Name:	bhb_EmployeeBenefitPlan.CatchUpContributionEligibilityAge
Namespace Prefix:	bhb_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

Represents the minimum age criteria for plan eligibility under employee benefit plan.

No definition available.

Name:	bhb_EmployeeBenefitPlanMinimumAgeForPlanEligibility
Namespace Prefix:	bhb_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

Represents the minimum service period for plan eligibility under employee benefit plan EBP.

No definition available.

Name:	bhb_EmployeeBenefitPlanMinimumServicePeriodForPlanEligibility
Namespace Prefix:	bhb_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Represents the percentage points added to the prime rate to compute the interest rate on participant loans.

No definition available.

Name:	bhb_EmployeeBenefitPlanNoteReceivableFromParticipantBasisSpreadOnPrimeRate
Namespace Prefix:	bhb_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Term of participant loan of employee stock purchase, saving, or similar plan employee benefit plan EBP.

No definition available.

Name:	bhb_EmployeeBenefitPlanNoteReceivableFromParticipantTerm
Namespace Prefix:	bhb_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Represents the participant age requirement for withdrawal from account balance of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

No definition available.

Name:	bhb_EmployeeBenefitPlanParticipantAgeForWithdrawalFromAccountBalance
Namespace Prefix:	bhb_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

Percentage increase in the automatic deferral rate applied annually to eligible compensation for participants automatically enrolled in an employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

No definition available.

Name:	bhb_EmployeeBenefitPlanParticipantAnnualContributionIncreaseRatePercentage
Namespace Prefix:	bhb_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Represents the percentage of vesting.

No definition available.

Name:	bhb_EmployeeBenefitPlanVestingPercentage
Namespace Prefix:	bhb_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Represents the percentage of vesting of participant accounts in the event of termination.

No definition available.

Name:	bhb_EmployeeBenefitPlanVestingPercentageInEventOfTermination
Namespace Prefix:	bhb_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

Name:	us-gaap-ebp_EmployeeBenefitPlanDescriptionOfPlanLineItems
Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Percentage of employer matching contribution on eligible participant contribution to employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

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Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Percentage of participant compensation eligible for employer matching contribution for participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

Name:	us-gaap-ebp_EmployeeBenefitPlanEmployerContributionParticipantCompensationMatchedPercentage
Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Amount of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

Name:	us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMaximumBorrowingAmount
Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Percentage of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow to total participant account balance.

Name:	us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMaximumBorrowingToTotalAccountPercentage
Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Percentage of eligible compensation contributed for participant automatically enrolled in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

Name:	us-gaap-ebp_EmployeeBenefitPlanParticipantContributionAutomaticDeferralRate
Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Percentage of maximum pretax annual compensation that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), is permitted to contribute to total pretax annual compensation.

Name:	us-gaap-ebp_EmployeeBenefitPlanParticipantContributionPretaxMaximumAnnualCompensationToTotalCompensationPercentage
Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Interest rate on participant loan in schedule of asset held for investment of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)(i)(D)
-Publisher DOL-EBSA

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule I))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

Name:	us-gaap-ebp_EmployeeBenefitPlanParticipantLoanInterestRate
Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Name:	dei_LegalEntityAxis=bhb_EBP002Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_StatementScenarioAxis=bhb_EmployeeBenefitPlanMatchingContributionFirstTierMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: