Business Acquisition [Axis] Business Acquisition [Axis] Partner Type of Partners' Capital Account, Name [Domain] Partner Type of Partners' Capital Account, Name [Domain] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Total lease liabilities Lessee, Operating Lease, Liability, to be Paid Net income (loss) Net income (loss) Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Related Party Transactions [Abstract] Consolidated funds Variable Interest Entity, Primary Beneficiary [Member] Deferred income tax assets Deferred Income Tax Assets, Net Revolver Long-Term Debt, Gross LIBOR Rate Multiplied By Statutory Reserve Rate LIBOR Rate Multiplied By Statutory Reserve Rate [Member] LIBOR Rate Multiplied By Statutory Reserve Rate Legacy Entities Legacy Entities [Member] Legacy Entities Contingent consideration obligations Business Combination, Contingent Consideration, Liability [Member] Business Combination, Contingent Consideration, Liability Entity Address, Postal Zip Code Entity Address, Postal Zip Code General Partner General Partner [Member] Earn-out (up to) Business Combination, Contingent Consideration Arrangements, Change in Range of Outcomes, Contingent Consideration, Liability, Value, High Greenspring Greenspring [Member] Greenspring Tax Receivable Agreement Tax Receivable Agreement [Member] Tax Receivable Agreement Preferred stock, shares outstanding (in shares) Preferred Stock, Shares Outstanding Valuation Technique, Discounted Cash Flow Valuation Technique, Discounted Cash Flow [Member] Total compensation and benefits Compensation And Benefits Expense Compensation And Benefits Expense Business Combinations Business Combinations Policy [Policy Text Block] Accounts payable, accrued expenses and other liabilities Accounts Payable and Other Accrued Liabilities AUD Screen Rate Multiplied By Statutory Reserve Rate AUD Screen Rate Multiplied By Statutory Reserve Rate [Member] AUD Screen Rate Multiplied By Statutory Reserve Rate Dividends paid to common stockholders Payments of Ordinary Dividends, Common Stock Expenses to related parties Related Party Transaction, Expenses from Transactions with Related Party Maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Income Tax Disclosure [Abstract] Due to affiliates Increase (Decrease) in Due to Related Parties Unrealized Unrealized performance fee-related compensation Performance Fee-Related Compensation Related to Carried Interest Allocation, Unrealized Performance Fee-Related Compensation Related to Carried Interest Allocation, Unrealized Additional paid-in capital Additional Paid in Capital Basis spread on variable interest rate Debt Instrument, Basis Spread on Variable Rate Class C Partnership units issued for Greenspring acquisition Partnership Units Issued For Acquisition Partnership Units Issued For Acquisition Other investing activities Payments for (Proceeds from) Other Investing Activities Statistical Measurement [Domain] Statistical Measurement [Domain] Exchange Two Exchange Two [Member] Exchange Two Thereafter Finite-Lived Intangible Asset, Expected Amortization, after Year Four Finite-Lived Intangible Asset, Expected Amortization, after Year Four Weighted-average discount rate for operating leases Operating Lease, Weighted Average Discount Rate, Percent Valuation Approach and Technique [Axis] Valuation Approach and Technique [Axis] Equity-Based Compensation Compensation Related Costs, Policy [Policy Text Block] Share-Based Payment Arrangement [Abstract] Exchange of Class B and Class C units for Class A common stock and redemption of corresponding Class B common shares Stock Issued During Period, Value, Conversion of Convertible Securities Number of classes of common stock outstanding Number Of Classes Of Common Stock Outstanding Number Of Classes Of Common Stock Outstanding Equity method investments: Equity Method Investment, Financial Statement, Reported Amounts [Abstract] Aggregate Purchase Price and Estimated Fair Values of Assets Acquired and Liabilities Assumed Schedule of Business Acquisitions, by Acquisition [Table Text Block] Other non-cash activities Other Noncash Income (Expense) Initial consolidation of legacy Greenspring general partner entities Noncontrolling Interest, Increase from Business Combination Net income (loss) attributable to StepStone Group Inc. Net income (loss) attributable to StepStone Group Inc. – Basic Net Income (Loss) Attributable to Parent Measurement Input Type [Domain] Measurement Input Type [Domain] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive securities excluded from computation of earnings per share (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Subsequent Event Type [Axis] Subsequent Event Type [Axis] Class B Partnership Unit Class B Partnership Unit [Member] Class B Partnership Unit Number of cities for leased offices Lessee, Operating Lease, Number Of Cities Lessee, Operating Lease, Number Of Cities Equity Component [Domain] Equity Component [Domain] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Net income (loss) per share of Class A common stock: Earnings Per Share Reconciliation [Abstract] Measurement Input, Discount Rate Measurement Input, Discount Rate [Member] Benefit from release of valuation allowance Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount Ownership [Axis] Ownership [Axis] Investment, Name [Domain] Investment, Name [Domain] Valuation Approach and Technique [Domain] Valuation Approach and Technique [Domain] Deferred financing costs Payments of Financing Costs Related Party [Domain] Related Party [Domain] Fair Value Measurements Fair Value Measurement, Policy [Policy Text Block] Supplemental disclosures: Supplemental Cash Flow Information [Abstract] Carried interest allocations, SMAs Carried Interest Allocation, Separately Managed Accounts [Member] Carried Interest Allocation, Separately Managed Accounts Number of operating segments Number of Operating Segments Class C Partnership Unit Class C Partnership Unit [Member] Class C Partnership Unit Remained of FY2023 Lessee, Operating Lease, Liability, to be Paid, Remainder of Fiscal Year Option pricing model inputs Liability Classified Awards, Measurement Input Liability Classified Awards, Measurement Input Statement of Cash Flows [Abstract] Entity Address, State or Province Entity Address, State or Province Level I Fair Value, Inputs, Level 1 [Member] Revenue, carried interest allocation, minimum return levels required Revenue, Carried Interest Allocation, Minimum Return Levels Required Revenue, Carried Interest Allocation, Minimum Return Levels Required Award Type [Axis] Award Type [Axis] Legacy Greenspring performance fee-related compensation Legacy Performance Fee-Related Compensation Related to Carried Interest Allocation Legacy Performance Fee-Related Compensation Related to Carried Interest Allocation New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Revenue since acquisition date Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual Settlements Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements Adjustments to reconcile net income (loss) to net cash provided by operating activities: Adjustments, Noncash Items, to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Advisory and other services Management And Advisory Fees, Net, Advisory And Other Services [Member] Management And Advisory Fees, Net, Advisory And Other Services Related Party Transaction [Domain] Related Party Transaction [Domain] Vesting of RSUs, net of shares withheld for employee taxes Stock Issued During Period, Value, Restricted Stock Award, Net of Shares Withheld For Employee Taxes Stock Issued During Period, Value, Restricted Stock Award, Net of Shares Withheld For Employee Taxes Other Liabilities Other Liabilities Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Expenses Costs and Expenses [Abstract] Partnership Partnership Of Subsidiary [Member] Partnership Of Subsidiary Swiss Average Rate Overnight Swiss Average Rate Overnight [Member] Swiss Average Rate Overnight Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table] Schedule of Equity Method Investments [Line Items] Schedule of Equity Method Investments [Line Items] Purchases of investments of Consolidated Funds Investments of Consolidated Funds, Cost Investments of Consolidated Funds, Cost Liability Class [Axis] Liability Class [Axis] Variable Interest Entity, Not Primary Beneficiary Variable Interest Entity, Not Primary Beneficiary [Member] Realized Carried Interest Allocation, Realized [Member] Carried Interest Allocation, Realized Accrued expenses and other liabilities Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Current Liabilities, Accrued Expenses And Other Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Current Liabilities, Accrued Expenses And Other Total liabilities Liabilities Liabilities Subsidiaries Subsidiaries [Member] Weighted-average remaining lease term for operating leases Operating Lease, Weighted Average Remaining Lease Term Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Geographical [Axis] Geographical [Axis] Cash flows from investing activities Net Cash Provided by (Used in) Investing Activities [Abstract] Realized Performance Fee-Related Compensation Related to Carried Interest Allocation, Realized Performance Fee-Related Compensation Related to Carried Interest Allocation, Realized Ownership percentage acquired Business Acquisition, Percentage of Voting Interests Acquired Class C Partnership units issued for Greenspring acquisition Stock Issued During Period, Value, New Issues Carried interest, contingent repayment obligations Equity Method Investment, Carried Interest Allocations, Maximum Amount Subject To Contingent Repayment Equity Method Investment, Carried Interest Allocations, Maximum Amount Subject To Contingent Repayment Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Compensation and benefits: Income Statement Compensation Expense Items [Abstract] Revolving credit facility Revolving Credit Facility [Member] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Maximum exposure to loss Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount Legacy carried interest allocation as percentage of cumulative fund or account performance Revenue, Legacy Carried Interest Allocation As Percentage Of Cumulative Fund Or Account Performance Revenue, Legacy Carried Interest Allocation As Percentage Of Cumulative Fund Or Account Performance Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Document Type Document Type Number of RSUs Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Variable Interest Entity, Not Primary Beneficiary, Subsidiaries Variable Interest Entity, Not Primary Beneficiary, Subsidiaries [Member] Variable Interest Entity, Not Primary Beneficiary, Subsidiaries Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Distributions received from investments Proceeds from Equity Method Investment, Distribution, Return of Capital Beginning balance (in dollars per share) Ending balance (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Debt Obligations Debt Disclosure [Text Block] SMAs Management And Advisory Fees, Net, Separately Managed Accounts [Member] Management And Advisory Fees, Net, Separately Managed Accounts Gain on remeasurement of lease liabilities Gain on remeasurement of lease liabilities Gain (Loss) On Remeasurement Of Lease Liabilities Gain (Loss) On Remeasurement Of Lease Liabilities Product and Service [Domain] Product and Service [Domain] Cash consideration, net of working capital adjustment Payments To Acquire Businesses, Net Of Working Capital Adjustment Payments To Acquire Businesses, Net Of Working Capital Adjustment Entity Shell Company Entity Shell Company Class B Common Stock Class B units Common Class B [Member] Investments: Investments [Abstract] Cash paid for amounts included in the measurement of lease liabilities: Cash Paid For Amounts Included In The Measurement Of Lease Liabilities [Abstract] Cash Paid For Amounts Included In The Measurement Of Lease Liabilities Management and advisory fees, net Management And Advisory Fees, Net [Member] Management And Advisory Fees, Net FY2024 Lessee, Operating Lease, Liability, to be Paid, Year One Stock issued for acquisition (in shares) Business Acquisition, Equity Interest Issued or Issuable, Number of Shares Non-controlling interest holders Affiliated Entity Legacy Funds Affiliated Entity [Member] Subsequent Event Subsequent Event [Member] Revenue Benchmark Revenue Benchmark [Member] Document Period End Date Document Period End Date Class C Common Stock Common Class C [Member] Legacy Greenspring investments in funds and accrued carried interest allocations Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Legacy Investments In Funds And Accrued Carried Interest Allocations Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Legacy Investments In Funds And Accrued Carried Interest Allocations Deferred offering costs Adjustments to Additional Paid in Capital, Stock Issued, Issuance Costs Schedule of Common Stock Outstanding [Roll Forward] Schedule of Common Stock Outstanding [Roll Forward] Schedule of Common Stock Outstanding Increase in deferred tax assets Increase (Decrease) In Deferred Tax Assets Increase (Decrease) In Deferred Tax Assets Unrealized carried interest allocations and investment (income) loss Carried Interest Allocation And Investment Income, Unrealized Gain (Loss) Carried Interest Allocation And Investment Income, Unrealized Gain (Loss) Schedule of Accumulated Other Comprehensive Income (Loss) Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Total assets Assets Assets Debt Disclosure [Abstract] Net income (loss) per share of Class A common stock: Earnings Per Share [Abstract] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Accrued compensation and benefits Employee-related Liabilities Net cash used in financing activities Net Cash Provided by (Used in) Financing Activities Accounting Policies [Abstract] Legacy Greenspring carried interest allocations Legacy Carried Interest Allocation [Member] Legacy Carried Interest Allocation Variable lease cost Variable Lease, Cost Credit Agreement Line of Credit [Member] New York Federal Reserve Bank Rate New York Federal Reserve Bank Rate [Member] New York Federal Reserve Bank Rate Income (loss) before income tax Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Change in deferred income taxes Deferred Income Taxes and Tax Credits Earnings Per Share Earnings Per Share [Text Block] Due to related parties, tax receivable agreements Due To Related Parties, Tax Receivable Agreements Due To Related Parties, Tax Receivable Agreements Purchase of non-controlling interests Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests Comprehensive income (loss) before non-controlling interests Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Related Party Transaction [Line Items] Related Party Transaction [Line Items] Award Type [Domain] Award Type [Domain] Unrecognized non-cash compensation, period of recognition Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Schedule of Intangible Assets, Net Schedule of Finite-Lived Intangible Assets [Table Text Block] Vesting of RSUs Stock Issued During Period, Value, Restricted Stock Award, Gross Cash consideration Payments to Acquire Businesses, Gross Legacy carried interest allocation, SMAs Legacy Carried Interest Allocation, Separately Managed Accounts [Member] Legacy Carried Interest Allocation, Separately Managed Accounts Entity Registrant Name Entity Registrant Name Subsequent Events Subsequent Events [Text Block] Numerator: Net Income (Loss) Available to Common Stockholders, Diluted [Abstract] Foreign currency translation adjustments Accumulated Foreign Currency Adjustment Attributable to Parent [Member] Client relationships Customer Relationships [Member] Entity Address, City or Town Entity Address, City or Town Legacy Greenspring investment income (loss) Legacy Investment Income Legacy Investment Income Total stockholders’ equity Total stockholders' equity, beginning balance Total stockholders' equity, ending balance Total stockholders' equity Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Consolidation Consolidation, Policy [Policy Text Block] Total carried interest allocations Revenue Not from Contract with Customer Share exchange, shares exchanged (in shares) Stockholders' Equity, Share Exchange, Shares Exchanged Stockholders' Equity, Share Exchange, Shares Exchanged Minimum Minimum [Member] Non-controlling interests Less: Amounts attributable to non-controlling interests Stockholders' Equity Attributable to Noncontrolling Interest Statement of Financial Position [Abstract] Entity Emerging Growth Company Entity Emerging Growth Company Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Investments of Consolidated Funds, Percent Of Total Investments Investments of Consolidated Funds, Percent Of Total Investments Investments of Consolidated Funds, Percent Of Total Investments Thereafter Lessee, Operating Lease, Liability, to be Paid, After Year Four Lessee, Operating Lease, Liability, to be Paid, After Year Four Less: Debt issuance costs Debt Issuance Costs, Net Commitments and Contingencies Disclosure [Abstract] Investment, Name [Axis] Investment, Name [Axis] Fair Value Measurements Fair Value Disclosures [Text Block] Distributions to non-controlling interests Payments of Ordinary Dividends, Noncontrolling Interest Trading Symbol Trading Symbol Entity File Number Entity File Number Share exchange, shares issued (in shares) Stockholders' Equity, Share Exchange, Shares Issued Stockholders' Equity, Share Exchange, Shares Issued Statement of Partners' Capital [Abstract] Class Of Partnership Unit [Axis] Class Of Partnership Unit [Axis] Class Of Partnership Unit FY2027 Finite-Lived Intangible Asset, Expected Amortization, Year Four Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Excluding Consolidated Funds Excluding Consolidated Funds [Member] Excluding Consolidated Funds Fair Value by Liability Class [Domain] Fair Value by Liability Class [Domain] Variable Interest Entities Variable Interest Entity Disclosure [Text Block] Granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period Restricted Stock Units (RSUs) Restricted Stock Units (RSUs) [Member] Entity Information [Line Items] Entity Information [Line Items] Effective tax rate Effective Income Tax Rate Reconciliation, Percent Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Unrealized Carried Interest Allocation, Unrealized [Member] Carried Interest Allocation, Unrealized Business Combinations Business Combination Disclosure [Text Block] Other comprehensive income (loss): Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract] Purchases of investments of Consolidated Funds Payments To Acquire Consolidated Funds Payments To Acquire Consolidated Funds EURIBOR Rate Multiplied By Statutory Reserve Rate Euro Interbank Offer Rate Multiplied By Statutory Reserve Rate [Member] Euro Interbank Offer Rate Multiplied By Statutory Reserve Rate London Interbank Offered Rate (LIBOR) London Interbank Offered Rate (LIBOR) [Member] Equity Method Investments and Joint Ventures [Abstract] Accrued deferred offering costs Stock Issuance Costs Incurred But Not Yet Paid Stock Issuance Costs Incurred But Not Yet Paid Balance, beginning of period: Balance, end of period: Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value Schedule of Variable Interest Entities [Table] Schedule of Variable Interest Entities [Table] Equity method investment, total accrued carried interest allocation percentage Concentration Risk, Percentage Subsequent Events [Abstract] Total revenues Total revenues Revenues Contingent consideration Business Combination, Consideration Transferred, Liabilities Incurred Net income attributable to StepStone Group Inc. Business Acquisition, Pro Forma Net Income (Loss) Income Taxes Income Tax Disclosure [Text Block] Proceeds from capital contributions from non-controlling interests Proceeds From Capital Contributions From Non-Controlling Interests Proceeds From Capital Contributions From Non-Controlling Interests Revenue from related parties Revenue from Related Parties Due to affiliates Due to Related Parties Credit Facility [Domain] Credit Facility [Domain] Amortization of intangible assets Amortization of Intangible Assets Less: Comprehensive income attributable to redeemable non-controlling interests in Consolidated Funds Comprehensive Income (Loss), Net Of Tax, Redeemable Noncontrolling Interest Comprehensive Income (Loss), Net Of Tax, Redeemable Noncontrolling Interest Basic (in dollars per share) Basic (in dollars per share) Earnings Per Share, Basic Contractual rights: service agreements Contractual Rights, Service Agreements [Member] Contractual Rights, Service Agreements New partnership interests, fair value Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Granted in Period, Fair Value Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Granted in Period, Fair Value FY2026 Lessee, Operating Lease, Liability, to be Paid, Year Three Investments of Consolidated Funds Investments of consolidated funds Investments of Consolidated Funds Investments of Consolidated Funds Cash-based compensation Compensation Expense, Cash Based Compensation And Benefits Compensation Expense, Cash Based Compensation And Benefits Schedule of Equity Method Investments [Table] Schedule of Equity Method Investments [Table] Accounting Standards Update and Change in Accounting Principle [Table] Accounting Standards Update and Change in Accounting Principle [Table] Unrealized gain on defined benefit plan, net Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Purchase of non-controlling interests Payments to Noncontrolling Interests Concentration Risk Type [Domain] Concentration Risk Type [Domain] Counterparty Name [Domain] Counterparty Name [Domain] Total StepStone Group Inc. stockholders’ equity Stockholders' Equity Attributable to Parent Forfeited (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Line of Credit Facility [Line Items] Line of Credit Facility [Line Items] Ownership [Domain] Ownership [Domain] Management contracts Management Contracts [Member] Management Contracts Entity Interactive Data Current Entity Interactive Data Current Carried interest allocation, focused commingled funds Carried Interest Allocation, Focused Commingled Funds [Member] Carried Interest Allocation, Focused Commingled Funds Less: Accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Incentive fees as percentage of profits Revenue From Contract With Customer, Incentive Fees As Percentage Of Net Investment Income Revenue From Contract With Customer, Incentive Fees As Percentage Of Net Investment Income Changes in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] FY2026 Finite-Lived Intangible Asset, Expected Amortization, Year Three Schedule of Changes in the Fair Value of Level III Financial Instruments Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Partnership StepStone Group LP [Member] StepStone Group LP Lease right-of-use assets, net Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Lease Right Of Use Assets, Net Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Lease Right Of Use Assets, Net Retained Earnings Retained Earnings [Member] Dividends declared Dividends, Common Stock, Cash Legacy carried interest allocation, focused comingled funds Legacy Carried Interest Allocation, Focused Commingled Funds [Member] Legacy Carried Interest Allocation, Focused Commingled Funds Total lease cost Lease, Cost Common Stock Common Stock [Member] Investment income of Consolidated Funds Unrealized investment income of Consolidated Funds Income (Loss) From Consolidated Funds Income (Loss) From Consolidated Funds Number of reportable segments Number of Reportable Segments Components of Lease Expense and Supplemental Cash Flow Information Lease, Cost [Table Text Block] Contingent consideration obligations Business Combination, Contingent Consideration, Liability Class of Stock [Axis] Class of Stock [Axis] Schedule of Unvested Restricted Stock Units Activity Schedule of Nonvested Restricted Stock Units Activity [Table Text Block] Income Taxes Income Tax, Policy [Policy Text Block] Revenues Revenue [Policy Text Block] Statement [Table] Statement [Table] Vested (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Class A common stock issued for Greenspring acquisition Stock Issued During Period, Value, Acquisitions Document Quarterly Report Document Quarterly Report Letters of credit Letter of Credit [Member] Liability classified awards Liability Classified Award [Member] Liability Classified Award Statistical Measurement [Axis] Statistical Measurement [Axis] Related Party Transaction [Axis] Related Party Transaction [Axis] Revenue from External Customers by Geographic Areas Revenue from External Customers by Geographic Areas [Table Text Block] Retained earnings Retained Earnings (Accumulated Deficit) Contractual rights: management contracts Contractual Rights, Management Contracts [Member] Contractual Rights, Management Contracts Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Separately Managed Account Concentration Risk Separately Managed Account Concentration Risk [Member] Separately Managed Account Concentration Risk Equity Components [Axis] Equity Components [Axis] Lease liabilities Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Lease Liabilities Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Lease Liabilities Contributions from redeemable non-controlling interests in Consolidated Funds Proceeds from Noncontrolling Interests Fair Value, Recurring Fair Value, Recurring [Member] Changes in operating assets and liabilities of Consolidated Funds: Adjustments To Reconcile Net Income (Loss) To Cash Provided By (Used In) Operating Activities, Consolidated Funds [Abstract] Adjustments To Reconcile Net Income (Loss) To Cash Provided By (Used In) Operating Activities, Consolidated Funds Related Party Transactions Related Party Transactions Disclosure [Text Block] Segments Segment Reporting, Policy [Policy Text Block] Accumulated Other Comprehensive Income Comprehensive Income, Policy [Policy Text Block] Pro Forma Effect Business Acquisition, Pro Forma Information [Table Text Block] Conversion basis Conversion Of Stock, Conversion Basis Conversion Of Stock, Conversion Basis Document Fiscal Year Focus Document Fiscal Year Focus Excluding Consolidated Funds Consolidated Entity, Excluding Consolidated VIE [Member] Focused commingled funds Management And Advisory Fees, Net, Focused Commingled Funds [Member] Management And Advisory Fees, Net, Focused Commingled Funds Cash flows from operating activities Net Cash Provided by (Used in) Operating Activities [Abstract] Less: Comprehensive income attributable to non-controlling interests Comprehensive Income (Loss), Net of Tax, Attributable to Nonredeemable Noncontrolling Interest Comprehensive Income (Loss), Net of Tax, Attributable to Nonredeemable Noncontrolling Interest Statement [Line Items] Statement [Line Items] Increase (Decrease) in Stockholders' Equity [Roll Forward] Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward] Unvested awards (in shares) Beginning balance (in shares) Ending balance (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number Legacy Funds Legacy Funds [Member] Legacy Funds Total other income (expense) Nonoperating Income (Expense) Variable Rate [Domain] Variable Rate [Domain] Intangible assets, gross Finite-Lived Intangible Assets, Gross Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Total Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Less Noncontrolling Interest Fair value adjustment for acquisition-related contingent consideration Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability Lease right-of-use assets, net Operating Lease, Right-of-Use Asset Accumulated Other Comprehensive Income Accumulated other comprehensive income AOCI Attributable to Parent [Member] Product Information [Line Items] Product Information [Line Items] Document Transition Report Document Transition Report Local Phone Number Local Phone Number Other assets and receivables Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Other Noncurrent Assets And Receivables Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Other Noncurrent Assets And Receivables Incremental income from assumed vesting and exchange of restricted share units and Class B units Dilutive Securities, Effect on Basic Earnings Per Share, Options and Restrictive Stock Units Changes in unrealized losses included in earnings related to financial liabilities still held at the reporting date Fair Value, Liability, Recurring Basis, Still Held, Unrealized Gain (Loss) Legacy Greenspring investments in funds Legacy Investments In Funds Legacy Investments In Funds SMAs Incentive Fees, Separately Managed Accounts [Member] Incentive Fees, Separately Managed Accounts Recent Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Cash and short-term receivables Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Current Assets, Cash And Receivables Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Current Assets, Cash And Receivables Weighted-average shares of Class A common stock: Weighted Average Number of Shares Outstanding Reconciliation [Abstract] Common stock, shares outstanding (in shares) Common stock, shares outstanding, beginning balance (in shares) Common stock, shares outstanding, ending balance (in shares) Common Stock, Shares, Outstanding Measurement Input, Option Volatility Measurement Input, Option Volatility [Member] Goodwill Goodwill Goodwill Total liabilities Liabilities, Fair Value Disclosure StepStone Funds Equity Method Investee [Member] Partnership And LLC Interests Partnership And LLC Interests [Member] Partnership And LLC Interests Adjustments to reconcile net income (loss) to net cash provided by operating activities of Consolidated Funds: Adjustments To Reconcile Net Income (Loss) To Net Cash Provided By Operating Activities Of Consolidated Funds [Abstract] Adjustments To Reconcile Net Income (Loss) To Net Cash Provided By Operating Activities Of Consolidated Funds Contributions Noncontrolling Interest, Increase from Subsidiary Equity Issuance Carried interest allocations: Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest [Abstract] Intangibles and Goodwill Goodwill and Intangible Assets Disclosure [Text Block] Income tax expense (benefit) Income Tax Expense (Benefit) Geographical [Domain] Geographical [Domain] Subsidiary or Equity Method Investee, Sale of Stock by Subsidiary or Equity Investee [Table] Subsidiary or Equity Method Investee, Sale of Stock by Subsidiary or Equity Investee [Table] Preferred stock, par value (in dollars per share) Preferred Stock, Par or Stated Value Per Share FY2027 Lessee, Operating Lease, Liability, to be Paid, Year Four Income Statement [Abstract] Additional Paid-in Capital Additional Paid-in Capital [Member] Document Fiscal Period Focus Document Fiscal Period Focus Exchange One Exchange One [Member] Exchange One Sterling Overnight Index Average Sterling Overnight Index Average [Member] Sterling Overnight Index Average Liability classified awards, settlement Share-Based Payment Arrangement, Cash Used to Settle Award Diluted (in shares) Weighted-average shares of Class A common stock outstanding - Diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Incentive fees Total incentive fees Incentive Fees [Member] Incentive Fees Investments, at fair value Investments Common stock Common Stock, Value, Issued Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Investments in funds Equity Method Investments, Excluding Accrued Carried Interest Allocations Equity Method Investments, Excluding Accrued Carried Interest Allocations Granted (in dollars 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 Net Realized Gains (Losses) on Investments Realized Investment Gains (Losses) Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Legacy Greenspring accrued carried interest-related compensation Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Legacy Carried Interest Related Compensation Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Legacy Carried Interest Related Compensation Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] Impairment of finite-lived intangible assets Impairment of Intangible Assets, Finite-Lived Performance fee-related compensation: Share-Based Payment Arrangement, Recognized Amount [Abstract] Variable Interest Entity [Line Items] Variable Interest Entity [Line Items] Cash, cash equivalents and restricted cash at beginning of period Cash, cash equivalents and restricted cash at end of period Total cash, cash equivalents and restricted cash Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents Foreign currency translation adjustment Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Less: Net income attributable to non-controlling interests Net Income (Loss) Attributable to Noncontrolling Interest Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Goodwill, impairment loss Goodwill, Impaired, Accumulated Impairment Loss Investment in fund, before eliminations Investment In Fund, Before Eliminations Investment In Fund, Before Eliminations Schedule of Equity Method Investments Equity Method Investments [Table Text Block] Remeasurement of lease liabilities Remeasurement Of Lease Liabilities Remeasurement Of Lease Liabilities Common stock, shares issued (in shares) Common Stock, Shares, Issued Additions Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Purchases Total equity method investments Equity Method Investments Partner Type [Axis] Partner Type [Axis] Acquisition-related costs Business Combination, Acquisition Related Costs Accrued dividends Dividends Incurred But Not Yet Paid Dividends Incurred But Not Yet Paid 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] Amendment Flag Amendment Flag Finite-lived intangible assets, estimated useful lives Finite-Lived Intangible Asset, Useful Life Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Operating lease cost Operating Lease, Cost Outstanding (in shares) Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other Than Options, Outstanding Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other Than Options, Outstanding Investment Type [Axis] Investment Type [Axis] Investments Investment, Policy [Policy Text Block] Total other comprehensive income (loss) Other comprehensive loss Other Comprehensive Income (Loss), Net of Tax Proceeds from revolving credit facility Proceeds from Long-Term Lines of Credit Comprehensive income (loss) attributable to StepStone Group Inc. Comprehensive Income (Loss), Net of Tax, Attributable to Parent Schedule of Fair Value of Liabilities Fair Value, Liabilities Measured on Recurring Basis [Table Text Block] Base interest rate Debt Instrument, Base Interest Rate Debt Instrument, Base Interest Rate Entity Current Reporting Status Entity Current Reporting Status Schedule of Earnings Per Share, Basic, by Common Class, Including Two Class Method [Table] Schedule of Earnings Per Share, Basic, by Common Class, Including Two Class Method [Table] Goodwill and Intangible Assets Disclosure [Abstract] Deferred income taxes Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Intangibles and Goodwill Goodwill and Intangible Assets, Policy [Policy Text Block] Accrued compensation and benefits Increase (Decrease) in Employee Related Liabilities Fund reimbursement revenues Management And Advisory Fees, Net, Fund Reimbursement Revenues [Member] Management And Advisory Fees, Net, Fund Reimbursement Revenues Depreciation and amortization Depreciation, Depletion and Amortization Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Dividends payable (in dollars per share) Dividends Payable, Amount Per Share Total performance fee-related compensation Performance Fee-Related Compensation Related to Carried Interest Allocation Performance Fee-Related Compensation Related to Carried Interest Allocation Counterparty Name [Axis] Counterparty Name [Axis] Schedule of Related Party Transactions Schedule of Related Party Transactions [Table Text Block] Due from affiliates Increase (Decrease) in Due from Related Parties Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Legacy Greenspring accrued carried interest allocations Legacy Accrued Carried Interest Allocations Legacy Accrued Carried Interest Allocations Accrued carried interest allocations Equity Method Investments, Accrued Carried Interest Allocations Equity Method Investments, Accrued Carried Interest Allocations Finite-lived intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles Total equity method income (loss) Revenue Not From Contract With Customer, Income Loss From Equity Method Investments And Investment Income Revenue Not From Contract With Customer, Income Loss From Equity Method Investments And Investment Income Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Two Investments Two Investments [Member] Two Investments Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Effect of foreign currency exchange rate changes Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Continuing Operations Operating cash flows used for operating leases Operating Lease, Payments Entities [Table] Entities [Table] Schedule of Future Amortization of 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of Comprehensive Income [Abstract] Equity reallocation between controlling and non-controlling interests Adjustments To Additional Paid In Capital, Reallocation Of Noncontrolling Interest Adjustments To Additional Paid In Capital, Reallocation Of Noncontrolling Interest Common Class B Member, Issuable In Connection With Vesting Of Class B2 Units Common Class B Member, Issuable In Connection With Vesting Of Class B2 Units [Member] Common Class B Member, Issuable In Connection With Vesting Of Class B2 Units Maximum Maximum [Member] Non-Controlling Interests Consolidation, Subsidiaries or Other Investments, Consolidated Entities, Policy [Policy Text Block] Accumulated other comprehensive income Accumulated Other Comprehensive Income (Loss), Net of Tax Class A Common Stock Class A common stock Common Class A [Member] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Restricted Cash Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block] Legacy Greenspring investments in funds and accrued carried interest allocations Legacy Investments In Funds And Accrued Carried Interest Allocations Legacy Investments In Funds And Accrued Carried Interest Allocations Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Accounting for Differing Fiscal Periods Fiscal Period, Policy [Policy Text Block] Accrued carried interest-related compensation Increase (Decrease) in Accrued Carried Interest-Related Compensation Payable Increase (Decrease) in Accrued Carried Interest-Related Compensation Payable Total investments Investment Of Consolidated Funds And Equity Method Investments Investment Of Consolidated Funds And Equity Method Investments Deferred revenue, revenue recognized Contract with Customer, Liability, Revenue Recognized Business Acquisition [Line Items] Business Acquisition [Line Items] Entity Small Business Entity Small Business Other Commitments [Table] Other Commitments [Table] Legacy gross carried interest allocation, focused comingled funds Legacy Gross Carried Interest Allocation, Focused Commingled Funds [Member] Legacy Gross Carried Interest Allocation, Focused Commingled Funds Measurement Frequency [Domain] Measurement Frequency [Domain] Stockholders' Equity and Redeemable Interests Stockholders' Equity Note Disclosure [Text Block] Dividend (in dollars per share) Common Stock, Dividends, Per Share, Declared Revenues Revenues [Abstract] Intangibles, net Finite-Lived Intangible Assets, Net Affiliated entities Investor [Member] Line of Credit Facility [Table] Line of Credit Facility [Table] Distributions Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders Restricted cash Restricted Cash Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Unrecognized non-cash compensation Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Sublease income Sublease Income Fees and accounts receivable Increase (Decrease) in Accounts Receivable Title of 12(b) Security Title of 12(b) Security Liability classified awards Liability Classified Awards, Fair Value Disclosure Liability Classified Awards, Fair Value Disclosure Organization Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Deferred tax effect resulting from transactions affecting ownership in the Partnership, including net amounts payable under Tax Receivable Agreements Deferred Tax Effect From Purchase Of Units, Net Deferred Tax Effect From Purchase Of Units, Net Consolidated Entities [Axis] Consolidated Entities [Axis] Total expenses Costs and Expenses Subsequent Event [Line Items] Subsequent Event [Line Items] Business Combination and Asset Acquisition [Abstract] Lease liabilities Total operating lease liabilities Operating Lease, Liability FY2025 Finite-Lived Intangible Asset, Expected Amortization, Year Two Economic interest Economic Ownership Interest Economic Ownership Interest Liabilities and stockholders’ equity Liabilities and Equity [Abstract] Consolidated Entities, Excluding Legacy Entities Consolidated Entities, Excluding Legacy Entities [Member] Consolidated Entities, Excluding Legacy Entities Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Denominator: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Contractual rights Contractual Rights [Member] Tax Receivable Agreements Tax Receivable Agreement, Policy [Policy Text Block] Tax Receivable Agreement, Policy Revenues Business Acquisition, Pro Forma Revenue And Unrealized Gains (Losses) Business Acquisition, Pro Forma Revenue And Unrealized Gains (Losses) Other assets and receivables Other assets and receivables Increase (Decrease) in Other Operating Assets Acquisition date fair value of consideration transferred: Business Combination, Consideration Transferred [Abstract] Schedule of Product Information [Table] Schedule of Product Information [Table] Amortization of deferred financing costs Write off of Deferred Debt Issuance Cost Cash flows from financing activities of Consolidated Funds: Adjustments To Reconcile Net Income (Loss) To Cash Provided By (Used In) Financing Activities [Abstract] Adjustments To Reconcile Net Income (Loss) To Cash Provided By (Used In) Financing Activities, Consolidated Funds Contributed capital Partners' Capital Account, Contributions Entity Filer Category Entity Filer Category Noncontrolling Interests In Consolidated Funds Redeemable Noncontrolling Interest [Table Text Block] Basic (in shares) Weighted-average shares of Class A common stock outstanding – Basic (in shares) Weighted Average Number of Shares Outstanding, Basic Stockholders’ equity: Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Focused commingled funds Incentive Fees, Focused Commingled Funds [Member] Incentive Fees, Focused Commingled Funds Schedule of Carrying Value of the Assets and Liabilities of the Company's Variable Interest Entities Schedule of Variable Interest Entities [Table Text Block] United States UNITED STATES Earnings since acquisition date Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual Consolidated Funds Consolidated Funds [Member] Consolidated Funds Equity-based compensation Liability based awards, expense Share-Based Payment Arrangement, Expense Non-cash operating, investing, and financing activities: Noncash Investing and Financing Items [Abstract] Commitments and contingencies (Note 15) Commitments and Contingencies Security Exchange Name Security Exchange Name Carried interest allocations Carried Interest Allocation [Member] Carried Interest Allocation Weighted-average amortization period Acquired Finite-Lived Intangible Assets, Weighted Average Useful Life Fees and accounts receivable Accounts Receivable, after Allowance for Credit Loss Class A common stock issued in exchange for Class B and Class C partnership units (in shares) Stockholders' Equity, Units Exchanged In Offering, Shares Stockholders' Equity, Units Exchanged In Offering, Shares Three Investments Three Investments [Member] Three Investments Redeemable non-controlling interests in Consolidated Funds Beginning balance Ending balance Redeemable Noncontrolling Interest, Equity, Carrying Amount Letters of credit outstanding Letters of Credit Outstanding, Amount Schedule of Debt Obligations Schedule of Debt [Table Text Block] Payments to related parties under Tax Receivable Agreements Payments to related parties under Tax Receivable Agreements Payments To Related Parties, Tax Receivable Agreements Payments To Related Parties, Tax Receivable Agreements Service fees Revenues Revenue from Contract with Customer, Excluding Assessed Tax Common stock and units Business Combination, Consideration Transferred, Equity Interests Issued and Issuable Cover [Abstract] Leases Lessee, Leases [Policy Text Block] Level III Fair Value, Inputs, Level 3 [Member] Equity-Based Compensation Share-Based Payment Arrangement [Text Block] Other assets and receivables Other Assets Revenues Revenue from Contract with Customer [Text Block] Noncontrolling Interest Noncontrolling Interest [Member] Investments [Domain] Investments [Domain] Payments for employee taxes related to net settlement of RSUs Payment, Tax Withholding, Share-Based Payment Arrangement Total liabilities and stockholders’ equity Liabilities and Equity Term Debt Instrument, Term Comingled Funds Concentration Risk Comingled Funds Concentration Risk [Member] Comingled Funds Concentration Risk Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Related Party [Axis] Related Party [Axis] Less: Net income attributable to redeemable non-controlling interests in Consolidated Funds Net income Net Income (Loss) Attributable to Redeemable Noncontrolling Interest Payments on revolving credit facility Repayments of Long-Term Lines of Credit Assumed vesting of RSUs and exchange of Class B2 units (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements Non-U.S. countries Non-US [Member] Membership ownership percentage Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest Organization, Consolidation and Presentation of Financial Statements [Abstract] Cash paid for Greenspring acquisition, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Non-controlling interests in legacy Greenspring entities Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value Level II Fair Value, Inputs, Level 2 [Member] Current Fiscal Year End Date Current Fiscal Year End Date Deferred tax effect resulting from transactions affecting ownership in the Partnership, net of amounts payable under Tax Receivable Agreements Adjustments To Additional Paid In Capital, Deferred Tax Effect Of Exchange Adjustments To Additional Paid In Capital, Deferred Tax Effect Of Exchange Less: Imputed interest Lessee, Operating Lease, Liability, Undiscounted Excess Amount Net income (loss) attributable to StepStone Group Inc. – Diluted Net Income (Loss) Available to Common Stockholders, Diluted Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Diluted (in dollars per share) Diluted (in dollars per share) Earnings Per Share, Diluted Intangibles, net Intangible Assets, Net (Excluding Goodwill) Sale of Stock [Domain] Sale of Stock [Domain] Vested (in shares) Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other Than Options, Vested Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other Than Options, Vested Vesting period Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period Payment of deferred offering costs Payments of Stock Issuance Costs Schedule of Rollforward of the Company's Shares of Common Stock Outstanding Since IPO Schedule of Stock by Class [Table Text Block] Equity-based compensation APIC, Share-Based Payment Arrangement, Increase for Cost Recognition Concentration Risk Type [Axis] Concentration Risk Type [Axis] FY2025 Lessee, Operating Lease, Liability, to be Paid, Year Two Net income (loss) Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest Unrecognized tax benefits Unrecognized Tax Benefits Class A common stock issued for vesting of RSUs, net of shares withheld for employee taxes (in shares) Stock Issued During Period, Shares, Restricted Stock Award, Net of Shares Withheld For Employee Taxes Stock Issued During Period, Value, Restricted Stock Award, Net of Shares Withheld For Employee Taxes Due from affiliates Due from Related Parties Other income (expense) Nonoperating Income (Expense) [Abstract] Schedule of Maturities of Operating Lease Liabilities Lessee, Operating Lease, Liability, Maturity [Table Text Block] Entity Address, Address Line Two Entity Address, Address Line Two Changes to uncertain tax positions Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit Entity Address, Address Line One Entity Address, Address Line One Spread on base commitment fee percentage if utilization less than 50% Line Of Credit Facility, Commitment Fee Percentage, Spread On Base If Utilization Less Than 50 Percent Line Of Credit Facility, Commitment Fee Percentage, Spread On Base If Utilization Less Than 50 Percent Other financing activities Proceeds from (Payments for) Other Financing Activities Deferred revenue Contract with Customer, Liability Class B2 units Class B2 Unit [Member] Class B2 Unit Net Unrealized Gains (Losses) on Investments Unrealized Gain (Loss) on Investments Lease right-of-use assets, net and lease liabilities Increase (Decrease) In Lease Right Of Use Assets, Net Of Lease Liabilities Increase (Decrease) In Lease Right Of Use Assets, Net Of Lease Liabilities Product and Service [Axis] Product and Service [Axis] Class of Stock [Domain] Class of Stock [Domain] Increase (decrease) in valuation allowance Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount Legacy Greenspring accrued carried interest-related compensation Legacy Investment, Accrued Carried Interest Related Compensation Payable Legacy Investment, Accrued Carried Interest Related Compensation Payable Fair Value Disclosures [Abstract] Subsidiary, Sale of Stock [Line Items] Subsidiary, Sale of Stock [Line Items] Interest expense Interest Expense Credit Facility [Axis] Credit Facility [Axis] Service agreements Service Agreements [Member] Reconciliation of cash, cash equivalents and restricted cash: Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents [Abstract] Variable Interest Entity, Not Primary Beneficiary, Legacy Entities Variable Interest Entity, Not Primary Beneficiary, Legacy Entities [Member] Variable Interest Entity, Not Primary Beneficiary, Legacy Entities Equity [Abstract] Subsequent Event [Table] Subsequent Event [Table] Vested (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period Estimated fair value of assets acquired and liabilities assumed: Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract] Entity Tax Identification Number Entity Tax Identification Number Schedule of Investments of Consolidated Funds Consolidated Funds Investments [Table Text Block] Consolidated Funds Investments Common stock, number of votes Common Stock, Number of Votes Common Stock, Number of Votes Reclassifications Reclassification, Comparability Adjustment [Policy Text Block] Schedule of Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] Revenue from Contract with Customer [Abstract] Remainder of FY2023 Finite-Lived Intangible Asset, Expected Amortization, Remainder of Fiscal Year Consolidated Entities [Domain] Consolidated Entities [Domain] Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Carried interest allocation as percentage of cumulative fund or account performance Revenue, Carried Interest Allocation As Percentage Of Cumulative Fund Or Account Performance Revenue, Carried Interest Allocation As Percentage Of Cumulative Fund Or Account Performance Net increase (decrease) in cash, cash equivalents and restricted cash Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Class Of Partnership Unit [Domain] Class Of Partnership Unit [Domain] Class Of Partnership Unit [Domain] Business combination, contingent consideration, liability, measurement input Business Combination, Contingent Consideration, Liability, Measurement Input Entity Central Index Key Entity Central Index Key Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Interest income Investment Income, Interest Measurement Frequency [Axis] Measurement Frequency [Axis] Weighted-Average Grant-Date Fair Value Per RSU Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Increase in due to related parties, tax receivable agreements Increase (Decrease) In Due To Related Parties, Tax Receivable Agreements Increase (Decrease) In Due To Related Parties, Tax Receivable Agreements Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Total purchase price Business Combination, Consideration Transferred Measurement Input Type [Axis] Measurement Input Type [Axis] Accounts payable, accrued expenses and other liabilities Increase (Decrease) in Other Accounts Payable and Accrued Liabilities Exchange Three Exchange Three [Member] Exchange Three City Area Code City Area Code General, administrative and other General and Administrative Expense Assets Assets [Abstract] Long-term Debt, Type [Domain] Long-Term Debt, Type [Domain] Other Commitments [Line Items] Other Commitments [Line Items] Sale of Stock [Axis] Sale of Stock [Axis] Cash flows from financing activities Net Cash Provided by (Used in) Financing Activities [Abstract] Current Events Current Events [Policy Text Block] Current Events Equity-based compensation Share-Based Payment Arrangement, Noncash Expense Contributions to investments Payments to Acquire Equity Method Investments Variable Rate [Axis] Variable Rate [Axis] Investments Equity Method Investments and Joint Ventures Disclosure [Text Block] Investment income (loss) Income (Loss) from Equity Method Investments Unfunded capital commitments Off-Balance-Sheet, Credit Loss, Liability Other liabilities and payables Increase (Decrease) in Other Operating Liabilities Purchases of property and equipment Payments to Acquire Property, Plant, and Equipment Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Carried interest allocation revenues, no economic interest Carried Interest Allocations, No Economic Interest [Member] Carried Interest Allocations, No Economic Interest FY2024 Finite-Lived Intangible Asset, Expected Amortization, Year One Spread on base commitment fee percentage if utilization greater than 50% Line Of Credit Facility, Commitment Fee Percentage, Spread On Base If Utilization Greater Than 50 Percent Line Of Credit Facility, Commitment Fee Percentage, Spread On Base If Utilization Greater Than 50 Percent Schedule of Reconciliations of Basic and Diluted Earnings Per Share of Class A Common Stock Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Interest rate in effect Line of Credit Facility, Interest Rate at Period End Establishment of lease liabilities in exchange for lease right-of-use assets Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Class A common stock issued for Greenspring acquisition Stock Issued For Acquisitions Stock Issued For Acquisitions