S 000059809 Summary1 [Member] Prospectus Summary Prospectus Summary S 000059809 [Member] Dreyfus Treasury and Agency Liquidity Money Market Fund Dreyfus Treasury and Agency Liquidity Money Market Fund C 000195671 [Member] Single Share Single Share cik0001717375_PrincipalRisksMember [Member] Principal Risks Principal Risks cik0001717375_InterestrateriskMember [Member] · Interest rate risk · Interest rate risk cik0001717375_LiquidityriskMember [Member] · Liquidity risk · Liquidity risk cik0001717375_MarketriskMember [Member] · Market risk · Market risk cik0001717375_USTreasurysecuritiesriskMember [Member] · U.S. Treasury securities risk · U.S. Treasury securities risk cik0001717375_RepurchaseagreementcounterpartyriskMember [Member] · Repurchase agreement counterparty risk · Repurchase agreement counterparty risk cik0001717375_ESGevaluationriskMember [Member] · ESG evaluation risk · ESG evaluation risk Document Type Document Type Document Period End Date Document Period End Date Entity Central Index Key Entity Central Index Key Amendment Flag Amendment Flag Document Creation Date Document Creation Date EntityInvCompanyType EntityInvCompanyType Registrant Name Registrant Name Document Effective Date Document Effective Date Prospectus Date Prospectus Date Risk/Return [Heading] Risk/Return [Heading] Objective [Heading] Objective [Heading] Objective, Primary [Text Block] Objective, Primary [Text Block] Objective, Secondary [Text Block] Objective, Secondary [Text Block] Expense [Heading] Expense [Heading] Expense Narrative [Text Block] Expense Narrative [Text Block] Expense Breakpoint Discounts [Text] Expense Breakpoint Discounts [Text] Expense Breakpoint, Minimum Investment Required [Amount] Expense Breakpoint, Minimum Investment Required [Amount] Operating Expenses Caption [Text] Operating Expenses Caption [Text] Expense Example [Heading] Expense Example [Heading] Expense Example Narrative [Text Block] Expense Example Narrative [Text Block] Expense Example, with Redemption, 1 Year 1 Year Expense Example, with Redemption, 3 Years 3 Years Expense Example, with Redemption, 5 Years 5 Years Expense Example, with Redemption, 10 Years 10 Years Strategy [Heading] Strategy [Heading] Strategy Narrative [Text Block] Strategy Narrative [Text Block] Strategy Portfolio Concentration [Text] Strategy Portfolio Concentration [Text] Risk [Heading] Risk [Heading] Risk [Text Block] Risk [Text Block] Bar Chart and Performance Table [Heading] Bar Chart and Performance Table [Heading] Performance Narrative [Text Block] Performance Narrative [Text Block] Performance Information Illustrates Variability of Returns [Text] Performance Information Illustrates Variability of Returns [Text] Performance Additional Market Index [Text] Performance Additional Market Index [Text] Bar Chart Does Not Reflect Sales Loads [Text] Bar Chart Does Not Reflect Sales Loads [Text] Performance Availability Website Address [Text] Performance Availability Website Address [Text] Performance Past Does Not Indicate Future [Text] Performance Past Does Not Indicate Future [Text] Performance Availability Phone [Text] Performance Availability Phone [Text] Performance One Year or Less [Text] Performance One Year or Less [Text] Performance Table One Class of after Tax Shown [Text] Performance Table One Class of after Tax Shown [Text] Performance Table Does Reflect Sales Loads Performance Table Does Reflect Sales Loads Performance Table Uses Highest Federal Rate Performance Table Uses Highest Federal Rate Performance Table Explanation after Tax Higher Performance Table Explanation after Tax Higher Performance Table Not Relevant to Tax Deferred Performance Table Not Relevant to Tax Deferred Bar Chart [Heading] Bar Chart [Heading] Annual Return 2018 Annual Return 2018 Annual Return 2019 Annual Return 2019 Annual Return 2020 Annual Return 2020 Annual Return 2021 Annual Return 2021 Annual Return 2022 Annual Return 2022 Annual Return 2023 Annual Return 2023 Annual Return 2024 Annual Return 2024 Bar Chart Closing [Text Block] Bar Chart Closing [Text Block] Highest Quarterly Return, Label Label Highest Quarterly Return, Date Highest Quarterly Return, Date Highest Quarterly Return Highest Quarterly Return Lowest Quarterly Return, Label Label Lowest Quarterly Return, Date Lowest Quarterly Return, Date Lowest Quarterly Return Lowest Quarterly Return Year to Date Return, Label Year to Date Return, Label Bar Chart, Year to Date Return, Date Bar Chart, Year to Date Return, Date Bar Chart, Year to Date Return Bar Chart, Year to Date Return Performance Table Market Index Changed Performance Table Market Index Changed Performance Table Closing [Text Block] Performance Table Closing [Text Block] Money Market Seven Day Yield, Caption [Text] Money Market Seven Day Yield, Caption [Text] Money Market Seven Day Yield Phone Money Market Seven Day Yield Phone Average Annual Return, Caption Average Annual Return, Caption 1 Year 1 Year 5 Years 5 Years Since Inception Since Inception Inception Date Inception Date Document [Axis] Document [Axis] Series [Axis] Series [Axis] Prospectus Prospectus Prospectus: Prospectus: Risk/Return: Risk/Return: Shareholder Fees [Table] Shareholder Fees [Table] Annual Fund Operating Expenses [Table] Annual Fund Operating Expenses [Table] Expense Example, With Redemption [Table] Expense Example, With Redemption [Table] Expense Example, No Redemption [Table] Expense Example, No Redemption [Table] Bar Chart [Table] Bar Chart [Table] Performance [Table] Performance [Table] Market Index Performance [Table] Market Index Performance [Table] Performance Measure [Axis] Performance Measure [Axis] Share Class [Axis] Share Class [Axis] Before Taxes Before Taxes After Taxes on Distributions After Taxes on Distributions After Taxes on Distributions and Sales After Taxes on Distributions and Sales Risk [Axis] Risk [Axis] All Risks [Member] All Risks [Member] Risk Lose Money [Member] Risk Lose Money [Member] Risk Not Insured [Member] Risk Not Insured [Member] Risk Nondiversified Status [Member] Risk Nondiversified Status [Member] Risk Not Insured Depository Institution [Member] Risk Not Insured Depository Institution [Member] Risk Money Market Fund Price Fluctuates [Member] Risk Money Market Fund Price Fluctuates [Member] Risk Money Market Fund May Impose Fees or Suspend Sales [Member] Risk Money Market Fund May Impose Fees or Suspend Sales [Member] Risk Money Market Fund Sponsor May Not Provide Support [Member] Risk Money Market Fund Sponsor May Not Provide Support [Member] Risk Money Market Fund May Not Preserve Dollar [Member] Risk Money Market Fund May Not Preserve Dollar [Member] Management fees Other expenses Total annual fund operating expenses Risks [Table Text Block] Risks [Table Text Block]