Label	Element	Value
BNY Mellon Asset Allocation Fund
Risk/Return:	rr_RiskReturnAbstract
Supplement to Prospectus [Text Block]	rr_SupplementToProspectusTextBlock	December 9, 2020 BNY MELLON FUNDS TRUST BNY Mellon Asset Allocation Fund Supplement to Current Prospectus
Risk/Return [Heading]	rr_RiskReturnHeading	BNY Mellon Asset Allocation Fund
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The following information supplements the information contained in the sections of the fund's prospectus entitled "Fund Summary – BNY Mellon Asset Allocation Fund – Principal Investment Strategy" and "Fund Details – BNY Mellon Asset Allocation Fund": The Trust's board has approved the addition of an unaffiliated underlying fund as an investment option within the Investment Grade Bonds asset class of BNY Mellon Asset Allocation Fund.

No definition available.

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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

Principal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Subsection a

+ 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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