<?xml version="1.0" encoding="utf-8"?>
<FilingSummary xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <Version>2.4.0.6</Version>
  <ProcessingTime />
  <ReportFormat>Html</ReportFormat>
  <ContextCount>46</ContextCount>
  <ElementCount>181</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>6</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>3</UnitCount>
  <MyReports>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>00090 - Document - Document And Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/DocumentDocumentAndEntityInformation</Role>
      <ShortName>Document And Entity Information</ShortName>
    </Report>
    <Report>
      <IsDefault>true</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>00100 - Statement - Consolidated Balance Sheets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/StatementConsolidatedBalanceSheets</Role>
      <ShortName>Consolidated Balance Sheets</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>00105 - Statement - Consolidated Balance Sheets (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/StatementConsolidatedBalanceSheetsParenthetical</Role>
      <ShortName>Consolidated Balance Sheets (Parenthetical)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>00200 - Statement - Consolidated Statements Of Income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/StatementConsolidatedStatementsOfIncome</Role>
      <ShortName>Consolidated Statements Of Income</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>00300 - Statement - Consolidated Statements Of Changes In Shareholders' Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/StatementConsolidatedStatementsOfChangesInShareholdersEquity</Role>
      <ShortName>Consolidated Statements Of Changes In Shareholders' Equity</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>00305 - Statement - Consolidated Statements Of Changes In Shareholders' Equity (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/StatementConsolidatedStatementsOfChangesInShareholdersEquityParenthetical</Role>
      <ShortName>Consolidated Statements Of Changes In Shareholders' Equity (Parenthetical)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>00400 - Statement - Consolidated Statements Of Comprehensive Income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/StatementConsolidatedStatementsOfComprehensiveIncome</Role>
      <ShortName>Consolidated Statements Of Comprehensive Income</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>00405 - Statement - Consolidated Statements Of Comprehensive Income (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/StatementConsolidatedStatementsOfComprehensiveIncomeParenthetical</Role>
      <ShortName>Consolidated Statements Of Comprehensive Income (Parenthetical)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>00500 - Statement - Consolidated Statements Of Cash Flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/StatementConsolidatedStatementsOfCashFlows</Role>
      <ShortName>Consolidated Statements Of Cash Flows</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>10101 - Disclosure - Summary Of Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/DisclosureSummaryOfSignificantAccountingPolicies</Role>
      <ShortName>Summary Of Significant Accounting Policies</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>10201 - Disclosure - Securities Available For Sale</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/DisclosureSecuritiesAvailableForSale</Role>
      <ShortName>Securities Available For Sale</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>10301 - Disclosure - Loans And Allowance For Loan Losses</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/DisclosureLoansAndAllowanceForLoanLosses</Role>
      <ShortName>Loans And Allowance For Loan Losses</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>10401 - Disclosure - Premises And Equipment</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/DisclosurePremisesAndEquipment</Role>
      <ShortName>Premises And Equipment</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>10501 - Disclosure - Goodwill And Other Intangible Assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/DisclosureGoodwillAndOtherIntangibleAssets</Role>
      <ShortName>Goodwill And Other Intangible Assets</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>10601 - Disclosure - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/DisclosureIncomeTaxes</Role>
      <ShortName>Income Taxes</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>10701 - Disclosure - Deposits</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/DisclosureDeposits</Role>
      <ShortName>Deposits</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>10801 - Disclosure - Short-Term Borrowings</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/DisclosureShortTermBorrowings</Role>
      <ShortName>Short-Term Borrowings</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>10901 - Disclosure - Long-Term Debt</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/DisclosureLongTermDebt</Role>
      <ShortName>Long-Term Debt</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>11001 - Disclosure - Shareholders' Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/DisclosureShareholdersEquity</Role>
      <ShortName>Shareholders' Equity</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>11101 - Disclosure - Stock-Based Compensation Plans</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/DisclosureStockBasedCompensationPlans</Role>
      <ShortName>Stock-Based Compensation Plans</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>11201 - Disclosure - Retirement Benefit Plans</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/DisclosureRetirementBenefitPlans</Role>
      <ShortName>Retirement Benefit Plans</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>11301 - Disclosure - Commitments And Contingent Liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/DisclosureCommitmentsAndContingentLiabilities</Role>
      <ShortName>Commitments And Contingent Liabilities</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>11401 - Disclosure - Fair Value Measurements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/DisclosureFairValueMeasurements</Role>
      <ShortName>Fair Value Measurements</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>11501 - Disclosure - Fair Value Of Financial Instruments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/DisclosureFairValueOfFinancialInstruments</Role>
      <ShortName>Fair Value Of Financial Instruments</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>11601 - Disclosure - Legal Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/DisclosureLegalContingencies</Role>
      <ShortName>Legal Contingencies</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>11701 - Disclosure - Condensed Financial Information - Parent Company Only</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/DisclosureCondensedFinancialInformationParentCompanyOnly</Role>
      <ShortName>Condensed Financial Information - Parent Company Only</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>11801 - Disclosure - Selected Quarterly Financial Data</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.bhbt.com/2011-03-31/role/DisclosureSelectedQuarterlyFinancialData</Role>
      <ShortName>Selected Quarterly Financial Data</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <Logs>
    <Log type="Info">Process Flow-Through: 00100 - Statement - Consolidated Balance Sheets</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Dec. 31, 2009'</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Dec. 31, 2008'</Log>
    <Log type="Info">Process Flow-Through: 00105 - Statement - Consolidated Balance Sheets (Parenthetical)</Log>
    <Log type="Info">Process Flow-Through: 00200 - Statement - Consolidated Statements Of Income</Log>
    <Log type="Info">Process Flow-Through: 00305 - Statement - Consolidated Statements Of Changes In Shareholders' Equity (Parenthetical)</Log>
    <Log type="Info">Process Flow-Through: 00400 - Statement - Consolidated Statements Of Comprehensive Income</Log>
    <Log type="Info">Process Flow-Through: 00405 - Statement - Consolidated Statements Of Comprehensive Income (Parenthetical)</Log>
    <Log type="Info">Process Flow-Through: 00500 - Statement - Consolidated Statements Of Cash Flows</Log>
  </Logs>
  <InputFiles>
    <File>bhb-20111231.xml</File>
    <File>bhb-20111231.xsd</File>
    <File>bhb-20111231_cal.xml</File>
    <File>bhb-20111231_def.xml</File>
    <File>bhb-20111231_lab.xml</File>
    <File>bhb-20111231_pre.xml</File>
  </InputFiles>
  <SupplementalFiles />
  <BaseTaxonomies />
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
