Label	Element	Value
Dreyfus Government Cash Management
Risk/Return:	rr_RiskReturnAbstract
Supplement [Text Block]	ck0000740766_SupplementTextBlock	December 13, 2013 Dreyfus Government Cash Management Funds - Dreyfus Government Cash Management Supplement to Prospectuses dated June 1, 2013 *The following changes will take effect as of January 13, 2014*
Risk/Return [Heading]	rr_RiskReturnHeading	Dreyfus Government Cash Management
Strategy [Heading]	rr_StrategyHeading	The following replaces the second sentence in "Fund Summary - Dreyfus Government Cash Management - Principal Investment Strategy":
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	To pursue its goal, the fund invests in securities issued or guaranteed as to principal and interest by the U.S. government or its agencies or instrumentalities, including those with floating or variable rates of interest, and repurchase agreements (including tri-party repurchase agreements).

No authoritative reference available.

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

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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

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- Definition

+ 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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