<?xml version='1.0' encoding='UTF-8'?>
<FilingSummary>
  <Version>3.8.0.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>516</ContextCount>
  <ElementCount>665</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>110</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>9</UnitCount>
  <MyReports>
    <Report instance="ancx-20171231.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-20171231.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-20171231.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-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>1002000 - Statement - Consolidated Statements of Income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/ConsolidatedStatementsOfIncome</Role>
      <ShortName>Consolidated Statements of Income</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="ancx-20171231.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-20171231.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-20171231.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-20171231.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-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>2101100 - Disclosure - Securities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/Securities</Role>
      <ShortName>Securities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>2101100 - Disclosure - Summary of Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/SummaryOfSignificantAccountingPolicies</Role>
      <ShortName>Summary of Significant Accounting Policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>2102100 - Disclosure - Loans and the Allowance for Loan Losses</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLosses</Role>
      <ShortName>Loans and the Allowance for Loan Losses</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>2103100 - Disclosure - Premises and Equipment</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/PremisesAndEquipment</Role>
      <ShortName>Premises and Equipment</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>2104100 - Disclosure - Deposits</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/Deposits</Role>
      <ShortName>Deposits</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>2105100 - Disclosure - Borrowings</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/Borrowings</Role>
      <ShortName>Borrowings</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>2106100 - Disclosure - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/IncomeTaxes</Role>
      <ShortName>Income Taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>2107100 - 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>16</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>2108100 - 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-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>2109100 - Disclosure - Related Party Transactions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/RelatedPartyTransactions</Role>
      <ShortName>Related Party Transactions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>2110100 - Disclosure - Share Based Compensation Plans</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/ShareBasedCompensationPlans</Role>
      <ShortName>Share Based Compensation Plans</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>2111100 - Disclosure - Capital Requirements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/CapitalRequirements</Role>
      <ShortName>Capital Requirements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>2112100 - 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>21</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>2113100 - Disclosure - Employee Benefits</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/EmployeeBenefits</Role>
      <ShortName>Employee Benefits</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>2114100 - 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-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>2115100 - 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>24</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>2116100 - Disclosure - Parent Corporation Only Statements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/ParentCorporationOnlyStatements</Role>
      <ShortName>Parent Corporation Only Statements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>2116100 - Disclosure - Segment Reporting</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/SegmentReporting</Role>
      <ShortName>Segment Reporting</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>2117100 - 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>27</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>2118100 - 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>28</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>2119100 - Disclosure - Derivatives</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/Derivatives</Role>
      <ShortName>Derivatives</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>29</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>2120100 - Disclosure - Merger with Middleburg Financial Corporation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/MergerWithMiddleburgFinancialCorporation</Role>
      <ShortName>Merger with Middleburg Financial Corporation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>30</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>2201201 - Disclosure - Summary of Significant Accounting Policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/SummaryOfSignificantAccountingPoliciesPolicies</Role>
      <ShortName>Summary of Significant Accounting Policies (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/SummaryOfSignificantAccountingPolicies</ParentRole>
      <Position>31</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>2301301 - 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>32</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>2302301 - Disclosure - Loans and the Allowance for Loan Losses (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLossesTables</Role>
      <ShortName>Loans and the Allowance for Loan Losses (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLosses</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>2303301 - Disclosure - Premises and Equipment (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/PremisesAndEquipmentTables</Role>
      <ShortName>Premises and Equipment (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/PremisesAndEquipment</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>2304301 - Disclosure - Deposits (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/DepositsTables</Role>
      <ShortName>Deposits (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/Deposits</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>2305301 - Disclosure - Borrowings (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/BorrowingsTables</Role>
      <ShortName>Borrowings (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/Borrowings</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>2306301 - Disclosure - Income Taxes (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/IncomeTaxesTables</Role>
      <ShortName>Income Taxes (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/IncomeTaxes</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>2307301 - Disclosure - Commitments and Contingent Liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/CommitmentsAndContingentLiabilitiesTables</Role>
      <ShortName>Commitments and Contingent Liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/CommitmentsAndContingentLiabilities</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>2310301 - Disclosure - Share Based Compensation Plans (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/ShareBasedCompensationPlansTables</Role>
      <ShortName>Share Based Compensation Plans (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/ShareBasedCompensationPlans</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>2311301 - Disclosure - Capital Requirements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/CapitalRequirementsTables</Role>
      <ShortName>Capital Requirements (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/CapitalRequirements</ParentRole>
      <Position>40</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>2312301 - 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>41</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>2314301 - 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>42</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>2315301 - 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>43</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>2316301 - Disclosure - Parent Corporation Only Statements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/ParentCorporationOnlyStatementsTables</Role>
      <ShortName>Parent Corporation Only Statements (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/ParentCorporationOnlyStatements</ParentRole>
      <Position>44</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>2316301 - 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>45</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>2317301 - 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>46</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>2319301 - 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>47</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>2320301 - Disclosure - Merger with Middleburg Financial Corporation (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/MergerWithMiddleburgFinancialCorporationTables</Role>
      <ShortName>Merger with Middleburg Financial Corporation (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/MergerWithMiddleburgFinancialCorporation</ParentRole>
      <Position>48</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>2401402 - Disclosure - Securities (Amortized Cost and Fair Value of AFS and HTM Securities) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/SecuritiesAmortizedCostAndFairValueOfAfsAndHtmSecuritiesDetails</Role>
      <ShortName>Securities (Amortized Cost and Fair Value of AFS and HTM Securities) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/SecuritiesTables</ParentRole>
      <Position>49</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>2401402 - Disclosure - Summary of Significant Accounting Policies (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/SummaryOfSignificantAccountingPoliciesDetailsTextual</Role>
      <ShortName>Summary of Significant Accounting Policies (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/SummaryOfSignificantAccountingPoliciesPolicies</ParentRole>
      <Position>50</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>2401403 - Disclosure - Securities (Amortized Cost and Fair Value by Contractual Maturities) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/SecuritiesAmortizedCostAndFairValueByContractualMaturitiesDetails</Role>
      <ShortName>Securities (Amortized Cost and Fair Value by Contractual Maturities) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/SecuritiesTables</ParentRole>
      <Position>51</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>2401404 - Disclosure - Securities (Restricted Stock) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/SecuritiesRestrictedStockDetails</Role>
      <ShortName>Securities (Restricted Stock) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/SecuritiesTables</ParentRole>
      <Position>52</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>2401405 - Disclosure - Securities (Investment Securities in Unrealized Loss Position) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/SecuritiesInvestmentSecuritiesInUnrealizedLossPositionDetails</Role>
      <ShortName>Securities (Investment Securities in Unrealized Loss Position) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/SecuritiesTables</ParentRole>
      <Position>53</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>2401406 - Disclosure - Securities (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/SecuritiesDetailsTextual</Role>
      <ShortName>Securities (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/SecuritiesTables</ParentRole>
      <Position>54</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>2402402 - Disclosure - Loans and the Allowance for Loan Losses (Composition of Net Loans) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLossesCompositionOfNetLoansDetails</Role>
      <ShortName>Loans and the Allowance for Loan Losses (Composition of Net Loans) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLossesTables</ParentRole>
      <Position>55</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>2402403 - Disclosure - Loans and the Allowance for Loan Losses (Allowance for Loan Losses and Recorded Investment) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLossesAllowanceForLoanLossesAndRecordedInvestmentDetails</Role>
      <ShortName>Loans and the Allowance for Loan Losses (Allowance for Loan Losses and Recorded Investment) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLossesTables</ParentRole>
      <Position>56</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>2402404 - Disclosure - Loans and the Allowance for Loan Losses (Changes in Accretable Yield for Purchased Impaired Loans) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLossesChangesInAccretableYieldForPurchasedImpairedLoansDetails</Role>
      <ShortName>Loans and the Allowance for Loan Losses (Changes in Accretable Yield for Purchased Impaired Loans) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLossesTables</ParentRole>
      <Position>57</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>2402405 - Disclosure - Loans and the Allowance for Loan Losses (Loan Portfolio by Risk Rating) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLossesLoanPortfolioByRiskRatingDetails</Role>
      <ShortName>Loans and the Allowance for Loan Losses (Loan Portfolio by Risk Rating) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLossesTables</ParentRole>
      <Position>58</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>2402406 - Disclosure - Loans and the Allowance for Loan Losses (Risk Portfolio Based on Payment Activity) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLossesRiskPortfolioBasedOnPaymentActivityDetails</Role>
      <ShortName>Loans and the Allowance for Loan Losses (Risk Portfolio Based on Payment Activity) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLossesTables</ParentRole>
      <Position>59</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>2402407 - Disclosure - Loans and the Allowance for Loan Losses (Age Analysis of Past Due Loans) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLossesAgeAnalysisOfPastDueLoansDetails</Role>
      <ShortName>Loans and the Allowance for Loan Losses (Age Analysis of Past Due Loans) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLossesTables</ParentRole>
      <Position>60</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>2402408 - Disclosure - Loans and the Allowance for Loan Losses (Impaired Loans) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLossesImpairedLoansDetails</Role>
      <ShortName>Loans and the Allowance for Loan Losses (Impaired Loans) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLossesTables</ParentRole>
      <Position>61</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>2402409 - Disclosure - Loans and the Allowance for Loan Losses (Recorded Investment for Impaired Loans) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLossesRecordedInvestmentForImpairedLoansDetails</Role>
      <ShortName>Loans and the Allowance for Loan Losses (Recorded Investment for Impaired Loans) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLossesTables</ParentRole>
      <Position>62</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>2402410 - Disclosure - Loans and the Allowance for Loan Losses (Troubled Debt Restructuring) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLossesTroubledDebtRestructuringDetails</Role>
      <ShortName>Loans and the Allowance for Loan Losses (Troubled Debt Restructuring) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLossesTables</ParentRole>
      <Position>63</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>2402411 - Disclosure - Loans and the Allowance for Loan Losses (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLossesDetailsTextual</Role>
      <ShortName>Loans and the Allowance for Loan Losses (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/LoansAndAllowanceForLoanLossesTables</ParentRole>
      <Position>64</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>2403402 - Disclosure - Premises and Equipment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/PremisesAndEquipmentDetails</Role>
      <ShortName>Premises and Equipment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/PremisesAndEquipmentTables</ParentRole>
      <Position>65</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>2403403 - Disclosure - Premises and Equipment (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/PremisesAndEquipmentDetailsTextual</Role>
      <ShortName>Premises and Equipment (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/PremisesAndEquipmentTables</ParentRole>
      <Position>66</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>2404402 - Disclosure - Deposits (Composition of Deposits) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/DepositsCompositionOfDepositsDetails</Role>
      <ShortName>Deposits (Composition of Deposits) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/DepositsTables</ParentRole>
      <Position>67</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>2404403 - Disclosure - Deposits (Scheduled Maturities) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/DepositsScheduledMaturitiesDetails</Role>
      <ShortName>Deposits (Scheduled Maturities) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/DepositsTables</ParentRole>
      <Position>68</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>2404404 - Disclosure - Deposits (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/DepositsDetailsTextual</Role>
      <ShortName>Deposits (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/DepositsTables</ParentRole>
      <Position>69</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>2405402 - Disclosure - Borrowings (Advances from FHLB) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/BorrowingsAdvancesFromFhlbDetails</Role>
      <ShortName>Borrowings (Advances from FHLB) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/BorrowingsTables</ParentRole>
      <Position>70</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>2405403 - Disclosure - Borrowings (Scheduled Maturity and Interest Rates for FHLB Advances) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/BorrowingsScheduledMaturityAndInterestRatesForFhlbAdvancesDetails</Role>
      <ShortName>Borrowings (Scheduled Maturity and Interest Rates for FHLB Advances) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/BorrowingsTables</ParentRole>
      <Position>71</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>2405404 - Disclosure - Borrowings (Repurchase Agreements and Fed Funds) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/BorrowingsRepurchaseAgreementsAndFedFundsDetails</Role>
      <ShortName>Borrowings (Repurchase Agreements and Fed Funds) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/BorrowingsTables</ParentRole>
      <Position>72</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>2405405 - Disclosure - Borrowings (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/BorrowingsDetailsTextual</Role>
      <ShortName>Borrowings (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/BorrowingsTables</ParentRole>
      <Position>73</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>2406402 - Disclosure - Income Taxes (Net Deferred Tax Assets) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/IncomeTaxesNetDeferredTaxAssetsDetails</Role>
      <ShortName>Income Taxes (Net Deferred Tax Assets) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/IncomeTaxesTables</ParentRole>
      <Position>74</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>2406403 - Disclosure - Income Taxes (Provision for Income Taxes) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/IncomeTaxesProvisionForIncomeTaxesDetails</Role>
      <ShortName>Income Taxes (Provision for Income Taxes) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/IncomeTaxesTables</ParentRole>
      <Position>75</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>2406404 - Disclosure - Income Taxes (Tax Rate Reconciliation) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/IncomeTaxesTaxRateReconciliationDetails</Role>
      <ShortName>Income Taxes (Tax Rate Reconciliation) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/IncomeTaxesTables</ParentRole>
      <Position>76</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>2406405 - Disclosure - Income Taxes (Narrative) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/IncomeTaxesNarrativeDetails</Role>
      <ShortName>Income Taxes (Narrative) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/IncomeTaxesTables</ParentRole>
      <Position>77</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>2407402 - Disclosure - Commitments and Contingent Liabilities (Operating Leases) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/CommitmentsAndContingentLiabilitiesOperatingLeasesDetails</Role>
      <ShortName>Commitments and Contingent Liabilities (Operating Leases) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/CommitmentsAndContingentLiabilitiesTables</ParentRole>
      <Position>78</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>2407403 - Disclosure - Commitments and Contingent Liabilities (Allowance for Losses on Mortgage Loans Sold) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/CommitmentsAndContingentLiabilitiesAllowanceForLossesOnMortgageLoansSoldDetails</Role>
      <ShortName>Commitments and Contingent Liabilities (Allowance for Losses on Mortgage Loans Sold) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/CommitmentsAndContingentLiabilitiesTables</ParentRole>
      <Position>79</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R80.htm</HtmlFileName>
      <LongName>2407404 - Disclosure - Commitments and Contingent Liabilities (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/CommitmentsAndContingentLiabilitiesDetailsTextual</Role>
      <ShortName>Commitments and Contingent Liabilities (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/CommitmentsAndContingentLiabilitiesTables</ParentRole>
      <Position>80</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R81.htm</HtmlFileName>
      <LongName>2408401 - Disclosure - Financial Instruments with Off-Balance-Sheet Risk (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/FinancialInstrumentsWithOffBalanceSheetRiskDetailsTextual</Role>
      <ShortName>Financial Instruments with Off-Balance-Sheet Risk (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/FinancialInstrumentsWithOffBalanceSheetRisk</ParentRole>
      <Position>81</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R82.htm</HtmlFileName>
      <LongName>2409401 - Disclosure - Related Party Transactions (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/RelatedPartyTransactionsDetailsTextual</Role>
      <ShortName>Related Party Transactions (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/RelatedPartyTransactions</ParentRole>
      <Position>82</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R83.htm</HtmlFileName>
      <LongName>2410402 - Disclosure - Share Based Compensation Plans (Changes in Stock Options Outstanding) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/ShareBasedCompensationPlansChangesInStockOptionsOutstandingDetails</Role>
      <ShortName>Share Based Compensation Plans (Changes in Stock Options Outstanding) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/ShareBasedCompensationPlansTables</ParentRole>
      <Position>83</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R84.htm</HtmlFileName>
      <LongName>2410403 - Disclosure - Share Based Compensation Plans (Options Outstanding, Range of Exercise Price) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/ShareBasedCompensationPlansOptionsOutstandingRangeOfExercisePriceDetails</Role>
      <ShortName>Share Based Compensation Plans (Options Outstanding, Range of Exercise Price) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/ShareBasedCompensationPlansTables</ParentRole>
      <Position>84</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R85.htm</HtmlFileName>
      <LongName>2410404 - Disclosure - Share Based Compensation Plans (Valuation Assumptions) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/ShareBasedCompensationPlansValuationAssumptionsDetails</Role>
      <ShortName>Share Based Compensation Plans (Valuation Assumptions) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/ShareBasedCompensationPlansTables</ParentRole>
      <Position>85</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R86.htm</HtmlFileName>
      <LongName>2410405 - Disclosure - Share Based Compensation Plans (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/ShareBasedCompensationPlansDetailsTextual</Role>
      <ShortName>Share Based Compensation Plans (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/ShareBasedCompensationPlansTables</ParentRole>
      <Position>86</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R87.htm</HtmlFileName>
      <LongName>2411402 - Disclosure - Capital Requirements (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/CapitalRequirementsDetails</Role>
      <ShortName>Capital Requirements (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/CapitalRequirementsTables</ParentRole>
      <Position>87</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R88.htm</HtmlFileName>
      <LongName>2412402 - 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>88</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R89.htm</HtmlFileName>
      <LongName>2413401 - Disclosure - Employee Benefits (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/EmployeeBenefitsDetailsTextual</Role>
      <ShortName>Employee Benefits (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/EmployeeBenefits</ParentRole>
      <Position>89</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R90.htm</HtmlFileName>
      <LongName>2414402 - Disclosure - Other Expenses (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/OtherExpensesDetails</Role>
      <ShortName>Other Expenses (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>90</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R91.htm</HtmlFileName>
      <LongName>2414403 - Disclosure - Other Income and Other Operating Expenses Other Income (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/OtherIncomeAndOtherOperatingExpensesOtherIncomeDetails</Role>
      <ShortName>Other Income and Other Operating Expenses Other Income (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>91</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R92.htm</HtmlFileName>
      <LongName>2415402 - Disclosure - Fair Value Measurements (Assets and Liabilities Measured at Fair Value) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/FairValueMeasurementsAssetsAndLiabilitiesMeasuredAtFairValueDetails</Role>
      <ShortName>Fair Value Measurements (Assets and Liabilities Measured at Fair Value) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/FairValueMeasurementsTables</ParentRole>
      <Position>92</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R93.htm</HtmlFileName>
      <LongName>2415403 - Disclosure - Fair Value Measurements (Level 3 Assets and Liabilities, Recurring Basis) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/FairValueMeasurementsLevel3AssetsAndLiabilitiesRecurringBasisDetails</Role>
      <ShortName>Fair Value Measurements (Level 3 Assets and Liabilities, Recurring Basis) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/FairValueMeasurementsTables</ParentRole>
      <Position>93</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R94.htm</HtmlFileName>
      <LongName>2415404 - Disclosure - Fair Value Measurements (Level 3 Fair Value Measurements- Qualitative) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/FairValueMeasurementsLevel3FairValueMeasurementsQualitativeDetails</Role>
      <ShortName>Fair Value Measurements (Level 3 Fair Value Measurements- Qualitative) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/FairValueMeasurementsTables</ParentRole>
      <Position>94</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R95.htm</HtmlFileName>
      <LongName>2415405 - Disclosure - Fair Value Measurements (Fair Value, ASC 825-10) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/FairValueMeasurementsFairValueAsc82510Details</Role>
      <ShortName>Fair Value Measurements (Fair Value, ASC 825-10) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/FairValueMeasurementsTables</ParentRole>
      <Position>95</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R96.htm</HtmlFileName>
      <LongName>2415406 - Disclosure - Fair Value Measurements (Carrying Amounts and Estimated Fair Value) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/FairValueMeasurementsCarryingAmountsAndEstimatedFairValueDetails</Role>
      <ShortName>Fair Value Measurements (Carrying Amounts and Estimated Fair Value) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/FairValueMeasurementsTables</ParentRole>
      <Position>96</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R97.htm</HtmlFileName>
      <LongName>2416402 - Disclosure - Parent Corporation Only Statements (Balance Sheet)  (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/ParentCorporationOnlyStatementsBalanceSheetDetails</Role>
      <ShortName>Parent Corporation Only Statements (Balance Sheet)  (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/ParentCorporationOnlyStatementsTables</ParentRole>
      <Position>97</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R98.htm</HtmlFileName>
      <LongName>2416402 - 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>98</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R99.htm</HtmlFileName>
      <LongName>2416403 - Disclosure - Parent Corporation Only Statements (Statement of Income) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/ParentCorporationOnlyStatementsStatementOfIncomeDetails</Role>
      <ShortName>Parent Corporation Only Statements (Statement of Income) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/ParentCorporationOnlyStatementsTables</ParentRole>
      <Position>99</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R100.htm</HtmlFileName>
      <LongName>2416404 - Disclosure - Parent Corporation Only Statements (Statements of Comprehensive Income) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/ParentCorporationOnlyStatementsStatementsOfComprehensiveIncomeDetails</Role>
      <ShortName>Parent Corporation Only Statements (Statements of Comprehensive Income) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/ParentCorporationOnlyStatementsTables</ParentRole>
      <Position>100</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R101.htm</HtmlFileName>
      <LongName>2416405 - Disclosure - Parent Corporation Only Statements (Statement of Cash Flows) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/ParentCorporationOnlyStatementsStatementOfCashFlowsDetails</Role>
      <ShortName>Parent Corporation Only Statements (Statement of Cash Flows) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/ParentCorporationOnlyStatementsTables</ParentRole>
      <Position>101</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R102.htm</HtmlFileName>
      <LongName>2417402 - 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>102</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R103.htm</HtmlFileName>
      <LongName>2417403 - 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>103</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R104.htm</HtmlFileName>
      <LongName>2417404 - 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>104</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R105.htm</HtmlFileName>
      <LongName>2417405 - Disclosure - Goodwill and Intangible Assets - Summary of Expected Intangible Amortization (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/GoodwillAndIntangibleAssetsSummaryOfExpectedIntangibleAmortizationDetails</Role>
      <ShortName>Goodwill and Intangible Assets - Summary of Expected Intangible Amortization (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>105</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R106.htm</HtmlFileName>
      <LongName>2418401 - Disclosure - Bank-Owned Life Insurance (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/BankOwnedLifeInsuranceDetailsTextual</Role>
      <ShortName>Bank-Owned Life Insurance (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.accessnationalbank.com/role/BankOwnedLifeInsurance</ParentRole>
      <Position>106</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R107.htm</HtmlFileName>
      <LongName>2419402 - 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>107</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R108.htm</HtmlFileName>
      <LongName>2419403 - 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>108</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R109.htm</HtmlFileName>
      <LongName>2419404 - 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>109</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R110.htm</HtmlFileName>
      <LongName>2419405 - 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>110</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R111.htm</HtmlFileName>
      <LongName>2420402 - Disclosure - Merger with Middleburg Financial Corporation - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/MergerWithMiddleburgFinancialCorporationNarrativeDetails</Role>
      <ShortName>Merger with Middleburg Financial Corporation - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>111</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R112.htm</HtmlFileName>
      <LongName>2420403 - Disclosure - Merger with Middleburg Financial Corporation - Schedule of Fair Value of Identifiable Assets Acquired and Liabilities Assumed (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/MergerWithMiddleburgFinancialCorporationScheduleOfFairValueOfIdentifiableAssetsAcquiredAndLiabilitiesAssumedDetails</Role>
      <ShortName>Merger with Middleburg Financial Corporation - Schedule of Fair Value of Identifiable Assets Acquired and Liabilities Assumed (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>112</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R113.htm</HtmlFileName>
      <LongName>2420404 - Disclosure - Merger with Middleburg Financial Corporation - Loans Identified as Impaired at Acquisition Date (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/MergerWithMiddleburgFinancialCorporationLoansIdentifiedAsImpairedAtAcquisitionDateDetails</Role>
      <ShortName>Merger with Middleburg Financial Corporation - Loans Identified as Impaired at Acquisition Date (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>113</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R114.htm</HtmlFileName>
      <LongName>2420405 - Disclosure - Merger with Middleburg Financial Corporation - Pro Forma Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.accessnationalbank.com/role/MergerWithMiddleburgFinancialCorporationProFormaInformationDetails</Role>
      <ShortName>Merger with Middleburg Financial Corporation - Pro Forma Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>114</Position>
    </Report>
    <Report instance="ancx-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9999.htm</HtmlFileName>
      <LongName>Uncategorized Items - ancx-20171231.xml</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/role/uncategorizedFacts</Role>
      <ShortName>Uncategorized Items - ancx-20171231.xml</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>115</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-20171231.xml</File>
    <File>ancx-20171231.xsd</File>
    <File>ancx-20171231_cal.xml</File>
    <File>ancx-20171231_def.xml</File>
    <File>ancx-20171231_lab.xml</File>
    <File>ancx-20171231_pre.xml</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy>http://fasb.org/us-gaap/2017-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://xbrl.sec.gov/invest/2013-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://xbrl.sec.gov/dei/2014-01-31</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
