Document and Entity Information	Total
Prospectus:
Document Type	485BPOS
Document Period End Date	Jan. 31, 2022
Entity Registrant Name	Dreyfus Tax Exempt Cash Management Funds
Entity Central Index Key	0000740123
Entity Inv Company Type	N-1A
Amendment Flag	false
Document Creation Date	May 25, 2022
Document Effective Date	Jun. 01, 2022
Prospectus Date	Jun. 01, 2022
Institutional Shares Prospectus \| DREYFUS CASH MANAGEMENT \| Institutional Shares
Prospectus:
Trading Symbol	DICXX
Institutional Shares Prospectus \| Dreyfus Government Securities Cash Management \| Dreyfus Government Securities Cash Management - Institutional Shares
Prospectus:
Trading Symbol	DIPXX
Institutional Shares Prospectus \| Dreyfus Treasury Obligations Cash Management \| Institutional Shares
Prospectus:
Trading Symbol	DTRXX
Institutional Shares Prospectus \| DREYFUS TREASURY SECURITIES CASH MANAGEMENT \| Institutional Shares
Prospectus:
Trading Symbol	DIRXX
Institutional Shares Prospectus \| DREYFUS TAX EXEMPT CASH MANAGEMENT FUND \| DREYFUS TAX EXEMPT CASH MANAGEMENT - Institutional Shares
Prospectus:
Trading Symbol	DEIXX
Institutional Shares \| Dreyfus Government Cash Management \| dreyfus government cash mangement - Institutional Shares
Prospectus:
Trading Symbol	DGCXX

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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