<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.26.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>28</ContextCount>
  <ElementCount>94</ElementCount>
  <EntityCount>2</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>3</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>6</UnitCount>
  <MyReports>
    <Report instance="nuv-n2asr_032726.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>995470 - Disclosure - N-2</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/cef/role/N2</Role>
      <ShortName>N-2</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="ex99-s.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>995210 - Document - Submission</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/ffd/role/document/submissionTable</Role>
      <ShortName>Submission</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="ex99-s.htm">
      <IsDefault>true</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>995211 - Document - Offerings</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/ffd/role/document/feesOfferingTable</Role>
      <ShortName>Offerings</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="ex99-s.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>995215 - Document - Fees Summary</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/ffd/role/document/feesSummaryTable</Role>
      <ShortName>Fees Summary</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File>nuv-20260327.xsd</File>
    <File>nuv-20260327_def.xml</File>
    <File>nuv-20260327_lab.xml</File>
    <File>nuv-20260327_pre.xml</File>
    <File doctype="N-2ASR" isN2Prospectus="true" isUsgaap="true" original="nuv-n2asr_032726.htm">nuv-n2asr_032726.htm</File>
    <File doctype="EX-FILING FEES" original="ex99-s.htm">ex99-s.htm</File>
  </InputFiles>
  <SupplementalFiles>
    <File>g799728g58b43.jpg</File>
  </SupplementalFiles>
  <BaseTaxonomies>
    <BaseTaxonomy items="36">http://fasb.org/us-gaap/2025</BaseTaxonomy>
    <BaseTaxonomy items="88">http://xbrl.sec.gov/cef/2025</BaseTaxonomy>
    <BaseTaxonomy items="38">http://xbrl.sec.gov/dei/2025</BaseTaxonomy>
    <BaseTaxonomy items="30">http://xbrl.sec.gov/ffd/2025</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>false</HasCalculationLinkbase>
</FilingSummary>
