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value Share-Based Compensation Arrangement by Share-Based Payment Award, Maximum Number of Shares Per Employee, Value Share-Based Compensation Arrangement by Share-Based Payment Award, Maximum Number of Shares Per Employee, Value Interest expense Interest Expense, Nonoperating Forward foreign currency contracts Partnership And LLC Interests [Member] Partnership And LLC Interests Adjustments to reconcile net loss to net cash used in 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 Equity-Based Compensation Share-Based Payment Arrangement [Text Block] Accounts payable, accrued expenses and other liabilities Accounts Payable and Other Accrued Liabilities Related party, beneficial owner, minimum percentage Related Party, Beneficial Owner, Minimum Percentage Related 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Vesting Date of Prior Year Equity Awards Vested in Covered Year [Member] Dividend (in dollars per share) Common Stock, Dividends, Per Share, Declared Legacy accrued carried interest allocations Legacy Accrued Carried Interest Allocations Legacy Accrued Carried Interest Allocations Entity File Number Entity File Number Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Accrued carried interest allocations Equity Method Investments, Accrued Carried Interest Allocations Equity Method Investments, Accrued Carried Interest Allocations Equity securities Equity Securities [Member] Total equity method income 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 Distributions Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders Portion of equity interests expected to be acquired, 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Variable Interest Entities [Table Text Block] Entity Information [Line Items] Entity Information [Line Items] Accrued carried interest-related compensation Equity Method Investment, Accrued Carried Interest Related Compensation Payable Equity Method Investment, Accrued Carried Interest Related Compensation Payable Equity Components [Axis] Equity Components [Axis] Fees and accounts receivable Increase (Decrease) in Accounts Receivable Performance fee-related compensation: Share-Based Payment Arrangement, Recognized Amount [Abstract] Product and Service [Domain] Product and Service [Domain] Cash-based compensation, expense Deferred Compensation Arrangement with Individual, Compensation Expense Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Class A Common Stock Common Class A [Member] Entity Interactive Data Current Entity Interactive Data Current Variable Rate [Axis] Variable Rate [Axis] Less: Net income (loss) attributable to non-controlling interests Net Income (Loss) Attributable to Noncontrolling Interest Variable Interest Entity [Line Items] Variable Interest Entity [Line Items] Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] 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 Changes in unrealized gains (losses) included in earnings related to financial liabilities still held at the reporting date Fair Value, Liability, Recurring Basis, Still Held, Unrealized Gain (Loss) Entity Small Business Entity Small Business Comprehensive loss attributable to StepStone Group Inc. Comprehensive Income (Loss), Net of Tax, Attributable to Parent Limited Partners Limited Partners [Member] Limited Partners FY2030 Lessee, Operating Lease, Liability, to be Paid, Year Three Termination Date Trading Arrangement Termination Date 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 Subsequent Events [Abstract] Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] Document Type Document Type Changes in assets fair value hierarchy levels Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net 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] 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 Fair Value as of Grant Date Award Grant Date Fair Value Redemption price, percentage Debt Instrument, Redemption Price, Percentage Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Exchange of Partnership Units for Common Stock Exchange Of Partnership Units For Common Stock [Member] Exchange Of Partnership Units For Common Stock Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Share repurchase program, remaining authorized, amount Share Repurchase Program, Remaining Authorized, Amount Arrangement Duration Trading Arrangement Duration Subsequent Event [Line Items] Subsequent Event [Line Items] Local Phone Number Local Phone Number Entity Address, Postal Zip Code Entity Address, Postal Zip Code Entity Registrant Name Entity Registrant Name Loss before income tax Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Commitments and contingencies (Note 14) Commitments and Contingencies Intangible assets, gross Intangible Asset, Finite-Lived, before Accumulated Amortization Total revenues Revenues Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] FY2031 Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Four 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 Investment income Income (Loss) from Equity Method Investments Accounting Standards Update and Change in Accounting Principle [Table] Accounting Standards Update and Change in Accounting Principle [Table] Increase (Decrease) in Stockholders' Equity [Roll Forward] Equity, Attributable to Noncontrolling Interest [Roll Forward] Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Non-Controlling Interests Consolidation, Subsidiaries or Other Investments, Consolidated Entities, Policy [Policy Text Block] Executive Category: Executive Category [Axis] Schedule of Change in Unvested Restricted Stock Units and Performance-Based Restricted Stock Units Schedule of Nonvested Restricted Stock Units Activity [Table Text Block] Counterparty Name [Axis] Counterparty Name [Axis] Liabilities and stockholders’ equity Liabilities and Equity [Abstract] Other 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[Member] Consolidated Entities, Excluding Legacy Entities Geographical [Axis] Geographical [Axis] Restricted cash Restricted Cash Deferred revenue Contract with Customer, Liability Purchase of non-controlling interests Noncontrolling Interest, Increase From Redemptions or Purchase of Interests, Including True-Up Adjustment Noncontrolling Interest, Increase From Redemptions or Purchase of Interests, Including True-Up Adjustment Assets measured at net asset value Fair Value Measured at Net Asset Value Per Share [Member] Tax Receivable Agreements Tax Receivable Agreement, Policy [Policy Text Block] Tax Receivable Agreement, Policy Other assets and receivables Other Assets Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] Due from affiliates Increase (Decrease) in Due from Related Parties Entity Tax Identification Number Entity Tax Identification Number Other Commitments [Line Items] Other Commitments [Line Items] Revenues Revenue [Policy Text Block] 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 Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Schedule of Finite-Lived Intangible Assets [Table] Intangible Asset, Finite-Lived [Table] 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 Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Focused commingled funds Incentive Fees, Focused Commingled Funds [Member] Incentive Fees, Focused Commingled Funds Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] Borrowings Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Purchases Consolidated Funds Consolidated Funds [Member] Consolidated Funds Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Non-NEOs Non-NEOs [Member] Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member] Organization Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Comprehensive loss before non-controlling interests Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Debt Instrument [Axis] Debt Instrument [Axis] Subsequent Event [Table] Subsequent Event [Table] Equity-based compensation Share-Based Payment Arrangement, Noncash Expense FY2029 Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Two Total lease cost Lease, Cost Class A common stock issued for purchase of 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Series A 5.52% Notes Investment, Name [Domain] Investment, Name [Domain] Long-term Debt, Type [Domain] Long-Term Debt, Type [Domain] Basic (in dollars per share) Basic (in dollars per share) Earnings Per Share, Basic 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 Payments for repurchases of Class A common stock Payments for Repurchase of Common Stock Statistical Measurement [Axis] Statistical Measurement [Axis] Due to affiliates Increase (Decrease) in Due to Related Parties Insider Trading Arrangements [Line Items] Award Type [Axis] Award Type [Axis] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Class B common stock purchased at par value in connection with vesting of Class B2 units (in shares) Stockholders' Equity, Stock Purchased At Par Value In Connection With Vesting of Class B2 Units Stockholders' Equity, Stock Purchased At Par Value In Connection With Vesting of Class B2 Units Accumulated deficit Retained Earnings (Accumulated Deficit) Purchase period Share-Based Compensation Arrangement By Share-based Payment Award, Purchase Period Share-Based Compensation Arrangement By Share-based Payment Award, Purchase Period Product and Service [Axis] Product and Service [Axis] Thomas Keck [Member] Thomas Keck Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table [Member] Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Common Stock Common Stock [Member] Operating lease cost Operating Lease, Cost Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Cover [Abstract] Non-U.S. countries Non-US [Member] Comingled Funds Concentration Risk Comingled Funds Concentration Risk [Member] Comingled Funds Concentration Risk Equity method investment, total accrued carried interest allocation percentage Concentration Risk, Percentage Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Equity Awards Adjustments Equity Awards Adjustments [Member] Total liabilities and stockholders’ equity Liabilities and Equity Variable lease cost Variable Lease, Cost Deferred tax effect resulting from transactions affecting ownership in the Partnership Adjustments To Additional Paid In Capital, Deferred Tax Effect Of Exchange Adjustments To Additional Paid In Capital, Deferred Tax Effect Of Exchange Net realized gains on investments Realized Investment Gains (Losses) Employee Stock Option Share-Based Payment Arrangement, Option [Member] Purchases Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases Non-controlling interests Less: Amounts attributable to non-controlling interests Equity, Attributable to Noncontrolling Interest Other liabilities and payables Increase (Decrease) in Other Operating Liabilities Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Asset Class [Axis] Asset Class [Axis] Related Party [Domain] Related and Nonrelated Parties [Domain] Tabular List, Table Tabular List [Table Text Block] Additional paid-in capital Additional Paid in Capital Other income (loss) Other Nonoperating Income (Expense) FY2030 Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Three Remainder of FY2027 Intangible Asset, Finite-Lived, Estimated Amortization Expense, Remainder of Fiscal Year Name Awards Close in Time to MNPI Disclosures, Individual Name Stockholders’ equity: Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Forfeited (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period Schedule of Redeemable Non-Controlling Interests Redeemable Noncontrolling Interest [Table Text Block] General, administrative and other General and Administrative Expense Exchange of Class B, Class C and Class D units for Class A common stock and redemption of corresponding Class B common stock Stock Issued During Period, Value, Conversion of Convertible Securities Partnerships and LLC Interests Partnerships and LLC Interests [Member] Partnerships and LLC Interests Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Adjustment to Compensation: Adjustment to Compensation [Axis] Accounts payable, accrued expenses and other liabilities Increase (Decrease) in Other Accounts Payable and Accrued Liabilities 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 Less: Net income attributable to redeemable non-controlling interests Net income Net Income (Loss) Attributable to Redeemable Noncontrolling Interest Class of Stock [Domain] Class of Stock [Domain] Class B2 units Class B2 Unit [Member] Class B2 Unit 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 Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Statement of Cash Flows [Abstract] Purchase of non-controlling interests Redemption of redeemable non-controlling interests Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests Legacy Greenspring accrued carried interest-related compensation Legacy Investment, Accrued Carried Interest Related Compensation Payable Legacy Investment, Accrued Carried Interest Related Compensation Payable Schedule of Rollforward of the Company's Shares of Common Stock Outstanding Schedule of Stock by Class [Table Text Block] Credit Facility [Axis] Credit Facility [Axis] Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Total assets measured at fair value Assets, Fair Value Disclosure Investments Investment, Policy [Policy Text Block] Name Measure Name Income Taxes Income Tax Disclosure [Text Block] Pay vs Performance Disclosure [Line Items] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] 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 Number of annual exchanges Transaction Agreement, Number of Annual Exchanges Transaction Agreement, Number of Annual Exchanges Debt Instrument [Line Items] Debt Instrument [Line Items] Changes to uncertain tax positions Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Transaction agreement, exchange ratio Transaction Agreement, Exchange Ratio Transaction Agreement, Exchange Ratio 1 Month Term Secured Overnight Financing Rate (SOFR) 1 Month Term Secured Overnight Financing Rate (SOFR) [Member] 1 Month Term Secured Overnight Financing Rate (SOFR) Schedule of Investments of Consolidated Funds Consolidated Funds Investments [Table Text Block] Consolidated Funds Investments Additional Paid-in Capital Additional Paid-in Capital [Member] Entity Filer Category Entity Filer Category Performance-Based Restricted Stock Units Performance-Based Restricted Stock Units [Member] Performance-Based Restricted Stock Units Number of commingled funds greater than or equal to 10% of incentive fees Commingled Funds, Greater Than Or Equal To 10% Of Incentive Fees Commingled Funds, Greater Than Or Equal To 10% Of Incentive Fees Common stock, number of votes Common Stock, Number of Votes Common Stock, Number of Votes Dividends [Axis] Dividends [Axis] Total carried interest allocations Revenue Not from Contract with Customer Name Trading Arrangement, Individual Name Cash and cash equivalents Cash and Cash Equivalent General Partner General Partner [Member] Compensation and Benefits Compensation Related Costs, Policy [Policy Text Block] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Company Selected Measure Amount Company Selected Measure Amount 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 Class Of Partnership Unit [Domain] Class Of Partnership Unit [Domain] Class Of Partnership Unit [Domain] Equity Method Investments and Joint Ventures [Abstract] Depreciation and amortization Depreciation, Depletion and Amortization Changes in unrealized gains (losses) included in earnings related to financial assets still held at the reporting date Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss) Secured Overnight Financing Rate (SOFR) Secured Overnight Financing Rate (SOFR) [Member] Entity Address, Address Line Two Entity Address, Address Line Two SPD SPD [Member] SPD Facility D Facility D [Member] Facility D Net loss Net loss Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Statement of Partners' Capital [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 Weighted-average remaining lease term for operating leases (in years) Operating Lease, Weighted Average Remaining Lease Term Prime Rate Prime Rate [Member] Non-PEO NEO Non-PEO NEO [Member] Senior Secured Notes Senior Notes Senior Notes [Member] Entity Address, Address Line One Entity Address, Address Line One Impairment of finite-lived intangible assets Intangible Asset, Finite-Lived, Impairment Loss Establishment of lease liabilities in exchange for lease right-of-use assets Right-of-Use Asset Obtained in Exchange for Operating Lease Liability 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 Subsidiary, Sale of Stock [Line Items] Subsidiary, Sale of Stock [Line Items] Income tax benefit Income Tax Expense (Benefit) Exchange Three Exchange Three [Member] Exchange Three Accumulated Other Comprehensive Income Comprehensive Income, Policy [Policy Text Block] Adjustments to reconcile net loss to net cash provided by (used in) operating activities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Noncash Item [Abstract] Net income (loss) Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest Award Timing Method Award Timing Method [Text Block] Consolidation Consolidation, Policy [Policy Text Block] Net decrease in cash, cash equivalents and restricted cash Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Consolidated funds Variable Interest Entity, Primary Beneficiary [Member] Net loss attributable to StepStone Group Inc. Net loss attributable to StepStone Group Inc. – Basic Net Income (Loss) Attributable to Parent Performance Restricted Stock Units Performance Restricted Stock Units [Member] Performance Restricted Stock Units Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Statement [Table] Statement [Table] Current Events Current Events [Policy Text Block] Current Events Restatement Determination Date: Restatement Determination Date [Axis] Schedule of Components of Accumulated Other Comprehensive Income Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Interest income Investment Income, Interest Increase in deferred tax assets, exchange of partnership units for common stock Increase (Decrease) In Deferred Tax Assets, Exchange Of Partnership Units For Common Stock Increase (Decrease) In Deferred Tax Assets, Exchange Of Partnership Units For Common Stock Issuance of notes payable Proceeds from Notes Payable Leases Lessee, Leases [Policy Text Block] Fed Funds Effective Rate Overnight Index Swap Rate Fed Funds Effective Rate Overnight Index Swap Rate [Member] 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 impact on effective tax rate for equity-based compensation expense Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-Based Payment Arrangement, Amount Revenues Revenues [Abstract] Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] Numerator: Net Income (Loss) Available to Common Stockholders, Diluted [Abstract]