<?xml version="1.0" encoding="utf-8"?>
<xbrl
  xml:lang="en-US"
  xmlns="http://www.xbrl.org/2003/instance"
  xmlns:dei="http://xbrl.sec.gov/dei/2022"
  xmlns:link="http://www.xbrl.org/2003/linkbase"
  xmlns:xlink="http://www.w3.org/1999/xlink">
    <link:schemaRef xlink:href="udmy-20230109.xsd" xlink:type="simple"/>
    <context id="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001607939</identifier>
        </entity>
        <period>
            <startDate>2023-01-09</startDate>
            <endDate>2023-01-09</endDate>
        </period>
    </context>
    <dei:EntityCentralIndexKey
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xMC9mcmFnOjNiYzljMDIwNDZhMTQ1NTRhMDVkN2VhNGQ5YzUzMmI4L3RhYmxlOjZiZjhiNzljZWM5OTQzYzRhMWI5MmNlM2IyMTQzYzRkL3RhYmxlcmFuZ2U6NmJmOGI3OWNlYzk5NDNjNGExYjkyY2UzYjIxNDNjNGRfMi0xLTEtMS0xMTY2NDU_8691f694-3e60-4a63-bcb0-2fafccea41c7">0001607939</dei:EntityCentralIndexKey>
    <dei:AmendmentFlag
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xMC9mcmFnOjNiYzljMDIwNDZhMTQ1NTRhMDVkN2VhNGQ5YzUzMmI4L3RhYmxlOjZiZjhiNzljZWM5OTQzYzRhMWI5MmNlM2IyMTQzYzRkL3RhYmxlcmFuZ2U6NmJmOGI3OWNlYzk5NDNjNGExYjkyY2UzYjIxNDNjNGRfMy0xLTEtMS0xMTY2NDU_9f96cb4c-dd28-458d-87ca-271e64fbdaa2">false</dei:AmendmentFlag>
    <dei:DocumentType
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xL2ZyYWc6MTYwMmUzM2YyOThmNDEwMjk0MmEwNDI3Y2MxYjU0OWQvdGV4dHJlZ2lvbjoxNjAyZTMzZjI5OGY0MTAyOTQyYTA0MjdjYzFiNTQ5ZF8xNTkw_78bb91e5-b70f-4d30-ac6a-9812cf60dd84">8-K</dei:DocumentType>
    <dei:DocumentPeriodEndDate
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xL2ZyYWc6MTYwMmUzM2YyOThmNDEwMjk0MmEwNDI3Y2MxYjU0OWQvdGV4dHJlZ2lvbjoxNjAyZTMzZjI5OGY0MTAyOTQyYTA0MjdjYzFiNTQ5ZF8yMjg_a6b7912c-f649-42d2-8575-c210aaca6ebf">2023-01-09</dei:DocumentPeriodEndDate>
    <dei:EntityRegistrantName
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xL2ZyYWc6MTYwMmUzM2YyOThmNDEwMjk0MmEwNDI3Y2MxYjU0OWQvdGV4dHJlZ2lvbjoxNjAyZTMzZjI5OGY0MTAyOTQyYTA0MjdjYzFiNTQ5ZF8xNTky_d379c825-5d5f-4536-9891-62921a4d863d">Udemy, Inc.</dei:EntityRegistrantName>
    <dei:EntityIncorporationStateCountryCode
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xL2ZyYWc6MTYwMmUzM2YyOThmNDEwMjk0MmEwNDI3Y2MxYjU0OWQvdGFibGU6YzdhZmQ1Yzc1ZWY4NGQwOThjZTQ4NjI1ZmE3YTQ4MWMvdGFibGVyYW5nZTpjN2FmZDVjNzVlZjg0ZDA5OGNlNDg2MjVmYTdhNDgxY18wLTAtMS0zLTExNjY0NQ_2f398350-b5f2-426f-b1f1-23bca31ed5ea">DE</dei:EntityIncorporationStateCountryCode>
    <dei:EntityFileNumber
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xL2ZyYWc6MTYwMmUzM2YyOThmNDEwMjk0MmEwNDI3Y2MxYjU0OWQvdGFibGU6YzdhZmQ1Yzc1ZWY4NGQwOThjZTQ4NjI1ZmE3YTQ4MWMvdGFibGVyYW5nZTpjN2FmZDVjNzVlZjg0ZDA5OGNlNDg2MjVmYTdhNDgxY18wLTMtMS0xLTExNjY0NQ_8bc39407-0c2f-4b81-9c1e-884c0838e40c">001-40956</dei:EntityFileNumber>
    <dei:EntityTaxIdentificationNumber
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xL2ZyYWc6MTYwMmUzM2YyOThmNDEwMjk0MmEwNDI3Y2MxYjU0OWQvdGFibGU6YzdhZmQ1Yzc1ZWY4NGQwOThjZTQ4NjI1ZmE3YTQ4MWMvdGFibGVyYW5nZTpjN2FmZDVjNzVlZjg0ZDA5OGNlNDg2MjVmYTdhNDgxY18wLTQtMS0xLTExNjY0NQ_7ea006ab-50fc-4fc8-9d9e-fa09657d2293">27-1779864</dei:EntityTaxIdentificationNumber>
    <dei:EntityAddressAddressLine1
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xL2ZyYWc6MTYwMmUzM2YyOThmNDEwMjk0MmEwNDI3Y2MxYjU0OWQvdGFibGU6YzdhZmQ1Yzc1ZWY4NGQwOThjZTQ4NjI1ZmE3YTQ4MWMvdGFibGVyYW5nZTpjN2FmZDVjNzVlZjg0ZDA5OGNlNDg2MjVmYTdhNDgxY18zLTAtMS0xLTExNjY0NS90ZXh0cmVnaW9uOmZmZGNkMWFlZDY1NDQ0MTY5NGVkYzlkYTExMjY0ZWI5XzQ_2aaa3b6a-ab73-4ef1-a7c1-1d0fd6434f49">600 Harrison Street</dei:EntityAddressAddressLine1>
    <dei:EntityAddressAddressLine2
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xL2ZyYWc6MTYwMmUzM2YyOThmNDEwMjk0MmEwNDI3Y2MxYjU0OWQvdGFibGU6YzdhZmQ1Yzc1ZWY4NGQwOThjZTQ4NjI1ZmE3YTQ4MWMvdGFibGVyYW5nZTpjN2FmZDVjNzVlZjg0ZDA5OGNlNDg2MjVmYTdhNDgxY18zLTAtMS0xLTExNjY0NS90ZXh0cmVnaW9uOmZmZGNkMWFlZDY1NDQ0MTY5NGVkYzlkYTExMjY0ZWI5Xzg_b8fb69b3-8ec2-42f5-aa73-7d910b17510a">3rd Floor</dei:EntityAddressAddressLine2>
    <dei:EntityAddressCityOrTown
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xL2ZyYWc6MTYwMmUzM2YyOThmNDEwMjk0MmEwNDI3Y2MxYjU0OWQvdGFibGU6YzdhZmQ1Yzc1ZWY4NGQwOThjZTQ4NjI1ZmE3YTQ4MWMvdGFibGVyYW5nZTpjN2FmZDVjNzVlZjg0ZDA5OGNlNDg2MjVmYTdhNDgxY180LTAtMS0xLTExNjY0NS90ZXh0cmVnaW9uOjdlYzZmN2I3ZmYyNzRmMmU5MjVhODc1ZjM3MzI0MGQ3XzQ_e9d1a3d3-853c-46d4-91a8-e865a36cb5af">San Francisco</dei:EntityAddressCityOrTown>
    <dei:EntityAddressStateOrProvince
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xL2ZyYWc6MTYwMmUzM2YyOThmNDEwMjk0MmEwNDI3Y2MxYjU0OWQvdGFibGU6YzdhZmQ1Yzc1ZWY4NGQwOThjZTQ4NjI1ZmE3YTQ4MWMvdGFibGVyYW5nZTpjN2FmZDVjNzVlZjg0ZDA5OGNlNDg2MjVmYTdhNDgxY180LTAtMS0xLTExNjY0NS90ZXh0cmVnaW9uOjdlYzZmN2I3ZmYyNzRmMmU5MjVhODc1ZjM3MzI0MGQ3Xzg_302287c8-1e7c-4430-8d4e-75d15ab4029f">CA</dei:EntityAddressStateOrProvince>
    <dei:EntityAddressPostalZipCode
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xL2ZyYWc6MTYwMmUzM2YyOThmNDEwMjk0MmEwNDI3Y2MxYjU0OWQvdGFibGU6YzdhZmQ1Yzc1ZWY4NGQwOThjZTQ4NjI1ZmE3YTQ4MWMvdGFibGVyYW5nZTpjN2FmZDVjNzVlZjg0ZDA5OGNlNDg2MjVmYTdhNDgxY180LTQtMS0xLTExNjY0NQ_e51d5b02-34db-4829-9bbf-ef3dc5da0979">94107</dei:EntityAddressPostalZipCode>
    <dei:CityAreaCode
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xL2ZyYWc6MTYwMmUzM2YyOThmNDEwMjk0MmEwNDI3Y2MxYjU0OWQvdGV4dHJlZ2lvbjoxNjAyZTMzZjI5OGY0MTAyOTQyYTA0MjdjYzFiNTQ5ZF8xNTg2_383a2aae-2412-4042-9080-3f7586d25c18">415</dei:CityAreaCode>
    <dei:LocalPhoneNumber
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xL2ZyYWc6MTYwMmUzM2YyOThmNDEwMjk0MmEwNDI3Y2MxYjU0OWQvdGV4dHJlZ2lvbjoxNjAyZTMzZjI5OGY0MTAyOTQyYTA0MjdjYzFiNTQ5ZF8xNTgz_ebc9827f-fe96-4c69-8542-984582758166">813-1710</dei:LocalPhoneNumber>
    <dei:WrittenCommunications
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xL2ZyYWc6MTYwMmUzM2YyOThmNDEwMjk0MmEwNDI3Y2MxYjU0OWQvdGV4dHJlZ2lvbjoxNjAyZTMzZjI5OGY0MTAyOTQyYTA0MjdjYzFiNTQ5ZF8xNTg4_747b5e8b-2722-45ed-8cba-e4e83fcd85cd">false</dei:WrittenCommunications>
    <dei:SolicitingMaterial
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xL2ZyYWc6MTYwMmUzM2YyOThmNDEwMjk0MmEwNDI3Y2MxYjU0OWQvdGV4dHJlZ2lvbjoxNjAyZTMzZjI5OGY0MTAyOTQyYTA0MjdjYzFiNTQ5ZF8xNTg5_d97aa4bb-82fb-4610-85e0-f97e96d5ce8e">false</dei:SolicitingMaterial>
    <dei:PreCommencementTenderOffer
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xL2ZyYWc6MTYwMmUzM2YyOThmNDEwMjk0MmEwNDI3Y2MxYjU0OWQvdGV4dHJlZ2lvbjoxNjAyZTMzZjI5OGY0MTAyOTQyYTA0MjdjYzFiNTQ5ZF8xNTk4_84234545-cc0e-4f11-a72c-10704f6adf81">false</dei:PreCommencementTenderOffer>
    <dei:PreCommencementIssuerTenderOffer
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xL2ZyYWc6MTYwMmUzM2YyOThmNDEwMjk0MmEwNDI3Y2MxYjU0OWQvdGV4dHJlZ2lvbjoxNjAyZTMzZjI5OGY0MTAyOTQyYTA0MjdjYzFiNTQ5ZF8xNTkz_a52bc0dd-4474-437f-9661-b92e7ba361da">false</dei:PreCommencementIssuerTenderOffer>
    <dei:Security12bTitle
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xL2ZyYWc6MTYwMmUzM2YyOThmNDEwMjk0MmEwNDI3Y2MxYjU0OWQvdGFibGU6YTUwYjdiNGM4YjkxNGFlNTkzMGQ4OTc2OGQ4YzU2OGEvdGFibGVyYW5nZTphNTBiN2I0YzhiOTE0YWU1OTMwZDg5NzY4ZDhjNTY4YV8xLTAtMS0xLTExNjY0NQ_9cd59dc8-6138-49a6-a276-fea660ddabf0">Common Stock, $0.00001 par value per share</dei:Security12bTitle>
    <dei:TradingSymbol
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xL2ZyYWc6MTYwMmUzM2YyOThmNDEwMjk0MmEwNDI3Y2MxYjU0OWQvdGFibGU6YTUwYjdiNGM4YjkxNGFlNTkzMGQ4OTc2OGQ4YzU2OGEvdGFibGVyYW5nZTphNTBiN2I0YzhiOTE0YWU1OTMwZDg5NzY4ZDhjNTY4YV8xLTItMS0xLTExNjY0NQ_b7f660c7-fd22-4066-81b7-3109bbd73c96">UDMY</dei:TradingSymbol>
    <dei:SecurityExchangeName
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xL2ZyYWc6MTYwMmUzM2YyOThmNDEwMjk0MmEwNDI3Y2MxYjU0OWQvdGFibGU6YTUwYjdiNGM4YjkxNGFlNTkzMGQ4OTc2OGQ4YzU2OGEvdGFibGVyYW5nZTphNTBiN2I0YzhiOTE0YWU1OTMwZDg5NzY4ZDhjNTY4YV8xLTQtMS0xLTExNjY0NS90ZXh0cmVnaW9uOmY3MDkwYzRkZjVhOTRhMTU5ZTU2ODQyMzMyNmQ3NjFjXzQ_ce0f097e-53a3-4486-9201-ed32e5c70206">NASDAQ</dei:SecurityExchangeName>
    <dei:EntityEmergingGrowthCompany
      contextRef="ic62a8fc0348e4ae28f50d9f036c5c9b2_D20230109-20230109"
      id="id3VybDovL2RvY3MudjEvZG9jOjAwOTA3ZDY2YTc1NDQ2MTU4ODE5ZDc5Y2JjNWU2MzcyL3NlYzowMDkwN2Q2NmE3NTQ0NjE1ODgxOWQ3OWNiYzVlNjM3Ml8xL2ZyYWc6MTYwMmUzM2YyOThmNDEwMjk0MmEwNDI3Y2MxYjU0OWQvdGV4dHJlZ2lvbjoxNjAyZTMzZjI5OGY0MTAyOTQyYTA0MjdjYzFiNTQ5ZF8yMTk5MDIzMjU3MTg0_9ca53673-8a79-4c07-b769-a9f6ea13582c">false</dei:EntityEmergingGrowthCompany>
</xbrl>
