Label	Element	Value
DREYFUS BASIC MONEY MARKET FUND, INC
Risk/Return:	rr_RiskReturnAbstract
Supplement to Prospectus [Text Block]	rr_SupplementToProspectusTextBlock	November 18, 2020 DREYFUS BASIC MONEY MARKET FUND, INC. Supplement to Summary Prospectus, Prospectus and Statement of Additional Information ("SAI") The following information supplements and supersedes and replaces any contrary information contained in the fund's Prospectus and SAI: Effective on or about February 1, 2021, the management agreement between Dreyfus BASIC Money Market Fund, Inc. and BNY Mellon Investment Adviser, Inc. will be amended to reflect a reduction in the management fee payable by the fund to BNY Mellon Investment Adviser, Inc. from an annual rate of 0.50% to an annual rate of 0.20% of the value of the fund's average daily net assets.
Risk/Return [Heading]	rr_RiskReturnHeading	DREYFUS BASIC MONEY MARKET FUND, INC

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

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

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