<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.20.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>32</ContextCount>
  <ElementCount>87</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>38</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>0</UnitCount>
  <MyReports>
    <Report instance="ck0000720064-20200319.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>000001 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bny.com/20200319/role/DocumentAndEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
      <MenuCategory></MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="ck0000720064-20200319.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>020000 - Document - Risk/Return Summary {Unlabeled} - BNY Mellon California AMT-Free Municipal Bond Fund, Inc.</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bny.com/20200319/role/DocumentRiskReturnSummaryUnlabeledBNYMellonCaliforniaAMTFreeMunicipalBondFundInc</Role>
      <ShortName>Risk/Return Summary- BNY Mellon California AMT-Free Municipal Bond Fund, Inc.</ShortName>
      <MenuCategory></MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="ck0000720064-20200319.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>020001 - Disclosure - Risk/Return Detail Data {Elements} - BNY Mellon California AMT-Free Municipal Bond Fund, Inc.</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bny.com/20200319/role/DisclosureRiskReturnDetailDataElementsBNYMellonCaliforniaAMTFreeMunicipalBondFundInc</Role>
      <ShortName>Risk/Return Detail Data- BNY Mellon California AMT-Free Municipal Bond Fund, Inc.</ShortName>
      <MenuCategory></MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="ck0000720064-20200319.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>020002 - Document - Risk/Return Summary {Unlabeled} - BNY Mellon Intermediate Municipal Bond Fund, Inc.</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bny.com/20200319/role/DocumentRiskReturnSummaryUnlabeledBNYMellonIntermediateMunicipalBondFundInc</Role>
      <ShortName>Risk/Return Summary- BNY Mellon Intermediate Municipal Bond Fund, Inc.</ShortName>
      <MenuCategory></MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="ck0000720064-20200319.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>020003 - Disclosure - Risk/Return Detail Data {Elements} - BNY Mellon Intermediate Municipal Bond Fund, Inc.</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bny.com/20200319/role/DisclosureRiskReturnDetailDataElementsBNYMellonIntermediateMunicipalBondFundInc</Role>
      <ShortName>Risk/Return Detail Data- BNY Mellon Intermediate Municipal Bond Fund, Inc.</ShortName>
      <MenuCategory></MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="ck0000720064-20200319.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>020004 - Document - Risk/Return Summary {Unlabeled} - BNY Mellon Equity Income Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bny.com/20200319/role/DocumentRiskReturnSummaryUnlabeledBNYMellonEquityIncomeFund</Role>
      <ShortName>Risk/Return Summary- BNY Mellon Equity Income Fund</ShortName>
      <MenuCategory></MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="ck0000720064-20200319.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>020005 - Disclosure - Risk/Return Detail Data {Elements} - BNY Mellon Equity Income Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bny.com/20200319/role/DisclosureRiskReturnDetailDataElementsBNYMellonEquityIncomeFund</Role>
      <ShortName>Risk/Return Detail Data- BNY Mellon Equity Income Fund</ShortName>
      <MenuCategory></MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="ck0000720064-20200319.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>020006 - Document - Risk/Return Summary {Unlabeled} - BNY Mellon New York Tax Exempt Bond Fund, Inc.</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bny.com/20200319/role/DocumentRiskReturnSummaryUnlabeledBNYMellonNewYorkTaxExemptBondFundInc</Role>
      <ShortName>Risk/Return Summary- BNY Mellon New York Tax Exempt Bond Fund, Inc.</ShortName>
      <MenuCategory></MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="ck0000720064-20200319.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>020007 - Disclosure - Risk/Return Detail Data {Elements} - BNY Mellon New York Tax Exempt Bond Fund, Inc.</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bny.com/20200319/role/DisclosureRiskReturnDetailDataElementsBNYMellonNewYorkTaxExemptBondFundInc</Role>
      <ShortName>Risk/Return Detail Data- BNY Mellon New York Tax Exempt Bond Fund, Inc.</ShortName>
      <MenuCategory></MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="ck0000720064-20200319.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>020008 - Document - Risk/Return Summary {Unlabeled} - BNY Mellon Sustainable U.S. Equity Fund, Inc.</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bny.com/20200319/role/DocumentRiskReturnSummaryUnlabeledBNYMellonSustainableUSEquityFundInc</Role>
      <ShortName>Risk/Return Summary- BNY Mellon Sustainable U.S. Equity Fund, Inc.</ShortName>
      <MenuCategory></MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="ck0000720064-20200319.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>020009 - Disclosure - Risk/Return Detail Data {Elements} - BNY Mellon Sustainable U.S. Equity Fund, Inc.</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bny.com/20200319/role/DisclosureRiskReturnDetailDataElementsBNYMellonSustainableUSEquityFundInc</Role>
      <ShortName>Risk/Return Detail Data- BNY Mellon Sustainable U.S. Equity Fund, Inc.</ShortName>
      <MenuCategory></MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="ck0000720064-20200319.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>020010 - Document - Risk/Return Summary {Unlabeled} - BNY Mellon Emerging Markets Securities Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bny.com/20200319/role/DocumentRiskReturnSummaryUnlabeledBNYMellonEmergingMarketsSecuritiesFund</Role>
      <ShortName>Risk/Return Summary- BNY Mellon Emerging Markets Securities Fund</ShortName>
      <MenuCategory></MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="ck0000720064-20200319.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>020011 - Disclosure - Risk/Return Detail Data {Elements} - BNY Mellon Emerging Markets Securities Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bny.com/20200319/role/DisclosureRiskReturnDetailDataElementsBNYMellonEmergingMarketsSecuritiesFund</Role>
      <ShortName>Risk/Return Detail Data- BNY Mellon Emerging Markets Securities Fund</ShortName>
      <MenuCategory></MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="ck0000720064-20200319.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>020012 - Document - Risk/Return Summary {Unlabeled} - BNY Mellon Select Managers Small Cap Growth Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bny.com/20200319/role/DocumentRiskReturnSummaryUnlabeledBNYMellonSelectManagersSmallCapGrowthFund</Role>
      <ShortName>Risk/Return Summary- BNY Mellon Select Managers Small Cap Growth Fund</ShortName>
      <MenuCategory></MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="ck0000720064-20200319.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>020013 - Disclosure - Risk/Return Detail Data {Elements} - BNY Mellon Select Managers Small Cap Growth Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bny.com/20200319/role/DisclosureRiskReturnDetailDataElementsBNYMellonSelectManagersSmallCapGrowthFund</Role>
      <ShortName>Risk/Return Detail Data- BNY Mellon Select Managers Small Cap Growth Fund</ShortName>
      <MenuCategory></MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="ck0000720064-20200319.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>040000 - Disclosure - Risk/Return Detail Data {Elements}</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/rr/role/RiskReturnDetailData</Role>
      <ShortName>Risk/Return Detail Data</ShortName>
      <MenuCategory></MenuCategory>
      <Position>16</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File>ck0000720064-20200319.xml</File>
    <File>ck0000720064-20200319.xsd</File>
    <File>ck0000720064-20200319_cal.xml</File>
    <File>ck0000720064-20200319_def.xml</File>
    <File>ck0000720064-20200319_lab.xml</File>
    <File>ck0000720064-20200319_pre.xml</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy>http://xbrl.sec.gov/dei/2018-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://xbrl.sec.gov/rr/2018-01-31</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
