<?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/2021"
  xmlns:link="http://www.xbrl.org/2003/linkbase"
  xmlns:xlink="http://www.w3.org/1999/xlink"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <link:schemaRef xlink:href="seer-20220504.xsd" xlink:type="simple"/>
    <context id="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001726445</identifier>
        </entity>
        <period>
            <startDate>2022-01-01</startDate>
            <endDate>2022-03-31</endDate>
        </period>
    </context>
    <dei:DocumentFiscalYearFocus
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M180L2ZyYWc6YTNlYjRlZjI2ZWUyNGM0YjkwM2Q0OTc1YjFiY2IwZWMvdGFibGU6ZTE3NzE4NjNmYWFhNDZmMzg3YzFmNmVkNmQwMTJjM2EvdGFibGVyYW5nZTplMTc3MTg2M2ZhYWE0NmYzODdjMWY2ZWQ2ZDAxMmMzYV8yLTEtMS0xLTg5MDY2_82c82d60-38b5-4f2d-9e76-8f300f42b0e0"
      xsi:nil="true"/>
    <dei:DocumentFiscalPeriodFocus
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M180L2ZyYWc6YTNlYjRlZjI2ZWUyNGM0YjkwM2Q0OTc1YjFiY2IwZWMvdGFibGU6ZTE3NzE4NjNmYWFhNDZmMzg3YzFmNmVkNmQwMTJjM2EvdGFibGVyYW5nZTplMTc3MTg2M2ZhYWE0NmYzODdjMWY2ZWQ2ZDAxMmMzYV8zLTEtMS0xLTg5MDY2_3f9d598a-fbff-4962-a02c-738f04e292b6"
      xsi:nil="true"/>
    <dei:AmendmentFlag
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M180L2ZyYWc6YTNlYjRlZjI2ZWUyNGM0YjkwM2Q0OTc1YjFiY2IwZWMvdGFibGU6ZTE3NzE4NjNmYWFhNDZmMzg3YzFmNmVkNmQwMTJjM2EvdGFibGVyYW5nZTplMTc3MTg2M2ZhYWE0NmYzODdjMWY2ZWQ2ZDAxMmMzYV80LTEtMS0xLTg5MDY2_86a040cd-7221-451b-b568-6833b40fd466">false</dei:AmendmentFlag>
    <dei:EntityCentralIndexKey
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M180L2ZyYWc6YTNlYjRlZjI2ZWUyNGM0YjkwM2Q0OTc1YjFiY2IwZWMvdGFibGU6ZTE3NzE4NjNmYWFhNDZmMzg3YzFmNmVkNmQwMTJjM2EvdGFibGVyYW5nZTplMTc3MTg2M2ZhYWE0NmYzODdjMWY2ZWQ2ZDAxMmMzYV81LTEtMS0xLTg5MDY2_1252cdd9-7ffa-4b2b-aa24-b965f542f06c">0001726445</dei:EntityCentralIndexKey>
    <dei:DocumentType
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M18xL2ZyYWc6MjBhYzhjY2U0YmI2NGExZWJmNDNkMjkwMTZhMjU0MTYvdGV4dHJlZ2lvbjoyMGFjOGNjZTRiYjY0YTFlYmY0M2QyOTAxNmEyNTQxNl8xMjg1_1212722b-f8e2-401c-bf26-517128ca02cf">8-K</dei:DocumentType>
    <dei:DocumentPeriodEndDate
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M18xL2ZyYWc6MjBhYzhjY2U0YmI2NGExZWJmNDNkMjkwMTZhMjU0MTYvdGV4dHJlZ2lvbjoyMGFjOGNjZTRiYjY0YTFlYmY0M2QyOTAxNmEyNTQxNl8xMjg2_618bbf44-e188-4e8d-8610-37d55ec9badb">2022-05-04</dei:DocumentPeriodEndDate>
    <dei:EntityRegistrantName
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M18xL2ZyYWc6MjBhYzhjY2U0YmI2NGExZWJmNDNkMjkwMTZhMjU0MTYvdGV4dHJlZ2lvbjoyMGFjOGNjZTRiYjY0YTFlYmY0M2QyOTAxNmEyNTQxNl8xMjg3_d0074c0a-e568-47b2-85ca-3417d0a2e881">Seer, Inc.</dei:EntityRegistrantName>
    <dei:EntityIncorporationStateCountryCode
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M18xL2ZyYWc6MjBhYzhjY2U0YmI2NGExZWJmNDNkMjkwMTZhMjU0MTYvdGFibGU6Mjc2OGY5YzdlM2ZjNDM4NjliMWQ4MzBmYzQ4ZDExOTAvdGFibGVyYW5nZToyNzY4ZjljN2UzZmM0Mzg2OWIxZDgzMGZjNDhkMTE5MF8wLTAtMS0xLTg5MDY2_76e4058b-83e9-4550-9a95-a2f867784c24">DE</dei:EntityIncorporationStateCountryCode>
    <dei:EntityFileNumber
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M18xL2ZyYWc6MjBhYzhjY2U0YmI2NGExZWJmNDNkMjkwMTZhMjU0MTYvdGFibGU6Mjc2OGY5YzdlM2ZjNDM4NjliMWQ4MzBmYzQ4ZDExOTAvdGFibGVyYW5nZToyNzY4ZjljN2UzZmM0Mzg2OWIxZDgzMGZjNDhkMTE5MF8wLTItMS0xLTg5MDY2_2d1e0350-c185-464c-9184-7aa97a510a48">001-39747</dei:EntityFileNumber>
    <dei:EntityTaxIdentificationNumber
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M18xL2ZyYWc6MjBhYzhjY2U0YmI2NGExZWJmNDNkMjkwMTZhMjU0MTYvdGFibGU6Mjc2OGY5YzdlM2ZjNDM4NjliMWQ4MzBmYzQ4ZDExOTAvdGFibGVyYW5nZToyNzY4ZjljN2UzZmM0Mzg2OWIxZDgzMGZjNDhkMTE5MF8wLTQtMS0xLTg5MDY2_fe1a1ca1-0c37-417b-9b06-5528f29daeed">82-1153150</dei:EntityTaxIdentificationNumber>
    <dei:EntityAddressAddressLine1
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M18xL2ZyYWc6MjBhYzhjY2U0YmI2NGExZWJmNDNkMjkwMTZhMjU0MTYvdGV4dHJlZ2lvbjoyMGFjOGNjZTRiYjY0YTFlYmY0M2QyOTAxNmEyNTQxNl8xMjgy_4d1c3d3f-f601-490e-9963-850a920cba37">3800 Bridge Parkway</dei:EntityAddressAddressLine1>
    <dei:EntityAddressAddressLine2
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M18xL2ZyYWc6MjBhYzhjY2U0YmI2NGExZWJmNDNkMjkwMTZhMjU0MTYvdGV4dHJlZ2lvbjoyMGFjOGNjZTRiYjY0YTFlYmY0M2QyOTAxNmEyNTQxNl8xMjg4_71212ab1-96b2-4a30-b4c9-13c2dfac33f0">Suite 102</dei:EntityAddressAddressLine2>
    <dei:EntityAddressCityOrTown
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M18xL2ZyYWc6MjBhYzhjY2U0YmI2NGExZWJmNDNkMjkwMTZhMjU0MTYvdGV4dHJlZ2lvbjoyMGFjOGNjZTRiYjY0YTFlYmY0M2QyOTAxNmEyNTQxNl8xMjg5_7154ed30-7430-4ffa-9aa9-b806ab86c330">Redwood City</dei:EntityAddressCityOrTown>
    <dei:EntityAddressStateOrProvince
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M18xL2ZyYWc6MjBhYzhjY2U0YmI2NGExZWJmNDNkMjkwMTZhMjU0MTYvdGV4dHJlZ2lvbjoyMGFjOGNjZTRiYjY0YTFlYmY0M2QyOTAxNmEyNTQxNl8xMjgz_f4ce0fa8-e234-4c0d-adb9-5613a8ed8618">CA</dei:EntityAddressStateOrProvince>
    <dei:EntityAddressPostalZipCode
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M18xL2ZyYWc6MjBhYzhjY2U0YmI2NGExZWJmNDNkMjkwMTZhMjU0MTYvdGV4dHJlZ2lvbjoyMGFjOGNjZTRiYjY0YTFlYmY0M2QyOTAxNmEyNTQxNl8zNzI_9fb987e3-44c1-48d7-a090-df16dd0b582b">94065</dei:EntityAddressPostalZipCode>
    <dei:CityAreaCode
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M18xL2ZyYWc6MjBhYzhjY2U0YmI2NGExZWJmNDNkMjkwMTZhMjU0MTYvdGV4dHJlZ2lvbjoyMGFjOGNjZTRiYjY0YTFlYmY0M2QyOTAxNmEyNTQxNl80Mzg_a7497cd4-ab61-49fb-87d8-2a28a179b406">650</dei:CityAreaCode>
    <dei:LocalPhoneNumber
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M18xL2ZyYWc6MjBhYzhjY2U0YmI2NGExZWJmNDNkMjkwMTZhMjU0MTYvdGV4dHJlZ2lvbjoyMGFjOGNjZTRiYjY0YTFlYmY0M2QyOTAxNmEyNTQxNl8xMjkw_033133c2-5823-4839-93ab-58f102af5487">453-0000</dei:LocalPhoneNumber>
    <dei:WrittenCommunications
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M18xL2ZyYWc6MjBhYzhjY2U0YmI2NGExZWJmNDNkMjkwMTZhMjU0MTYvdGFibGU6NWMwYTQ4MmQwOTJmNDIyNmE5MTEwNzU1NWQ1YTI0ZWYvdGFibGVyYW5nZTo1YzBhNDgyZDA5MmY0MjI2YTkxMTA3NTU1ZDVhMjRlZl8wLTAtMS0xLTg5MDY2_ee3695ed-984f-4aaf-9fed-8025c741d2cb">false</dei:WrittenCommunications>
    <dei:SolicitingMaterial
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M18xL2ZyYWc6MjBhYzhjY2U0YmI2NGExZWJmNDNkMjkwMTZhMjU0MTYvdGFibGU6NWMwYTQ4MmQwOTJmNDIyNmE5MTEwNzU1NWQ1YTI0ZWYvdGFibGVyYW5nZTo1YzBhNDgyZDA5MmY0MjI2YTkxMTA3NTU1ZDVhMjRlZl8xLTAtMS0xLTg5MDY2_9ee55a9b-b83f-4c4a-89a2-0cb8d7bb6389">false</dei:SolicitingMaterial>
    <dei:PreCommencementTenderOffer
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M18xL2ZyYWc6MjBhYzhjY2U0YmI2NGExZWJmNDNkMjkwMTZhMjU0MTYvdGFibGU6NWMwYTQ4MmQwOTJmNDIyNmE5MTEwNzU1NWQ1YTI0ZWYvdGFibGVyYW5nZTo1YzBhNDgyZDA5MmY0MjI2YTkxMTA3NTU1ZDVhMjRlZl8yLTAtMS0xLTg5MDY2_a8a1f46b-83c4-40e6-96c8-711f5dc81b7d">false</dei:PreCommencementTenderOffer>
    <dei:PreCommencementIssuerTenderOffer
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M18xL2ZyYWc6MjBhYzhjY2U0YmI2NGExZWJmNDNkMjkwMTZhMjU0MTYvdGFibGU6NWMwYTQ4MmQwOTJmNDIyNmE5MTEwNzU1NWQ1YTI0ZWYvdGFibGVyYW5nZTo1YzBhNDgyZDA5MmY0MjI2YTkxMTA3NTU1ZDVhMjRlZl8zLTAtMS0xLTg5MDY2_b361bf22-a4f6-474d-9915-c141b2dcce2c">false</dei:PreCommencementIssuerTenderOffer>
    <dei:Security12bTitle
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M18xL2ZyYWc6MjBhYzhjY2U0YmI2NGExZWJmNDNkMjkwMTZhMjU0MTYvdGFibGU6ODkwOTRlNDEzMDAwNDUxNmI5ZWU5NDE5NTIwYjhiZmMvdGFibGVyYW5nZTo4OTA5NGU0MTMwMDA0NTE2YjllZTk0MTk1MjBiOGJmY18xLTAtMS0xLTg5MDY2_8f733020-887e-4582-ac07-c4a3b2af442d">Class A Common Stock, par value $0.00001 per share</dei:Security12bTitle>
    <dei:TradingSymbol
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M18xL2ZyYWc6MjBhYzhjY2U0YmI2NGExZWJmNDNkMjkwMTZhMjU0MTYvdGFibGU6ODkwOTRlNDEzMDAwNDUxNmI5ZWU5NDE5NTIwYjhiZmMvdGFibGVyYW5nZTo4OTA5NGU0MTMwMDA0NTE2YjllZTk0MTk1MjBiOGJmY18xLTEtMS0xLTg5MDY2_a0c19a3c-e6ae-419c-a018-1abfa57dfa0e">SEER</dei:TradingSymbol>
    <dei:EntityEmergingGrowthCompany
      contextRef="ib42378abd0054e5ead320e40b6f0bbb4_D20220101-20220331"
      id="id3VybDovL2RvY3MudjEvZG9jOjc4MGRkNDViNDQ5NzRjNzJiM2Q0NWJmOGE2NzdiZDUzL3NlYzo3ODBkZDQ1YjQ0OTc0YzcyYjNkNDViZjhhNjc3YmQ1M18xL2ZyYWc6MjBhYzhjY2U0YmI2NGExZWJmNDNkMjkwMTZhMjU0MTYvdGV4dHJlZ2lvbjoyMGFjOGNjZTRiYjY0YTFlYmY0M2QyOTAxNmEyNTQxNl8xMjg0_1c8e7e50-495c-473d-885b-c8b24ff8bda5">false</dei:EntityEmergingGrowthCompany>
</xbrl>
