<?xml version='1.0' encoding='UTF-8'?>
<FilingSummary>
  <Version>3.8.0.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>527</ContextCount>
  <ElementCount>455</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>88</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>10</UnitCount>
  <MyReports>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0001000 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/DocumentAndEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>1001000 - Statement - CONSOLIDATED BALANCE SHEETS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/ConsolidatedBalanceSheets</Role>
      <ShortName>CONSOLIDATED BALANCE SHEETS</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>1001501 - Statement - CONSOLIDATED BALANCE SHEETS (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/ConsolidatedBalanceSheetsParenthetical</Role>
      <ShortName>CONSOLIDATED BALANCE SHEETS (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>1002000 - Statement - CONSOLIDATED STATEMENTS OF OPERATIONS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/ConsolidatedStatementsOfOperations</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF OPERATIONS</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>1003000 - Statement - CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/ConsolidatedStatementsOfComprehensiveIncome</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>1004000 - Statement - CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/ConsolidatedStatementsOfChangesInShareholdersEquity</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>1004501 - Statement - CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/ConsolidatedStatementsOfChangesInShareholdersEquityParenthetical</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>1005000 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/ConsolidatedStatementsOfCashFlows</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF CASH FLOWS</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>2101100 - Disclosure - Basis of Presentation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/BasisOfPresentation</Role>
      <ShortName>Basis of Presentation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>2102100 - Disclosure - Stock-Based Compensation Plan</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/StockBasedCompensationPlan</Role>
      <ShortName>Stock-Based Compensation Plan</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>2103100 - Disclosure - Securities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/Securities</Role>
      <ShortName>Securities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>2104100 - Disclosure - Loans</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/Loans</Role>
      <ShortName>Loans</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>2105100 - Disclosure - Allowance for Loan Losses</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/AllowanceForLoanLosses</Role>
      <ShortName>Allowance for Loan Losses</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>2106100 - Disclosure - Earnings Per Share</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/EarningsPerShare</Role>
      <ShortName>Earnings Per Share</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>2107100 - Disclosure - Segment Reporting</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/SegmentReporting</Role>
      <ShortName>Segment Reporting</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>2109100 - Disclosure - Fair Value Measurements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/FairValueMeasurements</Role>
      <ShortName>Fair Value Measurements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>2110100 - Disclosure - Financial Instruments with Off-Balance Sheet Risk</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/FinancialInstrumentsWithOffBalanceSheetRisk</Role>
      <ShortName>Financial Instruments with Off-Balance Sheet Risk</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>2111100 - Disclosure - Recent Accounting Pronouncements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/RecentAccountingPronouncements</Role>
      <ShortName>Recent Accounting Pronouncements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>2112100 - Disclosure - Commitments and Contingent Liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/CommitmentsAndContingentLiabilities</Role>
      <ShortName>Commitments and Contingent Liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>2116100 - Disclosure - Low Income Housing Tax Credits</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LowIncomeHousingTaxCredits</Role>
      <ShortName>Low Income Housing Tax Credits</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>2117100 - Disclosure - Bank Owned Life Insurance</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/BankOwnedLifeInsurance</Role>
      <ShortName>Bank Owned Life Insurance</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>2118100 - Disclosure - Mergers and Acquisitions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/MergersAndAcquisitions</Role>
      <ShortName>Mergers and Acquisitions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>2119100 - Disclosure - Other Income and Other Operating Expenses</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/OtherIncomeAndOtherOperatingExpenses</Role>
      <ShortName>Other Income and Other Operating Expenses</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>2120100 - Disclosure - Derivatives</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/Derivatives</Role>
      <ShortName>Derivatives</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>2121100 - Disclosure - Goodwill and Intangible Assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/GoodwillAndIntangibleAssets</Role>
      <ShortName>Goodwill and Intangible Assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>2211201 - Disclosure - Recent Accounting Pronouncements (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/RecentAccountingPronouncementsPolicies</Role>
      <ShortName>Recent Accounting Pronouncements (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/RecentAccountingPronouncements</ParentRole>
      <Position>26</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>2302301 - Disclosure - Stock-Based Compensation Plan (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/StockBasedCompensationPlanTables</Role>
      <ShortName>Stock-Based Compensation Plan (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/StockBasedCompensationPlan</ParentRole>
      <Position>27</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>2303301 - Disclosure - Securities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/SecuritiesTables</Role>
      <ShortName>Securities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/Securities</ParentRole>
      <Position>28</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>2304301 - Disclosure - Loans (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LoansTables</Role>
      <ShortName>Loans (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/Loans</ParentRole>
      <Position>29</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>2305301 - Disclosure - Allowance for Loan Losses (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/AllowanceForLoanLossesTables</Role>
      <ShortName>Allowance for Loan Losses (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/AllowanceForLoanLosses</ParentRole>
      <Position>30</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>2306301 - Disclosure - Earnings Per Share (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/EarningsPerShareTables</Role>
      <ShortName>Earnings Per Share (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/EarningsPerShare</ParentRole>
      <Position>31</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>2307301 - Disclosure - Segment Reporting (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/SegmentReportingTables</Role>
      <ShortName>Segment Reporting (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/SegmentReporting</ParentRole>
      <Position>32</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>2309301 - Disclosure - Fair Value Measurements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/FairValueMeasurementsTables</Role>
      <ShortName>Fair Value Measurements (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/FairValueMeasurements</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>2310301 - Disclosure - Financial Instruments with Off-Balance Sheet Risk (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/FinancialInstrumentsWithOffBalanceSheetRiskTables</Role>
      <ShortName>Financial Instruments with Off-Balance Sheet Risk (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/FinancialInstrumentsWithOffBalanceSheetRisk</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>2318301 - Disclosure - Mergers and Acquisitions (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/MergersAndAcquisitionsTables</Role>
      <ShortName>Mergers and Acquisitions (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/MergersAndAcquisitions</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>2319301 - Disclosure - Other Income and Other Operating Expenses (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/OtherIncomeAndOtherOperatingExpensesTables</Role>
      <ShortName>Other Income and Other Operating Expenses (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/OtherIncomeAndOtherOperatingExpenses</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>2320301 - Disclosure - Derivatives (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/DerivativesTables</Role>
      <ShortName>Derivatives (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/Derivatives</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>2321301 - Disclosure - Goodwill and Intangible Assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/GoodwillAndIntangibleAssetsTables</Role>
      <ShortName>Goodwill and Intangible Assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/GoodwillAndIntangibleAssets</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>2401401 - Disclosure - Basis of Presentation - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/BasisOfPresentationAdditionalInformationDetails</Role>
      <ShortName>Basis of Presentation - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>39</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>2402402 - Disclosure - Stock-Based Compensation Plan - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/StockBasedCompensationPlanNarrativeDetails</Role>
      <ShortName>Stock-Based Compensation Plan - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>40</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>2402403 - Disclosure - Stock-Based Compensation Plan - Schedule of Fair Value Assumptions Stock Options (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/StockBasedCompensationPlanScheduleOfFairValueAssumptionsStockOptionsDetails</Role>
      <ShortName>Stock-Based Compensation Plan - Schedule of Fair Value Assumptions Stock Options (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>41</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>2402404 - Disclosure - Stock-Based Compensation Plan - Stock options outstanding activity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/StockBasedCompensationPlanStockOptionsOutstandingActivityDetails</Role>
      <ShortName>Stock-Based Compensation Plan - Stock options outstanding activity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>42</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>2403402 - Disclosure - Securities - Amortized Costs and Fair Values of Securities Held to Maturity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/SecuritiesAmortizedCostsAndFairValuesOfSecuritiesHeldToMaturityDetails</Role>
      <ShortName>Securities - Amortized Costs and Fair Values of Securities Held to Maturity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>43</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>2403403 - Disclosure - Securities - Amortized Cost and Fair Value of Securities Held to Maturity by Contractual Maturity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/SecuritiesAmortizedCostAndFairValueOfSecuritiesHeldToMaturityByContractualMaturityDetails</Role>
      <ShortName>Securities - Amortized Cost and Fair Value of Securities Held to Maturity by Contractual Maturity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>44</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>2403404 - Disclosure - Securities - Amortized Costs and Fair Values of Securities Available for Sale (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/SecuritiesAmortizedCostsAndFairValuesOfSecuritiesAvailableForSaleDetails</Role>
      <ShortName>Securities - Amortized Costs and Fair Values of Securities Available for Sale (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>45</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>2403405 - Disclosure - Securities - Amortized Cost and Fair Value of Securities Available for Sale by Contractual Maturity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/SecuritiesAmortizedCostAndFairValueOfSecuritiesAvailableForSaleByContractualMaturityDetails</Role>
      <ShortName>Securities - Amortized Cost and Fair Value of Securities Available for Sale by Contractual Maturity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>46</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>2403406 - Disclosure - Securities - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/SecuritiesNarrativeDetails</Role>
      <ShortName>Securities - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>47</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>2403407 - Disclosure - Securities - Investments in Unrealized Loss Position (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/SecuritiesInvestmentsInUnrealizedLossPositionDetails</Role>
      <ShortName>Securities - Investments in Unrealized Loss Position (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>48</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>2404402 - Disclosure - Loans - Composition of Loans Held for Investment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LoansCompositionOfLoansHeldForInvestmentDetails</Role>
      <ShortName>Loans - Composition of Loans Held for Investment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>49</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>2404403 - Disclosure - Loans - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LoansNarrativeDetails</Role>
      <ShortName>Loans - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>50</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>2404404 - Disclosure - Loans - Schedule of Changes in Accretable Yield for Purchased Impaired Loans (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LoansScheduleOfChangesInAccretableYieldForPurchasedImpairedLoansDetails</Role>
      <ShortName>Loans - Schedule of Changes in Accretable Yield for Purchased Impaired Loans (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>51</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>2404405 - Disclosure - Loans - Non-Accrual Loans Past Due (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LoansNonAccrualLoansPastDueDetails</Role>
      <ShortName>Loans - Non-Accrual Loans Past Due (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>52</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>2404406 - Disclosure - Loans - Risk Profile Based Upon Payment Activity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LoansRiskProfileBasedUponPaymentActivityDetails</Role>
      <ShortName>Loans - Risk Profile Based Upon Payment Activity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>53</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>2404407 - Disclosure - Loans - Summary of Loan Classifications by Class of Loan (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LoansSummaryOfLoanClassificationsByClassOfLoanDetails</Role>
      <ShortName>Loans - Summary of Loan Classifications by Class of Loan (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>54</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>2404408 - Disclosure - Loans - Loans Identified as Impaired by Class of Loan (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LoansLoansIdentifiedAsImpairedByClassOfLoanDetails</Role>
      <ShortName>Loans - Loans Identified as Impaired by Class of Loan (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>55</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>2404409 - Disclosure - Loans - Impaired Loans by Average Recorded Investment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LoansImpairedLoansByAverageRecordedInvestmentDetails</Role>
      <ShortName>Loans - Impaired Loans by Average Recorded Investment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>56</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>2405402 - Disclosure - Allowance for Loan Losses - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/AllowanceForLoanLossesNarrativeDetails</Role>
      <ShortName>Allowance for Loan Losses - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>2405403 - Disclosure - Allowance for Loan Losses (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/AllowanceForLoanLossesDetails</Role>
      <ShortName>Allowance for Loan Losses (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/AllowanceForLoanLossesTables</ParentRole>
      <Position>58</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>2406402 - Disclosure - Earnings Per Share (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/EarningsPerShareDetails</Role>
      <ShortName>Earnings Per Share (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/EarningsPerShareTables</ParentRole>
      <Position>59</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>2407402 - Disclosure - Segment Reporting (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/SegmentReportingDetails</Role>
      <ShortName>Segment Reporting (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/SegmentReportingTables</ParentRole>
      <Position>60</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>2409402 - Disclosure - Fair Value Measurements - Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/FairValueMeasurementsFinancialAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasisDetails</Role>
      <ShortName>Fair Value Measurements - Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>61</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>2409403 - Disclosure - Fair Value Measurements - Changes in Level 3 Assets and Liabilities Measured at Fair Value (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/FairValueMeasurementsChangesInLevel3AssetsAndLiabilitiesMeasuredAtFairValueDetails</Role>
      <ShortName>Fair Value Measurements - Changes in Level 3 Assets and Liabilities Measured at Fair Value (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>2409404 - Disclosure - Fair Value Measurements - Quantitative Information about Level III Fair Value Measurements (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/FairValueMeasurementsQuantitativeInformationAboutLevelIiiFairValueMeasurementsDetails</Role>
      <ShortName>Fair Value Measurements - Quantitative Information about Level III Fair Value Measurements (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>63</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>2409405 - Disclosure - Fair Value Measurements - Difference Between Fair Value and Carrying Amount of Residential Mortgage Loans Held for Sale (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/FairValueMeasurementsDifferenceBetweenFairValueAndCarryingAmountOfResidentialMortgageLoansHeldForSaleDetails</Role>
      <ShortName>Fair Value Measurements - Difference Between Fair Value and Carrying Amount of Residential Mortgage Loans Held for Sale (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>64</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>2409406 - Disclosure - Fair Value Measurements - Estimated Fair Values and Related Carrying Values of Financial Instruments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/FairValueMeasurementsEstimatedFairValuesAndRelatedCarryingValuesOfFinancialInstrumentsDetails</Role>
      <ShortName>Fair Value Measurements - Estimated Fair Values and Related Carrying Values of Financial Instruments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>65</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>2410402 - Disclosure - Financial Instruments with Off-Balance Sheet Risk  - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/FinancialInstrumentsWithOffBalanceSheetRiskNarrativeDetails</Role>
      <ShortName>Financial Instruments with Off-Balance Sheet Risk  - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>66</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>2410403 - Disclosure - Financial Instruments with Off-Balance Sheet Risk - Changes in Allowance for Losses on Mortgage Loans Sold (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/FinancialInstrumentsWithOffBalanceSheetRiskChangesInAllowanceForLossesOnMortgageLoansSoldDetails</Role>
      <ShortName>Financial Instruments with Off-Balance Sheet Risk - Changes in Allowance for Losses on Mortgage Loans Sold (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>67</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>2412401 - Disclosure - Commitments and Contingent Liabilities  - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/CommitmentsAndContingentLiabilitiesNarrativeDetails</Role>
      <ShortName>Commitments and Contingent Liabilities  - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>68</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>2416401 - Disclosure - Low Income Housing Tax Credits (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LowIncomeHousingTaxCreditsDetails</Role>
      <ShortName>Low Income Housing Tax Credits (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/LowIncomeHousingTaxCredits</ParentRole>
      <Position>69</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>2417401 - Disclosure - Bank Owned Life Insurance (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/BankOwnedLifeInsuranceDetails</Role>
      <ShortName>Bank Owned Life Insurance (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/BankOwnedLifeInsurance</ParentRole>
      <Position>70</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>2418402 - Disclosure - Mergers and Acquisitions - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/MergersAndAcquisitionsNarrativeDetails</Role>
      <ShortName>Mergers and Acquisitions - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>71</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>2418403 - Disclosure - Mergers and Acquisitions - Schedule of Fair Value of Identifiable Assets Acquired and Liabilities Assumed (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/MergersAndAcquisitionsScheduleOfFairValueOfIdentifiableAssetsAcquiredAndLiabilitiesAssumedDetails</Role>
      <ShortName>Mergers and Acquisitions - Schedule of Fair Value of Identifiable Assets Acquired and Liabilities Assumed (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>72</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>2418404 - Disclosure - Mergers and Acquisitions - Loans Identified as Impaired at Acquisition Date (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/MergersAndAcquisitionsLoansIdentifiedAsImpairedAtAcquisitionDateDetails</Role>
      <ShortName>Mergers and Acquisitions - Loans Identified as Impaired at Acquisition Date (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>73</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>2418405 - Disclosure - Mergers and Acquisitions - Pro Forma Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/MergersAndAcquisitionsProFormaInformationDetails</Role>
      <ShortName>Mergers and Acquisitions - Pro Forma Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>74</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>2419402 - Disclosure - Other Income and Other Operating Expenses - Schedule of Other Income (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/OtherIncomeAndOtherOperatingExpensesScheduleOfOtherIncomeDetails</Role>
      <ShortName>Other Income and Other Operating Expenses - Schedule of Other Income (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>75</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>2419403 - Disclosure - Other Income and Other Operating Expenses - Schedule of Other Expenses (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/OtherIncomeAndOtherOperatingExpensesScheduleOfOtherExpensesDetails</Role>
      <ShortName>Other Income and Other Operating Expenses - Schedule of Other Expenses (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>76</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>2420402 - Disclosure - Derivatives   - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/DerivativesNarrativeDetails</Role>
      <ShortName>Derivatives   - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>77</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>2420403 - Disclosure - Derivatives  - Derivatives Designated as Cash Flow Hedges (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/DerivativesDerivativesDesignatedAsCashFlowHedgesDetails</Role>
      <ShortName>Derivatives  - Derivatives Designated as Cash Flow Hedges (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>78</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>2420404 - Disclosure - Derivatives  - Two-way Client Interest Rate Swaps not Designated as either Fair Value or Cash Flow Hedges (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/DerivativesTwoWayClientInterestRateSwapsNotDesignatedAsEitherFairValueOrCashFlowHedgesDetails</Role>
      <ShortName>Derivatives  - Two-way Client Interest Rate Swaps not Designated as either Fair Value or Cash Flow Hedges (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>79</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R80.htm</HtmlFileName>
      <LongName>2420405 - Disclosure - Derivatives  - Interest Rate Cap Agreement (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/DerivativesInterestRateCapAgreementDetails</Role>
      <ShortName>Derivatives  - Interest Rate Cap Agreement (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>80</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R81.htm</HtmlFileName>
      <LongName>2421402 - Disclosure - Goodwill and Intangible Assets - Summary of Carrying Amount of Intangible Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/GoodwillAndIntangibleAssetsSummaryOfCarryingAmountOfIntangibleAssetsDetails</Role>
      <ShortName>Goodwill and Intangible Assets - Summary of Carrying Amount of Intangible Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>81</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R82.htm</HtmlFileName>
      <LongName>2421403 - Disclosure - Goodwill and Intangible Assets - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/GoodwillAndIntangibleAssetsNarrativeDetails</Role>
      <ShortName>Goodwill and Intangible Assets - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>82</Position>
    </Report>
    <Report instance="ancx-20170930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R83.htm</HtmlFileName>
      <LongName>2421404 - Disclosure - Goodwill and Intangible Assets - Schedule of Changes in Carrying Amount of Goodwill (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/GoodwillAndIntangibleAssetsScheduleOfChangesInCarryingAmountOfGoodwillDetails</Role>
      <ShortName>Goodwill and Intangible Assets - Schedule of Changes in Carrying Amount of Goodwill (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>83</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File>ancx-20170930.xml</File>
    <File>ancx-20170930.xsd</File>
    <File>ancx-20170930_cal.xml</File>
    <File>ancx-20170930_def.xml</File>
    <File>ancx-20170930_lab.xml</File>
    <File>ancx-20170930_pre.xml</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy>http://xbrl.sec.gov/invest/2013-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://xbrl.sec.gov/dei/2014-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://fasb.org/us-gaap/2017-01-31</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
