Entity Central Index Key Equity investments, at fair value, unrealized gain (loss). Trading securities, unrealized gain (loss). -- None. No documentation exists for this element. -- Document And Entity Information [Abstract] Entities [Table] Entities [Table] Class of Stock Statement Class Of Stock [Axis] Class of Stock Class Of Stock [Domain] Common Class A Common Class A [Member] Common Class B Common Class B [Member] Entity Information [Line Items] Entity Information [Line Items] Entity Registrant Name Entity Registrant Name Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Entity Small Business Entity Small Business Entity Emerging Growth Company Entity Emerging Growth Company Entity Shell Company Entity Shell Company Document Type Document Type Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Trading Symbol Trading Symbol Amendment Flag Amendment Flag Entity Current Reporting Status Entity Current Reporting Status Entity File Number Entity File Number Entity Tax Identification Number Entity Tax Identification Number Entity Address, Address Line One Entity Address Address Line1 Entity Address, City or Town Entity Address City Or Town Entity Address, State or Province Entity Address State Or Province Entity Address, Country Entity Address Country Entity Address, Postal Zip Code Entity Address Postal Zip Code City Area Code City Area Code Local Phone Number Local Phone Number Entity Common Stock, Shares Outstanding Entity Common Stock Shares Outstanding Carrying value as of the balance sheet date of the portion of certain deferred tax assets which are or will be payable to the selling and converting shareholders per a tax receivable agreement. Statement Of Financial Position [Abstract] Statement [Table] Statement [Table] Statement [Line Items] Statement [Line Items] ASSETS Assets [Abstract] Cash and Cash Equivalents ($3,778 and $3,733)1 Cash And Cash Equivalents At Carrying Value Restricted Cash Restricted Cash And Cash Equivalents Due from Broker ($255 and $16)1 Receivables From Brokers Dealers And Clearing Organizations Advisory Fees Receivable Accounts Receivable Net Investments ($4,101 and $3,295)1 Investments Receivable from Related Parties Due From Related Parties Other Receivables ($12 and $13)1 Other Receivables Prepaid Expenses and Other Assets Prepaid Expense And Other Assets Right-of-use Assets Operating Lease Right Of Use Asset Deferred Tax Asset Deferred Tax Assets Net Property and Equipment, Net of Accumulated Depreciation of $4,234 and $3,724, respectively Property Plant And Equipment Net TOTAL ASSETS Assets LIABILITIES AND EQUITY Liabilities And Stockholders Equity [Abstract] Liabilities: Liabilities [Abstract] Accounts Payable and Accrued Expenses ($13 and $15)1 Accounts Payable And Accrued Liabilities Current And Noncurrent Due to Broker ($83 and $4)1 Payables To Broker Dealers And Clearing Organizations Liability to Selling and Converting Shareholders Liability To Selling And Converting Shareholders Lease Liabilities Operating Lease Liability Deferred Compensation Liability Deferred Compensation Liability Current And Noncurrent Other Liabilities Other Liabilities TOTAL LIABILITIES Liabilities Commitments and Contingencies (see Note 12) Commitments And Contingencies Equity: Stockholders Equity Including Portion Attributable To Noncontrolling Interest [Abstract] Preferred Stock (Par Value $0.01; 200,000,000 Shares Authorized; None Outstanding) Preferred Stock Value Common Stock Common Stock Value Additional Paid-In Capital Additional Paid In Capital Common Stock Retained Earnings Retained Earnings Accumulated Deficit Accumulated Other Comprehensive Income Accumulated Other Comprehensive Income Loss Net Of Tax Total Pzena Investment Management, Inc.'s Equity Stockholders Equity Non-Controlling Interests Minority Interest TOTAL EQUITY Stockholders Equity Including Portion Attributable To Noncontrolling Interest TOTAL LIABILITIES AND EQUITY Liabilities And Stockholders Equity Variable Interest Entities Variable Interest Entities By Classification Of Entity [Axis] Variable Interest Entity, Classification Classification Of Variable Interest Entity [Domain] Variable Interest Entity, Primary Beneficiary Variable Interest Entity Primary Beneficiary [Member] Cash Due from Broker Investments Other Receivables Property and equipment, accumulated depreciation Accumulated Depreciation Depletion And Amortization Property Plant And Equipment Accounts Payable and Accrued Expenses Due to Broker Preferred Stock, Par Value (in dollars per share) Preferred Stock Par Or Stated Value Per Share Preferred Stock, Shares Authorized (in shares) Preferred Stock Shares Authorized Preferred Stock, Shares Outstanding (in shares) Preferred Stock Shares Outstanding Common Stock, Par Value (in dollars per share) Common Stock Par Or Stated Value Per Share Common Stock, Shares Authorized (in shares) Common Stock Shares Authorized Common Stock, Shares Issued (in shares) Common Stock Shares Issued Common Stock, Shares Outstanding (in shares) Common Stock Shares Outstanding Income Statement [Abstract] REVENUE Revenue From Contract With Customer Including Assessed Tax EXPENSES Operating Expenses [Abstract] Compensation and Benefits Expense Labor And Related Expense General and Administrative Expense General And Administrative Expense Total Operating Expenses Operating Expenses Operating Income Operating Income Loss OTHER INCOME Nonoperating Income Expense [Abstract] Interest Income Investment Income Interest Dividend Income Investment Income Dividend Net Realized and Unrealized (Losses)/ Gains from Investments Gain Loss On Investments Equity in Earnings/ (Losses) of Affiliates Income Loss From Equity Method Investments Other (Expense)/ Income Other Nonoperating Income Expense Total Other Income/ (Expense) Nonoperating Income Expense Income Before Income Taxes Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest Income Tax Expense Income Tax Expense Benefit Net Income Profit Loss Less: Net Income Attributable to Non-Controlling Interests Net Income Loss Attributable To Noncontrolling Interest Net Income Attributable to Pzena Investment Management, Inc. Net Income Loss Net Income for Basic Earnings per Share Net Income Loss Available To Common Stockholders Basic Basic Earnings per Share Earnings Per Share Basic Basic Weighted Average Shares Outstanding Weighted Average Number Of Shares Outstanding Basic Net Income for Diluted Earnings per Share Net Income Loss Attributable To Parent Diluted Diluted Earnings per Share Earnings Per Share Diluted Diluted Weighted Average Shares Outstanding Weighted Average Number Of Diluted Shares Outstanding Cash Dividends per Share of Class A Common Stock Common Stock Dividends Per Share Declared Statement Of Income And Comprehensive Income [Abstract] NET INCOME OTHER COMPREHENSIVE LOSS Other Comprehensive Income Loss Net Of Tax Period Increase Decrease [Abstract] Foreign Currency Translation Adjustment Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax Total Other Comprehensive Loss Other Comprehensive Income Loss Net Of Tax Comprehensive Income Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest Less: Comprehensive Income Attributable to Non-Controlling Interests Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest Total Comprehensive Income Attributable to Pzena Investment Management, Inc. Comprehensive Income Net Of Tax This element represents the shares of recognized equity-based compensation related to stock options and nonvested shares during the period, that is, the amount recognized as expense in the income statement. This element represents the amount of recognized equity-based compensation related to stock options and nonvested shares during the period, that is, the amount recognized as expense in the income statement. This element represents the amount of recognized equity-based remuneration related to directors shares during the period, that is, the amount recognized as expense in the income statement. Equity impact of the value of stock that has been retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital). Adjustments to additional paid in capital tax impact of transactions with non-controlling shareholders. Statement Of Stockholders Equity [Abstract] Accumulated Other Comprehensive (Loss)/ Income Statement Equity Components [Axis] Equity Component Equity Component [Domain] Additional Paid-In Capital Additional Paid In Capital [Member] Accumulated Other Comprehensive (Loss)/ Income Accumulated Other Comprehensive Income [Member] Retained Earnings Retained Earnings [Member] Non-Controlling Interests Noncontrolling Interest [Member] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase Decrease In Stockholders Equity Roll Forward Beginning Balance Beginning Balance (in shares) Amortization of Non-Cash Compensation Adjustments To Additional Paid In Capital And Non Controlling Interests Sharebased Compensation Requisite Service Period Recognition Value Amortization of Non-Cash Compensation (in shares) Adjustments To Additional Paid In Capital And Non Controlling Interests Sharebased Compensation Requisite Service Period Recognition Shares Issuance of Shares under Equity Incentive Plan Stock Issued During Period Value New Issues Issuance of Shares under Equity Incentive Plan (in shares) Stock Issued During Period Shares New Issues Sale of Shares under Equity Incentive Plan Stock Issued During Period Value Employee Stock Ownership Plan Sale of Shares under Equity Incentive Plan (in shares) Stock Issued During Period Shares Employee Stock Ownership Plan Directors' Share Grants Adjustments To Additional Paid In Capital And Non Controlling Interests Sharebased Director Shares Remuneration Requisite Service Period Recognition Value Net Income Foreign Currency Translation Adjustments Temporary Equity Foreign Currency Translation Adjustments Repurchase and Retirement of Class A Common Stock Stock Repurchased And Retired During Period Value Repurchase and Retirement Shares/Units (in shares) Stock Repurchased And Retired During Period Shares Repurchase and Retirement of Class B Units Stock Retired And Repurchased During Period Value Class A Cash Dividends Declared and Paid ($0.49 per share) Dividends Common Stock Cash Tax Impact of Transactions with Non-Controlling Shareholders Adjustments To Additional Paid In Capital Tax Impact Of Transactions With Non Controlling Shareholders Contributions from Non-Controlling Interests Noncontrolling Interest Increase From Subsidiary Equity Issuance Contributions to Non-Controlling Interests Minority Interest Decrease From Redemptions Distributions to Non-Controlling Interests Minority Interest Decrease From Distributions To Noncontrolling Interest Holders Other Adjustments To Additional Paid In Capital Other Ending Balance Ending Balance (in shares) Class A Cash Dividends Declared and Paid (in USD per share) Common Stock Dividends Per Share Cash Paid The aggregate amount of noncash, equity-based director remuneration. This may include the value of stock or unit options or amortization of restricted stock or units for directors' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method. Accretion discount Non-cash lease expense. Increase decrease in lease liability. The cash outflow associated with the purchase of investments associated with deferred compensation during the period. The cash inflow associated with the sale of investments associated with deferred compensation during the period. Statement Of Cash Flows [Abstract] OPERATING ACTIVITIES Net Cash Provided By Used In Operating Activities [Abstract] Adjustments to Reconcile Net Income to Cash Provided by Operating Activities: Adjustments To Reconcile Net Income Loss To Cash Provided By Used In Operating Activities [Abstract] Depreciation Depreciation Non-Cash Compensation Share Based Compensation Directors' Share Grants Director Shares Net Realized and Unrealized Losses/ (Gains) from Investments Equity in (Earnings)/ Losses of Affiliates Accretion of Discount Accretion Discount Non-Cash Lease Expense Non Cash Lease Expense Foreign Currency Translation Adjustments Foreign Currency Transaction Gain Loss Before Tax Deferred Income Taxes Deferred Income Tax Expense Benefit Changes in Operating Assets and Liabilities: Increase Decrease In Operating Capital [Abstract] Advisory Fees Receivable Increase Decrease In Accounts Receivable Due from Broker Increase Decrease In Brokerage Receivables Prepaid Expenses and Other Assets Increase Decrease In Prepaid Deferred Expense And Other Assets Due to Broker Increase Decrease In Payables To Broker Dealers Accounts Payable, Accrued Expenses, and Other Liabilities Increase Decrease In Accounts Payable And Accrued Liabilities Lease Liabilities Increase Decrease In Lease Liability Purchases of Equity Securities Payments For Purchase Of Securities Operating Activities Proceeds from Equity Securities Proceeds From Sale Of Securities Operating Activities Net Cash Provided by Operating Activities Net Cash Provided By Used In Operating Activities INVESTING ACTIVITIES Net Cash Provided By Used In Investing Activities [Abstract] Purchases of Investments Purchases Of Deferred Compensation Investments Proceeds from Sale of Investments Proceeds From Sale Of Deferred Compensation Investments Payments (to)/ from Related Parties Increase Decrease In Due From Related Parties Purchases of Property and Equipment Payments To Acquire Property Plant And Equipment Net Cash (Used in)/ Provided by Investing Activities Net Cash Provided By Used In Investing Activities FINANCING ACTIVITIES Net Cash Provided By Used In Financing Activities [Abstract] Repurchase and Retirement of Class A Common Stock Payments For Repurchase Of Common Stock Repurchase and Retirement of Class B Units Payments For Repurchase Of Other Equity Sale of Shares under Equity Incentive Plan Proceeds From Issuance Or Sale Of Equity Distributions to Non-Controlling Interests Payments Of Dividends Minority Interest Contributions from Non-Controlling Interests Proceeds From Payments To Minority Shareholders Dividends Payments Of Dividends Net Cash Used in Financing Activities Net Cash Provided By Used In Financing Activities NET CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CASH, CASH EQUIVALENTS AND RESTRICTED CASH - Beginning of Period Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Net Change in Cash, Cash Equivalents and Restricted Cash CASH, CASH EQUIVALENTS AND RESTRICTED CASH - End of Period Supplementary Cash Flow Information: Supplemental Cash Flow Information [Abstract] Issuances of Shares under Equity Incentive Plan Stock Issued1 Income Taxes Paid Income Taxes Paid Organization Consolidation And Presentation Of Financial Statements [Abstract] Organization Organization Consolidation And Presentation Of Financial Statements Disclosure [Text Block] Accounting Policies [Abstract] Significant Accounting Policies Basis Of Presentation And Significant Accounting Policies [Text Block] Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] Compensation and Benefits Disclosure Of Compensation Related Costs Share Based Payments [Text Block] Compensation And Retirement Disclosure [Abstract] Employee Benefit Plans Pension And Other Postretirement Benefits Disclosure [Text Block] Earnings Per Share [Abstract] Earnings per Share Earnings Per Share [Text Block] Stockholders Equity Note [Abstract] Shareholders' Equity Stockholders Equity Note Disclosure [Text Block] Noncontrolling Interest [Abstract] Non-Controlling Interests Minority Interest Disclosure [Text Block] Investments Debt And Equity Securities [Abstract] Investments Investments In Debt And Marketable Equity Securities And Certain Trading Assets Disclosure [Text Block] Fair Value Disclosures [Abstract] Fair Value Measurements Fair Value Disclosures [Text Block] Property Plant And Equipment [Abstract] Property and Equipment Property Plant And Equipment Disclosure [Text Block] Related Party Transactions [Abstract] Related Party Transactions Related Party Transactions Disclosure [Text Block] Commitments And Contingencies Disclosure [Abstract] Commitments and Contingencies Commitments And Contingencies Disclosure [Text Block] Income Tax Disclosure [Abstract] Income Taxes Income Tax Disclosure [Text Block] Subsequent Events [Abstract] Subsequent Events Subsequent Events [Text Block] Basis of Presentation Basis Of Accounting Policy Policy [Text Block] Accounting Pronouncements Adopted in 2019 and Recently Issued Accounting Pronouncements Not Yet Adopted New Accounting Pronouncements Policy Policy [Text Block] Management's Use of Estimates Use Of Estimates Revenue Recognition Revenue Recognition Policy [Text Block] Cash and Cash Equivalents Cash And Cash Equivalents Policy [Text Block] Restricted Cash Cash And Cash Equivalents Restricted Cash And Cash Equivalents Policy Disclosure of accounting policy for recognition of primarily amounts payable/receivable from unsettled securities. Due to/from Broker Due To From Broker Policy [Text Block] Non-Cash Compensation Share Based Compensation Option And Incentive Plans Policy Investments Investment Policy [Text Block] Securities Valuation Marketable Securities Policy Concentrations of Credit Risk Concentration Risk Credit Risk Property and Equipment Property Plant And Equipment Policy [Text Block] Leases Lessor Leases Policy [Text Block] Share repurchases policy. Share Repurchases Share Repurchases Policy [Text Block] Business Segments Segment Reporting Policy Policy [Text Block] Income Taxes Income Tax Policy [Text Block] Tax receivable agreement. Tax Receivable Agreement Tax Receivable Agreement Policy Policy [Text Block] Foreign Currency Foreign Currency Transactions And Translations Policy [Text Block] Fair Value Measurements Fair Value Measurement Policy Policy [Text Block] A tabular disclosure of the ownership percentage of entities as of the balance sheet date. Summary of entities Summary Of Entities Table [Text Block] Disaggregation of Revenue Disaggregation Of Revenue Table [Text Block] Schedule of Cash and Cash Equivalents Schedule Of Cash And Cash Equivalents Table [Text Block] Schedule of Restricted Cash Schedule Of Restricted Cash And Cash Equivalents [Text Block] Tabular disclosure of the amount of cash compensation, other benefits and total share-based compensation cost, including the amounts attributable to each share-based compensation plan and any related tax benefits. Summary of compensation and benefits expense to employees and members Schedule Of Compensation And Benefits Expense To Employees And Members Table [Text Block] Schedule of share based compensation activity Schedule Of Share Based Compensation Activity Table [Text Block] Summary of basic earnings per share Schedule Of Earnings Per Share Basic By Common Class [Text Block] A tabular disclosure of the computation of diluted net income. Summary of diluted net income Summary Of Diluted Net Income Table [Text Block] Summary of diluted earnings per share Schedule Of Earnings Per Share Diluted By Common Class [Text Block] The tabular disclosure of the parent's ownership interest in subsidiary net income or loss. Non-controlling interest income Consolidation Less Than Wholly Owned Subsidiary Parent Ownership Income Interest Table [Text Block] Summary of investments Investment Table [Text Block] Investments, at Fair Value Trading Securities And Certain Trading Assets [Text Block] Schedule of Fair Value Measurements Fair Value Assets Measured On Nonrecurring Basis [Text Block] Property and equipment Property Plant And Equipment [Text Block] Lease expense and supplemental cash flow information. Components of Operating Lease Expense and Supplemental Cash Flow Information Lease Expense And Supplemental Cash Flow Information Table [Text Block] Tabular disclosure of components operating leases. Information Regarding Operating Leases Operating Leases Table [Text Block] Maturities of Lease Liabilities Lessee Operating Lease Liability Maturity Table [Text Block] Legal Entity Legal Entity [Axis] Entity Entity [Domain] Pzena Investment Management, Pty. Pzena Investment Management, Pty Pzena Investment Management Pty [Member] Pzena Financial Services, LLC [Member] Pzena Financial Services, LLC Pzena Financial Services L L C [Member] Pzena Investment Management, LTD. Pzena Investment Management, LTD Pzena Investment Management L T D [Member] Pzena U.S. Best Ideas (GP), LLC [Member] Pzena U.S. Best Ideas (GP), LLC Pzena U S Best Ideas G P L L C [Member] Pzena Global Best Ideas (GP), LLC. Pzena Global Best Ideas (GP), LLC Pzena Global Best Ideas G P L L C [Member] Pzena Investment Management Special Situations, LLC. Pzena Investment Management Special Situations, LLC Pzena Investment Management Special Situations Llc [Member] Pzena international small cap value fund, a series of advisors series trust [Member]. Pzena International Small Cap Value Fund, a Series of Advisors Series Trust Pzena International Small Cap Value Fund Series Of Advisors Series Trust [Member] Pzena International Value Service. Pzena International Value Service, a series of Pzena Investment Management International, LLC Pzena International Value Service [Member] Type of Entity (Date of Formation) Entity Legal Form Operating company's ownership Equity Method Investment Ownership Percentage Schedule Of Variable Interest Entities [Table] Schedule Of Variable Interest Entities [Table] Investment, Name Schedule Of Equity Method Investment Equity Method Investee Name [Axis] Investment, Name Equity Method Investee Name [Domain] VIEs that are not consolidated continue to receive investment management services from the Company, and are vehicles through which the Company offers its Global Value and/or EAFE Value strategies. VIEs that are not consolidated Vies That Are Not Consolidated [Member] Variable Interest Entity [Line Items] Variable Interest Entity [Line Items] Equity method investment, assets Equity Method Investment Summarized Financial Information Assets Investments in firm-sponsored vehicles where we are not primary beneficiary Variable Interest Entity Nonconsolidated Carrying Amount Assets Maximum loss exposure Variable Interest Entity Entity Maximum Loss Exposure Amount [Line Items] for Significant Accounting Policies [Table] Significant Accounting Policies [Table] Significant Accounting Policies [Table] Significant Accounting Policies [Table] Adjustments for New Accounting Pronouncements Adjustments For New Accounting Pronouncements [Axis] Type of Adoption Type Of Adoption [Member] Accounting Standards Update 2016-02 Accounting Standards Update201602 [Member] Customer Major Customers [Axis] Customer Name Of Major Customer [Domain] Largest Customer [Member] Largest Customer Largest Customer [Member] Concentration Risk Type Concentration Risk By Type [Axis] Concentration Risk Type Concentration Risk Type [Domain] Customer Concentration Risk Customer Concentration Risk [Member] Concentration Risk Benchmark Concentration Risk By Benchmark [Axis] Concentration Risk Benchmark Concentration Risk Benchmark [Domain] Advisory fees Sales Revenue Net [Member] Property, Plant and Equipment, Type Property Plant And Equipment By Type [Axis] Property, Plant and Equipment, Type Property Plant And Equipment Type [Domain] Equipment Equipment [Member] Range Range [Axis] Range Range [Member] Minimum Minimum [Member] Maximum Maximum [Member] Significant Accounting Policies [Line Items] Significant Accounting Policies [Line Items] Right-of-use asset Lease liability In general, returns are calculated on an annualized basis over the contract's measurement period for the use in calculating performance fee income. Revenue Recognition Revenue Recognition [Abstract] Contract measurement period (in years) Usual Contract Measurement Period Disaggregation Of Revenue [Table] Disaggregation Of Revenue [Table] Product and Service Product Or Service [Axis] Product and Service Products And Services [Domain] Separately Managed Accounts, Asset-Based Fees [Member] Asset-Based Fees Separately Managed Accounts Asset Based Fees [Member] Separately Managed Accounts [Member] Separately Managed Accounts Separately Managed Accounts [Member] Sub-Advised Accounts, Asset-Based Fees [Member] Asset-Based Fees Sub Advised Accounts Asset Based Fees [Member] Sub-Advised Accounting, Decrease In Asset-Based Fees [Member] Decrease in Asset-Based Fees Sub Advised Accounting Decrease In Asset Based Fees [Member] Sub-Advised Accounting, Performance-Based Fees [Member] Performance-Based Fees Sub Advised Accounting Performance Based Fees [Member] Sub-Advised Fees [Member] Sub-Advised Accounts Sub Advised Fees [Member] Pzena Funds Fees, Asset-Based Fees [Member] Asset-Based Fees Pzena Funds Fees Asset Based Fees [Member] Pzena Funds, Expense Cap Reimbursements [Member] Expense Cap Reimbursements Pzena Funds Expense Cap Reimbursements [Member] Pzena Funds Fees, Performance-Based Fees [Member] Performance-Based Fees Pzena Funds Fees Performance Based Fees [Member] Pzena Funds Fees [Member] Pzena Funds Pzena Funds Fees [Member] Disaggregation of Revenue [Line Items] Disaggregation Of Revenue [Line Items] Revenues Cash and Cash Equivalents Cash And Cash Equivalents [Abstract] Total Impairment losses recognized Gain Loss On Sales Of Assets And Asset Impairment Charges Concentration of Credit Risk Concentration Risks Types No Concentration Percentage [Abstract] Concentration risk (percent) Concentration Risk Percentage1 Allowance for doubtful accounts receivable Allowance For Doubtful Accounts Receivable Property and equipment, useful life (years) Property Plant And Equipment Useful Life Lease term Lessee Operating Lease Term Of Contract Business Segments Segment Reporting Disclosure Of Other Information About Entitys Reportable Segments [Abstract] Number of operating segments (in segments) Number Of Operating Segments Tax Receivable Agreement: Valuation allowance on deferred tax assets Deferred Tax Assets Valuation Allowance The period of time the entity can deduct the step up in its tax basis in net assets acquired under Section 754 of the Internal Revenue Code. Pursuant to a tax receivable agreement signed between the members of the operating company and the Company, a percentage of the cash savings generated by this election will be distributed to the selling and converting shareholders upon the realization of this benefit. Percentage Of Cash Tax Savings In Income Tax If Realizes Company Expects To Benefit Section 754 election tax deduction period Section754 Election Tax Deduction Period Cash savings generated by this election will be distributed to selling and converting shareholders upon realization (in hundredth) Cash Savings Generated By This Election Will Be Distributed To Selling And Converting Shareholders Upon Realization Percentage of cash tax savings in income tax if realizes company expects to benefit Percentage Of Cash Tax Savings In Income Tax If Realizes Company Expects To Benefit Pursuant to a tax receivable agreement signed between the members of the operating company and the Company, a percentage of the cash savings generated by this election will be retained by the Company and will increase Additional Paid in Capital. Cash savings generated by this election will increase additional paid-in capital Cash Savings Generated By This Election Will Increase The Companys Additional Paidin Capital Other comprehensive loss associated with foreign currency translation adjustments Expenditures for salaries include all cash compensation to employees, officers, benefits and other related benefits. Cash Compensation and Other Benefits Cash Compensation And Other Benefits Total Compensation and Benefits Expense Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] Plan Name Plan Name [Axis] Plan Name Plan Name [Domain] Plan Name. Equity Incentive Plan 2006 Equity Incentive Plan2006 [Member] Award Type Award Type [Axis] Equity Award Share Based Compensation Arrangements By Share Based Payment Award Award Type And Plan Name [Domain] Restricted Class B Units Restricted Stock Units R S U [Member] Options To Purchase Delayed Exchange Class B Units [Member] Options To Purchase Delayed Exchange Class B Units Options To Purchase Delayed Exchange Class B Units [Member] Phantom Delayed Exchange Class B Units [Member] Phantom Delayed Exchange Class B Units Phantom Delayed Exchange Class B Units [Member] Delayed Exchange Unit [Member] Delayed Exchange Unit Delayed Exchange Unit [Member] Compensation Arrangements [Line Items] Share Based Compensation Arrangement By Share Based Payment Award [Line Items] Grants in period (in shares) Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Grants in period, weighted average grant date fair value (USD per share) Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Weighted Average Grant Date Fair Value Grants in period, weighted average grant date fair value (USD per share) Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value Vesting Vesting [Axis] Vesting Vesting [Domain] Represents options to purchase shares of Class A common stock issued whose vesting is contingent on meeting various departmental and company-wide performance goals, including revenue growth in excess of certain expenses. These share options contingently vest over a period of 7 years. Contingent Options to Purchase Shares of Class A Common Stock Contingent Options To Purchase Shares Of Class A Common Stock [Member] Plan name. 2007 Equity Incentive Plan Equity Incentive Plan2007 [Member] Amended and Restated Bonus Plan. Bonus plan Bonus Plan [Member] Incentive compensation awarded to employees consisting of a stated number of phantom shares or units. Phantom Shares of Class A common stock Phantom Shares Of Class Common Stock [Member] Title of Individual Title Of Individual [Axis] Relationship to Entity Title Of Individual With Relationship To Entity [Domain] Director Plan Director [Member] Cash compensation paid in the form of equity Stock Issued During Period Value Issued For Services Vesting period for units (in years) Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Period1 This element represents the amount of recognized equity-based issuances to employees during the period. Delayed Exchange Class B units issued (in shares) Delayed Exchange Class B units issued Adjustments To Additional Paid In Capital And Noncontrolling Interests Equity Issuance Contingently vesting options (in shares) Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested Number Of Shares Deferred compensation liability Company's directors have elected to defer percentage of their compensation in the form of phantom shares of Class A common stock under director plan. Deferred compensation percentage of compensation directors elected Defer Compensation Percentage Of Compensation Directors Elected Shares outstanding (in shares) Shares Outstanding Distributions made under Director Plan (in shares) Deferred Compensation Arrangement With Individual Shares Issued Unrecorded compensation expense Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Profit sharing and savings plan expenses recognized Defined Contribution Plan Cost Recognized Schedule Of Equity Method Investments [Table] Schedule Of Equity Method Investments [Table] Certain unvested share of Class A common stock granted to employees have nonforfeitable rights to dividend payments and therefore participate fully in the results of the Company from the date they are granted. They are included in the computation basic and diluted earnings per share using the two-class method for participating securities. Participating Shares of Restricted Class A Common Stock Participating Restricted Class A Common Stock [Member] Schedule Of Equity Method Investments [Line Items] Schedule Of Equity Method Investments [Line Items] Computation of basic earnings per share [Abstract] Earnings Per Share Basic [Abstract] Net Income for Basic Earnings per Share Basic Weighted Average Shares Outstanding (in shares) Basic Earnings per Share (in dollars per share) The assumed income tax expense of the operating company using the Company's, estimated using effective tax rate, exclusive of prior period adjustments and adjustments associated with both the valuation allowance and the liability to selling and converting shareholders. Non controlling interest. Pzena Investment Management, LLC Pzena Investment Management Llc [Member] Diluted Net Income [Abstract] Net Income Loss Attributable To Parent Diluted [Abstract] Net Income Attributable to Non-Controlling Interests Income Loss Attributable To Noncontrolling Interest Less: Assumed Corporate Income Taxes Assumed Corporate Income Tax Expense Net Income of Pzena Investment Management, Inc. Diluted Net Income The sum of restricted units used in the calculation of the diluted per-share or per-unit computation. Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method. Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method. The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period. Unvested Class B Units granted to employees have nonforfeitable rights to dividend equivalent distributions and therefore participate fully in the results of the operating company's operations from the date they are granted. They are included in the computation diluted earnings per share using the two-class method for participating securities. Participating Class B Units Participating Class B Restricted Units [Member] Antidilutive Securities Antidilutive Securities Excluded From Computation Of Earnings Per Share By Antidilutive Securities [Axis] Antidilutive Securities, Name Antidilutive Securities Name [Domain] Options to purchase operating company class b units during the period. Options to Purchase Class B Units Options To Purchase Operating Company Class B Units [Member] Excluded from the calculation of diluted net income per share, as their inclusion would have had an antidilutive effect for the respective periods. Options to Purchase Shares of Class A Common Stock Options To Purchase Shares Of Class Common Stock [Member] Diluted Net Income Allocated to: Total Diluted Net Income Attributable to Shareholders Net Income Loss Available To Common Stockholders Diluted Total Basic Weighted-Average Shares Outstanding (in shares) Dilutive Effect of B Units (in shares) Participating Class B Restricted Units Dilutive Effect of Options (in shares) Incremental Common Shares Attributable To Share Based Payment Arrangements Dilutive Effect of Phantom Class B Units & Phantom Shares of Class A Common Stock (in shares) Dilutive Effect Of Phantom Units Dilutive Effect of Restricted Shares of Class A Common Stock (in shares) Dilutive Effect Of Restricted Shares Of Class Common Stock Diluted Weighted Average Common Shares Outstanding (in shares) Diluted Weighted Average Common Shares Outstanding Participating Class B Units (in shares) Weighted Average Number Diluted Shares Outstanding Adjustment Diluted Weighted-Average Shares Outstanding (in shares) Diluted Earnings per Share (in dollars per share) Antidilutive securities excluded from diluted EPS (in shares) Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount Common stock holders ownership percentage of entity. Schedule Of Stock By Class [Table] Schedule Of Stock By Class [Table] Ownership Ownership [Axis] Ownership Ownership [Domain] Class of Stock [Line Items] Class Of Stock [Line Items] Economic interest held in company by class of stock (in hundredths) Common Stock Holders Ownership Percentage Of Entity Economic interest held in company by class of stock (in hundredths) Minority Interest Ownership Percentage By Parent Number of Votes The percentage of stock holding to the number of all shares of common stock outstanding that will entitle holders one vote Voting rights for the stock once the threshold has been crossed. Par value (in dollars per share) Voting rights (in votes) Number Of Votes Percentage of stock holding that will entitle holders to one vote (in hundredths) Percentage Of Stock Holding That Will Entitle Holders To One Vote Voting rights when class of stock constitutes less than 20% of all shares outstanding (in votes) Voting Rights After Threshold Is Crossed The outstanding shares of the Company's Class A common stock represent the rights of the holders of all classes of the Company's capital stock to receive distributions Percentage of outstanding shares that represents rights of holders to receive distribution (in hundredths) Percentage Of Outstanding Shares Rights For Distribution Amount authorized under stock repurchase program Stock Repurchase Program Authorized Amount1 Common stock purchased and retired (in shares) Purchased under repurchase authorization at an average price per share (in dollars per share) Treasury Stock Acquired Average Cost Per Share Minority Interest [Table] Minority Interest [Table] Non-Controlling Interests of Pzena Investment Management, LLC Non controlling interests. Non-Controlling Interests of Consolidated Subsidiaries Consolidated Subsidiaries [Member] Noncontrolling Interest [Line Items] Minority Interest [Line Items] Net Income Attributable to Non-Controlling Interests Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table] Investment Type Investment Type [Axis] Investments Investment Type Categorization [Member] Equity Securities Equity Securities [Member] Mutual Funds Mutual Fund [Member] U.S. Treasury Bills U S Treasury Bill Securities [Member] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] Total Equity Investments, at Fair Value Equity Method Investments Fair Value Disclosure Total Trading Securities Trading Securities Debt Investments in Equity Method Investees Equity Method Investments Total Equity investments, at fair value, cost. Trading securities, amortized cost. Fair Value By Balance Sheet Grouping [Table] Fair Value By Balance Sheet Grouping [Table] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] Equity Investments, at Fair Value, Cost Equity Investments At Fair Value Cost Equity Investments, at Fair Value, Unrealized Gain/(Loss) Equity Investments At Fair Value Unrealized Gain Loss Equity Investments, at Fair Value Trading Securities, Amortized Cost Trading Securities Amortized Cost Trading Securities Unrealized Gain Loss Trading Securities Unrealized Gain Loss Investments in equity method investees Measurement Basis Fair Value By Measurement Basis [Axis] Fair Value Disclosure Item Amounts [Default] Portion At Fair Value Fair Value Disclosure [Member] Fair Value Measurement Fair Value Disclosure Item Amounts [Domain] Fair Value Estimate Of Fair Value Fair Value Disclosure [Member] Money Market Funds Money Market Funds [Member] Corporate Bonds Corporate Bond Securities [Member] Fair Value Hierarchy and NAV Fair Value By Fair Value Hierarchy Level [Axis] Fair Value Hierarchy and NAV Fair Value Measurements Fair Value Hierarchy [Domain] Level 1 Fair Value Inputs Level1 [Member] Level 2 Fair Value Inputs Level2 [Member] Level 3 Fair Value Inputs Level3 [Member] Cash Equivalents Cash And Cash Equivalents Fair Value Disclosure Trading Securities Total Assets Fair Value Disclosure Schedule Of Property Plant And Equipment [Table] Schedule Of Property Plant And Equipment [Table] Leasehold Improvements Leasehold Improvements [Member] Furniture and Fixtures Furniture And Fixtures [Member] Computer Hardware Computer Equipment [Member] Computer Software Computer Software Intangible Asset [Member] Office Equipment Office Equipment [Member] Property Plant And Equipment [Line Items] Property Plant And Equipment [Line Items] Property and equipment, gross Property Plant And Equipment Gross Accumulated Depreciation and Amortization Total Income Statement Location Income Statement Location [Axis] Income Statement Location Income Statement Location [Domain] General and Administrative Expense General And Administrative Expense [Member] Depreciation expense Schedule Of Related Party Transactions By Related Party [Table] Schedule Of Related Party Transactions By Related Party [Table] Related Party Related Party Transactions By Related Party [Axis] Related Party Related Party [Domain] VIEs That are Not Consolidated Variable Interest Entity Not Primary Beneficiary Aggregated Disclosure [Member] Related party transaction. Employees Employees [Member] Pzena Mutual Funds [Member] Pzena Mutual Funds Pzena Mutual Funds [Member] Related party transactions. Company's Executive Officers and Other Employees Company S Executive Officers And Other Employees [Member] Related Party Transaction [Line Items] Related Party Transaction [Line Items] Investment advisory fees Loan Write-off Period Loan write-off period Loan Writeoff Period Loans to employees Due From Employees Current Fees waived for providing investment management services to employees and other related parties. Investment advisory fees waived Investment Advisory Fees Waived Other Commitments [Table] Other Commitments [Table] Other Commitments [Line Items] Other Commitments [Line Items] Claims or payments to agreements Loss Contingency Accrual Payments Accrual made in consolidated financial statements Loss Contingency Accrual At Carrying Value Prior notice period for cancellation of sublease agreement. Operating Leases, Income Statement, Expected Annual Sublease Revenue Operating leases, contract term Lessor Operating Lease Term Of Contract Company or sublessee, prior notice period for cancellation of sublease agreement Prior Notice Period For Cancellation Of Sublease Agreement Expected annual sublease income Operating Leases Income Statement Expected Annual Sublease Revenue Lease expenses Operating Lease Expense Short-term lease expense Short Term Lease Cost Sublease income Sublease Income Leases [Abstract] Operating lease expense Cash paid for amounts included in the measurement of lease liabilities: Cash Flow Operating Activities Lessee [Abstract] Operating cash flows from operating leases Operating Lease Payments Right-of-use assets obtained in exchange for lease obligations Right Of Use Asset Obtained In Exchange For Operating Lease Liability Sublease Income Operating Leases Income Statement Sublease Revenue Operating lease right-of-use assets Operating lease liabilities Weighted-average remaining lease term (in years) Operating Lease Weighted Average Remaining Lease Term1 Weighted-average discount rate Operating Lease Weighted Average Discount Rate Percent Operating Leases Operating Lease Liabilities Payments Due [Abstract] 2019 (excluding the six months ended June 30, 2019) Lessee Operating Lease Liability Payments Remainder Of Fiscal Year 2020 Lessee Operating Lease Liability Payments Due Next Twelve Months 2021 Lessee Operating Lease Liability Payments Due Year Two 2022 Lessee Operating Lease Liability Payments Due Year Three 2023 Lessee Operating Lease Liability Payments Due Year Four 2024 Lessee Operating Lease Liability Payments Due Year Five Thereafter Lessee Operating Lease Liability Payments Due After Year Five Total undiscounted lease payments Lessee Operating Lease Liability Payments Due Less discount Lessee Operating Lease Liability Undiscounted Excess Amount Percentage Of Operating Company's Earnings Not Subject To Corporate-Level Taxes Effective tax rate Effective Income Tax Rate Continuing Operations Economic interest held in company by class of stock (in hundredths) Percentage Of Operating Companys Earnings Not Subject To Corporate Level Taxes Unrecognized tax benefits Unrecognized Tax Benefits Interest related to unrecognized tax benefits Unrecognized Tax Benefits Interest On Income Taxes Accrued Penalty accruals Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued Deferred tax assets Subsequent Event [Table] Subsequent Event [Table] Common Class A and Class B Common Class A and Class B Common Class A And Class B [Member] Subsequent Event Type Subsequent Event Type [Axis] Subsequent Event Type Subsequent Event Type [Domain] Subsequent Event Subsequent Event [Member] Subsequent Event [Line Items] Subsequent Event [Line Items] Cash dividends declared (in dollars per share) Dividend declared date Dividends Payable Date Declared Day Month And Year Dividend payable date Dividend Payable Date To Be Paid Day Month And Year Dividend record date Dividends Payable Date Of Record Day Month And Year Cash dividends payable (in dollars per share) Dividends Payable Amount Per Share