{
 "version": "2.2",
 "instance": {
  "rnlx-20231031.htm": {
   "nsprefix": "rnlx",
   "nsuri": "http://www.renalytixalplc.com/20231031",
   "dts": {
    "inline": {
     "local": [
      "rnlx-20231031.htm"
     ]
    },
    "schema": {
     "local": [
      "rnlx-20231031.xsd"
     ],
     "remote": [
      "http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd",
      "http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd",
      "http://www.xbrl.org/2003/xl-2003-12-31.xsd",
      "http://www.xbrl.org/2003/xlink-2003-12-31.xsd",
      "http://www.xbrl.org/2005/xbrldt-2005.xsd",
      "http://www.xbrl.org/2006/ref-2006-02-27.xsd",
      "https://www.xbrl.org/2020/extensible-enumerations-2.0.xsd",
      "https://www.xbrl.org/dtr/type/2020-01-21/types.xsd",
      "https://www.xbrl.org/dtr/type/2022-03-31/types.xsd",
      "https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd",
      "https://xbrl.fasb.org/srt/2023/elts/srt-roles-2023.xsd",
      "https://xbrl.fasb.org/srt/2023/elts/srt-types-2023.xsd",
      "https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd",
      "https://xbrl.fasb.org/us-gaap/2023/elts/us-roles-2023.xsd",
      "https://xbrl.fasb.org/us-gaap/2023/elts/us-types-2023.xsd",
      "https://xbrl.sec.gov/country/2023/country-2023.xsd",
      "https://xbrl.sec.gov/dei/2023/dei-2023.xsd"
     ]
    },
    "definitionLink": {
     "local": [
      "rnlx-20231031_def.xml"
     ]
    },
    "labelLink": {
     "local": [
      "rnlx-20231031_lab.xml"
     ]
    },
    "presentationLink": {
     "local": [
      "rnlx-20231031_pre.xml"
     ]
    }
   },
   "keyStandard": 25,
   "keyCustom": 0,
   "axisStandard": 1,
   "axisCustom": 0,
   "memberStandard": 0,
   "memberCustom": 1,
   "hidden": {
    "total": 6,
    "http://xbrl.sec.gov/dei/2023": 6
   },
   "contextCount": 2,
   "entityCount": 1,
   "segmentCount": 1,
   "elementCount": 31,
   "unitCount": 0,
   "baseTaxonomies": {
    "http://xbrl.sec.gov/dei/2023": 27
   },
   "report": {
    "R1": {
     "role": "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation",
     "longName": "100000 - Document - Document And Entity Information",
     "shortName": "Document And Entity Information",
     "isDefault": "true",
     "groupType": "document",
     "subGroupType": "",
     "menuCat": "Cover",
     "order": "1",
     "firstAnchor": {
      "contextRef": "C_0eb63d96-7166-471f-987e-ef891c42ed5d",
      "name": "dei:DocumentType",
      "unitRef": null,
      "xsiNil": "false",
      "lang": "en-US",
      "decimals": null,
      "ancestors": [
       "span",
       "p",
       "body",
       "html"
      ],
      "reportCount": 1,
      "baseRef": "rnlx-20231031.htm",
      "first": true,
      "unique": true
     },
     "uniqueAnchor": {
      "contextRef": "C_0eb63d96-7166-471f-987e-ef891c42ed5d",
      "name": "dei:DocumentType",
      "unitRef": null,
      "xsiNil": "false",
      "lang": "en-US",
      "decimals": null,
      "ancestors": [
       "span",
       "p",
       "body",
       "html"
      ],
      "reportCount": 1,
      "baseRef": "rnlx-20231031.htm",
      "first": true,
      "unique": true
     }
    }
   },
   "tag": {
    "dei_AmendmentFlag": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "AmendmentFlag",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Amendment Flag",
        "documentation": "Boolean flag that is true when the XBRL content amends previously-filed or accepted submission."
       }
      }
     },
     "auth_ref": []
    },
    "dei_DocumentInformationTable": {
     "xbrltype": "stringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "DocumentInformationTable",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Document Information [Table]",
        "documentation": "Container to support the formal attachment of each official or unofficial, public or private document as part of a submission package."
       }
      }
     },
     "auth_ref": []
    },
    "dei_Security12bTitle": {
     "xbrltype": "securityTitleItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "Security12bTitle",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Title of 12(b) Security",
        "documentation": "Title of a 12(b) registered security."
       }
      }
     },
     "auth_ref": [
      "r0"
     ]
    },
    "dei_DocumentType": {
     "xbrltype": "submissionTypeItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "DocumentType",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Document Type",
        "documentation": "The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'."
       }
      }
     },
     "auth_ref": []
    },
    "rnlx_AmericanDepositarySharesMember": {
     "xbrltype": "domainItemType",
     "nsuri": "http://www.renalytixalplc.com/20231031",
     "localname": "AmericanDepositarySharesMember",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "American Depositary Shares [Member]",
        "documentation": "American Depositary Shares."
       }
      }
     },
     "auth_ref": []
    },
    "dei_EntityAddressCountry": {
     "xbrltype": "countryCodeItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "EntityAddressCountry",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Address, Country",
        "documentation": "ISO 3166-1 alpha-2 country code."
       }
      }
     },
     "auth_ref": []
    },
    "dei_LocalPhoneNumber": {
     "xbrltype": "normalizedStringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "LocalPhoneNumber",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Local Phone Number",
        "documentation": "Local phone number for entity."
       }
      }
     },
     "auth_ref": []
    },
    "dei_EntityRegistrantName": {
     "xbrltype": "normalizedStringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "EntityRegistrantName",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Registrant Name",
        "documentation": "The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC."
       }
      }
     },
     "auth_ref": [
      "r1"
     ]
    },
    "dei_EntityEmergingGrowthCompany": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "EntityEmergingGrowthCompany",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Emerging Growth Company",
        "documentation": "Indicate if registrant meets the emerging growth company criteria."
       }
      }
     },
     "auth_ref": [
      "r1"
     ]
    },
    "dei_DocumentPeriodEndDate": {
     "xbrltype": "dateItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "DocumentPeriodEndDate",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Document Period End Date",
        "documentation": "For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period.  The format of the date is YYYY-MM-DD."
       }
      }
     },
     "auth_ref": []
    },
    "dei_EntityDomain": {
     "xbrltype": "domainItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "EntityDomain",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity [Domain]",
        "documentation": "All the names of the entities being reported upon in a document. Any legal structure used to conduct activities or to hold assets. Some examples of such structures are corporations, partnerships, limited liability companies, grantor trusts, and other trusts. This item does not include business and geographical segments which are included in the geographical or business segments domains."
       }
      }
     },
     "auth_ref": []
    },
    "dei_EntityIncorporationStateCountryCode": {
     "xbrltype": "edgarStateCountryItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "EntityIncorporationStateCountryCode",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Incorporation, State or Country Code",
        "documentation": "Two-character EDGAR code representing the state or country of incorporation."
       }
      }
     },
     "auth_ref": []
    },
    "dei_EntityAddressAddressLine2": {
     "xbrltype": "normalizedStringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "EntityAddressAddressLine2",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Address, Address Line Two",
        "documentation": "Address Line 2 such as Street or Suite number"
       }
      }
     },
     "auth_ref": []
    },
    "dei_DocumentInformationLineItems": {
     "xbrltype": "stringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "DocumentInformationLineItems",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Document Information [Line Items]",
        "documentation": "Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table."
       }
      }
     },
     "auth_ref": []
    },
    "dei_EntityAddressCityOrTown": {
     "xbrltype": "normalizedStringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "EntityAddressCityOrTown",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Address, City or Town",
        "documentation": "Name of the City or Town"
       }
      }
     },
     "auth_ref": []
    },
    "dei_EntityFileNumber": {
     "xbrltype": "fileNumberItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "EntityFileNumber",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Securities Act File Number",
        "documentation": "Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen."
       }
      }
     },
     "auth_ref": []
    },
    "dei_EntityTaxIdentificationNumber": {
     "xbrltype": "employerIdItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "EntityTaxIdentificationNumber",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Tax Identification Number",
        "documentation": "The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS."
       }
      }
     },
     "auth_ref": [
      "r1"
     ]
    },
    "dei_LegalEntityAxis": {
     "xbrltype": "stringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "LegalEntityAxis",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Legal Entity [Axis]",
        "documentation": "The set of legal entities associated with a report."
       }
      }
     },
     "auth_ref": []
    },
    "dei_PreCommencementTenderOffer": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "PreCommencementTenderOffer",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Pre-commencement Tender Offer",
        "documentation": "Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act."
       }
      }
     },
     "auth_ref": [
      "r4"
     ]
    },
    "dei_EntityAddressPostalZipCode": {
     "xbrltype": "normalizedStringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "EntityAddressPostalZipCode",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Address, Postal Zip Code",
        "documentation": "Code for the postal or zip code"
       }
      }
     },
     "auth_ref": []
    },
    "dei_EntityExTransitionPeriod": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "EntityExTransitionPeriod",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Ex Transition Period",
        "documentation": "Indicate if an emerging growth company has elected not to use the extended transition period for complying with any new or revised financial accounting standards."
       }
      }
     },
     "auth_ref": [
      "r7"
     ]
    },
    "dei_SolicitingMaterial": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "SolicitingMaterial",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Soliciting Material",
        "documentation": "Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act."
       }
      }
     },
     "auth_ref": [
      "r5"
     ]
    },
    "dei_CoverAbstract": {
     "xbrltype": "stringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "CoverAbstract",
     "lang": {
      "en-us": {
       "role": {
        "label": "Cover [Abstract]",
        "documentation": "Cover page."
       }
      }
     },
     "auth_ref": []
    },
    "dei_EntityAddressAddressLine1": {
     "xbrltype": "normalizedStringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "EntityAddressAddressLine1",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Address, Address Line One",
        "documentation": "Address Line 1 such as Attn, Building Name, Street Name"
       }
      }
     },
     "auth_ref": []
    },
    "dei_WrittenCommunications": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "WrittenCommunications",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Written Communications",
        "documentation": "Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act."
       }
      }
     },
     "auth_ref": [
      "r6"
     ]
    },
    "dei_SecurityExchangeName": {
     "xbrltype": "edgarExchangeCodeItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "SecurityExchangeName",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Security Exchange Name",
        "documentation": "Name of the Exchange on which a security is registered."
       }
      }
     },
     "auth_ref": [
      "r2"
     ]
    },
    "dei_CityAreaCode": {
     "xbrltype": "normalizedStringItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "CityAreaCode",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "City Area Code",
        "documentation": "Area code of city"
       }
      }
     },
     "auth_ref": []
    },
    "dei_EntityCentralIndexKey": {
     "xbrltype": "centralIndexKeyItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "EntityCentralIndexKey",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Entity Central Index Key",
        "documentation": "A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK."
       }
      }
     },
     "auth_ref": [
      "r1"
     ]
    },
    "dei_PreCommencementIssuerTenderOffer": {
     "xbrltype": "booleanItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "PreCommencementIssuerTenderOffer",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Pre-commencement Issuer Tender Offer",
        "documentation": "Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act."
       }
      }
     },
     "auth_ref": [
      "r3"
     ]
    },
    "dei_NoTradingSymbolFlag": {
     "xbrltype": "trueItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "NoTradingSymbolFlag",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "No Trading Symbol Flag",
        "documentation": "Boolean flag that is true only for a security having no trading symbol."
       }
      }
     },
     "auth_ref": []
    },
    "dei_TradingSymbol": {
     "xbrltype": "tradingSymbolItemType",
     "nsuri": "http://xbrl.sec.gov/dei/2023",
     "localname": "TradingSymbol",
     "presentation": [
      "http://www.renalytixalplc.com/20231031/taxonomy/role/Role_DocumentDocumentAndEntityInformation"
     ],
     "lang": {
      "en-us": {
       "role": {
        "label": "Trading Symbol",
        "documentation": "Trading symbol of an instrument as listed on an exchange."
       }
      }
     },
     "auth_ref": []
    }
   }
  }
 },
 "std_ref": {
  "r0": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Exchange Act",
   "Number": "240",
   "Section": "12",
   "Subsection": "b"
  },
  "r1": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Exchange Act",
   "Number": "240",
   "Section": "12",
   "Subsection": "b-2"
  },
  "r2": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Exchange Act",
   "Number": "240",
   "Section": "12",
   "Subsection": "d1-1"
  },
  "r3": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Exchange Act",
   "Number": "240",
   "Section": "13e",
   "Subsection": "4c"
  },
  "r4": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Exchange Act",
   "Number": "240",
   "Section": "14d",
   "Subsection": "2b"
  },
  "r5": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Exchange Act",
   "Section": "14a",
   "Number": "240",
   "Subsection": "12"
  },
  "r6": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Securities Act",
   "Number": "230",
   "Section": "425"
  },
  "r7": {
   "role": "http://www.xbrl.org/2003/role/presentationRef",
   "Publisher": "SEC",
   "Name": "Securities Act",
   "Number": "7A",
   "Section": "B",
   "Subsection": "2"
  }
 }
}