Label	Element	Value
Institutional Shares Prospectus \| DREYFUS TAX EXEMPT CASH MANAGEMENT FUND
Risk/Return:	rr_RiskReturnAbstract
Supplement to Prospectus [Text Block]	rr_SupplementToProspectusTextBlock	February 1, 2022 DREYFUS TAX EXEMPT CASH MANAGEMENT FUNDS Dreyfus Tax Exempt Cash Management Institutional Shares Supplement to Current Summary Prospectus and Prospectus
Risk/Return [Heading]	rr_RiskReturnHeading	Dreyfus Tax Exempt Cash Management
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	The following information supplements the information below the table in "Fees and Expenses" in the fund's summary prospectus and "Fund Summary – Fees and Expenses" in the fund's prospectus: The fund's investment adviser, BNY Mellon Investment Adviser, Inc., has contractually agreed, until at least May 31, 2023, to waive receipt of its fees and/or assume the direct expenses of the fund's Institutional shares so that the direct expenses of the fund's Institutional shares (excluding taxes, interest, portfolio transaction costs, commitment fees on borrowing and extraordinary expenses) do not exceed .20%. On or after May 31, 2023, BNY Mellon Investment Adviser, Inc. may terminate the expense limitation agreement at any time.
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	May 31, 2023

This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $[ ] in [name of fund family] funds. More information about these and other discounts is available from your financial intermediary and in [identify section heading and page number] of the Fund's prospectus and [identify section heading and page number] of the Fund's statement of additional information

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Subsection instructions
-Paragraph 1
-Subparagraph b

+ Details

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- Definition

This element represents the date of expected termination of any expense reimbursement or fee waiver arrangements that reduce any Fund operating expenses (SEC Form N-1A 2006-09-14 A.3.table.1.11 Total Annual Fund Operating Expenses A.3.instructions.3.e).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Subsection instructions
-Paragraph 3
-Subparagraph e

+ Details

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- References

No definition available.

+ Details

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- Definition

Risk/Return Summary Investment Objectives/Goals Include the following information, in plain English under rule 421(d) under the Securities Act, in the order and subject matter indicated

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 2

+ Details

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- Definition

This element contains the text of a prospectus supplement (submission type 497) not already contained in an element containing amended text or other data from a previous submission.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A

+ Details

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