discontinued operations before income tax benefit	(1,197		)	(21,450		)
	Income tax benefit	(415		)	(21,069		)
	Loss from discontinued operations, net of tax	$	(782	)	$	(381	)
	In 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. FAMCO's results, previously reported in the Asset Management segment, have been presented as discontinued operations for all periods presented and the related assets and liabilities were classified as held for sale as of December 31, 2012.
	The components of discontinued operations for FAMCO are as follows:
		Year Ended December 31,
	(Dollars in thousands)	2013			2012
	Net revenues	$	1,650		$	5,718
	Goodwill impairment	—			5,508
	Operating expenses	5,057			8,362
	Total non-interest expenses	5,057			13,870
	Loss from discontinued operations before income tax benefit	(3,407		)	(8,152		)
	Income tax benefit	(1,326		)	(2,726		)
	Loss from discontinued operations	(2,081		)	(5,426		)
	Loss on sale, net of tax	(1,876		)	—
	Loss from discontinued operations, net of tax	$	(3,957	)	$	(5,426	)

Financial_Instruments_and_Othe

Financial Instruments and Other Inventory Positions Owned and Financial Instruments and Other Inventory Positions Sold, but Not Yet Purchased	12 Months Ended
	Dec. 31, 2014
Securities Owned and Sold, 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:
		December 31,				December 31,
	(Dollars in thousands)	2014				2013
	Financial instruments and other inventory positions owned:
	Corporate securities:
	Equity securities	$	50,365			$	54,097
	Convertible securities	156,685				80,784
	Fixed income securities	48,651				10,102
	Municipal securities:
	Taxable securities	312,753				232,379
	Tax-exempt securities	559,704				460,865
	Short-term securities	68,717				62,620
	Asset-backed securities	125,065				119,811
	U.S. government agency securities	244,046				304,737
	U.S. government securities	2,549				—
	Derivative contracts	47,826				38,633
	Total financial instruments and other inventory positions owned	1,616,361				1,364,028
	Less noncontrolling interests (1)	(267,742		)		(291,513		)
		$	1,348,619			$	1,072,515
	Financial instruments and other inventory positions sold, but not yet purchased:
	Corporate securities:
	Equity securities	$	154,589			$	69,205
	Fixed income securities	21,460				24,021
	U.S. government agency securities	27,735				120,084
	U.S. government securities	523,527				291,320
	Derivative contracts	10,813				8,203
	Total financial instruments and other inventory positions sold, but not yet purchased	738,124				512,833
	Less noncontrolling interests (2)	(98,669		)		(68,356		)
		$	639,455			$	444,477
	-1	Noncontrolling interests attributable to third party ownership in a consolidated municipal bond fund consist of $123.3 million and $101.8 million of taxable municipal securities, $139.5 million and $183.9 million of tax-exempt municipal securities, and $4.9 million and $5.8 million of derivative contracts as of December 31, 2014 and 2013, respectively.
	-2	Noncontrolling interests attributable to third party ownership in a consolidated municipal bond fund consist of $97.6 million and $67.4 million of U.S. government securities, and $1.1 million and $1.0 million of derivative contracts as of December 31, 2014 and 2013, respectively.
	At December 31, 2014 and 2013, financial instruments and other inventory positions owned in the amount of $1.1 billion 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, treasury futures and exchange-traded options.
	Derivative Contract Financial Instruments
	The Company uses interest rate swaps, interest rate locks, credit default swap index contracts, treasury futures 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)				December 31,				December 31,
	Transaction Type or Hedged Security		Derivative Category		2014				2013
	Customer matched-book		Interest rate derivative contract		$	4,860,302			$	5,310,929
	Trading securities		Interest rate derivative contract		297,250				198,500
	Trading securities		Credit default swap index contract		267,796				299,333
	Trading securities		Equity option derivative contract		19,380				17,090
					$	5,444,728			$	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 gains and losses on the related economically hedged inventory positions are not disclosed below as they are not in qualifying hedging relationships. The following table presents the Company’s unrealized gains/(losses) on derivative instruments:
	(Dollars in thousands)				Year Ended December 31,
	Derivative Category		Operations Category		2014				2013				2012
	Interest rate derivative contract		Investment banking		$	(2,790	)		$	(1,529	)		$	(2,583	)
	Interest rate derivative contract		Institutional brokerage		(1,678		)		(2,511		)		(798		)
	Credit default swap index contract		Institutional brokerage		(1,080		)		(1,522		)		(1,603		)
	Equity option derivative contract		Institutional brokerage		1,037				(646		)		—
					$	(4,511	)		$	(6,208	)		$	(4,984	)
	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
					December 31,						December 31,
	Derivative Category		Financial Condition Location		2014				Financial Condition Location		2014
	Interest rate derivative contract		Financial instruments and other inventory positions owned		$	448,127			Financial instruments and other inventory positions sold,  but not yet purchased		$	433,469
	Credit default swap index contract		Financial instruments and other inventory positions owned		5,808				Financial instruments and other inventory positions sold,  but not yet purchased		5,188
	Equity option derivative contract		Financial instruments and other inventory positions owned		76				Financial instruments and other inventory positions sold,  but not yet purchased		189
					$	454,011					$	438,846
	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 December 31, 2014, the Company had $28.3 million of uncollateralized credit exposure with these counterparties (notional contract amount of $197.8 million), including $16.5 million of uncollateralized credit exposure with one counterparty.

Fair_Value_of_Financial_Instru

Fair Value of Financial Instruments	12 Months Ended
	Dec. 31, 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.
	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 49-947 basis points (“bps”) on spreads over U.S. treasury securities, or models based upon prepayment expectations ranging from 37-460 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, interest rate locks, treasury 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 and partnerships, investments in public companies, investments in registered mutual funds, warrants of public and private companies and private company debt. 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. Investments 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 (e.g., multiples of revenue and earnings before interest, taxes, depreciation and amortization ("EBITDA")) 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 $18.4 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 December 31, 2014 and 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 $2.7 million, $10.6 million and $2.6 million for the years ended December 31, 2014, 2013 and 2012, 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 December 31, 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 - 60%		19.40%
	Short-term securities	Discounted cash flow		Expected recovery rate (% of par) (2)	66 - 94%		91.00%
	Asset-backed securities:
	Collateralized by residential mortgages	Discounted cash flow		Credit default rates (3)	1 - 8%		4.20%
				Prepayment rates (4)	2 - 21%		4.10%
				Loss severity (3)	31 - 95%		70.90%
				Valuation yields (3)	5 - 6%		5.30%
	Derivative contracts:
	Interest rate locks	Discounted cash flow		Premium over the MMD curve (1)	0 - 14 bps		13.2 bps
	Investments at fair value:
	Warrants in public and private companies	Black-Scholes option pricing model		Liquidity discount rates (1)	30 - 40%		30.70%
	Warrants in private companies	Black-Scholes option pricing model		Stock volatility factors of comparable companies (2)	21 - 54%		28.00%
	Equity securities in private companies	Market approach		Revenue multiple (2)	2 - 6 times		4.0 times
				EBITDA multiple (2)	9 - 12 times		9.5 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)	1 - 28 bps		13.6 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 ASC 820 as of December 31, 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	$	39,191		$	11,174		$	—		$	—		$	50,365
	Convertible securities	—			156,685			—			—			156,685
	Fixed income securities	—			48,651			—			—			48,651
	Municipal securities:
	Taxable securities	—			312,753			—			—			312,753
	Tax-exempt securities	—			558,518			1,186			—			559,704
Short-term securities	—			67,997			720			—			68,717
Asset-backed securities	—			316			124,749			—			125,065
U.S. government agency securities	—			244,046			—			—			244,046
U.S. government securities	2,549			—			—			—			2,549
Derivative contracts	76			453,795			140			(406,185		)	47,826
Total financial instruments and other inventory positions owned:	41,816			1,853,935			126,795			(406,185		)	1,616,361
Cash equivalents	1,562			—			—			—			1,562
Investments at fair value	20,704			—			74,165			—			94,869
Total assets	$	64,082		$	1,853,935		$	200,960		$	(406,185	)	$	1,712,792
Liabilities:
Financial instruments and other inventory positions sold, but not yet purchased:
Corporate securities:
Equity securities	$	153,254		$	1,335		$	—		$	—		$	154,589
Fixed income securities	—			21,460			—			—			21,460
U.S. government agency securities	—			27,735			—			—			27,735
U.S. government securities	523,527			—			—			—			523,527
Derivative contracts	189			430,835			7,822			(428,033		)	10,813
Total financial instruments and other inventory positions sold, but not yet purchased:	$	676,970		$	481,365		$	7,822		$	(428,033	)	$	738,124
-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 $201.0 million and $171.9 million, or 11.7 percent and 11.2 percent of financial instruments measured at fair value at December 31, 2014 and 2013, respectively. The value of transfers between levels are recognized at the beginning of the reporting period. There were $3.6 million of transfers of financial assets from Level II to Level III during the year ended December 31, 2014, related to investments for which no recent trade activity was observed and valuation inputs became unobservable. There were no other significant transfers between Level I, Level II or Level III for the year ended December 31, 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:
																								Unrealized gains/
																								(losses) for assets/
	Balance at															Realized			Unrealized			Balance at		liabilities held at
	December 31,									Transfers			Transfers			gains/			gains/			December 31,		December 31,
(Dollars in thousands)	2013			Purchases			Sales			in			out			(losses) (1)			(losses) (1)			2014		2014 (1)
Assets:
Financial instruments and other inventory positions owned:
Corporate securities:
Fixed income securities	$	100		$	—		$	(100	)	$	—		$	—		$	—		$	—		$	—	$	—
Municipal securities:
Tax-exempt securities	1,433			—			—			—			—			—			(247		)	1,186		(247		)
Short-term securities	656			—			(25		)	—			—			6			83			720		83
Asset-backed securities	119,799			154,338			(161,962		)	3,552			—			9,189			(167		)	124,749		1,745
Derivative contracts	691			3,602			—			—			—			(3,602		)	(551		)	140		140
Total financial instruments and other inventory positions owned:	122,679			157,940			(162,087		)	3,552			—			5,593			(882		)	126,795		1,721
Investments at fair value	49,240			21,730			(2,368		)	—			—			2,368			3,195			74,165		3,195
Total assets	$	171,919		$	179,670		$	(164,455	)	$	3,552		$	—		$	7,961		$	2,313		$	200,960	$	4,916
Liabilities:
Financial instruments and other inventory positions sold, but not yet purchased:
Derivative contracts	$	6,643		$	(16,751	)	$	—		$	—		$	—		$	16,751		$	1,179		$	7,822	$	7,822
Total financial instruments and other inventory positions sold, but not yet purchased:	$	6,643		$	(16,751	)	$	—		$	—		$	—		$	16,751		$	1,179		$	7,822	$	7,822
-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 on the consolidated statements of operations.
																								Unrealized gains/
																								(losses) for assets/
	Balance at															Realized			Unrealized			Balance at		liabilities held at
	December 31,									Transfers			Transfers			gains/			gains/			December 31,		December 31,
(Dollars in thousands)	2012			Purchases			Sales			in			out			(losses) (1)			(losses) (1)			2013		2013 (1)
Assets:
Financial instruments and other inventory positions owned:
Corporate securities:
Fixed income securities	$	—		$	100		$	—		$	—		$	—		$	—		$	—		$	100	$	—
Municipal securities:
Tax-exempt securities	1,429			1			—			—			—			—			3			1,433		3
Short-term securities	656			—			—			—			—			—			—			656		—
Asset-backed securities	116,171			227,634			(238,860		)	—			—			17,105			(2,251		)	119,799		1,548
Derivative contracts	827			5			(2,382		)	—			—			2,377			(136		)	691		691
Total financial instruments and other inventory positions owned:	119,083			227,740			(241,242		)	—			—			19,482			(2,384		)	122,679		2,242
Investments at fair value	33,245			16,825			(10,358		)	—			(619		)	5,949			4,198			49,240		4,198
Total assets	$	152,328		$	244,565		$	(251,600	)	$	—		$	(619	)	$	25,431		$	1,814		$	171,919	$	6,440
Liabilities:
Financial instruments and other inventory positions sold, but not yet purchased:
Derivative contracts	$	5,218		$	(5,702	)	$	457		$	—		$	—		$	5,232		$	1,438		$	6,643	$	6,643
Total financial instruments and other inventory positions sold, but not yet purchased:	$	5,218		$	(5,702	)	$	457		$	—		$	—		$	5,232		$	1,438		$	6,643	$	6,643
-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 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.
Non-Recurring Fair Value Measurement
In 2012, the Company recorded a goodwill impairment charge of $5.5 million within discontinued operations representing the residual value of goodwill attributable to FAMCO. The fair value measurement used in the analysis was based on a discounted cash flow model and the anticipated pricing for the sale of FAMCO. The discounted cash flow model was calculated using unobservable inputs, such as operational budgets, strategic plans and other estimates, which are classified as Level III within the fair value hierarchy.

Variable_Interest_Entities

Variable Interest Entities	12 Months Ended
	Dec. 31, 2014
Variable Interest Entity, Not Primary Beneficiary, Disclosures [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.
	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 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 $0.6 billion and $0.8 billion at December 31, 2014 and 2013, respectively. The Company’s exposure to loss from these VIEs is $9.0 million, which is the carrying value of its capital contributions recorded in investments on the consolidated statements of financial condition at December 31, 2014. The Company had no liabilities related to these VIEs at December 31, 2014 and 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 December 31, 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 24 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	12 Months Ended
	Dec. 31, 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:
		December 31,		December 31,
	(Dollars in thousands)	2014		2013
	Receivable arising from unsettled securities transactions	$	52,571	$	59,657
	Deposits paid for securities borrowed	57,572		36,278
	Receivable from clearing organizations	4,933		966
	Deposits with clearing organizations	33,799		20,995
	Securities failed to deliver	1,753		593
	Other	10,381		8,624
		$	161,009	$	127,113
	Amounts payable to brokers, dealers and clearing organizations included:
		December 31,		December 31,
	(Dollars in thousands)	2014		2013
	Payable arising from unsettled securities transactions	$	11,048	$	5,643
	Payable to clearing organizations	5,185		9,462
	Securities failed to receive	2,430		744
	Other	6,901		11,873
		$	25,564	$	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.

Receivables_from_and_Payables_1

Receivables from and Payables to Customers	12 Months Ended
	Dec. 31, 2014
Receivables From Payables To Customers [Abstract]
Receivables From Payables To Customers	Receivables from and Payables to Customers
	Amounts receivable from customers included:
		December 31,		December 31,
	(Dollars in thousands)	2014		2013
	Cash accounts	$	6,135	$	5,013
	Margin accounts	3,523		6,620
	Total receivables	$	9,658	$	11,633
	Securities owned by customers are held as collateral for margin loan receivables. This collateral is not reflected on the consolidated financial statements. Margin loan receivables earn interest at floating interest rates based on prime rates.
	Amounts payable to customers included:
		December 31,		December 31,
	(Dollars in thousands)	2014		2013
	Cash accounts	$	13,172	$	30,499
	Margin accounts	156		2,610
	Total payables	$	13,328	$	33,109
	Payables to customers primarily comprise certain cash balances in customer accounts consisting of customer funds pending settlement of securities transactions and customer funds on deposit. Except for amounts arising from customer short sales, all amounts payable to customers are subject to withdrawal by customers upon their request.

Collateralized_Securities_Tran

Collateralized Securities Transactions	12 Months Ended
	Dec. 31, 2014
Disclosure of Repurchase Agreements [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 the majority of its 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 $369.7 million and $212.4 million at December 31, 2014 and 2013, respectively, of which $338.8 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 December 31, 2014:
		Repurchase		Fair Market
	(Dollars in thousands)	Liabilities		Value		Interest Rate
	Term up to 30 day maturities:
	Asset-backed securities	$	18,586	$	25,632	1.66 - 2.01%
	Term of 30 to 90 day maturities:
	Asset-backed securities	9,097		12,823		1.83 - 1.96%
	On demand maturities:
	U.S. government agency securities	54,293		57,705		0.50 - 0.75%
	U.S. government securities	20,670		21,323		0.35%
		$	102,646	$	117,483
	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 December 31, 2014 and 2013, respectively, as a legal right of offset did not exist. The Company had no outstanding securities lending arrangements as of December 31, 2014 or 2013. See Note 6 for information related to the Company's offsetting of derivative contracts.

Investments

Investments	12 Months Ended
	Dec. 31, 2014
Investments, All Other 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:
		December 31,			December 31,
	(Dollars in thousands)	2014			2013
	Investments at fair value	$	94,869		$	69,930
	Investments at cost	8,214			20,709
	Investments accounted for under the equity method	23,757			21,404
	Total investments	126,840			112,043
	Less investments attributable to noncontrolling interests (1)	(32,563		)	(21,137		)
		$	94,277		$	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 and has concluded that no valuation allowance is needed as it is probable that all contractual principal and interest will be collected.
	At December 31, 2014, investments carried on a cost basis had an estimated fair market value of $13.7 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 EBITDA), and changes in market outlook, 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	12 Months Ended
	Dec. 31, 2014
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Other Assets	Other Assets
	Other assets included:
		December 31,		December 31,
	(Dollars in thousands)	2014		2013
	Net deferred income tax assets	$	45,851	$	36,252
	Fee receivables	23,959		34,415
	Accrued interest receivables	10,061		9,793
	Forgivable loans, net	8,366		7,879
	Prepaid expenses	6,067		5,237
	Other	5,995		8,516
	Total other assets	$	100,299	$	102,092
	See Note 28 for additional details concerning the Company's net deferred income tax assets.

Goodwill_and_Intangible_Assets

Goodwill and Intangible Assets	12 Months Ended
	Dec. 31, 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:
		Capital			Asset
	(Dollars in thousands)	Markets			Management			Total
	Goodwill
	Balance at December 31, 2012	$	—		$	196,844		$	196,844
	Goodwill acquired	13,790			—			13,790
	Balance at December 31, 2013	$	13,790		$	196,844		$	210,634
	Goodwill acquired	—			—			—
	Measurement period adjustment	1,244			—			1,244
	Balance at December 31, 2014	$	15,034		$	196,844		$	211,878
	Intangible assets
	Balance at December 31, 2012	$	—		$	41,258		$	41,258
	Intangible assets acquired	6,665			—			6,665
	Amortization of intangible assets	(1,349		)	(6,644		)	(7,993		)
	Balance at December 31, 2013	$	5,316		$	34,614		$	39,930
	Intangible assets acquired	—			—			—
	Amortization of intangible assets	(2,972		)	(6,300		)	(9,272		)
	Balance at December 31, 2014	$	2,344		$	28,314		$	30,658
	The Company tests goodwill and indefinite-life intangible assets for impairment on an annual basis and on an interim basis when circumstances exist that could indicate possible impairment. The Company tests for impairment at the reporting unit level, which is generally one level below its operating segments. The Company has identified two reporting units: capital markets and asset management. When testing for impairment, the Company has the option to first assess qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount. If, after making an assessment, the Company determines it is not more likely than not that the fair value of a reporting unit is less than its carrying amount, then performing the two-step impairment test is unnecessary. However, if the Company concludes otherwise, then the Company is required to perform the two-step impairment test, which requires management to make judgments in determining what assumptions to use in the calculation. The first step of the process consists of estimating the fair value of the reporting units based on the following factors: a discounted cash flow model using revenue and profit forecasts, the Company’s market capitalization, public company comparables and multiples of recent mergers and acquisitions of similar businesses, if available. The estimated fair values of the reporting units are compared with their carrying values, which includes the allocated goodwill. If the estimated fair value is less than the carrying values, a second step is performed to measure the amount of the impairment loss, if any. An impairment loss is equal to the excess of the carrying amount of goodwill over its fair value.
	The Company completed its annual goodwill impairment analysis as of October 31, 2014 and 2013, and concluded there was no goodwill impairment. In 2012, the Company recorded a non-cash goodwill impairment charge of $5.5 million within discontinued operations. This amount represented the residual value of goodwill attributable to FAMCO.
	The Company also evaluated its intangible assets (indefinite and definite-lived) and concluded there was no impairment in 2014, 2013 and 2012, respectively.
	The addition of goodwill and intangible assets during the year ended December 31, 2013 related to the acquisitions of Seattle-Northwest and Edgeview, as discussed in Note 4. In 2014, the Company recorded a $1.2 million measurement period adjustment to increase goodwill and acquisition-related deferred tax liabilities. Management identified $6.7 million of intangible assets, consisting of customer relationships ($6.0 million) and non-competition agreements ($0.7 million), which will be amortized over a weighted average life of 1.9 years and 3.0 years, respectively.
	Intangible assets with determinable lives consist of asset management customer relationships and capital markets customer relationships and non-competition agreements. The intangible assets are amortized over their original estimated useful lives ranging from two to ten years. The following table summarizes the future aggregate amortization expense of the Company's intangible assets with determinable lives for the years ended:
	(Dollars in thousands)
	2015	$	7,093
	2016	6,219
	2017	5,230
	2018	4,804
	2019	4,452
	Total	$	27,798

Fixed_Assets

Fixed Assets	12 Months Ended
	Dec. 31, 2014
Property, Plant and Equipment [Abstract]
Fixed Assets	Fixed Assets
	The following is a summary of fixed assets:
		December 31,			December 31,
	(Dollars in thousands)	2014			2013
	Furniture and equipment	$	28,669		$	34,980
	Leasehold improvements	23,697			23,478
	Software	13,132			19,967
	Total	65,498			78,425
	Accumulated depreciation and amortization	(47,327		)	(62,311		)
		$	18,171		$	16,114
	For the years ended December 31, 2014, 2013 and 2012, depreciation and amortization of furniture and equipment, leasehold improvements and software from continuing operations totaled $5.3 million, $5.6 million and $6.5 million, respectively, and are included in occupancy and equipment expense on the consolidated statements of operations.

ShortTerm_Financing

Short-Term Financing	12 Months Ended
	Dec. 31, 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
		December 31,		December 31,		December 31,	December 31,
	(Dollars in thousands)	2014		2013		2014	2013
	Commercial paper (secured)	$	238,013	$	280,294	1.48%	1.59%
	Prime broker arrangement	127,754		234,417		0.91%	0.90%
	Bank lines (secured)	12,000		—		1.50%	N/A
	Total short-term financing	$	377,767	$	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 December 31, 2014, the weighted average maturity of CP Series A, CP Series II A and CP Series III A was 77 days, 26 days and 27 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 prime broker financing activities are recorded net of receivables from trading activity. 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 December 31, 2014 consisted of a one-year $250 million committed revolving credit facility with U.S. Bank, N.A., which was renewed in December 2014. 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 18, 2015. The Company pays a nonrefundable commitment fee on the unused portion of the facility on a quarterly basis. At December 31, 2014, the Company had no advances against this line of credit.
	The Company’s uncommitted secured lines at December 31, 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 December 31, 2014, the Company had $12.0 million in advances against these lines of credit.

Variable_Rate_Senior_Notes

Variable Rate Senior Notes (Senior Notes)	12 Months Ended
	Dec. 31, 2014
Senior Notes
Debt Instrument [Line Items]
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 December 31, 2014, the Company was in compliance with all covenants.
	The Notes are recorded at amortized cost. As of December 31, 2014, the carrying value of the Notes approximated fair value.

Bank_Syndicated_Financing

Bank Syndicated Financing (Bank Syndicated Financing [Member])	12 Months Ended
	Dec. 31, 2014
Bank Syndicated Financing [Member]
Debt Instrument [Line Items]
Bank Syndicated Financing	Bank Syndicated Financing
	On December 29, 2010, the Company entered into a three-year Credit Agreement comprised of a $100 million amortizing term loan and a $50 million revolving credit facility. SunTrust Bank was the administrative agent (“Agent”) for the lenders. The outstanding balance and unpaid interest on the Credit Agreement was repaid on November 30, 2012 from the proceeds of the Notes discussed in Note 17.

Legal_Contingencies

Legal Contingencies	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Contingencies, Commitments, and Guarantees	Contingencies, Commitments and Guarantees
	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.
	Litigation-related reserve activity from continuing operations included within other operating expenses resulted in expense of $0.8 million, a benefit of $4.1 million primarily attributable to the receipt of insurance proceeds for the reimbursement of prior legal settlements, and expense of $0.9 million for the years ended December 31, 2014, 2013 and 2012, respectively.
	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 December 31, 2014 are as follows:
	(Dollars in thousands)
	2015	$	12,313
	2016	12,052
	2017	9,958
	2018	9,646
	2019	9,099
	Thereafter	26,463
		$	79,531
	Total minimum rentals to be received from 2015 through 2019 under noncancelable subleases were $7.2 million at December 31, 2014.
	Rental expense, including operating costs and real estate taxes, from continuing operations was $13.8 million, $12.9 million and $13.1 million for the years ended December 31, 2014, 2013 and 2012, respectively.
	Fund Commitments
	As of December 31, 2014, the Company had commitments to invest approximately $37.3 million in limited partnerships that provide financing or make investments in private equity funds. The commitments are estimated to be funded, if called, through the end of the respective investment periods ranging from 2015 to 2018.
	Other Guarantees
	The Company is a member of numerous exchanges and clearinghouses. Under the membership agreements with these entities, members generally are required to guarantee the performance of other members, and if a member becomes unable to satisfy its obligations to the clearinghouse, other members would be required to meet shortfalls. To mitigate these performance risks, the exchanges and clearinghouses often require members to post collateral. In addition, the Company identifies and guarantees certain clearing agents against specified potential losses in connection with providing services to the Company or its affiliates. The Company’s maximum potential liability under these arrangements cannot be quantified. However, management believes the likelihood that the Company would be required to make payments under these arrangements is remote. Accordingly, no liability is recorded in the consolidated financial statements for these arrangements.
	As general partner, Piper Jaffray Investment Management LLC, a wholly-owned subsidiary of the Company, has guaranteed the debts, liabilities and obligations of a municipal bond fund to the extent of the general partner’s assets. Management believes the likelihood that the Company would be required to make payments under this arrangement is remote. Accordingly, no liability is recorded in the consolidated financial statements for this arrangement.
	Concentration of Credit Risk
	The Company provides investment, capital-raising and related services to a diverse group of domestic and foreign customers, including governments, corporations, and institutional and individual investors. The Company’s exposure to credit risk associated with the non-performance of customers in fulfilling their contractual obligations pursuant to securities transactions can be directly impacted by volatile securities markets, credit markets and regulatory changes. This exposure is measured on an individual customer basis and on a group basis for customers that share similar attributes. To alleviate the potential for risk concentrations, counterparty credit limits have been implemented for certain products and are continually monitored in light of changing customer and market conditions.

Restructuring

Restructuring	12 Months Ended
	Dec. 31, 2014
Restructuring and Related Activities [Abstract]
Restructuring	Restructuring
	For the year ended December 31, 2013, the Company incurred pre-tax restructuring charges of $3.6 million from continuing operations. The charge included severance benefits of $2.4 million, $0.5 million for vacating redundant leased office space and $0.7 million for contract termination costs. For the year ended December 31, 2012, the Company incurred pre-tax restructuring-related charges of $3.6 million from continuing operations. The charge included severance benefits of $2.4 million and $1.2 million for the reduction of leased office space.

Shareholders_Equity

Shareholders' Equity	12 Months Ended
	Dec. 31, 2014
Equity [Abstract]
Shareholders' Equity	Shareholders’ Equity
	The certificate of incorporation of Piper Jaffray Companies provides for the issuance of up to 100,000,000 shares of common stock with a par value of $0.01 per share and up to 5,000,000 shares of undesignated preferred stock with a par value of $0.01 per share.
	Common Stock
	The holders of Piper Jaffray Companies common stock are entitled to one vote per share on all matters to be voted upon by the shareholders. Subject to preferences that may be applicable to any outstanding preferred stock of Piper Jaffray Companies, the holders of its common stock are entitled to receive ratably such dividends, if any, as may be declared from time to time by the Piper Jaffray Companies board of directors out of funds legally available for that purpose. Piper Jaffray Companies does not currently pay cash dividends on its common stock. Additionally, there are dividend restrictions as set forth in Note 27.
	In the event that Piper Jaffray Companies is liquidated or dissolved, the holders of its common stock are entitled to share ratably in all assets remaining after payment of liabilities, subject to any prior distribution rights of Piper Jaffray Companies preferred stock, if any, then outstanding. Currently, there is no outstanding preferred stock. The holders of the common stock have no preemptive or conversion rights or other subscription rights. There are no redemption or sinking fund provisions applicable to Piper Jaffray Companies common stock.
	During the year ended December 31, 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 774,194 common shares out of treasury stock as a result of employee restricted share vesting and exercise transactions as discussed in Note 24. During the year ended December 31, 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 786,467 common shares out of treasury stock as a result of employee restricted share vesting.
	In the third quarter of 2010, the Company’s board of directors authorized the repurchase of up to $75.0 million in common shares through September 30, 2012. During the nine months ended September 30, 2012, the Company repurchased 1,488,881 shares of the Company’s common stock at an average price of $22.48 per share for an aggregate purchase price of $33.5 million related to this authorization. This share repurchase authorization expired as of September 30, 2012.
	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 fourth quarter of 2012, the Company repurchased 156,577 shares of the Company's common stock at an average price of $29.38 per share for an aggregate purchase price of $4.6 million related to this authorization. During the year ended December 31, 2013, the Company repurchased 1,719,662 shares at an average price of $32.52 per share for an aggregate purchase price of $55.9 million related to this authorization. During the nine months ended September 30, 2014, the Company did not repurchase any shares of the Company’s outstanding common stock related to this authorization. This share repurchase authorization expired as of September 30, 2014.
	Effective October 1, 2014, the Company's board of directors authorized the repurchase of up to $100.0 million in common shares through September 30, 2016. During the fourth quarter of 2014, the Company did not repurchase any shares of the Company’s outstanding common stock related to 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 256,055 shares or $10.9 million, 386,713 shares or $15.5 million and 385,449 shares or $9.1 million of the Company’s common stock for this purpose during the years ended December 31, 2014, 2013 and 2012, respectively.
	Preferred Stock
	The Piper Jaffray Companies board of directors has the authority, without action by its shareholders, to designate and issue preferred stock in one or more series and to designate the rights, preferences and privileges of each series, which may be greater than the rights associated with the common stock. It is not possible to state the actual effect of the issuance of any shares of preferred stock upon the rights of holders of common stock until the Piper Jaffray Companies board of directors determines the specific rights of the holders of preferred stock. However, the effects might include, among other things, the following: restricting dividends on its common stock, diluting the voting power of its common stock, impairing the liquidation rights of its common stock and delaying or preventing a change in control of Piper Jaffray Companies without further action by its shareholders.

Noncontrolling_Interests

Noncontrolling Interests	12 Months Ended
	Dec. 31, 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 $117.0 million, a merchant banking fund of $24.7 million and private equity investment vehicles aggregating $7.8 million as of December 31, 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 years ended December 31, 2014, 2013 and 2012.

Employee_Benefit_Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2014
Compensation and Retirement Disclosure [Abstract]
Employee Benefit Plans	Employee Benefit Plans
	The Company has various employee benefit plans, and substantially all employees are covered by at least one plan. The plans include health and welfare plans and a tax-qualified retirement plan (the “Retirement Plan”). During the years ended December 31, 2014, 2013 and 2012, the Company incurred employee benefits expenses from continuing operations of $13.2 million, $12.1 million and $13.0 million, respectively.
	Health and Welfare Plans
	Company employees who meet certain work schedule and service requirements are eligible to participate in the Company’s health and welfare plans. The Company subsidizes the cost of coverage for employees. The health plans contain cost-sharing features such as deductibles and coinsurance.
	The Company is self-insured for losses related to health claims, although it obtains third-party stop loss insurance coverage on both an individual and a group plan basis. Self-insured liabilities are based on a number of factors, including historical claims experience, an estimate of claims incurred but not reported and valuations provided by third-party actuaries. For the years ended December 31, 2014, 2013 and 2012, the Company recognized expense of $7.7 million, $7.2 million and $8.0 million, respectively, in compensation and benefits expense from continuing operations on the consolidated statements of operations related to its health plans.
	Retirement Plan
	The Retirement Plan consists of a defined contribution retirement savings plan. The defined contribution retirement savings plan allows qualified employees, at their option, to make contributions through salary deductions under Section 401(k) of the Internal Revenue Code. Employee contributions are 100 percent matched by the Company to a maximum of six percent of recognized compensation up to the social security taxable wage base. Although the Company’s matching contribution vests immediately, a participant must be employed on December 31 to receive that year’s matching contribution.

Compensation_Plans

Compensation Plans	12 Months Ended
	Dec. 31, 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 December 31, 2014:
	Incentive Plan
	Restricted Stock
	Annual grants	806,162
	Sign-on grants	259,984
		1,066,146
	Inducement Plan
	Restricted Stock	29,159
	Total restricted stock outstanding	1,095,305
	Incentive Plan
	Restricted Stock Units
	Leadership grants	405,826
	Incentive Plan
	Stock options outstanding	217,873
	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 (1.0 million shares remained available for future issuance under the Incentive Plan as of December 31, 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 also 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 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 2014 for its February 2015 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 $28.2 million, $21.0 million and $20.2 million for the years ended December 31, 2014, 2013 and 2012, 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 and Leadership Grants, less forfeitures of $0.7 million, $1.0 million and $1.3 million for the years ended December 31, 2014, 2013 and 2012, respectively. The tax benefit related to stock-based compensation costs totaled $11.0 million, $8.2 million and $7.9 million for the years ended December 31, 2014, 2013 and 2012, respectively.
	The following table summarizes the changes in the Company’s unvested restricted stock under the Incentive Plan and Inducement Plan:
		Unvested		Weighted Average
		Restricted Stock		Grant Date
		(in Shares)		Fair Value
	December 31, 2011	3,152,001		$	38.79
	Granted	635,136		22.89
	Vested	(1,309,881	)	34.21
	Canceled	(154,818	)	39.37
	December 31, 2012	2,322,438		$	37.01
	Granted	682,760		38.35
	Vested	(1,165,989	)	39.83
	Canceled	(257,147	)	38.3
	December 31, 2013	1,582,062		$	35.25
	Granted	421,728		40.57
	Vested	(883,761	)	36.22
	Canceled	(24,724	)	36.02
	December 31, 2014	1,095,305		$	36.51
	The fair value of restricted stock that vested during the years ended December 31, 2014, 2013 and 2012 was $32.0 million, $46.4 million and $44.8 million, respectively.
	The following table summarizes the changes in the Company’s unvested restricted stock units under the Incentive Plan:
		Unvested		Weighted Average
		Restricted		Grant Date
		Stock Units		Fair Value
	December 31, 2011	—		$	—
	Granted	214,526		12.12
	Vested	—		—
Canceled	(41,255	)	12.12
December 31, 2012	173,271		$	12.12
Granted	117,265		21.32
Vested	—		—
Canceled	—		—
December 31, 2013	290,536		$	15.83
Granted	115,290		23.42
Vested	—		—
Canceled	—		—
December 31, 2014	405,826		$	17.99
As of December 31, 2014, there was $10.2 million of total unrecognized compensation cost related to restricted stock and restricted stock units expected to be recognized over a weighted average period of 2.4 years.
The following table summarizes the changes in the Company’s outstanding stock options:
						Weighted Average
			Weighted			Remaining
	Options		Average			Contractual Term	Aggregate
	Outstanding		Exercise Price			(in Years)	Intrinsic Value
31-Dec-11	502,623		$	44.71		3.9	$	—
Granted	—		—
Exercised	—		—
Canceled	(16,060	)	43.17
31-Dec-12	486,563		$	44.76		2.9	$	94,150
Granted	—		—
Exercised	—		—
Canceled	(17,274	)	42.85
December 31, 2013	469,289		$	44.83		2	$	288,318
Granted	—		—
Exercised	(137,864	)	39.55
Canceled	(55	)	39.62
Expired	(113,497	)	47.72
December 31, 2014	217,873		$	46.66		2	$	3,066,839
Options exercisable at December 31, 2012	486,563		$	44.76		2.9	$	94,150
Options exercisable at December 31, 2013	469,289		$	44.83		2	$	288,318
Options exercisable at December 31, 2014	217,873		$	46.66		2	$	3,066,839
Additional information regarding Piper Jaffray Companies options outstanding as of December 31, 2014 is as follows:
		Options Outstanding						Exercisable Options
				Weighted Average
				Remaining	Weighted				Weighted
Range of				Contractual	Average				Average
Exercise Prices		Shares		Life (in Years)	Exercise Price			Shares	Exercise Price
$28.01		11,426		0.3	$	28.01		11,426	$	28.01
$33.40		4,001		0.6	$	33.4		4,001	$	33.4
$39.62		44,543		0.1	$	39.62		44,543	$	39.62
$41.09		99,147		3.1	$	41.09		99,147	$	41.09
$47.30 - $51.05		11,343		1.1	$	47.85		11,343	$	47.85
$70.13 - $70.65		47,413		1.9	$	70.26		47,413	$	70.26
As of December 31, 2014, there was no unrecognized compensation cost related to stock options expected to be recognized over future years.
The intrinsic value of options exercised and the resulting tax benefit realized was $1.7 million and $0.7 million, respectively, for the year ended December 31, 2014. There were no options exercised for the years ended December 31, 2013 and 2012.
The Company has a policy of issuing shares out of treasury (to the extent available) to satisfy share option exercises and restricted stock vesting. The Company expects to withhold approximately 0.2 million shares from employee equity awards vesting in 2015, related to employee individual income tax withholding obligations on restricted stock vesting. For accounting purposes, withholding shares to cover employees’ tax obligations is deemed to be a repurchase of shares by the Company.
Deferred Compensation Plans
The Company maintains various deferred compensation arrangements for employees.
The nonqualified deferred compensation plan is 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 $6.6 million as of December 31, 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 $6.6 million as of December 31, 2014. Changes in the fair value of the investments made by the Company are reported in investment income and changes in the corresponding deferred compensation liability are reflected as compensation and benefits expense on the consolidated statements of operations.
The Piper Jaffray Companies Mutual Fund Restricted Share Investment Plan is 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	12 Months Ended
	Dec. 31, 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:
		Year Ended December 31,
	(Amounts in thousands, except per share data)	2014			2013			2012
	Net income from continuing operations applicable to Piper Jaffray Companies	$	63,172		$	49,829		$	47,075
	Net loss from discontinued operations	—			(4,739		)	(5,807		)
	Net income applicable to Piper Jaffray Companies	63,172			45,090			41,268
	Earnings allocated to participating securities (1)	(5,031		)	(4,494		)	(5,933		)
	Net income applicable to Piper Jaffray Companies’ common shareholders (2)	$	58,141		$	40,596		$	35,335
	Shares for basic and diluted calculations:
	Average shares used in basic computation	14,971			15,046			15,615
	Stock options	54			15			1
	Average shares used in diluted computation	15,025			15,061			15,616
	Earnings/(loss) per basic common share:
	Income from continuing operations	$	3.88		$	2.98		$	2.58
	Loss from discontinued operations	—			(0.28		)	(0.32		)
	Earnings per basic common share	$	3.88		$	2.7		$	2.26
	Earnings/(loss) per diluted common share:
	Income from continuing operations	$	3.87		$	2.98		$	2.58
	Loss from discontinued operations	—			(0.28		)	(0.32		)
	Earnings per diluted common share	$	3.87		$	2.7		$	2.26
	-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 1,299,827; 1,667,067 and 2,622,438 for the years ended December 31, 2014, 2013 and 2012, 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 years ended December 31, 2014, 2013 and 2012.

Segment_Reporting

Segment Reporting	12 Months Ended
	Dec. 31, 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:
		Year Ended December 31,
	(Dollars in thousands)	2014			2013			2012
	Capital Markets
	Investment banking
	Financing
	Equities	$	116,684		$	100,224		$	73,180
	Debt	67,731			74,284			74,102
	Advisory services	186,176			74,420			86,165
	Total investment banking	370,591			248,928			233,447
	Institutional sales and trading
	Equities	82,211			91,169			75,723
	Fixed income	92,200			76,275			111,492
	Total institutional sales and trading	174,411			167,444			187,215
	Management and performance fees	5,398			3,891			1,678
	Investment income	24,046			30,404			9,840
	Long-term financing expenses	(6,655		)	(7,420		)	(7,982		)
	Net revenues	567,791			443,247			424,198
	Operating expenses (1)	478,661			393,231			371,628
	Segment pre-tax operating income	$	89,130		$	50,016		$	52,570
	Segment pre-tax operating margin	15.7		%	11.3		%	12.4		%
		Year Ended December 31,
	(Dollars in thousands)	2014			2013			2012
	Asset Management
	Management and performance fees
	Management fees	$	78,772		$	71,314		$	63,236
	Performance fees	892			7,840			785
	Total management and performance fees	79,664			79,154			64,021
	Investment income	683			2,794			733
	Net revenues	80,347			81,948			64,754
	Operating expenses (1)	59,166			56,351			48,313
	Segment pre-tax operating income	$	21,181		$	25,597		$	16,441
	Segment pre-tax operating margin	26.4		%	31.2		%	25.4		%
	Total
	Net revenues	$	648,138		$	525,195		$	488,952
	Operating expenses (1)	537,827			449,582			419,941
	Pre-tax operating income	$	110,311		$	75,613		$	69,011
	Pre-tax operating margin	17		%	14.4		%	14.1		%
	-1	Operating expenses include intangible asset amortization expense as set forth in the table below:
		Year Ended December 31,
	(Dollars in thousands)	2014			2013			2012
	Capital Markets	$	2,972		$	1,349		$	—
	Asset Management	6,300			6,644			6,944
	Total intangible asset amortization expense	$	9,272		$	7,993		$	6,944
	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.
		Year Ended December 31,
	(Dollars in thousands)	2014			2013			2012
	Net revenues:
	United States	$	632,625		$	513,433		$	476,718
	Europe	15,513			11,762			12,234
	Consolidated	$	648,138		$	525,195		$	488,952
	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:
		December 31,			December 31,
	(Dollars in thousands)	2014			2013
	Long-lived assets:
	United States	$	300,421		$	296,516
	Europe	5,516			6,414
	Consolidated	$	305,937		$	302,930

Net_Capital_Requirements_and_O

Net Capital Requirements and Other Regulatory Matters	12 Months Ended
	Dec. 31, 2014
Regulatory Capital Requirements [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 December 31, 2014, net capital calculated under the SEC rule was $165.3 million, and exceeded the minimum net capital required under the SEC rule by $164.3 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 December 31, 2014, Piper Jaffray Ltd. was in compliance with the capital requirements of the Prudential Regulation Authority and the Financial Conduct Authority.

Income_Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes
	Income tax expense is provided using the asset and liability method. Deferred tax assets and liabilities are recognized for the expected future tax consequences attributable to temporary differences between amounts reported for income tax purposes and financial statement purposes, using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled.
	The components of income tax expense from continuing operations are as follows:
		Year Ended December 31,
	(Dollars in thousands)	2014			2013			2012
	Current:
	Federal	$	37,331		$	20,468		$	16,939
	State	8,117			3,795			(9,563		)
	Foreign	161			183			—
		45,609			24,446			7,376
	Deferred:
	Federal	(8,641		)	(1,582		)	7,735
	State	(1,317		)	(4,041		)	4,413
	Foreign	335			1,567			(54		)
		(9,623		)	(4,056		)	12,094
	Total income tax expense from continuing operations	$	35,986		$	20,390		$	19,470
	Total income tax benefit from discontinued operations	$	—		$	(2,935	)	$	(23,795	)
	A reconciliation of federal income taxes at statutory rates to the Company’s effective tax rates from continuing operations is as follows:
		Year Ended December 31,
	(Dollars in thousands)	2014			2013			2012
	Federal income tax expense at statutory rates	$	38,609		$	26,464		$	24,153
	Increase/(reduction) in taxes resulting from:
	State income taxes, net of federal tax benefit	3,857			2,785			2,540
	Net tax-exempt interest income	(3,693		)	(3,917		)	(3,353		)
	Foreign jurisdictions tax rate differential	(63		)	(185		)	(164		)
	Change in valuation allowance	—			(4,182		)	(1,110		)
	Restricted stock deferred tax asset write-off	—			—			4,577
	Income attributable to noncontrolling interests	(3,903		)	(1,888		)	(863		)
	Other, net	1,179			1,313			(6,310		)
	Total income tax expense from continuing operations	$	35,986		$	20,390		$	19,470
	In accordance with ASC 740, U.S. income taxes are not provided on undistributed earnings of international subsidiaries that are permanently reinvested. As of December 31, 2014, undistributed earnings permanently reinvested in the Company’s foreign subsidiaries were not material.
	Deferred income tax assets and liabilities reflect the tax effect of temporary differences between the carrying amount of assets and liabilities for financial reporting purposes and the amounts used for the same items for income tax reporting purposes. The net deferred income tax assets included in other assets on the consolidated statements of financial condition consisted of the following items:
		December 31,			December 31,
	(Dollars in thousands)	2014			2013
	Deferred tax assets:
	Deferred compensation	$	56,893		$	43,608
	Net operating loss carry forwards	4,854			5,569
	Liabilities/accruals not currently deductible	1,601			1,903
	Other	2,930			1,459
	Total deferred tax assets	66,278			52,539
	Valuation allowance	(159		)	(159		)
	Deferred tax assets after valuation allowance	66,119			52,380
	Deferred tax liabilities:
	Goodwill amortization	15,028			9,957
	Unrealized gains on firm investments	3,221			3,577
	Fixed assets	945			1,017
	Other	1,074			1,577
	Total deferred tax liabilities	20,268			16,128
	Net deferred tax assets	$	45,851		$	36,252
	The realization of deferred tax assets is assessed and a valuation allowance is recorded to the extent that it is more likely than not that any portion of the deferred tax asset will not be realized. The Company believes that its future tax profits will be sufficient to recognize its deferred tax assets, with the exception of $0.2 million in state net operating loss carryforwards.
	The Company accounts for unrecognized tax benefits in accordance with the provisions of ASC 740, which requires tax reserves to be recorded for uncertain tax positions on the consolidated statements of financial condition. A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows:
	(Dollars in thousands)
	Balance at December 31, 2011	$	8,915
	Additions based on tax positions related to the current year	—
	Additions for tax positions of prior years	200
	Reductions for tax positions of prior years	(8,825		)
	Settlements	—
	Balance at December 31, 2012	$	290
	Additions based on tax positions related to the current year	—
	Additions for tax positions of prior years	2,000
	Reductions for tax positions of prior years	(90		)
	Settlements	—
	Balance at December 31, 2013	$	2,200
	Additions based on tax positions related to the current year	—
Additions for tax positions of prior years	123
Reductions for tax positions of prior years	—
Settlements	—
Balance at December 31, 2014	$	2,323
As of December 31, 2014, approximately $0.3 million of the Company's unrecognized tax benefits would impact the annual effective rate, if recognized.
In 2012, the Company reversed $8.8 million for unrecognized tax benefits. In addition, the Company reversed $2.6 million of accrued interest related to these positions. In aggregate, the Company recorded a $7.4 million credit to income tax expense in 2012, net of federal income tax.
The Company recognizes interest and penalties accrued related to unrecognized tax benefits as a component of income tax expense. The Company had approximately $0.2 million for the payment of interest and penalties accrued at December 31, 2014 and 2013, respectively, which was recognized during the year ended December 31, 2013. During the year ended December 31, 2012, the Company recognized no interest and penalties. The Company or one of its subsidiaries files income tax returns with the various states and foreign jurisdictions in which the Company operates. The Company is not subject to U.S. federal tax authorities for years before 2011 and is not subject to state and local or non-U.S. tax authorities for taxable years before 2009. The Company anticipates all of its uncertain income tax provisions will be resolved within the next twelve months.

Piper_Jaffray_Companies_Parent

Piper Jaffray Companies (Parent Company only)	12 Months Ended
	Dec. 31, 2014
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Condensed Financial Information of Parent Company Only Disclosure [Text Block]	Piper Jaffray Companies (Parent Company only)
	Condensed Statements of Financial Condition
		December 31,			December 31,
	(Amounts in thousands)	2014			2013
	Assets
	Cash and cash equivalents	$	200		$	336
	Investment in and advances to subsidiaries	956,609			870,104
	Other assets	13,819			9,119
	Total assets	$	970,628		$	879,559
	Liabilities and Shareholders’ Equity
	Variable rate senior notes	$	125,000		$	125,000
	Accrued compensation	24,618			18,454
	Other liabilities and accrued expenses	1,098			1,429
	Total liabilities	150,716			144,883
	Shareholders’ equity	819,912			734,676
	Total liabilities and shareholders’ equity	$	970,628		$	879,559
	Condensed Statements of Operations
		Year Ended December 31,
	(Amounts in thousands)	2014			2013			2012
	Revenues:
	Dividends from subsidiaries	$	50,333		$	46,000		$	119,000
	Interest	662			254			82
	Other revenues	275			198			—
	Total revenues	51,270			46,452			119,082
	Interest expense	5,463			5,850			5,823
	Net revenues	45,807			40,602			113,259
	Non-interest expenses:
	Total non-interest expenses	5,318			3,096			4,222
	Income from continuing operations before income tax expense and equity in undistributed/(distributed in excess of) income of subsidiaries	40,489			37,506			109,037
	Income tax expense	14,795			13,263			39,175
	Income from continuing operations of parent company	25,694			24,243			69,862
	Equity in undistributed/(distributed in excess of) income of subsidiaries	37,478			25,200			(49,617		)
	Net income from continuing operations	63,172			49,443			20,245
	Discontinued operations:
	Income/(loss) from discontinued operations, net of tax	—			(4,353		)	21,023
	Net income	$	63,172		$	45,090		$	41,268
	Condensed Statements of Cash Flows
		Year Ended December 31,
	(Amounts in thousands)	2014			2013			2012
	Operating Activities:
	Net income	$	63,172		$	45,090		$	41,268
	Adjustments to reconcile net income to net cash provided by operating activities:
	Share-based and deferred compensation	180			60			240
	Equity distributed in excess of/(in undistributed) income of subsidiaries	(37,478		)	(25,200		)	49,617
	Net cash provided by operating activities	25,874			19,950			91,125
	Investing Activities:
	Repayment of FAMCO note	2,000			250			—
	Net cash provided by investing activities	2,000			250			—
	Financing Activities:
	Issuance of variable rate senior notes	50,000			—			125,000
	Repayment of variable rate senior notes	(50,000		)	—			—
	Decrease in bank syndicated financing	—			—			(115,000		)
	Advances from/(to) subsidiaries	(28,010		)	34,996			(76,481		)
	Repurchase of common stock	—			(55,929		)	(38,068		)
	Net cash used in financing activities	(28,010		)	(20,933		)	(104,549		)
	Net decrease in cash and cash equivalents	(136		)	(733		)	(13,424		)
	Cash and cash equivalents at beginning of year	336			1,069			14,493
	Cash and cash equivalents at end of year	$	200		$	336		$	1,069
	Supplemental disclosures of cash flow information
	Cash paid during the year for:
	Interest	$	(4,801	)	$	(5,596	)	$	(5,741	)
	Income taxes	$	(14,795	)	$	(13,263	)	$	(39,175	)

Quarterly_Information_unaudite

Quarterly Information (unaudited)	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Quarterly Information (unaudited)	Quarterly Information (unaudited)
		2014 Fiscal Quarter
	(Amounts in thousands, except per share data)		First			Second			Third			Fourth
	Total revenues		$	173,894		$	175,976		$	165,947		$	157,394
	Interest expense		5,761			5,945			6,521			6,846
	Net revenues		168,133			170,031			159,426			150,548
	Non-interest expenses		135,420			139,614			133,734			129,059
	Income from continuing operations before income tax expense		32,713			30,417			25,692			21,489
	Income tax expense		9,827			10,049			8,596			7,514
	Net income from continuing operations		22,886			20,368			17,096			13,975
	Loss from discontinued operations, net of tax		—			—			—			—
	Net income		22,886			20,368			17,096			13,975
	Net income applicable to noncontrolling interests		5,138			2,155			2,428			1,432
	Net income applicable to Piper Jaffray Companies		$	17,748		$	18,213		$	14,668		12,543
	Net income applicable to Piper Jaffray Companies' common shareholders		$	16,089		$	16,717		$	13,552		$	11,700
	Amounts applicable to Piper Jaffray Companies
	Net income from continuing operations		$	17,748		$	18,213		$	14,668		$	12,543
	Net loss from discontinued operations		—			—			—			—
	Net income applicable to Piper Jaffray Companies		$	17,748		$	18,213		$	14,668		$	12,543
	Earnings per basic common share
	Income from continuing operations		$	1.1		$	1.12		$	0.9		$	0.77
	Loss from discontinued operations		—			—			—			—
	Earnings per basic common share		$	1.1		$	1.12		$	0.9		$	0.77
	Earnings per diluted common share
	Income from continuing operations		$	1.1		$	1.11		$	0.9		$	0.77
	Loss from discontinued operations		—			—			—			—
	Earnings per diluted common share		$	1.1		$	1.11		$	0.9		$	0.77
	Weighted average number of common shares
	Basic		14,612			14,958			15,066			15,241
	Diluted		14,657			15,013			15,129			15,293
		2013 Fiscal Quarter
	(Amounts in thousands, except per share data)		First			Second			Third			Fourth
	Total revenues		$	115,312		$	106,520		$	134,506		$	193,893
	Interest expense		5,779			6,748			6,192			6,317
	Net revenues		109,533			99,772			128,314			187,576
	Non-interest expenses		91,365			96,439			116,254			145,524
	Income from continuing operations before income tax expense		18,168			3,333			12,060			42,052
	Income tax expense		5,600			1,644			2,886			10,260
	Net income from continuing operations		12,568			1,689			9,174			31,792
	Loss from discontinued operations, net of tax		(521		)	(1,871		)	(1,529		)	(818		)
	Net income/(loss)		12,047			(182		)	7,645			30,974
	Net income/(loss) applicable to noncontrolling interests		1,901			(2,670		)	2,323			3,840
	Net income applicable to Piper Jaffray Companies		$	10,146		$	2,488		$	5,322		$	27,134
	Net income applicable to Piper Jaffray Companies' common shareholders		$	8,966		$	2,266		$	4,826		$	24,445
	Amounts applicable to Piper Jaffray Companies
	Net income from continuing operations		$	10,667		$	4,359		$	6,851		$	27,952
	Loss from discontinued operations		(521		)	(1,871		)	(1,529		)	(818		)
	Net income applicable to Piper Jaffray Companies		$	10,146		$	2,488		$	5,322		$	27,134
	Earnings per basic common share
	Income from continuing operations		$	0.6		$	0.25		$	0.42		$	1.75
	Loss from discontinued operations		(0.03		)	(0.11		)	(0.09		)	(0.05		)
	Earnings per basic common share		$	0.58		$	0.15		$	0.33		$	1.7
	Earnings per diluted common share
	Income from continuing operations		$	0.6		$	0.25		$	0.42		$	1.75
	Loss from discontinued operations		(0.03		)	(0.11		)	(0.09		)	(0.05		)
	Earnings per diluted common share		$	0.57		$	0.15		$	0.33		$	1.7
	Weighted average number of common shares
	Basic		15,582			15,621			14,641			14,378
	Diluted		15,610			15,626			14,626			14,397

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation
	The Company determines whether it has a controlling financial interest in an entity by first evaluating whether the entity is a voting interest entity or a variable interest entity (“VIE”).
	Voting interest entities are entities in which (i) the total equity investment at risk is sufficient to enable each entity to finance itself independently and (ii) the equity holders have the obligation to absorb losses, the right to receive residual returns and the right or power to make decisions about or direct the entity’s activities that most significantly impact the entity’s economic performance. Financial Accounting Standards Board (“FASB”) Accounting Standards Codification Topic 810, “Consolidations,” (“ASC 810”) states that the usual condition for a controlling financial interest in a voting interest entity is ownership of a majority voting interest. Accordingly, the Company consolidates voting interest entities in which it has all, or a majority of, the voting interests.
	VIEs are entities that lack one or more of the characteristics of a voting interest entity. With the exception of entities eligible for the deferral codified in FASB Accounting Standards Update (“ASU”) No. 2010-10, “Consolidation: Amendments for Certain Investment Funds,” (“ASU 2010-10”) (generally asset managers and investment companies), ASC 810 states that a controlling financial interest in a VIE is present when an enterprise has one or more variable interests that have both (i) the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance and (ii) the obligation to absorb losses of the entity or the rights to receive benefits from the VIE that could potentially be significant to the VIE. Accordingly, the Company consolidates VIEs in which the Company has a controlling financial interest.
	Entities meeting the deferral provision defined by ASU 2010-10 are evaluated under the historical VIE guidance. Under the historical guidance, a controlling financial interest in an entity is present when an enterprise has one or more variable interests that will absorb a majority of the entity’s expected losses, receive a majority of the entity’s expected residual returns, or both. The enterprise with a controlling financial interest is the primary beneficiary and consolidates the VIE. Accordingly, the Company consolidates VIEs subject to the deferral provisions defined by ASU 2010-10 in which the Company is deemed to be the primary beneficiary.
	When the Company does not have a controlling financial interest in an entity but exerts significant influence over the entity’s operating and financial policies (generally defined as owning a voting or economic interest of between 20 percent to 50 percent), the Company's investment is accounted for under the equity method of accounting. The Company accounts for its investments in partnerships under the equity method of accounting. If the Company does not have a controlling financial interest in, or exert significant influence over, an entity, the Company accounts for its investment at fair value, if the fair value option was elected, or at cost.
Cash and Cash Equivalents	Cash and Cash Equivalents
	Cash and cash equivalents consist of cash and highly liquid investments with maturities of 90 days or less at the date of origination.
	In accordance with Rule 15c3-3 of the Securities Exchange Act of 1934, Piper Jaffray, as a registered broker dealer carrying customer accounts, is subject to requirements related to maintaining cash or qualified securities in a segregated reserve account for the exclusive benefit of its customers.
Customer Transactions	Customer Transactions
	Customer securities transactions are recorded on a settlement date basis, while the related revenues and expenses are recorded on a trade-date basis. Customer receivables and payables include amounts related to both cash and margin transactions. Securities owned by customers, including those that collateralize margin or other similar transactions, are not reflected on the consolidated statements of financial condition.
Receivables from and Payables to Brokers, Dealers, and Clearing Organizations	Receivables from and Payables to Brokers, Dealers and Clearing Organizations
	Receivables from brokers, dealers and clearing organizations include receivables arising from unsettled securities transactions, deposits paid for securities borrowed, receivables from clearing organizations, deposits with clearing organizations and amounts receivable for securities not delivered to the purchaser by the settlement date (“securities failed to deliver”). Payables to brokers, dealers and clearing organizations include payables arising from unsettled securities transactions, payables to clearing organizations and amounts payable for securities not received from a seller by the settlement date (“securities failed to receive”). Unsettled securities transactions related to the Company's broker dealer operations are recorded at contract value on a net basis. Unsettled securities transactions related to the Company's consolidated investment company operations are recorded on a gross basis.
Collateralzied Securities Transactions	Collateralized Securities Transactions
	Securities purchased under agreements to resell and securities sold under agreements to repurchase are carried at the contractual amounts at which the securities will be subsequently resold or repurchased, including accrued interest. It is the Company’s policy to take possession or control of securities purchased under agreements to resell at the time these agreements are entered into. The counterparties to these agreements typically are primary dealers of U.S. government securities and major financial institutions. Collateral is valued daily, and additional collateral is obtained from or refunded to counterparties when appropriate.
	Securities borrowed and loaned result from transactions with other broker dealers or financial institutions and are recorded at the amount of cash collateral advanced or received. These amounts are included in receivables from and payables to brokers, dealers and clearing organizations on the consolidated statements of financial condition. Securities borrowed transactions require the Company to deposit cash or other collateral with the lender. Securities loaned transactions require the borrower to deposit cash with the Company. The Company monitors the market value of securities borrowed and loaned on a daily basis, with additional collateral obtained or refunded as necessary.
	Interest is accrued on securities borrowed and loaned transactions and is included in (i) other assets or other liabilities and accrued expenses on the consolidated statements of financial condition and (ii) the respective interest income or interest expense amounts on the consolidated statements of operations.
Fair Value of Financial Instruments	Fair Value of Financial Instruments
	Financial instruments and other inventory positions owned and financial instruments and other inventory positions sold, but not yet purchased on the consolidated statements of financial condition consist of financial instruments (including securities with extended settlements and derivative contracts) recorded at fair value. Unrealized gains and losses related to these financial instruments are reflected on the consolidated statements of operations. Securities (both long and short), including securities with extended settlements, are recognized on a trade-date basis. Additionally, certain of the Company’s investments on the consolidated statements of financial condition are recorded at fair value, either as required by accounting guidance or through the fair value election.
	Fair Value Measurement – Definition and Hierarchy – FASB Accounting Standards Codification Topic 820, “Fair Value Measurement,” (“ASC 820”) defines fair value as the amount at which an instrument could be exchanged in an orderly transaction between market participants at the measurement date (the exit price). ASC 820 establishes a fair value hierarchy based on the inputs used to measure fair value. The fair value hierarchy maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that the observable inputs be used when available. Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from independent sources. Unobservable inputs reflect management’s assumptions that market participants would use in pricing the asset or liability developed based on the best information available in the circumstances. The hierarchy is broken down into three levels based on the observability of inputs as follows:
	Level I – Quoted prices (unadjusted) are available in active markets for identical assets or liabilities as of the report date. A quoted price for an identical asset or liability in an active market provides the most reliable fair value measurement because it is directly observable to the market.
	Level II – Pricing inputs are other than quoted prices in active markets, which are either directly or indirectly observable as of the report date. The nature of these financial instruments include instruments for which quoted prices are available but traded less frequently, instruments whose fair value have been derived using a model where inputs to the model are directly observable in the market, or can be derived principally from or corroborated by observable market data, and instruments that are fair valued using other financial instruments, the parameters of which can be directly observed.
	Level III – Instruments that have little to no pricing observability as of the report date. These financial instruments are measured using management’s best estimate of fair value, where the inputs into the determination of fair value require significant management judgment or estimation.
	Valuation of Financial Instruments – Based on the nature of the Company’s business and its role as a “dealer” in the securities industry or its role as a manager of alternative asset management funds, the fair values of its financial instruments are determined internally. When available, the Company values financial instruments at observable market prices, observable market parameters, or broker or dealer prices (bid and ask prices). In the case of financial instruments transacted on recognized exchanges, the observable market prices represent quotations for completed transactions from the exchange on which the financial instrument is principally traded.
	A substantial percentage of the fair value of the Company’s financial instruments and other inventory positions owned and financial instruments and other inventory positions sold, but not yet purchased, are based on observable market prices, observable market parameters, or derived from broker or dealer prices. The availability of observable market prices and pricing parameters can vary from product to product. Where available, observable market prices and pricing or market parameters in a product may be used to derive a price without requiring significant judgment. In certain markets, observable market prices or market parameters are not available for all products, and fair value is determined using techniques appropriate for each particular product. These techniques involve some degree of judgment. Results from valuation models and other techniques in one period may not be indicative of future period fair value measurement.
	For investments in illiquid or privately held securities that do not have readily determinable fair values, the determination of fair value requires the Company to estimate the value of the securities using the best information available. Among the factors considered by the Company in determining the fair value of such financial instruments are the cost, terms and liquidity of the investment, the financial condition and operating results of the issuer, the quoted market price of publicly traded securities with similar quality and yield, and other factors generally pertinent to the valuation of investments. In instances where a security is subject to transfer restrictions, the value of the security is based primarily on the quoted price of a similar security without restriction but may be reduced by an amount estimated to reflect such restrictions. In addition, even where the Company derives the value of a security based on information from an independent source, certain assumptions may be required to determine the security’s fair value. For instance, the Company assumes that the size of positions in securities that the Company holds would not be large enough to affect the quoted price of the securities if the firm sells them, and that any such sale would happen in an orderly manner. The actual value realized upon disposition could be different from the currently estimated fair value.
Fixed Assets	Fixed Assets
	Fixed assets include furniture and equipment, software and leasehold improvements. Furniture and equipment and software are depreciated using the straight-line method over estimated useful lives of three to ten years. Leasehold improvements are amortized over their estimated useful life or the life of the lease, whichever is shorter. The Company capitalizes certain costs incurred in connection with internal use software projects and amortizes the amount over the expected useful life of the asset, generally three to seven years.
Leases	Leases
	The Company leases its corporate headquarters and other offices under various non-cancelable leases. The leases require payment of real estate taxes, insurance and common area maintenance, in addition to rent. The terms of the Company’s lease agreements generally range up to twelve years. Some of the leases contain renewal options, escalation clauses, rent-free holidays and operating cost adjustments.
	For leases that contain escalation clauses or rent-free holidays, the Company recognizes the related rent expense on a straight-line basis from the date the Company takes possession of the property to the end of the initial lease term. The Company records any difference between the straight-line rent amounts and amounts payable under the leases as part of other liabilities and accrued expenses.
	Cash or lease incentives received upon entering into certain leases are recognized on a straight-line basis as a reduction of rent expense from the date the Company takes possession of the property or receives the cash to the end of the initial lease term. The Company records the unamortized portion of lease incentives as part of other liabilities and accrued expenses.
Goodwill and Intangible Assets	Goodwill and Intangible Assets
	Goodwill represents the fair value of the consideration transferred in excess of the fair value of identifiable net assets at the acquisition date. The recoverability of goodwill is evaluated annually, at a minimum, or on an interim basis if circumstances indicate a possible inability to realize the carrying amount. See Note 14 for additional information on the Company's goodwill impairment testing.
	Intangible assets with determinable lives consist of asset management customer relationships and capital markets customer relationships and non-competition agreements that are amortized over their original estimated useful lives ranging from two to ten years. Indefinite-life intangible assets consist of the ARI trade name. It is not amortized and is evaluated annually, at a minimum, or on an interim basis if events or circumstances indicate a possible inability to realize the carrying amount.
Investments	Investments
	The Company’s proprietary investments include equity investments in private companies and partnerships, investments in public companies, investments in registered mutual funds, warrants of public and private companies and private company debt. Equity investments in private companies are accounted for at fair value, as required by accounting guidance or if the fair value option was elected, or at cost. Investments in partnerships are accounted for under the equity method, which is generally the net asset value. Exchange traded direct equity investments in public companies and registered mutual funds are accounted for at fair value. Company-owned warrants with a cashless exercise option are valued at fair value, while warrants without a cashless exercise option are valued at cost. Private company debt investments are recorded at fair value, as required by accounting guidance, or at amortized cost, net of any unamortized premium or discount.
Other Assets	Other Assets
	Other assets include net deferred income tax assets, receivables and prepaid expenses. Receivables include fee receivables, accrued interest and loans made to employees, typically in connection with their recruitment. Employee loans are forgiven based on continued employment and are amortized to compensation and benefits expense using the straight-line method over the respective terms of the loans, which generally range from two to five years.
Revenue Recognition	Revenue Recognition
	Investment Banking – Investment banking revenues, which include underwriting and advisory fees, are recorded when services for the transactions are completed under the terms of each engagement. Expenses associated with such transactions are deferred until the related revenue is recognized or the engagement is otherwise concluded. Investment banking revenues are presented net of related unreimbursed expenses for completed deals. Expenses related to investment banking deals not completed are recognized as non-interest expenses on the consolidated statements of operations.
	Institutional Brokerage – Institutional brokerage revenues include (i) commissions received from customers for the execution of brokerage transactions in listed and over-the-counter (OTC) equity, fixed income and convertible debt securities, which are recorded on a trade-date basis, (ii) trading gains and losses and (iii) fees received by the Company for equity research. The Company permits institutional customers to allocate a portion of their gross commissions to pay for research products and other services provided by third parties. The amounts allocated for those purposes are commonly referred to as soft dollar arrangements. As the Company is not the primary obligor for these arrangements, expenses relating to soft dollars are netted against commission revenues and included in other liabilities and accrued expenses on the consolidated statements of financial condition.
	Asset Management – Asset management fees include revenues the Company receives in connection with management and investment advisory services performed for separately managed accounts and various funds and partnerships. These fees are recognized in the period in which services are provided. Fees are defined in client contracts as either fixed or based on a percentage of portfolio assets under management and may include performance fees. Performance fees are earned when the investment return on assets under management exceeds certain benchmark targets or other performance targets over a specified measurement period (monthly, quarterly or annually). Performance fees, if earned, are generally recognized at the end of the specified measurement period, typically the fourth quarter of the applicable year, or upon client liquidation. Performance fees are recognized as of each reporting date for certain consolidated entities.
	Interest Revenue and Expense – The Company nets interest expense within net revenues to mitigate the effects of fluctuations in interest rates on the Company’s consolidated statements of operations. The Company recognizes contractual interest on financial instruments owned and financial instruments sold, but not yet purchased (excluding derivative instruments), on an accrual basis as a component of interest revenue and expense. The Company accounts for interest related to its short-term and bank syndicated financings and its variable rate senior notes on an accrual basis with related interest recorded as interest expense. In addition, the Company recognizes interest revenue related to its securities borrowed and securities purchased under agreements to resell activities and interest expense related to its securities loaned and securities sold under agreements to repurchase activities on an accrual basis.
	Investment Income – Investment income includes realized and unrealized gains and losses from the Company's merchant banking and other firm investments.
Stock-based Compensation	Stock-based Compensation
	FASB Accounting Standards Codification Topic 718, “Compensation — Stock Compensation,” (“ASC 718”) requires all stock-based compensation to be expensed on the consolidated statements of operations based on the grant date fair value of the award. Compensation expense related to share-based awards that do not require future service are recognized in the year in which the awards were deemed to be earned. Share-based awards that require future service are amortized over the relevant service period net of estimated forfeitures. See Note 24 for additional information on the Company's accounting for stock-based compensation.
Income Taxes	Income Taxes
	The Company files a consolidated U.S. federal income tax return, which includes all of its qualifying subsidiaries. The Company is also subject to income tax in various states and municipalities and those foreign jurisdictions in which we operate. Income taxes are provided for using the asset and liability method. Deferred tax assets and liabilities are recognized for the expected future tax consequences attributable to temporary differences between amounts reported for income tax purposes and financial statement purposes, using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The realization of deferred tax assets is assessed and a valuation allowance is recognized to the extent that it is more likely than not that any portion of a deferred tax asset will not be realized. Tax reserves for uncertain tax positions are recorded in accordance with FASB Accounting Standards Codification Topic 740, “Income Taxes” (“ASC 740”).
Earnings Per Share	Earnings Per Share
	Basic earnings per common share is computed by dividing net income/(loss) applicable to common shareholders by the weighted average number of common shares outstanding for the period. Net income/(loss) applicable to common shareholders represents net income/(loss) reduced by the allocation of earnings to participating securities. Losses are not allocated to participating securities. Diluted earnings per common share is calculated by adjusting the weighted average outstanding shares to assume conversion of all potentially dilutive stock options.
	Unvested share-based payment awards that contain nonforfeitable rights to dividends or dividend equivalents (whether paid or unpaid) are participating securities and are included in the earnings allocation in the earnings per share calculation under the two-class method. The Company grants restricted stock and restricted stock units as part of its share-based compensation program. Recipients of restricted stock are entitled to receive nonforfeitable dividends during the vesting period, and therefore meet the definition of a participating security. The Company's unvested restricted stock units are not participating securities as recipients are not eligible to receive nonforfeitable dividends.
Foreign Currency Translation	Foreign Currency Translation
	The Company consolidates foreign subsidiaries which have designated their local currency as their functional currency. Assets and liabilities of these foreign subsidiaries are translated at year-end rates of exchange. The gains or losses resulting from translating foreign currency financial statements are included in other comprehensive income. Gains or losses resulting from foreign currency transactions are included in net income.
Contingencies	Contingencies
	The Company is involved in various pending and potential legal proceedings related to its business, including litigation, arbitration and regulatory proceedings. The Company establishes reserves for potential losses to the extent that claims are probable of loss and the amount of the loss can be reasonably estimated. The determination of the outcome and reserve amounts requires significant judgment on the part of management.

Acquisitions_Tables

Acquisitions (Tables)	12 Months Ended
	Dec. 31, 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
		Year Ended December 31,
	(Dollars in thousands)	2013			2012
	Net revenues	$	541,304		$	535,694
	Net income from continuing operations applicable to Piper Jaffray Companies	$	48,568		$	50,413

Discontinued_Operations_Tables

Discontinued Operations (Tables)	12 Months Ended
	Dec. 31, 2014
Hong Kong Capital Markets
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Schedule of Disposal Groups, Including Discontinued Operations, Income Statement	The components of discontinued operations for the Hong Kong capital markets business are as follows:
		Year Ended December 31,
	(Dollars in thousands)	2013			2012
	Net revenues	$	—		$	6,635
	Restructuring expenses	—			11,535
	Other expenses	1,197			16,550
	Total non-interest expenses	1,197			28,085
	Loss from discontinued operations before income tax benefit	(1,197		)	(21,450		)
	Income tax benefit	(415		)	(21,069		)
	Loss from discontinued operations, net of tax	$	(782	)	$	(381	)
FAMCO
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Schedule of Disposal Groups, Including Discontinued Operations, Income Statement	The components of discontinued operations for FAMCO are as follows:
		Year Ended December 31,
	(Dollars in thousands)	2013			2012
	Net revenues	$	1,650		$	5,718
	Goodwill impairment	—			5,508
	Operating expenses	5,057			8,362
	Total non-interest expenses	5,057			13,870
	Loss from discontinued operations before income tax benefit	(3,407		)	(8,152		)
	Income tax benefit	(1,326		)	(2,726		)
	Loss from discontinued operations	(2,081		)	(5,426		)
	Loss on sale, net of tax	(1,876		)	—
	Loss from discontinued operations, net of tax	$	(3,957	)	$	(5,426	)

Financial_Instruments_and_Othe1

Financial Instruments and Other Inventory Positions Owned and Financial Instruments and Other Inventory Positions Sold, but Not Yet Purchased (Tables)	12 Months Ended
	Dec. 31, 2014
Securities Owned and Sold, 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:
		December 31,				December 31,
	(Dollars in thousands)	2014				2013
	Financial instruments and other inventory positions owned:
	Corporate securities:
	Equity securities	$	50,365			$	54,097
	Convertible securities	156,685				80,784
	Fixed income securities	48,651				10,102
	Municipal securities:
	Taxable securities	312,753				232,379
	Tax-exempt securities	559,704				460,865
	Short-term securities	68,717				62,620
	Asset-backed securities	125,065				119,811
	U.S. government agency securities	244,046				304,737
	U.S. government securities	2,549				—
	Derivative contracts	47,826				38,633
	Total financial instruments and other inventory positions owned	1,616,361				1,364,028
	Less noncontrolling interests (1)	(267,742		)		(291,513		)
		$	1,348,619			$	1,072,515
	Financial instruments and other inventory positions sold, but not yet purchased:
	Corporate securities:
	Equity securities	$	154,589			$	69,205
	Fixed income securities	21,460				24,021
	U.S. government agency securities	27,735				120,084
	U.S. government securities	523,527				291,320
	Derivative contracts	10,813				8,203
	Total financial instruments and other inventory positions sold, but not yet purchased	738,124				512,833
	Less noncontrolling interests (2)	(98,669		)		(68,356		)
		$	639,455			$	444,477
	-1	Noncontrolling interests attributable to third party ownership in a consolidated municipal bond fund consist of $123.3 million and $101.8 million of taxable municipal securities, $139.5 million and $183.9 million of tax-exempt municipal securities, and $4.9 million and $5.8 million of derivative contracts as of December 31, 2014 and 2013, respectively.
	-2	Noncontrolling interests attributable to third party ownership in a consolidated municipal bond fund consist of $97.6 million and $67.4 million of U.S. government securities, and $1.1 million and $1.0 million of derivative contracts as of December 31, 2014 and 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)				December 31,				December 31,
	Transaction Type or Hedged Security		Derivative Category		2014				2013
	Customer matched-book		Interest rate derivative contract		$	4,860,302			$	5,310,929
	Trading securities		Interest rate derivative contract		297,250				198,500
	Trading securities		Credit default swap index contract		267,796				299,333
	Trading securities		Equity option derivative contract		19,380				17,090
					$	5,444,728			$	5,825,852
Unrealized Gains/(Losses) on Derivative Instruments	The gains and losses on the related economically hedged inventory positions are not disclosed below as they are not in qualifying hedging relationships. The following table presents the Company’s unrealized gains/(losses) on derivative instruments:
	(Dollars in thousands)				Year Ended December 31,
	Derivative Category		Operations Category		2014				2013				2012
	Interest rate derivative contract		Investment banking		$	(2,790	)		$	(1,529	)		$	(2,583	)
	Interest rate derivative contract		Institutional brokerage		(1,678		)		(2,511		)		(798		)
	Credit default swap index contract		Institutional brokerage		(1,080		)		(1,522		)		(1,603		)
	Equity option derivative contract		Institutional brokerage		1,037				(646		)		—
					$	(4,511	)		$	(6,208	)		$	(4,984	)
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
					December 31,						December 31,
	Derivative Category		Financial Condition Location		2014				Financial Condition Location		2014
	Interest rate derivative contract		Financial instruments and other inventory positions owned		$	448,127			Financial instruments and other inventory positions sold,  but not yet purchased		$	433,469
	Credit default swap index contract		Financial instruments and other inventory positions owned		5,808				Financial instruments and other inventory positions sold,  but not yet purchased		5,188
	Equity option derivative contract		Financial instruments and other inventory positions owned		76				Financial instruments and other inventory positions sold,  but not yet purchased		189
					$	454,011					$	438,846

Fair_Value_of_Financial_Instru1

Fair Value of Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 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 December 31, 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 - 60%		19.40%
	Short-term securities	Discounted cash flow		Expected recovery rate (% of par) (2)	66 - 94%		91.00%
	Asset-backed securities:
	Collateralized by residential mortgages	Discounted cash flow		Credit default rates (3)	1 - 8%		4.20%
				Prepayment rates (4)	2 - 21%		4.10%
				Loss severity (3)	31 - 95%		70.90%
				Valuation yields (3)	5 - 6%		5.30%
	Derivative contracts:
	Interest rate locks	Discounted cash flow		Premium over the MMD curve (1)	0 - 14 bps		13.2 bps
	Investments at fair value:
	Warrants in public and private companies	Black-Scholes option pricing model		Liquidity discount rates (1)	30 - 40%		30.70%
	Warrants in private companies	Black-Scholes option pricing model		Stock volatility factors of comparable companies (2)	21 - 54%		28.00%
	Equity securities in private companies	Market approach		Revenue multiple (2)	2 - 6 times		4.0 times
				EBITDA multiple (2)	9 - 12 times		9.5 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)	1 - 28 bps		13.6 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 ASC 820 as of December 31, 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	$	39,191		$	11,174		$	—		$	—		$	50,365
	Convertible securities	—			156,685			—			—			156,685
	Fixed income securities	—			48,651			—			—			48,651
	Municipal securities:
	Taxable securities	—			312,753			—			—			312,753
	Tax-exempt securities	—			558,518			1,186			—			559,704
	Short-term securities	—			67,997			720			—			68,717
	Asset-backed securities	—			316			124,749			—			125,065
	U.S. government agency securities	—			244,046			—			—			244,046
	U.S. government securities	2,549			—			—			—			2,549
	Derivative contracts	76			453,795			140			(406,185		)	47,826
	Total financial instruments and other inventory positions owned:	41,816			1,853,935			126,795			(406,185		)	1,616,361
	Cash equivalents	1,562			—			—			—			1,562
	Investments at fair value	20,704			—			74,165			—			94,869
	Total assets	$	64,082		$	1,853,935		$	200,960		$	(406,185	)	$	1,712,792
	Liabilities:
	Financial instruments and other inventory positions sold, but not yet purchased:
	Corporate securities:
	Equity securities	$	153,254		$	1,335		$	—		$	—		$	154,589
	Fixed income securities	—			21,460			—			—			21,460
	U.S. government agency securities	—			27,735			—			—			27,735
	U.S. government securities	523,527			—			—			—			523,527
	Derivative contracts	189			430,835			7,822			(428,033		)	10,813
	Total financial instruments and other inventory positions sold, but not yet purchased:	$	676,970		$	481,365		$	7,822		$	(428,033	)	$	738,124
	-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:
																									Unrealized gains/
																									(losses) for assets/
		Balance at															Realized			Unrealized			Balance at		liabilities held at
		December 31,									Transfers			Transfers			gains/			gains/			December 31,		December 31,
	(Dollars in thousands)	2013			Purchases			Sales			in			out			(losses) (1)			(losses) (1)			2014		2014 (1)
	Assets:
	Financial instruments and other inventory positions owned:
	Corporate securities:
	Fixed income securities	$	100		$	—		$	(100	)	$	—		$	—		$	—		$	—		$	—	$	—
	Municipal securities:
	Tax-exempt securities	1,433			—			—			—			—			—			(247		)	1,186		(247		)
	Short-term securities	656			—			(25		)	—			—			6			83			720		83
	Asset-backed securities	119,799			154,338			(161,962		)	3,552			—			9,189			(167		)	124,749		1,745
	Derivative contracts	691			3,602			—			—			—			(3,602		)	(551		)	140		140
	Total financial instruments and other inventory positions owned:	122,679			157,940			(162,087		)	3,552			—			5,593			(882		)	126,795		1,721
	Investments at fair value	49,240			21,730			(2,368		)	—			—			2,368			3,195			74,165		3,195
	Total assets	$	171,919		$	179,670		$	(164,455	)	$	3,552		$	—		$	7,961		$	2,313		$	200,960	$	4,916
	Liabilities:
	Financial instruments and other inventory positions sold, but not yet purchased:
	Derivative contracts	$	6,643		$	(16,751	)	$	—		$	—		$	—		$	16,751		$	1,179		$	7,822	$	7,822
	Total financial instruments and other inventory positions sold, but not yet purchased:	$	6,643		$	(16,751	)	$	—		$	—		$	—		$	16,751		$	1,179		$	7,822	$	7,822
	-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 on the consolidated statements of operations.
																									Unrealized gains/
																									(losses) for assets/
		Balance at															Realized			Unrealized			Balance at		liabilities held at
		December 31,									Transfers			Transfers			gains/			gains/			December 31,		December 31,
	(Dollars in thousands)	2012			Purchases			Sales			in			out			(losses) (1)			(losses) (1)			2013		2013 (1)
	Assets:
	Financial instruments and other inventory positions owned:
	Corporate securities:
	Fixed income securities	$	—		$	100		$	—		$	—		$	—		$	—		$	—		$	100	$	—
	Municipal securities:
	Tax-exempt securities	1,429			1			—			—			—			—			3			1,433		3
	Short-term securities	656			—			—			—			—			—			—			656		—
	Asset-backed securities	116,171			227,634			(238,860		)	—			—			17,105			(2,251		)	119,799		1,548
	Derivative contracts	827			5			(2,382		)	—			—			2,377			(136		)	691		691
	Total financial instruments and other inventory positions owned:	119,083			227,740			(241,242		)	—			—			19,482			(2,384		)	122,679		2,242
	Investments at fair value	33,245			16,825			(10,358		)	—			(619		)	5,949			4,198			49,240		4,198
	Total assets	$	152,328		$	244,565		$	(251,600	)	$	—		$	(619	)	$	25,431		$	1,814		$	171,919	$	6,440
	Liabilities:
	Financial instruments and other inventory positions sold, but not yet purchased:
	Derivative contracts	$	5,218		$	(5,702	)	$	457		$	—		$	—		$	5,232		$	1,438		$	6,643	$	6,643
	Total financial instruments and other inventory positions sold, but not yet purchased:	$	5,218		$	(5,702	)	$	457		$	—		$	—		$	5,232		$	1,438		$	6,643	$	6,643
	-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 on the consolidated statements of operations

Receivables_from_and_Payables_2

Receivables from and Payables to Brokers, Dealers and Clearing Organizations (Tables)	12 Months Ended
	Dec. 31, 2014
Brokers and Dealers [Abstract]
Schedule of Due to (from) Broker-Dealers and Clearing Organizations [Table Text Block]	Amounts receivable from brokers, dealers and clearing organizations included:
		December 31,		December 31,
	(Dollars in thousands)	2014		2013
	Receivable arising from unsettled securities transactions	$	52,571	$	59,657
	Deposits paid for securities borrowed	57,572		36,278
	Receivable from clearing organizations	4,933		966
	Deposits with clearing organizations	33,799		20,995
	Securities failed to deliver	1,753		593
	Other	10,381		8,624
		$	161,009	$	127,113
	Amounts payable to brokers, dealers and clearing organizations included:
		December 31,		December 31,
	(Dollars in thousands)	2014		2013
	Payable arising from unsettled securities transactions	$	11,048	$	5,643
	Payable to clearing organizations	5,185		9,462
	Securities failed to receive	2,430		744
	Other	6,901		11,873
		$	25,564	$	27,722

Receivables_from_and_Payables_3

Receivables from and Payables to Customers (Tables)	12 Months Ended
	Dec. 31, 2014
Receivables From Payables To Customers [Abstract]
Schedule Of Receivable From Customer Table	Amounts receivable from customers included:
		December 31,		December 31,
	(Dollars in thousands)	2014		2013
	Cash accounts	$	6,135	$	5,013
	Margin accounts	3,523		6,620
	Total receivables	$	9,658	$	11,633
Schedule Of Payables To Customer Table	Amounts payable to customers included:
		December 31,		December 31,
	(Dollars in thousands)	2014		2013
	Cash accounts	$	13,172	$	30,499
	Margin accounts	156		2,610
	Total payables	$	13,328	$	33,109

Collateralized_Securities_Tran1

Collateralized Securities Transactions (Tables)	12 Months Ended
	Dec. 31, 2014
Disclosure of Repurchase Agreements [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 December 31, 2014:
		Repurchase		Fair Market
	(Dollars in thousands)	Liabilities		Value		Interest Rate
	Term up to 30 day maturities:
	Asset-backed securities	$	18,586	$	25,632	1.66 - 2.01%
	Term of 30 to 90 day maturities:
	Asset-backed securities	9,097		12,823		1.83 - 1.96%
	On demand maturities:
	U.S. government agency securities	54,293		57,705		0.50 - 0.75%
	U.S. government securities	20,670		21,323		0.35%
		$	102,646	$	117,483

Investments_Tables

Investments (Tables)	12 Months Ended
	Dec. 31, 2014
Investments, All Other 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:
		December 31,			December 31,
	(Dollars in thousands)	2014			2013
	Investments at fair value	$	94,869		$	69,930
	Investments at cost	8,214			20,709
	Investments accounted for under the equity method	23,757			21,404
	Total investments	126,840			112,043
	Less investments attributable to noncontrolling interests (1)	(32,563		)	(21,137		)
		$	94,277		$	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)	12 Months Ended
	Dec. 31, 2014
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Other Assets	Other assets included:
		December 31,		December 31,
	(Dollars in thousands)	2014		2013
	Net deferred income tax assets	$	45,851	$	36,252
	Fee receivables	23,959		34,415
	Accrued interest receivables	10,061		9,793
	Forgivable loans, net	8,366		7,879
	Prepaid expenses	6,067		5,237
	Other	5,995		8,516
	Total other assets	$	100,299	$	102,092

Goodwill_and_Intangible_Assets1

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 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:
		Capital			Asset
	(Dollars in thousands)	Markets			Management			Total
	Goodwill
	Balance at December 31, 2012	$	—		$	196,844		$	196,844
	Goodwill acquired	13,790			—			13,790
	Balance at December 31, 2013	$	13,790		$	196,844		$	210,634
	Goodwill acquired	—			—			—
	Measurement period adjustment	1,244			—			1,244
	Balance at December 31, 2014	$	15,034		$	196,844		$	211,878
	Intangible assets
	Balance at December 31, 2012	$	—		$	41,258		$	41,258
	Intangible assets acquired	6,665			—			6,665
	Amortization of intangible assets	(1,349		)	(6,644		)	(7,993		)
	Balance at December 31, 2013	$	5,316		$	34,614		$	39,930
	Intangible assets acquired	—			—			—
	Amortization of intangible assets	(2,972		)	(6,300		)	(9,272		)
	Balance at December 31, 2014	$	2,344		$	28,314		$	30,658
Schedule of Expected Amortization Expense	The following table summarizes the future aggregate amortization expense of the Company's intangible assets with determinable lives for the years ended:
	(Dollars in thousands)
	2015	$	7,093
	2016	6,219
	2017	5,230
	2018	4,804
	2019	4,452
	Total	$	27,798

Fixed_Assets_Tables

Fixed Assets (Tables)	12 Months Ended
	Dec. 31, 2014
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	The following is a summary of fixed assets:
		December 31,			December 31,
	(Dollars in thousands)	2014			2013
	Furniture and equipment	$	28,669		$	34,980
	Leasehold improvements	23,697			23,478
	Software	13,132			19,967
	Total	65,498			78,425
	Accumulated depreciation and amortization	(47,327		)	(62,311		)
		$	18,171		$	16,114

ShortTerm_Financing_Tables

Short-Term Financing (Tables)	12 Months Ended
	Dec. 31, 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
		December 31,		December 31,		December 31,	December 31,
	(Dollars in thousands)	2014		2013		2014	2013
	Commercial paper (secured)	$	238,013	$	280,294	1.48%	1.59%
	Prime broker arrangement	127,754		234,417		0.91%	0.90%
	Bank lines (secured)	12,000		—		1.50%	N/A
	Total short-term financing	$	377,767	$	514,711

Contingencies_Commitments_and_

Contingencies, Commitments and Guarantees (Tables)	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Rental Payments for Operating Leases	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 December 31, 2014 are as follows:
	(Dollars in thousands)
	2015	$	12,313
	2016	12,052
	2017	9,958
	2018	9,646
	2019	9,099
	Thereafter	26,463
		$	79,531

Compensation_Plans_Tables

Compensation Plans (Tables)	12 Months Ended
	Dec. 31, 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 December 31, 2014:
	Incentive Plan
	Restricted Stock
	Annual grants	806,162
	Sign-on grants	259,984
		1,066,146
	Inducement Plan
	Restricted Stock	29,159
	Total restricted stock outstanding	1,095,305
	Incentive Plan
	Restricted Stock Units
	Leadership grants	405,826
	Incentive Plan
	Stock options outstanding	217,873
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 under the Incentive Plan and Inducement Plan:
		Unvested		Weighted Average
		Restricted Stock		Grant Date
		(in Shares)		Fair Value
	December 31, 2011	3,152,001		$	38.79
	Granted	635,136		22.89
	Vested	(1,309,881	)	34.21
	Canceled	(154,818	)	39.37
	December 31, 2012	2,322,438		$	37.01
	Granted	682,760		38.35
	Vested	(1,165,989	)	39.83
	Canceled	(257,147	)	38.3
	December 31, 2013	1,582,062		$	35.25
	Granted	421,728		40.57
	Vested	(883,761	)	36.22
	Canceled	(24,724	)	36.02
	December 31, 2014	1,095,305		$	36.51
Changes in Unvested Restricted Stock Units	The following table summarizes the changes in the Company’s unvested restricted stock units under the Incentive Plan:
		Unvested		Weighted Average
		Restricted		Grant Date
		Stock Units		Fair Value
	December 31, 2011	—		$	—
	Granted	214,526		12.12
	Vested	—		—
	Canceled	(41,255	)	12.12
	December 31, 2012	173,271		$	12.12
	Granted	117,265		21.32
	Vested	—		—
	Canceled	—		—
	December 31, 2013	290,536		$	15.83
	Granted	115,290		23.42
	Vested	—		—
	Canceled	—		—
	December 31, 2014	405,826		$	17.99
Changes in Outstanding Stock Options	The following table summarizes the changes in the Company’s outstanding stock options:
							Weighted Average
				Weighted			Remaining
		Options		Average			Contractual Term	Aggregate
		Outstanding		Exercise Price			(in Years)	Intrinsic Value
	31-Dec-11	502,623		$	44.71		3.9	$	—
	Granted	—		—
	Exercised	—		—
	Canceled	(16,060	)	43.17
	31-Dec-12	486,563		$	44.76		2.9	$	94,150
	Granted	—		—
	Exercised	—		—
	Canceled	(17,274	)	42.85
	December 31, 2013	469,289		$	44.83		2	$	288,318
	Granted	—		—
	Exercised	(137,864	)	39.55
	Canceled	(55	)	39.62
	Expired	(113,497	)	47.72
	December 31, 2014	217,873		$	46.66		2	$	3,066,839
	Options exercisable at December 31, 2012	486,563		$	44.76		2.9	$	94,150
	Options exercisable at December 31, 2013	469,289		$	44.83		2	$	288,318
	Options exercisable at December 31, 2014	217,873		$	46.66		2	$	3,066,839
Schedule of Additional Information Option Outstanding	Additional information regarding Piper Jaffray Companies options outstanding as of December 31, 2014 is as follows:
			Options Outstanding						Exercisable Options
					Weighted Average
					Remaining	Weighted				Weighted
	Range of				Contractual	Average				Average
	Exercise Prices		Shares		Life (in Years)	Exercise Price			Shares	Exercise Price
	$28.01		11,426		0.3	$	28.01		11,426	$	28.01
	$33.40		4,001		0.6	$	33.4		4,001	$	33.4
	$39.62		44,543		0.1	$	39.62		44,543	$	39.62
	$41.09		99,147		3.1	$	41.09		99,147	$	41.09
	$47.30 - $51.05		11,343		1.1	$	47.85		11,343	$	47.85
	$70.13 - $70.65		47,413		1.9	$	70.26		47,413	$	70.26

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
Computation of Earnings per Share	The computation of earnings per share is as follows:
		Year Ended December 31,
	(Amounts in thousands, except per share data)	2014			2013			2012
	Net income from continuing operations applicable to Piper Jaffray Companies	$	63,172		$	49,829		$	47,075
	Net loss from discontinued operations	—			(4,739		)	(5,807		)
	Net income applicable to Piper Jaffray Companies	63,172			45,090			41,268
	Earnings allocated to participating securities (1)	(5,031		)	(4,494		)	(5,933		)
	Net income applicable to Piper Jaffray Companies’ common shareholders (2)	$	58,141		$	40,596		$	35,335
	Shares for basic and diluted calculations:
	Average shares used in basic computation	14,971			15,046			15,615
	Stock options	54			15			1
	Average shares used in diluted computation	15,025			15,061			15,616
	Earnings/(loss) per basic common share:
	Income from continuing operations	$	3.88		$	2.98		$	2.58
	Loss from discontinued operations	—			(0.28		)	(0.32		)
	Earnings per basic common share	$	3.88		$	2.7		$	2.26
	Earnings/(loss) per diluted common share:
	Income from continuing operations	$	3.87		$	2.98		$	2.58
	Loss from discontinued operations	—			(0.28		)	(0.32		)
	Earnings per diluted common share	$	3.87		$	2.7		$	2.26
	-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 1,299,827; 1,667,067 and 2,622,438 for the years ended December 31, 2014, 2013 and 2012, 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)	12 Months Ended
	Dec. 31, 2014
Segment Reporting [Abstract]
Reportable Segment Financial Results	Reportable segment financial results from continuing operations are as follows:
		Year Ended December 31,
	(Dollars in thousands)	2014			2013			2012
	Capital Markets
	Investment banking
	Financing
	Equities	$	116,684		$	100,224		$	73,180
	Debt	67,731			74,284			74,102
	Advisory services	186,176			74,420			86,165
	Total investment banking	370,591			248,928			233,447
	Institutional sales and trading
	Equities	82,211			91,169			75,723
	Fixed income	92,200			76,275			111,492
	Total institutional sales and trading	174,411			167,444			187,215
	Management and performance fees	5,398			3,891			1,678
	Investment income	24,046			30,404			9,840
	Long-term financing expenses	(6,655		)	(7,420		)	(7,982		)
	Net revenues	567,791			443,247			424,198
	Operating expenses (1)	478,661			393,231			371,628
	Segment pre-tax operating income	$	89,130		$	50,016		$	52,570
	Segment pre-tax operating margin	15.7		%	11.3		%	12.4		%
		Year Ended December 31,
	(Dollars in thousands)	2014			2013			2012
	Asset Management
	Management and performance fees
	Management fees	$	78,772		$	71,314		$	63,236
	Performance fees	892			7,840			785
	Total management and performance fees	79,664			79,154			64,021
	Investment income	683			2,794			733
	Net revenues	80,347			81,948			64,754
	Operating expenses (1)	59,166			56,351			48,313
	Segment pre-tax operating income	$	21,181		$	25,597		$	16,441
	Segment pre-tax operating margin	26.4		%	31.2		%	25.4		%
	Total
	Net revenues	$	648,138		$	525,195		$	488,952
	Operating expenses (1)	537,827			449,582			419,941
	Pre-tax operating income	$	110,311		$	75,613		$	69,011
	Pre-tax operating margin	17		%	14.4		%	14.1		%
	-1	Operating expenses include intangible asset amortization expense as set forth in the table below:
		Year Ended December 31,
	(Dollars in thousands)	2014			2013			2012
	Capital Markets	$	2,972		$	1,349		$	—
	Asset Management	6,300			6,644			6,944
	Total intangible asset amortization expense	$	9,272		$	7,993		$	6,944
Schedule of Intangible Asset Amortization Expense	Operating expenses include intangible asset amortization expense as set forth in the table below:
		Year Ended December 31,
	(Dollars in thousands)	2014			2013			2012
	Capital Markets	$	2,972		$	1,349		$	—
	Asset Management	6,300			6,644			6,944
	Total intangible asset amortization expense	$	9,272		$	7,993		$	6,944
Net Revenues by Geographic Locations
		Year Ended December 31,
	(Dollars in thousands)	2014			2013			2012
	Net revenues:
	United States	$	632,625		$	513,433		$	476,718
	Europe	15,513			11,762			12,234
	Consolidated	$	648,138		$	525,195		$	488,952
Long-Lived Assets by Geographic Region	The following table presents long-lived assets by geographic region:
		December 31,			December 31,
	(Dollars in thousands)	2014			2013
	Long-lived assets:
	United States	$	300,421		$	296,516
	Europe	5,516			6,414
	Consolidated	$	305,937		$	302,930

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Schedule of Components of Income Tax Expense	The components of income tax expense from continuing operations are as follows:
		Year Ended December 31,
	(Dollars in thousands)	2014			2013			2012
	Current:
	Federal	$	37,331		$	20,468		$	16,939
	State	8,117			3,795			(9,563		)
	Foreign	161			183			—
		45,609			24,446			7,376
	Deferred:
	Federal	(8,641		)	(1,582		)	7,735
	State	(1,317		)	(4,041		)	4,413
	Foreign	335			1,567			(54		)
		(9,623		)	(4,056		)	12,094
	Total income tax expense from continuing operations	$	35,986		$	20,390		$	19,470
	Total income tax benefit from discontinued operations	$	—		$	(2,935	)	$	(23,795	)
Schedule of Effective Income Tax Rate Reconciliation	A reconciliation of federal income taxes at statutory rates to the Company’s effective tax rates from continuing operations is as follows:
		Year Ended December 31,
	(Dollars in thousands)	2014			2013			2012
	Federal income tax expense at statutory rates	$	38,609		$	26,464		$	24,153
	Increase/(reduction) in taxes resulting from:
	State income taxes, net of federal tax benefit	3,857			2,785			2,540
	Net tax-exempt interest income	(3,693		)	(3,917		)	(3,353		)
	Foreign jurisdictions tax rate differential	(63		)	(185		)	(164		)
	Change in valuation allowance	—			(4,182		)	(1,110		)
	Restricted stock deferred tax asset write-off	—			—			4,577
	Income attributable to noncontrolling interests	(3,903		)	(1,888		)	(863		)
	Other, net	1,179			1,313			(6,310		)
	Total income tax expense from continuing operations	$	35,986		$	20,390		$	19,470
Schedule of Net Deferred Tax Assets and Liabilities	Deferred income tax assets and liabilities reflect the tax effect of temporary differences between the carrying amount of assets and liabilities for financial reporting purposes and the amounts used for the same items for income tax reporting purposes. The net deferred income tax assets included in other assets on the consolidated statements of financial condition consisted of the following items:
		December 31,			December 31,
	(Dollars in thousands)	2014			2013
	Deferred tax assets:
	Deferred compensation	$	56,893		$	43,608
	Net operating loss carry forwards	4,854			5,569
	Liabilities/accruals not currently deductible	1,601			1,903
	Other	2,930			1,459
	Total deferred tax assets	66,278			52,539
	Valuation allowance	(159		)	(159		)
	Deferred tax assets after valuation allowance	66,119			52,380
	Deferred tax liabilities:
	Goodwill amortization	15,028			9,957
	Unrealized gains on firm investments	3,221			3,577
	Fixed assets	945			1,017
	Other	1,074			1,577
	Total deferred tax liabilities	20,268			16,128
	Net deferred tax assets	$	45,851		$	36,252
Changes in Amount of Unrecognized Tax Benefits	A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows:
	(Dollars in thousands)
	Balance at December 31, 2011	$	8,915
	Additions based on tax positions related to the current year	—
	Additions for tax positions of prior years	200
	Reductions for tax positions of prior years	(8,825		)
	Settlements	—
	Balance at December 31, 2012	$	290
	Additions based on tax positions related to the current year	—
	Additions for tax positions of prior years	2,000
	Reductions for tax positions of prior years	(90		)
	Settlements	—
	Balance at December 31, 2013	$	2,200
	Additions based on tax positions related to the current year	—
	Additions for tax positions of prior years	123
	Reductions for tax positions of prior years	—
	Settlements	—
	Balance at December 31, 2014	$	2,323

Pipar_Jaffray_Companies_Parent

Pipar Jaffray Companies (Parent Company only) (Tables) (Parent Company [Member])	12 Months Ended
	Dec. 31, 2014
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Condensed Statement of Financial Condition	Condensed Statements of Financial Condition
		December 31,			December 31,
	(Amounts in thousands)	2014			2013
	Assets
	Cash and cash equivalents	$	200		$	336
	Investment in and advances to subsidiaries	956,609			870,104
	Other assets	13,819			9,119
	Total assets	$	970,628		$	879,559
	Liabilities and Shareholders’ Equity
	Variable rate senior notes	$	125,000		$	125,000
	Accrued compensation	24,618			18,454
	Other liabilities and accrued expenses	1,098			1,429
	Total liabilities	150,716			144,883
	Shareholders’ equity	819,912			734,676
	Total liabilities and shareholders’ equity	$	970,628		$	879,559
Condensed Statement of Operations	Condensed Statements of Operations
		Year Ended December 31,
	(Amounts in thousands)	2014			2013			2012
	Revenues:
	Dividends from subsidiaries	$	50,333		$	46,000		$	119,000
	Interest	662			254			82
	Other revenues	275			198			—
	Total revenues	51,270			46,452			119,082
	Interest expense	5,463			5,850			5,823
	Net revenues	45,807			40,602			113,259
	Non-interest expenses:
	Total non-interest expenses	5,318			3,096			4,222
	Income from continuing operations before income tax expense and equity in undistributed/(distributed in excess of) income of subsidiaries	40,489			37,506			109,037
	Income tax expense	14,795			13,263			39,175
	Income from continuing operations of parent company	25,694			24,243			69,862
	Equity in undistributed/(distributed in excess of) income of subsidiaries	37,478			25,200			(49,617		)
	Net income from continuing operations	63,172			49,443			20,245
	Discontinued operations:
	Income/(loss) from discontinued operations, net of tax	—			(4,353		)	21,023
	Net income	$	63,172		$	45,090		$	41,268
Condensed Statement of Cash Flows	Condensed Statements of Cash Flows
		Year Ended December 31,
	(Amounts in thousands)	2014			2013			2012
	Operating Activities:
	Net income	$	63,172		$	45,090		$	41,268
	Adjustments to reconcile net income to net cash provided by operating activities:
	Share-based and deferred compensation	180			60			240
	Equity distributed in excess of/(in undistributed) income of subsidiaries	(37,478		)	(25,200		)	49,617
	Net cash provided by operating activities	25,874			19,950			91,125
	Investing Activities:
	Repayment of FAMCO note	2,000			250			—
	Net cash provided by investing activities	2,000			250			—
	Financing Activities:
	Issuance of variable rate senior notes	50,000			—			125,000
	Repayment of variable rate senior notes	(50,000		)	—			—
	Decrease in bank syndicated financing	—			—			(115,000		)
	Advances from/(to) subsidiaries	(28,010		)	34,996			(76,481		)
	Repurchase of common stock	—			(55,929		)	(38,068		)
	Net cash used in financing activities	(28,010		)	(20,933		)	(104,549		)
	Net decrease in cash and cash equivalents	(136		)	(733		)	(13,424		)
	Cash and cash equivalents at beginning of year	336			1,069			14,493
	Cash and cash equivalents at end of year	$	200		$	336		$	1,069
	Supplemental disclosures of cash flow information
	Cash paid during the year for:
	Interest	$	(4,801	)	$	(5,596	)	$	(5,741	)
	Income taxes	$	(14,795	)	$	(13,263	)	$	(39,175	)

Quarterly_Information_unaudite1

Quarterly Information (unaudited) (Tables)	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Quarterly Information	Quarterly Information (unaudited)
		2014 Fiscal Quarter
	(Amounts in thousands, except per share data)		First			Second			Third			Fourth
	Total revenues		$	173,894		$	175,976		$	165,947		$	157,394
	Interest expense		5,761			5,945			6,521			6,846
	Net revenues		168,133			170,031			159,426			150,548
	Non-interest expenses		135,420			139,614			133,734			129,059
	Income from continuing operations before income tax expense		32,713			30,417			25,692			21,489
	Income tax expense		9,827			10,049			8,596			7,514
	Net income from continuing operations		22,886			20,368			17,096			13,975
	Loss from discontinued operations, net of tax		—			—			—			—
	Net income		22,886			20,368			17,096			13,975
	Net income applicable to noncontrolling interests		5,138			2,155			2,428			1,432
	Net income applicable to Piper Jaffray Companies		$	17,748		$	18,213		$	14,668		12,543
	Net income applicable to Piper Jaffray Companies' common shareholders		$	16,089		$	16,717		$	13,552		$	11,700
	Amounts applicable to Piper Jaffray Companies
	Net income from continuing operations		$	17,748		$	18,213		$	14,668		$	12,543
	Net loss from discontinued operations		—			—			—			—
	Net income applicable to Piper Jaffray Companies		$	17,748		$	18,213		$	14,668		$	12,543
	Earnings per basic common share
	Income from continuing operations		$	1.1		$	1.12		$	0.9		$	0.77
	Loss from discontinued operations		—			—			—			—
	Earnings per basic common share		$	1.1		$	1.12		$	0.9		$	0.77
	Earnings per diluted common share
	Income from continuing operations		$	1.1		$	1.11		$	0.9		$	0.77
	Loss from discontinued operations		—			—			—			—
	Earnings per diluted common share		$	1.1		$	1.11		$	0.9		$	0.77
	Weighted average number of common shares
	Basic		14,612			14,958			15,066			15,241
	Diluted		14,657			15,013			15,129			15,293
		2013 Fiscal Quarter
	(Amounts in thousands, except per share data)		First			Second			Third			Fourth
	Total revenues		$	115,312		$	106,520		$	134,506		$	193,893
	Interest expense		5,779			6,748			6,192			6,317
	Net revenues		109,533			99,772			128,314			187,576
	Non-interest expenses		91,365			96,439			116,254			145,524
	Income from continuing operations before income tax expense		18,168			3,333			12,060			42,052
	Income tax expense		5,600			1,644			2,886			10,260
	Net income from continuing operations		12,568			1,689			9,174			31,792
	Loss from discontinued operations, net of tax		(521		)	(1,871		)	(1,529		)	(818		)
	Net income/(loss)		12,047			(182		)	7,645			30,974
	Net income/(loss) applicable to noncontrolling interests		1,901			(2,670		)	2,323			3,840
	Net income applicable to Piper Jaffray Companies		$	10,146		$	2,488		$	5,322		$	27,134
	Net income applicable to Piper Jaffray Companies' common shareholders		$	8,966		$	2,266		$	4,826		$	24,445
	Amounts applicable to Piper Jaffray Companies
	Net income from continuing operations		$	10,667		$	4,359		$	6,851		$	27,952
	Loss from discontinued operations		(521		)	(1,871		)	(1,529		)	(818		)
	Net income applicable to Piper Jaffray Companies		$	10,146		$	2,488		$	5,322		$	27,134
	Earnings per basic common share
	Income from continuing operations		$	0.6		$	0.25		$	0.42		$	1.75
	Loss from discontinued operations		(0.03		)	(0.11		)	(0.09		)	(0.05		)
	Earnings per basic common share		$	0.58		$	0.15		$	0.33		$	1.7
	Earnings per diluted common share
	Income from continuing operations		$	0.6		$	0.25		$	0.42		$	1.75
	Loss from discontinued operations		(0.03		)	(0.11		)	(0.09		)	(0.05		)
	Earnings per diluted common share		$	0.57		$	0.15		$	0.33		$	1.7
	Weighted average number of common shares
	Basic		15,582			15,621			14,641			14,378
	Diluted		15,610			15,626			14,626			14,397

Organization_and_Basis_of_Pres1

Organization and Basis of Presentation - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2012
	segment
Condensed Financial Statements, Captions [Line Items]
Number of reportable segments	2
Interest Revenue [Member]
Condensed Financial Statements, Captions [Line Items]
Reclassified amount		$11
Interest Expense [Member]
Condensed Financial Statements, Captions [Line Items]
Reclassified amount		$10.20

Summary_of_Significant_Account2

Summary of Significant Accounting Policies - Additional Disclosures (Details)	12 Months Ended
	Dec. 31, 2014
Minimum
Property, Plant and Equipment [Line Items]
Finite-lived intangible asset, useful life	2 years
Employee loans term	2 years
Maximum
Property, Plant and Equipment [Line Items]
Lease term	12 years
Finite-lived intangible asset, useful life	10 years
Employee loans term	5 years
Furniture and equipment | Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	3 years
Furniture and equipment | Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	10 years
Internal use software | Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	3 years
Internal use software | Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	7 years

Acquisitions_Additional_Inform

Acquisitions - Additional Information(Details) (USD $)	12 Months Ended		0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Jul. 16, 2013
Business Acquisition [Line Items]
Goodwill acquired	$0	$13,790,000
Seattle-Northwest Securities Corporation and Edgeview Partners, L.P.
Business Acquisition [Line Items]
Consideration transferred			32,700,000
Acquisition related compensation arrangements			14,300,000
Goodwill acquired			15,000,000
Goodwill amount expected to be deducted for income tax purposes			9,100,000
Intangible assets	6,665,000		6,665,000
Acquisition related costs		1,100,000
Seattle-Northwest Securities Corporation and Edgeview Partners, L.P. | Customer Relationships
Business Acquisition [Line Items]
Intangible assets			6,000,000
Seattle-Northwest Securities Corporation and Edgeview Partners, L.P. | Noncompete Agreements
Business Acquisition [Line Items]
Intangible assets			$700,000
Seattle-Northwest Securities Corporation and Edgeview Partners, L.P. | Minimum
Business Acquisition [Line Items]
Acquisition related compensation arrangement award vesting period			2 years
Seattle-Northwest Securities Corporation and Edgeview Partners, L.P. | Maximum
Business Acquisition [Line Items]
Acquisition related compensation arrangement award vesting period			5 years
Seattle-Northwest Securities Corporation and Edgeview Partners, L.P. | Weighted Average
Business Acquisition [Line Items]
Acquisition related compensation arrangement award vesting period			2 years 11 months

Acquisitions_Estimated_Fair_Va

Acquisitions - Estimated Fair Values of Assets Acquired and Liabilities Assumed (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jul. 16, 2013
In Thousands, unless otherwise specified
Assets
Goodwill	$211,878	$210,634	$196,844
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				15,034
Intangible assets	6,665			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 $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2013
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Net revenues	$535,694
Net income from continuing operations applicable to Piper Jaffray Companies	50,413
Seattle-Northwest Securities Corporation and Edgeview Partners, L.P. [Member]
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Net revenues		541,304
Net income from continuing operations applicable to Piper Jaffray Companies		$48,568

Discontinued_Operations_Detail

Discontinued Operations (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Goodwill impairment									$0
Income tax benefit									0	-2,935	-23,795
Loss on sale, net of tax									0	-1,876	0
Loss from discontinued operations, net of tax	0	0	0	0	-818	-1,529	-1,871	-521	0	-4,739	-5,807
Hong Kong Capital Markets
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net revenues										0	6,635
Restructure expenses										0	11,535
Other expenses										1,197	16,550
Total non-interest expenses										1,197	28,085
Loss from discontinued operations before income tax benefit										-1,197	-21,450
Income tax benefit										-415	-21,069
Loss from discontinued operations, net of tax										-782	-381
FAMCO
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net revenues										1,650	5,718
Goodwill impairment										0	5,508
Operating expenses										5,057	8,362
Total non-interest expenses										5,057	13,870
Loss from discontinued operations before income tax benefit										-3,407	-8,152
Income tax benefit										-1,326	-2,726
Loss from discontinued operations										-2,081	-5,426
Loss on sale, net of tax										-1,876	0
Loss from discontinued operations, net of tax										($3,957)	($5,426)

Discontinued_Operations_Detail1

Discontinued Operations (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on sale of FAMCO	$0	($1,876,000)	$0
Sale of FAMCO, cash proceeds	2,000,000	250,000	0
FAMCO
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on sale of FAMCO		-1,876,000	0
Sale of FAMCO, sale price		4,000,000
Sale of FAMCO, cash proceeds		250,000
Sale of FAMCO, note receivable received		$3,700,000

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 $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Financial instruments and other inventory positions owned	$1,616,361	$1,364,028
Financial instruments and other inventory positions sold, but not yet purchased	738,124	512,833
Financial instruments and other inventory positions owned and pledged as collateral	1,108,567	957,515
Equity securities
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Financial instruments and other inventory positions owned	50,365	54,097
Financial instruments and other inventory positions sold, but not yet purchased	154,589	69,205
Convertible securities
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Financial instruments and other inventory positions owned	156,685	80,784
Fixed income securities
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Financial instruments and other inventory positions owned	48,651	10,102
Financial instruments and other inventory positions sold, but not yet purchased	21,460	24,021
Taxable securities
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Financial instruments and other inventory positions owned	312,753	232,379
Tax-exempt securities
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Financial instruments and other inventory positions owned	559,704	460,865
Short-term securities
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Financial instruments and other inventory positions owned	68,717	62,620
Asset-backed securities
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Financial instruments and other inventory positions owned	125,065	119,811
U.S. government agency securities
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Financial instruments and other inventory positions owned	244,046	304,737
Financial instruments and other inventory positions sold, but not yet purchased	27,735	120,084
U.S. government securities
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Financial instruments and other inventory positions owned	2,549	0
Financial instruments and other inventory positions sold, but not yet purchased	523,527	291,320
Derivative contracts
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Financial instruments and other inventory positions owned	47,826	38,633
Financial instruments and other inventory positions sold, but not yet purchased	10,813	8,203
Municipal Bond Fund
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Financial instruments and other inventory positions owned	267,742	291,513
Financial instruments and other inventory positions sold, but not yet purchased	98,669	68,356
Municipal Bond Fund | Taxable securities
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Financial instruments and other inventory positions owned	123,300	101,800
Municipal Bond Fund | Tax-exempt securities
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Financial instruments and other inventory positions owned	139,500	183,900
Municipal Bond Fund | U.S. government securities
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Financial instruments and other inventory positions sold, but not yet purchased	97,600	67,400
Municipal Bond Fund | Derivative contracts
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Financial instruments and other inventory positions owned	4,900	5,800
Financial instruments and other inventory positions sold, but not yet purchased	1,100	1,000
Parent Company [Member]
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]
Financial instruments and other inventory positions owned	1,348,619	1,072,515
Financial instruments and other inventory positions sold, but not yet purchased	$639,455	$444,477

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 $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Derivative [Line Items]
Absolute Notional Contract Amount of Derivative Instruments	$5,444,728	$5,825,852
Customer matched-book | Interest rate derivative contract
Derivative [Line Items]
Absolute Notional Contract Amount of Derivative Instruments	4,860,302	5,310,929
Trading securities | Interest rate derivative contract
Derivative [Line Items]
Absolute Notional Contract Amount of Derivative Instruments	297,250	198,500
Trading securities | Credit default swap index contract
Derivative [Line Items]
Absolute Notional Contract Amount of Derivative Instruments	267,796	299,333
Trading securities | Equity option derivative contract
Derivative [Line Items]
Absolute Notional Contract Amount of Derivative Instruments	$19,380	$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) (Not Designated as Hedging Instrument [Member], USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized Gain (Loss) on Derivatives Instruments	($4,511)	($6,208)	($4,984)
Interest rate derivative contract | Investment banking
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized Gain (Loss) on Derivatives Instruments	-2,790	-1,529	-2,583
Interest rate derivative contract | Institutional brokerage
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized Gain (Loss) on Derivatives Instruments	-1,678	-2,511	-798
Credit default swap index contract | Institutional brokerage
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized Gain (Loss) on Derivatives Instruments	-1,080	-1,522	-1,603
Equity option derivative contract | Institutional brokerage
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized Gain (Loss) on Derivatives Instruments	$1,037	($646)	$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) (Not Designated as Hedging Instrument [Member], USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Derivatives, Fair Value [Line Items]
Fair value of derivative assets, gross	$454,011
Fair value of derivative liabilities, gross	438,846
Interest rate derivative contract | Financial instruments and other inventory positions owned
Derivatives, Fair Value [Line Items]
Fair value of derivative assets, gross	448,127
Interest rate derivative contract | Financial instruments and other inventory positions sold, but not yet purchased
Derivatives, Fair Value [Line Items]
Fair value of derivative liabilities, gross	433,469
Credit default swap index contract | Financial instruments and other inventory positions owned
Derivatives, Fair Value [Line Items]
Fair value of derivative assets, gross	5,808
Credit default swap index contract | Financial instruments and other inventory positions sold, but not yet purchased
Derivatives, Fair Value [Line Items]
Fair value of derivative liabilities, gross	5,188
Equity option derivative contract | Financial instruments and other inventory positions owned
Derivatives, Fair Value [Line Items]
Fair value of derivative assets, gross	76
Equity option derivative contract | Financial instruments and other inventory positions sold, but not yet purchased
Derivatives, Fair Value [Line Items]
Fair value of derivative liabilities, gross	$189

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) (Maximum risk of loss, USD $)	Dec. 31, 2014
In Millions, unless otherwise specified
Counterparties not required to post collateral [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Uncollateralized credit exposure	$28.30
Notional contract amount	197.8
One unnamed financial institutional not required to post collateral [Member]
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Uncollateralized credit exposure	$16.50

Fair_Value_of_Financial_Instru2

Fair Value of Financial Instruments Fair Value Option (Details) (Level III, USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments at fair value	$74,165,000	$49,240,000
Merchant Banking Investments
Fair Value, Option, Quantitative Disclosures [Line Items]
Investments at fair value	18,400,000	16,100,000
Gains from changes in fair value	$2,700,000	$10,600,000	$2,600,000

Fair_Value_of_Financial_Instru3

Fair Value of Financial Instruments - Information about Significant Unobservable Inputs used in Fair Value Measurement (Details) (Level III)	12 Months Ended
	Dec. 31, 2014
Financial instruments and other inventory positions sold, but not yet purchased | Minimum | Discounted cash flow | Interest rate locks
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]
Unamortized premium over the MMD curve	0.01%
Financial instruments and other inventory positions sold, but not yet purchased | Maximum | Discounted cash flow | Interest rate locks
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]
Unamortized premium over the MMD curve	0.28%
Financial instruments and other inventory positions sold, but not yet purchased | Weighted Average | Discounted cash flow | Interest rate locks
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 | Minimum | Discounted cash flow | 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 | Short-term securities
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]
Expected recovery rate (% of par)	66.00%
Financial instruments and other inventory positions owned | Minimum | Discounted cash flow | Collateralized by Residential mortgages
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]
Credit default rate	1.00%
Prepayment rates	2.00%
Loss severity	31.00%
Valuation yields	5.00%
Financial instruments and other inventory positions owned | Minimum | Discounted cash flow | Interest rate locks
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]
Unamortized premium over the MMD curve	0.00%
Financial instruments and other inventory positions owned | Minimum | Black-Scholes option pricing model | 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 | Warrants in private companies
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]
Stock volatility factors of comparable companies	21.00%
Financial instruments and other inventory positions owned | Minimum | Market approach | Equity investment in private company
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]
Revenue multiple	2
EBITDA multiple	9
Financial instruments and other inventory positions owned | Maximum | Discounted cash flow | Tax-exempt securities
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]
Debt service coverage ratio	60.00%
Financial instruments and other inventory positions owned | Maximum | Discounted cash flow | Short-term securities
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]
Expected recovery rate (% of par)	94.00%
Financial instruments and other inventory positions owned | Maximum | Discounted cash flow | Collateralized by Residential mortgages
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]
Credit default rate	8.00%
Prepayment rates	21.00%
Loss severity	95.00%
Valuation yields	6.00%
Financial instruments and other inventory positions owned | Maximum | Discounted cash flow | Interest rate locks
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 | Maximum | Black-Scholes option pricing model | 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 | Warrants in private companies
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]
Stock volatility factors of comparable companies	54.00%
Financial instruments and other inventory positions owned | Maximum | Market approach | Equity investment in private company
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]
Revenue multiple	6
EBITDA multiple	12
Financial instruments and other inventory positions owned | Weighted Average | Discounted cash flow | Tax-exempt securities
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]
Debt service coverage ratio	19.40%
Financial instruments and other inventory positions owned | Weighted Average | Discounted cash flow | Short-term securities
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]
Expected recovery rate (% of par)	91.00%
Financial instruments and other inventory positions owned | Weighted Average | Discounted cash flow | Collateralized by Residential mortgages
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]
Credit default rate	4.20%
Prepayment rates	4.12%
Loss severity	70.86%
Valuation yields	5.29%
Financial instruments and other inventory positions owned | Weighted Average | Discounted cash flow | Interest rate locks
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]
Unamortized premium over the MMD curve	0.13%
Financial instruments and other inventory positions owned | Weighted Average | Black-Scholes option pricing model | Warrants in public and private companies
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]
Liquidity discount rates	30.70%
Financial instruments and other inventory positions owned | Weighted Average | Black-Scholes option pricing model | Warrants in private companies
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]
Stock volatility factors of comparable companies	28.00%
Financial instruments and other inventory positions owned | Weighted Average | Market approach | Equity investment in private company
Fair Value Inputs Assets and Liabilities Quantitative Information [Line Items]
Revenue multiple	4
EBITDA multiple	9.5

Fair_Value_of_Financial_Instru4

Fair Value of Financial Instruments - Additional Information (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Transfers into Level III	$3,552
Level II
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	1,853,935	1,515,285
Level III
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	$200,960	$171,919
Percentage of Level III assets to financial instruments measured at fair value	11.70%	11.20%
U.S. government agency securities | Minimum | Level II
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Market yields basis points spreads to treasury securities (as a percent)	0.49%
Prepayment expectations based upon PSA prepayment levels	37
U.S. government agency securities | Maximum | Level II
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Market yields basis points spreads to treasury securities (as a percent)	9.47%
Prepayment expectations based upon PSA prepayment levels	460

Fair_Value_of_Financial_Instru5

Fair Value of Financial Instruments - Valuation of Financial Instruments by Pricing Observability Levels (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	$1,616,361	$1,364,028
Derivative contracts	-406,185	-313,666
Financial instruments and other inventory positions sold, but not yet purchased	738,124	512,833
Derivative contracts	-428,033	-324,394
Equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	50,365	54,097
Financial instruments and other inventory positions sold, but not yet purchased	154,589	69,205
Convertible securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	156,685	80,784
Fixed income securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	48,651	10,102
Financial instruments and other inventory positions sold, but not yet purchased	21,460	24,021
Taxable securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	312,753	232,379
Tax-exempt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	559,704	460,865
Short-term securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	68,717	62,620
Asset-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	125,065	119,811
U.S. government agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	244,046	304,737
Financial instruments and other inventory positions sold, but not yet purchased	27,735	120,084
U.S. government securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	2,549	0
Financial instruments and other inventory positions sold, but not yet purchased	523,527	291,320
Derivative contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	47,826	38,633
Derivative contracts	-406,185	-313,666
Financial instruments and other inventory positions sold, but not yet purchased	10,813	8,203
Derivative contracts	-428,033	-324,394
Level I
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	41,816	39,730
Cash equivalents	1,562	101,629
Investments at fair value	20,704	20,690
Total assets	64,082	162,049
Financial instruments and other inventory positions sold, but not yet purchased	676,970	362,414
Level I | Equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	39,191	39,711
Financial instruments and other inventory positions sold, but not yet purchased	153,254	69,205
Level I | U.S. government securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	2,549
Financial instruments and other inventory positions sold, but not yet purchased	523,527	291,320
Level I | Derivative contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	76	19
Financial instruments and other inventory positions sold, but not yet purchased	189	1,889
Level II
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	1,853,935	1,515,285
Total assets	1,853,935	1,515,285
Financial instruments and other inventory positions sold, but not yet purchased	481,365	468,170
Level II | Equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	11,174	14,386
Financial instruments and other inventory positions sold, but not yet purchased	1,335
Level II | Convertible securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	156,685	80,784
Level II | Fixed income securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	48,651	10,002
Financial instruments and other inventory positions sold, but not yet purchased	21,460	24,021
Level II | Taxable securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	312,753	232,379
Level II | Tax-exempt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	558,518	459,432
Level II | Short-term securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	67,997	61,964
Level II | Asset-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	316	12
Level II | U.S. government agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	244,046	304,737
Financial instruments and other inventory positions sold, but not yet purchased	27,735	120,084
Level II | Derivative contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	453,795	351,589
Financial instruments and other inventory positions sold, but not yet purchased	430,835	324,065
Level III
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	126,795	122,679
Investments at fair value	74,165	49,240
Total assets	200,960	171,919
Financial instruments and other inventory positions sold, but not yet purchased	7,822	6,643
Level III | Fixed income securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned		100
Level III | Tax-exempt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	1,186	1,433
Level III | Short-term securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	720	656
Level III | Asset-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	124,749	119,799
Level III | Derivative contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	140	691
Financial instruments and other inventory positions sold, but not yet purchased	7,822	6,643
Measured on a recurring basis
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	1,616,361	1,364,028
Cash equivalents	1,562	101,629
Investments at fair value	94,869	69,930
Total assets	1,712,792	1,535,587
Financial instruments and other inventory positions sold, but not yet purchased	738,124	512,833
Measured on a recurring basis | Equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	50,365	54,097
Financial instruments and other inventory positions sold, but not yet purchased	154,589	69,205
Measured on a recurring basis | Convertible securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	156,685	80,784
Measured on a recurring basis | Fixed income securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	48,651	10,102
Financial instruments and other inventory positions sold, but not yet purchased	21,460	24,021
Measured on a recurring basis | Taxable securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	312,753	232,379
Measured on a recurring basis | Tax-exempt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	559,704	460,865
Measured on a recurring basis | Short-term securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	68,717	62,620
Measured on a recurring basis | Asset-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	125,065	119,811
Measured on a recurring basis | U.S. government agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	244,046	304,737
Financial instruments and other inventory positions sold, but not yet purchased	27,735	120,084
Measured on a recurring basis | U.S. government securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	2,549
Financial instruments and other inventory positions sold, but not yet purchased	523,527	291,320
Measured on a recurring basis | Derivative contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial instruments and other inventory positions owned	47,826	38,633
Financial instruments and other inventory positions sold, but not yet purchased	$10,813	$8,203

Fair_Value_of_Financial_Instru6

Fair Value of Financial Instruments - Changes in Fair Value Associated with Level III Financial Instruments (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$171,919	$152,328
Purchases	179,670	244,565
Sales	-164,455	-251,600
Transfers into Level III	3,552
Transfers out		-619
Realized gains/ (losses)	7,961	25,431
Unrealized gains/ (losses)	2,313	1,814
Ending balance	200,960	171,919
Unrealized gains/(losses) for assets held at period end	4,916	6,440
Unrealized gains/(losses) for liabilities held at period end	7,822	6,643
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	6,643	5,218
Purchases	-16,751	-5,702
Sales		457
Realized gains/(losses)	16,751	5,232
Unrealized gains/ (losses)	1,179	1,438
Ending balance	7,822	6,643
Financial instruments and other inventory positions sold, but not yet purchased | Derivative contracts
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Unrealized gains/(losses) for liabilities held at period end	7,822	6,643
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	6,643	5,218
Issuances	-16,751	-5,702
Settlements		-457
Realized gains/(losses)	16,751	5,232
Unrealized gains/ (losses)	1,179	1,438
Ending balance	7,822	6,643
Financial instruments and other inventory positions owned
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	122,679	119,083
Purchases	157,940	227,740
Sales	-162,087	-241,242
Transfers into Level III	3,552
Realized gains/ (losses)	5,593	19,482
Unrealized gains/ (losses)	-882	-2,384
Ending balance	126,795	122,679
Unrealized gains/(losses) for assets held at period end	1,721	2,242
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
Purchases	0	100
Sales	-100
Transfers into Level III	0
Transfers out	0
Realized gains/ (losses)	0
Unrealized gains/ (losses)	0
Ending balance	0	100
Unrealized gains/(losses) for assets held at period end	0	0
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	1,429
Purchases		1
Unrealized gains/ (losses)	-247	3
Ending balance	1,186	1,433
Unrealized gains/(losses) for assets held at period end	-247	3
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		656
Sales	-25
Realized gains/ (losses)	6
Unrealized gains/ (losses)	83
Ending balance	720		656
Unrealized gains/(losses) for assets held at period end	83
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	119,799	116,171
Purchases	154,338	227,634
Sales	-161,962	-238,860
Transfers into Level III	3,552
Realized gains/ (losses)	9,189	17,105
Unrealized gains/ (losses)	-167	-2,251
Ending balance	124,749	119,799
Unrealized gains/(losses) for assets held at period end	1,745	1,548
Financial instruments and other inventory positions owned | Derivative contracts
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	691	827
Issuances	3,602	5
Settlements		2,382
Realized gains/ (losses)	-3,602	2,377
Unrealized gains/ (losses)	-551	-136
Ending balance	140	691
Unrealized gains/(losses) for assets held at period end	140	691
Investments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	49,240	33,245
Purchases	21,730	16,825
Sales	-2,368	-10,358
Transfers out		-619
Realized gains/ (losses)	2,368	5,949
Unrealized gains/ (losses)	3,195	4,198
Ending balance	74,165	49,240
Unrealized gains/(losses) for assets held at period end	$3,195	$4,198

Fair_Value_of_Financial_Instru7

Fair Value of Financial Instruments Non-Recurring Fair Value Measurement (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Goodwill, Impairment Loss	$0
Fiduciary Asset Management, LLC [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Goodwill, Impairment Loss		0	5,508
Non-recurring fair value measurement | Fiduciary Asset Management, LLC [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Goodwill, Impairment Loss			$5,508

Variable_Interest_Entities_Add

Variable Interest Entities - Additional Information (Details) (Variable Interest Entity, Not Primary Beneficiary, Aggregated Disclosure [Member], USD $)	Dec. 31, 2014	Dec. 31, 2013
Variable Interest Entity, Not Primary Beneficiary, Aggregated Disclosure [Member]
Variable Interest Entity [Line Items]
Variable interest entity, nonconsolidated total assets	$600,000,000	$800,000,000
Variable interest entities, exposure to loss	9,000,000
VIE liabilities	$0	$0

Receivables_from_and_Payables_4

Receivables from and Payables to Brokers, Dealers and Clearing Organizations - Amounts Receivable from Brokers, Dealers and Clearing Organizations (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Brokers and Dealers [Abstract]
Receivable arising from unsettled securities transactions	$52,571	$59,657
Deposits paid for securities borrowed	57,572	36,278
Receivable from clearing organizations	4,933	966
Deposits with clearing organizations	33,799	20,995
Securities failed to deliver	1,753	593
Other	10,381	8,624
Brokers, dealers and clearing organizations	$161,009	$127,113

Receivables_from_and_Payables_5

Receivables from and Payables to Brokers, Dealers and Clearing Organizations - Amounts Payable to Brokers, Dealers and Clearing Organizations (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Brokers and Dealers [Abstract]
Payable arising from unsettled securities transactions	$11,048	$5,643
Payable to clearing organizations	5,185	9,462
Securities failed to receive	2,430	744
Other	6,901	11,873
Brokers, dealers and clearing organizations	$25,564	$27,722

Receivables_from_and_Payables_6

Receivables from and Payables to Customers Amounts Receivable from Customers (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Receivables From and Payables to Customers [Abstract]
Cash accounts	$6,135	$5,013
Margin accounts	3,523	6,620
Total receivables	$9,658	$11,633

Receivables_from_and_Payables_7

Receivables from and Payables to Customers Amounts Payable to Customers (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Receivables From and Payables to Customers [Abstract]
Cash accounts	$13,172	$30,499
Margin accounts	156	2,610
Total payables	$13,328	$33,109

Collateralized_Securities_Tran2

Collateralized Securities Transactions - Summary of Repurchase Liabilities, Fair Market Value of Related Collateral Pledged and Interest Rate Charged (Details) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Assets Sold under Agreements to Repurchase [Line Items]
Fair Market Value	$117,483
Repurchase Liability	102,646
Maturity up to 30 days [Member] | Asset-backed securities
Assets Sold under Agreements to Repurchase [Line Items]
Fair Market Value	25,632
Repurchase Liability	18,586
Maturity up to 30 days [Member] | Asset-backed securities | Minimum [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Interest Rate	1.66%
Maturity up to 30 days [Member] | Asset-backed securities | Maximum [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Interest Rate	2.01%
Maturity 30 to 90 Days [Member] | Asset-backed securities
Assets Sold under Agreements to Repurchase [Line Items]
Fair Market Value	12,823
Repurchase Liability	9,097
Maturity 30 to 90 Days [Member] | Asset-backed securities | Minimum [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Interest Rate	1.83%
Maturity 30 to 90 Days [Member] | Asset-backed securities | Maximum [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Interest Rate	1.96%
On demand maturities | U.S. government agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Fair Market Value	57,705
Repurchase Liability	54,293
On demand maturities | U.S. government agency securities | Minimum [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Interest Rate	0.50%
On demand maturities | U.S. government agency securities | Maximum [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Interest Rate	0.75%
On demand maturities | U.S. government securities
Assets Sold under Agreements to Repurchase [Line Items]
Fair Market Value	21,323
Interest Rate	0.35%
Repurchase Liability	$20,670

Collateralized_Securities_Tran3

Collateralized Securities Transactions - Additional Information (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Disclosure of Repurchase Agreements [Abstract]
Securities purchased under agreements to resell, securities borrowed and margin agreements on terms that permit to repledge or resell the securities to others	$369,700,000	$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	338,800,000	194,900,000
Reverse Repurchase, Offset Value	0
Securities loaned	$0

Investments_Investments_Detail

Investments Investments (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Investments, All Other Investments [Abstract]
Investments at fair value	$94,869	$69,930
Investments at cost	8,214	20,709
Investments accounted for under the equity method	23,757	21,404
Total investments	126,840	112,043
Less investments attributable to noncontrolling interests	-32,563	-21,137
Investments less portion attributable to noncontolling interest	$94,277	$90,906

Investments_Additional_Informa

Investments - Additional Information (Details) (USD $)	Dec. 31, 2014
Investment [Line Items]
Estimated fair market value of investments carried at cost	$13,700,000
Debt investment in private company [Member]
Investment [Line Items]
Valuation Allowances and Reserves, Balance	$0

Other_Assets_Details

Other Assets (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Net deferred income tax assets	$45,851	$36,252
Fee receivables	23,959	34,415
Accrued interest receivables	10,061	9,793
Forgivable loans, net	8,366	7,879
Prepaid expenses	6,067	5,237
Other	5,995	8,516
Total other assets	$100,299	$102,092

Goodwill_and_Intangible_Assets2

Goodwill and Intangible Assets - Changes in Carrying Value of Goodwill and Intangible Assets (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Goodwill
Goodwill beginning balance	$210,634	$196,844
Goodwill acquired	0	13,790
Measurement period adjustment	1,244
Goodwill ending balance	211,878	210,634	196,844
Intangible assets
Intangible assets beginning balance	39,930	41,258
Finite-lived Intangible Assets Acquired	0	6,665
Amortization of intangible assets	-9,272	-7,993	-6,944
Intangible assets ending balance	30,658	39,930	41,258
Capital Markets
Goodwill
Goodwill beginning balance	13,790	0
Goodwill acquired	0	13,790
Measurement period adjustment	1,244
Goodwill ending balance	15,034	13,790	0
Intangible assets
Intangible assets beginning balance	5,316	0
Finite-lived Intangible Assets Acquired	0	6,665
Amortization of intangible assets	-2,972	-1,349	0
Intangible assets ending balance	2,344	5,316	0
Asset Mgmt [Member]
Goodwill
Goodwill beginning balance	196,844	196,844
Goodwill acquired		0
Measurement period adjustment	0
Goodwill ending balance	196,844	196,844	196,844
Intangible assets
Intangible assets beginning balance	34,614	41,258
Finite-lived Intangible Assets Acquired	0	0
Amortization of intangible assets	-6,300	-6,644	-6,944
Intangible assets ending balance	$28,314	$34,614	$41,258

Goodwill_and_Intangible_Assets3

Goodwill and Intangible Assets - Additional Information (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jul. 16, 2013
	segment
Goodwill And Intangible Assets Disclosure [Line Items]
Number of Reportable Segments	2
Goodwill, Impairment Loss	$0
Impairment of Intangible Assets	0
Measurement period adjustment	1,244,000
Minimum [Member]
Goodwill And Intangible Assets Disclosure [Line Items]
Finite-Lived Intangible Asset, Useful Life	2 years
Maximum [Member]
Goodwill And Intangible Assets Disclosure [Line Items]
Finite-Lived Intangible Asset, Useful Life	10 years
Seattle-Northwest Securities Corporation and Edgeview Partners, L.P. [Member]
Goodwill And Intangible Assets Disclosure [Line Items]
Measurement period adjustment	1,244,000
Acquired intangible assets	6,665,000			6,665,000
Seattle-Northwest Securities Corporation and Edgeview Partners, L.P. [Member] | Customer Relationships
Goodwill And Intangible Assets Disclosure [Line Items]
Acquired intangible assets				6,000,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	1 year 11 months
Seattle-Northwest Securities Corporation and Edgeview Partners, L.P. [Member] | Noncompete Agreements
Goodwill And Intangible Assets Disclosure [Line Items]
Acquired intangible assets				700,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	3 years
FAMCO
Goodwill And Intangible Assets Disclosure [Line Items]
Goodwill, Impairment Loss		$0	($5,508,000)

Goodwill_and_Intangible_Assets4

Goodwill and Intangible Assets - Aggregate Future Intangible Asset Amortization Expense (Details) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2015	$7,093
2016	6,219
2017	5,230
2018	4,804
2019	4,452
Total	$27,798

Fixed_Assets_Summary_of_Fixed_

Fixed Assets - Summary of Fixed Assets (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$65,498	$78,425
Accumulated depreciation and amortization	-47,327	-62,311
Property, Plant and Equipment, Net	18,171	16,114
Furniture and equipment
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	28,669	34,980
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	23,697	23,478
Software
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$13,132	$19,967

Fixed_Assets_Additional_Inform

Fixed Assets - Additional Information (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Abstract]
Depreciation and amortization	$5.30	$5.60	$6.50

ShortTerm_Financing_Summary_of

Short-Term Financing - Summary of Short Term Financing and Weighted Average Interest Rate on Borrowings (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Short-term Debt [Line Items]
Oustanding Balance	$377,767,000	$514,711,000
Commercial paper (secured)
Short-term Debt [Line Items]
Oustanding Balance	238,013,000	280,294,000
Weighted Average Interest Rate	1.48%	1.59%
Prime broker arrangement
Short-term Debt [Line Items]
Oustanding Balance	127,754,000	234,417,000
Weighted Average Interest Rate	0.91%	0.90%
Bank lines (secured)
Short-term Debt [Line Items]
Oustanding Balance	$12,000,000	$0
Weighted Average Interest Rate	1.50%

ShortTerm_Financing_Additional

Short-Term Financing - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Short-term Debt [Line Items]
Excess net capital	164,300,000
Short-term financing	377,767,000	514,711,000
Commercial paper (secured)
Short-term Debt [Line Items]
Number of commercial paper programs	3
Short-term financing	238,013,000	280,294,000
Commercial paper (secured) | Minimum
Short-term Debt [Line Items]
Debt term	27 days
Commercial paper (secured) | Maximum
Short-term Debt [Line Items]
Debt term	270 days
Commercial paper (secured) | CP Series A | Weighted Average
Short-term Debt [Line Items]
Debt term	77 days
Commercial paper (secured) | CP Series II A | Weighted Average
Short-term Debt [Line Items]
Debt term	26 days
Commercial paper (secured) | CP Series III A
Short-term Debt [Line Items]
Excess net capital	120,000,000
Commercial paper (secured) | CP Series III A | Weighted Average
Short-term Debt [Line Items]
Debt term	27 days
Bank lines (secured)
Short-term Debt [Line Items]
Short-term financing	12,000,000	0
Bank lines (secured) | Committed Credit Facility [Member]
Short-term Debt [Line Items]
Debt term	1 year
Line of credity, maximum borrowing capacity	250,000,000
Short-term financing	0
Bank lines (secured) | Uncommitted Credit Facility [Member]
Short-term Debt [Line Items]
Line of credity, maximum borrowing capacity	185,000,000
Short-term financing	12,000,000
Number of banks	2

Variable_Rate_Senior_Notes_Add

Variable Rate Senior Notes - Additional Information (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Nov. 30, 2012	Jun. 02, 2014
		class
Senior Notes
Debt Instrument [Line Items]
Note purchase agreement, days to pay interest	5 days
Note purchase agreement, event of default, maximum indebtedness	$10,000,000
Senior Notes
Debt Instrument [Line Items]
Face amount		125,000,000
Number of classes of notes		2
Minimum net capital required	120,000,000
Senior Notes | Class A Variable Rate Senior Notes Due May 2014 [Member]
Debt Instrument [Line Items]
Face amount		50,000,000
Senior Notes | Class A Variable Rate Senior Notes Due May 2017
Debt Instrument [Line Items]
Face amount			50,000,000
Senior Notes | Class A Variable Rate Senior Notes Due May 2017 | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	3.00%
Reference rate	P3M
Senior Notes | Class B Variable Rate Senior Notes Due November 2015
Debt Instrument [Line Items]
Face amount		$75,000,000
Senior Notes | Class B Variable Rate Senior Notes Due November 2015 | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	4.50%
Reference rate	P3M

Bank_Syndicated_Financing_Addi

Bank Syndicated Financing - Additional Information (Detail) (Bank Syndicated Financing [Member], USD $)	0 Months Ended
	Dec. 29, 2010
Debt Instrument [Line Items]
Debt term	3 years
Term Loan
Debt Instrument [Line Items]
Bank syndicated financing	100,000,000
Revolving credit facility
Debt Instrument [Line Items]
Revolving credit facility	50,000,000

Contingencies_Commitments_and_1

Contingencies, Commitments, and Guarantees - Aggregate Minimum Lease Commitments under Operating Leases (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Commitments and Contingencies Disclosure [Abstract]
2015	$12,313,000
2016	12,052,000
2017	9,958,000
2018	9,646,000
2019	9,099,000
Thereafter	26,463,000
Total	79,531,000
Rentals Received Under Noncancelable Subleases	7,200,000
Operating Leases, Rent Expense	$13,800,000	$12,900,000	$13,100,000

Contingencies_Commitments_and_2

Contingencies, Commitments, and Guarantees - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Commitments and Contingencies Disclosure [Abstract]
Litigation Related Reserve Activity, Net	$0.80	($4.10)	$0.90
Remaining Capital Commitments To Investment Vehicles	$37.30

Restructuring_Additional_Infor

Restructuring - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Restructuring Cost and Reserve [Line Items]
Restructuring-related expense	$3.60	$3.60
Contract Termination
Restructuring Cost and Reserve [Line Items]
Restructuring-related expense	0.7
Leased Office Space
Restructuring Cost and Reserve [Line Items]
Restructuring-related expense	0.5	1.2
Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring-related expense	$2.40	$2.40

Shareholders_Equity_Additional

Shareholders' Equity - Additional Information (USD $)	12 Months Ended			9 Months Ended	3 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Dec. 31, 2012	Sep. 30, 2010	Sep. 30, 2014
Equity, Class of Treasury Stock [Line Items]
Aggregate purchase price	$10,854,000	$71,462,000	$47,164,000
Shares of common stock purchased from restricted stock award related to recipients' employment tax obligations	256,055	386,713	385,449
Repurchase of common stock for employee tax withholding	10,854,000	15,533,000	9,097,000
Common stock, shares authorized	100,000,000	100,000,000
Common stock, par value	$0.01	$0.01
Preferred stock, shares authorized	5,000,000
Preferred stock, par value	$0.01
Common stock, number of votes per share	1
Number of common stock issued for retirement plan obligations	103,598	96,049	165,241
Issuance of treasury shares for 401k match	4,156,000	3,939,000	3,814,000
Reissuance of treasury shares as a result of employee vesting	774,194	786,467
2010 Plan
Equity, Class of Treasury Stock [Line Items]
Repurchase of common stock, authorized amount						75,000,000
Treasury Stock, Shares, Acquired				1,488,881
Treasury Stock Acquired, Average Cost Per Share				$22.48
Aggregate purchase price				33,500,000
2012 Plan
Equity, Class of Treasury Stock [Line Items]
Repurchase of common stock, authorized amount				100,000,000
Treasury Stock, Shares, Acquired		1,719,662			156,577
Treasury Stock Acquired, Average Cost Per Share		$32.52			$29.38
Aggregate purchase price		55,923,000			4,600,000
2014 Plan
Equity, Class of Treasury Stock [Line Items]
Repurchase of common stock, authorized amount							$100,000,000

Noncontrolling_Interests_Addit

Noncontrolling Interests - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Noncontrolling Interest [Line Items]
Noncontrolling interests	$149,548,000	$147,396,000
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	0	0	0
Municipal bond fund
Noncontrolling Interest [Line Items]
Noncontrolling interests	117,000,000	126,300,000
Merchant banking fund
Noncontrolling Interest [Line Items]
Noncontrolling interests	24,700,000	14,100,000
Other private equity investments
Noncontrolling Interest [Line Items]
Noncontrolling interests	$7,800,000	$7,000,000

Employee_Benefit_Plans_Additio

Employee Benefit Plans - Additional Information (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule of Defined Benefit Plans And Defined Contribution Plans Disclosures [Table] [Line Items]
Employee Benefit Expense	$13.20	$12.10	$13
Retirement Savings Plan
Schedule of Defined Benefit Plans And Defined Contribution Plans Disclosures [Table] [Line Items]
Maximum 401(k) Plan Contribution Rates As Percentage Of Employees Earnings	100.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	6.00%
Health and Welfare Plans
Schedule of Defined Benefit Plans And Defined Contribution Plans Disclosures [Table] [Line Items]
Employee Benefit Expense	$7.70	$7.20	$8

Compensation_Plans_Summary_of_

Compensation Plans - Summary of Outstanding Equity Awards (Details)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock or units outstanding	1,095,305
Stock options outstanding	217,873	469,289	486,563	502,623
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock or units outstanding	1,095,305	1,582,062	2,322,438	3,152,001
Leadership grants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock or units outstanding	405,826	290,536	173,271	0
Amended And Restated 2003 Annual And Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding	217,873
Amended And Restated 2003 Annual And Long-Term Incentive Plan | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock or units outstanding	1,066,146
Amended And Restated 2003 Annual And Long-Term Incentive Plan | Sign On Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock or units outstanding	259,984
Amended And Restated 2003 Annual And Long-Term Incentive Plan | Annual Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock or units outstanding	806,162
Amended And Restated 2003 Annual And Long-Term Incentive Plan | Leadership grants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock or units outstanding	405,826
Employment Inducement Award Plan 2010 | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock or units outstanding	29,159

Compensation_Plans_RSU_Valuati

Compensation Plans - RSU Valuation Assumptions (Details) (Restricted Stock Units)	12 Months Ended
	Dec. 31, 2014
Grant Year 2014
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 $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Unvested Restricted Stock or Stock Units
Ending Balance	1,095,305
Restricted Stock
Unvested Restricted Stock or Stock Units
Beginning Balance	1,582,062	2,322,438	3,152,001
Granted	421,728	682,760	635,136
Vested	-883,761	-1,165,989	-1,309,881
Cancelled	-24,724	-257,147	-154,818
Ending Balance	1,095,305	1,582,062	2,322,438
Weighted Average Grant Date Fair Value (in dollars per share)
Beginning Balance	$35.25	$37.01	$38.79
Granted	$40.57	$38.35	$22.89
Vested	$36.22	$39.83	$34.21
Cancelled	$36.02	$38.30	$39.37
Ending Balance	$36.51	$35.25	$37.01

Compensation_Plans_Unvested_Re1

Compensation Plans - Unvested Restricted Stock Units (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Unvested Restricted Stock or Stock Units
Ending Balance	1,095,305
Leadership grants
Unvested Restricted Stock or Stock Units
Beginning Balance	290,536	173,271	0
Granted	115,290	117,265	214,526
Vested	0	0	0
Cancelled	0	0	-41,255
Ending Balance	405,826	290,536	173,271
Weighted Average Grant Date Fair Value (in dollars per share)
Beginning Balance	$15.83	$12.12	$0
Granted	$23.42	$21.32	$12.12
Vested	$0	$0	$0
Cancelled	$0	$0	$12.12
Ending Balance	$17.99	$15.83	$12.12

Compensation_Plans_Stock_Optio

Compensation Plans - Stock Options (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Options Outstanding
Beginning Balance	469,289	486,563	502,623
Granted	0	0	0
Exercised	-137,864	0	0
Cancelled	-55	-17,274	-16,060
Expired	113,497
Ending Balance	217,873	469,289	486,563	502,623
Options exercisable at period end	217,873	469,289	486,563
Weighted Average Exercise Price (in dollars per share)
Beginning Balance	$44.83	$44.76	$44.71
Granted	$0	$0	$0
Exercised	$39.55	$0	$0
Cancelled	$39.62	$42.85	$43.17
Expired	$47.72
Ending Balance	$46.66	$44.83	$44.76	$44.71
Options exercisable at period end	$46.66	$44.83	$44.76
Weighted Average Remaining Contractual Term (in Years)
Weighted Average Remaining Contractual Term (in Years)	2 years	2 years	2 years 10 months 24 days	3 years 10 months 24 days
Options exercisable at period end	2 years	2 years	2 years 10 months 24 days
Aggregate Intrinsic Value
Aggregate Intrinsic Value of Stock Options	$3,066,839	$288,318	$94,150	$0
Options exercisable at end of period	$3,066,839	$288,318	$94,150

Compensation_Plans_Additional_

Compensation Plans - Additional Stock Option Activity (Details) (USD $)	12 Months Ended
	Dec. 31, 2014
$28.01
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, upper	$28.01
Options outstanding, shares	11,426
Options outstanding, weighted average contractual life (in Years)	4 months
Options outstanding, weighted average exercise price	$28.01
Exercisable options, shares	11,426
Exercisable options, weighted average exercise price	$28.01
$33.40
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, upper	$33.40
Options outstanding, shares	4,001
Options outstanding, weighted average contractual life (in Years)	7 months
Options outstanding, weighted average exercise price	$33.40
Exercisable options, shares	4,001
Exercisable options, weighted average exercise price	$33.40
$39.62
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, upper	$39.62
Options outstanding, shares	44,543
Options outstanding, weighted average contractual life (in Years)	37 days
Options outstanding, weighted average exercise price	$39.62
Exercisable options, shares	44,543
Exercisable options, weighted average exercise price	$39.62
$41.09
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, upper	$41.09
Options outstanding, shares	99,147
Options outstanding, weighted average contractual life (in Years)	3 years 1 month 6 days
Options outstanding, weighted average exercise price	$41.09
Exercisable options, shares	99,147
Exercisable options, weighted average exercise price	$41.09
$47.30 - $51.05
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, lower	$47.30
Range of exercise prices, upper	$51.05
Options outstanding, shares	11,343
Options outstanding, weighted average contractual life (in Years)	1 year 1 month 6 days
Options outstanding, weighted average exercise price	$47.85
Exercisable options, shares	11,343
Exercisable options, weighted average exercise price	$47.85
$70.13 - $70.65
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, lower	$70.13
Range of exercise prices, upper	$70.65
Options outstanding, shares	47,413
Options outstanding, weighted average contractual life (in Years)	1 year 10 months 24 days
Options outstanding, weighted average exercise price	$70.26
Exercisable options, shares	47,413
Exercisable options, weighted average exercise price	$70.26

Compensation_Plans_Additional_1

Compensation Plans - Additional Information (Detail) (USD $)	12 Months Ended				0 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2015	15-May-12	Dec. 31, 2010
	plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock-based compensation plans	2
Compensation expense related to employee restricted stock awards	$28,200,000	$21,000,000	$20,200,000
Forfeitures recorded as a result of violating post-termination restrictions	700,000	1,000,000	1,300,000
Tax benefit related to compensation costs for stock-based compensation arrangements	11,000,000	8,200,000	7,900,000
Intrinsic value of options exercised	1,700,000
Resulting tax benefit realized	700,000
Shares of common stock purchased from restricted stock award related to recipients' employment tax obligations	256,055	386,713	385,449
2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock purchased from restricted stock award related to recipients' employment tax obligations				200,000
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares granted, share	421,728	682,760	635,136
Fair value of restricted stock vested during the period	32,000,000	46,400,000	44,800,000
Unrecognized compensation cost related to restricted stock	10,200,000
Weighted average period over which restricted stock expense expected to be recognized	2 years 4 months 26 days
Annual Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period in years	3 years
Annual grant expense period	1 year
Sign On Grant | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Sign on grants requisite service period	2 years
Sign On Grant | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Sign on grants requisite service period	5 years
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Sign on grants requisite service period					3 years
Award earning percentage based on peer group	50.00%
Award earning percentage based on shareholder return	50.00%
Restricted stock units, performance period					36 months
Number of years risk free interest rate	3 years
Restricted shares granted, share	115,290	117,265	214,526
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to restricted stock	0
Stock options | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of stock options	10 years
Amended And Restated 2003 Annual And Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity award grants authorized	7,000,000
Shares available for future issuance	1,000,000
Employment Inducement Award Plan 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period in years						5 years
Restricted shares granted to ARI employees, value						$7,000,000
Restricted shares granted, share						158,801

Compensation_Plans_Compensatio

Compensation Plans Compensation Plans - Deferred Compensation Plans (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014
Nonqualified Deferred Compensation Plan
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Deferred compensation plan assets	6.6
Deferred compensation plan liabilities	6.6
Mutual Fund Restricted Shares Investment Plan
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Deferred compensation awards vesting period	3 years
New Employees | Mutual Fund Restricted Shares Investment Plan | Minimum
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Deferred compensation requisite service period	2 years
New Employees | Mutual Fund Restricted Shares Investment Plan | Maximum
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Deferred compensation requisite service period	5 years

Earnings_Per_Share_Details

Earnings Per Share (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Net income from continuing operations	$12,543	$14,668	$18,213	$17,748	$27,952	$6,851	$4,359	$10,667	$63,172	$49,829	$47,075
Net loss from discontinued operations	0	0	0	0	-818	-1,529	-1,871	-521	0	-4,739	-5,807
Net income applicable to Piper Jaffray Companies	12,543	14,668	18,213	17,748	27,134	5,322	2,488	10,146	63,172	45,090	41,268
Earnings allocated to participating securities (1)									5,031	4,494	5,933
Net income applicable to Piper Jaffray Companies' common shareholders	$11,700	$13,552	$16,717	$16,089	$24,445	$4,826	$2,266	$8,966	$58,141	$40,596	$35,335
Shares for basic and diluted calculations:
Average shares used in basic computation	15,241,000	15,066,000	14,958,000	14,612,000	14,378,000	14,641,000	15,621,000	15,582,000	14,971,000	15,046,000	15,615,000
Average shares used in diluted computation	15,293,000	15,129,000	15,013,000	14,657,000	14,397,000	14,626,000	15,626,000	15,610,000	15,025,000	15,061,000	15,616,000
Earnings/(loss) per basic common share
Income from continuing operations	$0.77	$0.90	$1.12	$1.10	$1.75	$0.42	$0.25	$0.60	$3.88	$2.98	$2.58
Loss from discontinued operations	$0	$0	$0	$0	($0.05)	($0.09)	($0.11)	($0.03)	$0	($0.28)	($0.32)
Earnings per basic common share	$0.77	$0.90	$1.12	$1.10	$1.70	$0.33	$0.15	$0.58	$3.88	$2.70	$2.26
Earnings/(loss) per diluted common share
Income from continuing operations	$0.77	$0.90	$1.11	$1.10	$1.75	$0.42	$0.25	$0.60	$3.87	$2.98	$2.58
Loss from discontinued operations	$0	$0	$0	$0	($0.05)	($0.09)	($0.11)	($0.03)	$0	($0.28)	($0.32)
Earnings per diluted common share	$0.77	$0.90	$1.11	$1.10	$1.70	$0.33	$0.15	$0.57	$3.87	$2.70	$2.26
Weighted average participating shares outstanding									1,299,827	1,667,067	2,622,438
Stock options
Shares for basic and diluted calculations:
Stock options									54,000	15,000	1,000

Segment_Reporting_Reportable_S

Segment Reporting - Reportable Segment Financial Results (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Investment banking									$369,811	$248,563	$232,958
Institutional sales and trading									156,809	146,648	166,642
Total management and performance fees									85,062	83,045	65,699
Investment income									12,813	21,566	4,903
Net revenues	150,548	159,426	170,031	168,133	187,576	128,314	99,772	109,533	648,138	525,195	488,952
Non-interest expenses	129,059	133,734	139,614	135,420	145,524	116,254	96,439	91,365	537,827	449,582	419,941
Pre-tax operating income	21,489	25,692	30,417	32,713	42,052	12,060	3,333	18,168	110,311	75,613	69,011
Pre-tax operating margin									17.00%	14.40%	14.10%
Intangible asset amortization expense									9,272	7,993	6,944
Capital Markets
Segment Reporting Information [Line Items]
Investment banking									370,591	248,928	233,447
Institutional sales and trading									174,411	167,444	187,215
Total management and performance fees									5,398	3,891	1,678
Investment income									24,046	30,404	9,840
Long-term financing expenses									6,655	7,420	7,982
Net revenues									567,791	443,247	424,198
Non-interest expenses									478,661	393,231	371,628
Segment pre-tax operating income/(loss)									89,130	50,016	52,570
Pre-tax operating margin									15.70%	11.30%	12.40%
Intangible asset amortization expense									2,972	1,349	0
Capital Markets | Equities
Segment Reporting Information [Line Items]
Investment banking									116,684	100,224	73,180
Capital Markets | Debt
Segment Reporting Information [Line Items]
Investment banking									67,731	74,284	74,102
Capital Markets | Advisory services
Segment Reporting Information [Line Items]
Investment banking									186,176	74,420	86,165
Capital Markets | Equities
Segment Reporting Information [Line Items]
Institutional sales and trading									82,211	91,169	75,723
Capital Markets | Fixed income
Segment Reporting Information [Line Items]
Institutional sales and trading									92,200	76,275	111,492
Asset Mgmt [Member]
Segment Reporting Information [Line Items]
Management fees									78,772	71,314	63,236
Performance fees									892	7,840	785
Total management and performance fees									79,664	79,154	64,021
Investment income									683	2,794	733
Net revenues									80,347	81,948	64,754
Non-interest expenses									59,166	56,351	48,313
Segment pre-tax operating income/(loss)									21,181	25,597	16,441
Pre-tax operating margin									26.40%	31.20%	25.40%
Intangible asset amortization expense									$6,300	$6,644	$6,944

Segment_Reporting_Net_Revenues

Segment Reporting - Net Revenues by Geographic Locations (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Net revenues	$150,548	$159,426	$170,031	$168,133	$187,576	$128,314	$99,772	$109,533	$648,138	$525,195	$488,952
United States
Segment Reporting Information [Line Items]
Net revenues									632,625	513,433	476,718
Europe
Segment Reporting Information [Line Items]
Net revenues									$15,513	$11,762	$12,234

Segment_Reporting_LongLived_As

Segment Reporting - Long-Lived Assets By Geographic Region (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Long-Lived Assets by Geographical Areas [Line Items]
Long Lived Assets	$305,937	$302,930
United States
Long-Lived Assets by Geographical Areas [Line Items]
Long Lived Assets	300,421	296,516
Europe
Long-Lived Assets by Geographical Areas [Line Items]
Long Lived Assets	$5,516	$6,414

Net_Capital_Requirements_and_O1

Net Capital Requirements and Other Regulatory Matters - Additional Information (Detail) (USD $)	Dec. 31, 2014
Schedule Of Compliance With Regulatory Capital Requirements For Broker Dealer [Line Items]
Alternative Net Capital Requirement	$1,000,000
Alternative Net Capital Requirement Percentage Of Net Capital To Aggregate Debits	2.00%
Percentage Of Net Capital To Aggregate Debits Under Restriction On Business Expansion Or Dividend Payment	5.00%
Net Capital	165,300,000
Excess net capital	164,300,000
Senior Notes
Schedule Of Compliance With Regulatory Capital Requirements For Broker Dealer [Line Items]
Minimum Net Capital Required	120,000,000
Commercial Paper [Member] | CP Series III A 1 [Member]
Schedule Of Compliance With Regulatory Capital Requirements For Broker Dealer [Line Items]
Excess net capital	120,000,000
Committed Credit Facility [Member]
Schedule Of Compliance With Regulatory Capital Requirements For Broker Dealer [Line Items]
Minimum Net Capital Required	120,000,000
Committed Credit Facility [Member] | Senior Notes
Schedule Of Compliance With Regulatory Capital Requirements For Broker Dealer [Line Items]
Minimum Net Capital Required	$120,000,000

Income_Taxes_Components_of_Inc

Income Taxes - Components of Income Tax Expense (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Current:
Federal									$37,331	$20,468	$16,939
State									8,117	3,795	-9,563
Foreign									161	183	0
Current Income Tax Expense (Benefit), Total									45,609	24,446	7,376
Deferred:
Federal									-8,641	-1,582	7,735
State									-1,317	-4,041	4,413
Foreign									335	1,567	-54
Deferred Income Tax Expense (Benefit)									-9,623	-4,056	12,094
Total income tax expense from continuing operations	7,514	8,596	10,049	9,827	10,260	2,886	1,644	5,600	35,986	20,390	19,470
Total income tax benefit from discontinued operations									$0	($2,935)	($23,795)

Income_Taxes_Reconciliation_of

Income Taxes - Reconciliation of Federal Income Taxes at Statutory Rates to Effective Tax Rates (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Federal income tax expense/(benefit) at statutory rates									$38,609	$26,464	$24,153
State income taxes, net of federal tax benefit									3,857	2,785	2,540
Net tax-exempt interest income									-3,693	-3,917	-3,353
Foreign jurisdictions tax rate differential									-63	-185	-164
Change in valuation allowance									0	-4,182	-1,110
Restricted stock deferred tax asset write-off									0	0	4,577
Income attributable to noncontrolling interests									-3,903	-1,888	-863
Other, net									1,179	1,313	-6,310
Total income tax expense from continuing operations	$7,514	$8,596	$10,049	$9,827	$10,260	$2,886	$1,644	$5,600	$35,986	$20,390	$19,470

Income_Taxes_Net_Deferred_Tax_

Income Taxes - Net Deferred Tax Asset Included in Other Assets on Consolidated Statements of Financial Condition (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Deferred tax assets:
Deferred compensation	$56,893	$43,608
Net operating loss carry forwards	4,854	5,569
Liabilities/accruals not currently deductible	1,601	1,903
Other	2,930	1,459
Total deferred tax assets	66,278	52,539
Valuation allowance	-159	-159
Deferred tax assets after valuation allowance	66,119	52,380
Deferred tax liabilities:
Goodwill amortization	15,028	9,957
Unrealized gains on firm investments	3,221	3,577
Fixed assets	945	1,017
Other	1,074	1,577
Total deferred tax liabilities	20,268	16,128
Net deferred tax assets	$45,851	$36,252

Income_Taxes_Changes_in_Amount

Income Taxes - Changes in Amount of Unrecognized Tax Benefits (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	$2,200	$290	$8,915
Additions based on tax positions related to the current year	0	0	0
Additions for tax positions of prior years	123	2,000	200
Reductions for tax positions of prior years	0	-90	-8,825
Settlements	0	0	0
Ending Balance	$2,323	$2,200	$290

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	$300,000
Valuation allowance	-159,000	-159,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense			0
Changes in income tax expense due to unrecognized tax benefits decreases			-7,400,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	200,000	200,000
Reductions for tax positions of prior years	0	90,000	8,825,000
Unrecognized Tax Benefits Interest on Income Taxes Expense Reversal			$2,600,000

Piper_Jaffray_Companies_Parent1

Piper Jaffray Companies (Parent Company only) - Condensed Statements of Financial Condition (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Assets
Cash and cash equivalents	$15,867	$123,683	$105,371	$85,024
Other assets	100,299	102,092
Total assets	2,623,917	2,318,157
Liabilities and Shareholders’ Equity
Variable rate senior notes	125,000	125,000
Accrued compensation	228,877	159,928
Other liabilities and accrued expenses	43,151	58,385
Total liabilities	1,654,457	1,436,085
Total common shareholders’ equity	819,912	734,676
Total liabilities and shareholders’ equity	2,623,917	2,318,157
Parent Company
Assets
Cash and cash equivalents	200	336	1,069	14,493
Investment in and advances to subsidiaries	956,609	870,104
Other assets	13,819	9,119
Total assets	970,628	879,559
Liabilities and Shareholders’ Equity
Variable rate senior notes	125,000	125,000
Accrued compensation	24,618	18,454
Other liabilities and accrued expenses	1,098	1,429
Total liabilities	150,716	144,883
Total common shareholders’ equity	819,912	734,676
Total liabilities and shareholders’ equity	$970,628	$879,559

Piper_Jaffray_Companies_Parent2

Piper Jaffray Companies (Parent Company only) - Condensed Statements of Operations (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues:
Interest									$48,716	$50,409	$37,845
Total revenues	157,394	165,947	175,976	173,894	193,893	134,506	106,520	115,312	673,211	550,231	508,047
Net revenues	150,548	159,426	170,031	168,133	187,576	128,314	99,772	109,533	648,138	525,195	488,952
Expenses:
Total non-interest expenses	129,059	133,734	139,614	135,420	145,524	116,254	96,439	91,365	537,827	449,582	419,941
Income tax expense	7,514	8,596	10,049	9,827	10,260	2,886	1,644	5,600	35,986	20,390	19,470
Net income	13,975	17,096	20,368	22,886	30,974	7,645	-182	12,047	74,325	50,484	43,734
Net income/(loss) from continuing operations	12,543	14,668	18,213	17,748	27,952	6,851	4,359	10,667	63,172	49,829	47,075
Income/(loss) from discontinued operations, net of tax	0	0	0	0	-818	-1,529	-1,871	-521	0	-4,739	-5,807
Net income applicable to Piper Jaffray Companies	12,543	14,668	18,213	17,748	27,134	5,322	2,488	10,146	63,172	45,090	41,268
Parent Company
Revenues:
Dividends from subsidiaries									50,333	46,000	119,000
Interest									662	254	82
Other revenues									275	198	0
Total revenues									51,270	46,452	119,082
Interest expense									5,463	5,850	5,823
Net revenues									45,807	40,602	113,259
Expenses:
Total non-interest expenses									5,318	3,096	4,222
Income from continuing operations before income tax expense and equity in undistributed/(distributed in excess of) income of subsidiaries									40,489	37,506	109,037
Income tax expense									14,795	13,263	39,175
Net income									25,694	24,243	69,862
Equity in undistributed/(distributed in excess of) income of subsidiaries									37,478	25,200	-49,617
Net income/(loss) from continuing operations									63,172	49,443	20,245
Income/(loss) from discontinued operations, net of tax									0	-4,353	21,023
Net income applicable to Piper Jaffray Companies									$63,172	$45,090	$41,268

Piper_Jaffray_Companies_Parent3

Piper Jaffray Companies (Parent Company only) - Condensed Statements of Cash Flows (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating Activities:
Net income/(loss)	$63,172	$45,090	$41,268
Adjustments to reconcile net income/(loss) to net cash provided by operating activities:
Share-based and deferred compensation	28,764	21,598	20,641
Net cash provided by/(used in) operating activities	-50,069	42,163	-211,782
Investing Activities:
Repayment of FAMCO note	2,000	250	0
Net cash provided by/(used in) investing activities	-5,387	-29,952	-2,131
Financing Activities:
Issuance of variable rate senior notes	50,000	0	125,000
Decrease in bank syndicated financing	0	0	-115,000
Repurchase of common stock	-10,854	-71,462	-47,164
Net cash provided by/(used in) financing activities	-52,017	5,798	234,277
Net increase/(decrease) in cash and cash equivalents	-107,816	18,312	20,347
Cash and cash equivalents at beginning of year	123,683	105,371	85,024
Cash and cash equivalents at end of year	15,867	123,683	105,371
Supplemental disclosures of cash flow information Cash received/(paid) during the year for:
Interest	-25,345	-23,487	-19,357
Income taxes	-58,599	-745	4,961
Parent Company
Operating Activities:
Net income/(loss)	63,172	45,090	41,268
Adjustments to reconcile net income/(loss) to net cash provided by operating activities:
Share-based and deferred compensation	180	60	240
Equity distributed in excess of/(in undistributed) income of subsidiaries	-37,478	-25,200	49,617
Net cash provided by/(used in) operating activities	25,874	19,950	91,125
Investing Activities:
Repayment of FAMCO note	2,000	250	0
Net cash provided by/(used in) investing activities	2,000	250	0
Financing Activities:
Issuance of variable rate senior notes	50,000	0	125,000
Repayment of variable rate senior notes	-50,000	0	0
Decrease in bank syndicated financing	0	0	-115,000
Advances from/(to) subsidiaries	-28,010	34,996	-76,481
Repurchase of common stock	0	-55,929	-38,068
Net cash provided by/(used in) financing activities	-28,010	-20,933	-104,549
Net increase/(decrease) in cash and cash equivalents	-136	-733	-13,424
Cash and cash equivalents at beginning of year	336	1,069	14,493
Cash and cash equivalents at end of year	200	336	1,069
Supplemental disclosures of cash flow information Cash received/(paid) during the year for:
Interest	-4,801	-5,596	-5,741
Income taxes	($14,795)	($13,263)	($39,175)

Quarterly_Information_unaudite2

Quarterly Information (unaudited) (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Quarterly Financial Information Disclosure [Abstract]
Total revenues	$157,394	$165,947	$175,976	$173,894	$193,893	$134,506	$106,520	$115,312	$673,211	$550,231	$508,047
Interest expense	6,846	6,521	5,945	5,761	6,317	6,192	6,748	5,779	25,073	25,036	19,095
Net revenues	150,548	159,426	170,031	168,133	187,576	128,314	99,772	109,533	648,138	525,195	488,952
Non-interest expenses	129,059	133,734	139,614	135,420	145,524	116,254	96,439	91,365	537,827	449,582	419,941
Income from continuing operations before income tax expense	21,489	25,692	30,417	32,713	42,052	12,060	3,333	18,168	110,311	75,613	69,011
Income tax expense	7,514	8,596	10,049	9,827	10,260	2,886	1,644	5,600	35,986	20,390	19,470
Net income from continuing operations	13,975	17,096	20,368	22,886	31,792	9,174	1,689	12,568	74,325	55,223	49,541
Loss from discontinued operations, net of tax	0	0	0	0	-818	-1,529	-1,871	-521	0	-4,739	-5,807
Net income	13,975	17,096	20,368	22,886	30,974	7,645	-182	12,047	74,325	50,484	43,734
Net income applicable to noncontrolling interests	1,432	2,428	2,155	5,138	3,840	2,323	-2,670	1,901	11,153	5,394	2,466
Net income applicable to Piper Jaffray Companies	12,543	14,668	18,213	17,748	27,134	5,322	2,488	10,146	63,172	45,090	41,268
Net income applicable to Piper Jaffray Companies' common shareholders	11,700	13,552	16,717	16,089	24,445	4,826	2,266	8,966	58,141	40,596	35,335
Amounts applicable to Piper Jaffray Companies
Net income/(loss) from continuing operations	12,543	14,668	18,213	17,748	27,952	6,851	4,359	10,667	63,172	49,829	47,075
Net loss from discontinued operations	$0	$0	$0	$0	($818)	($1,529)	($1,871)	($521)	$0	($4,739)	($5,807)
Earnings/(loss) per basic common share
Income from continuing operations	$0.77	$0.90	$1.12	$1.10	$1.75	$0.42	$0.25	$0.60	$3.88	$2.98	$2.58
Loss from discontinued operations	$0	$0	$0	$0	($0.05)	($0.09)	($0.11)	($0.03)	$0	($0.28)	($0.32)
Earnings per basic common share	$0.77	$0.90	$1.12	$1.10	$1.70	$0.33	$0.15	$0.58	$3.88	$2.70	$2.26
Earnings/(loss) per diluted common share
Income from continuing operations	$0.77	$0.90	$1.11	$1.10	$1.75	$0.42	$0.25	$0.60	$3.87	$2.98	$2.58
Loss from discontinued operations	$0	$0	$0	$0	($0.05)	($0.09)	($0.11)	($0.03)	$0	($0.28)	($0.32)
Earnings per diluted common share	$0.77	$0.90	$1.11	$1.10	$1.70	$0.33	$0.15	$0.57	$3.87	$2.70	$2.26
Weighted average number of common shares outstanding
Basic	15,241	15,066	14,958	14,612	14,378	14,641	15,621	15,582	14,971	15,046	15,615
Diluted	15,293	15,129	15,013	14,657	14,397	14,626	15,626	15,610	15,025	15,061	15,616