Amount of Federal Home Loan Bank (FHLBank) advances to member financial institutions

No definition available.

Name:	botj_AdditionalFederalHomeLoanBankAdvances
Namespace Prefix:	botj_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Debt Instrument Principal Balance

+ References

No definition available.

+ Details

Name:	botj_DebtInstrumentPrincipalBalance
Namespace Prefix:	botj_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line Of Credit Unsecured Federal Funds

+ References

No definition available.

+ Details

Name:	botj_LineOfCreditUnsecuredFederalFunds
Namespace Prefix:	botj_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Number of equal monthly installments of principal and interest.

+ References

No definition available.

+ Details

Name:	botj_NumberOfEqualMonthlyInstallmentsOfPrincipalAndInterest
Namespace Prefix:	botj_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of capital stock purchased

+ References

No definition available.

+ Details

Name:	botj_PercentageOfCapitalStockPurchased
Namespace Prefix:	botj_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of common stock secured by first priority lien.

+ References

No definition available.

+ Details

Name:	botj_PercentageOfCommonStockSecuredByFirstPriorityLien
Namespace Prefix:	botj_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Short-Term Debt, Average Daily Outstanding Amount

+ References

No definition available.

+ Details

Name:	botj_ShortTermDebtAverageDailyOutstandingAmount
Namespace Prefix:	botj_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Unsecured Federal Funds Outstanding Amount

+ References

No definition available.

+ Details

Name:	botj_UnsecuredFederalFundsOutstandingAmount
Namespace Prefix:	botj_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(a)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of the required periodic payments including both interest and principal payments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477734/942-470-50-3

+ Details

Name:	us-gaap_DebtInstrumentPeriodicPayment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of Federal Home Loan Bank (FHLBank) advances to member financial institutions.

+ References

No definition available.

+ Details

Name:	us-gaap_FederalHomeLoanBankAdvances
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of borrowings classified as other, maturing within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(a)(7))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-04(13)(a)(4))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479170/946-210-S99-1

+ Details

Name:	us-gaap_OtherShortTermBorrowings
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash inflow from Federal Home Loan Bank (FHLBank) borrowing, classified as financing activity.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-14

+ Details

Name:	us-gaap_ProceedsFromFederalHomeLoanBankBorrowings
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

+ Details

Name:	us-gaap_ProceedsFromIssuanceOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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.

+ References

No definition available.

+ Details

Name:	us-gaap_ShortTermDebtLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=botj_PettyjohnWoodWhiteIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=botj_NationalBankOfBlacksburgMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=botj_CommunityBankersBankMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=botj_FhlbaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

Other Borrowings (Narrative) (Details)			12 Months Ended
Other Borrowings (Narrative) (Details)	Sep. 30, 2025 USD ($)	Dec. 29, 2021 USD ($)	Dec. 31, 2025 USD ($) item	Dec. 31, 2024 USD ($)	Jun. 30, 2022
Short-term Debt [Line Items]
Short-term Borrowings			$ 0
Unsecured federal fund lines			58,000,000
FHLBA additional credit			47,574,000
Borrowed amount from FHLBA			$ 60,959,000
Number of equal monthly installments of principal and interest \| item			60
Unsecured Federal Funds Outstanding Amount			$ 0	$ 0
Pettyjohn, Wood & White, Inc [Member]
Short-term Debt [Line Items]
Percentage of capital stock purchased			100.00%
National Bank of Blacksburg (NBB Note) [Member]
Short-term Debt [Line Items]
Proceeds from Issuance of Debt		$ 11,000,000
Debt instrument, interest rate, stated percentage	5.65%	4.00%			3.90%
Debt monthly installments of principal and interest	$ 61,805.22
Percentage of common stock secured by first priority lien			4.95%
Capital notes, principal balance			$ 8,796,000	$ 9,300,000
Community Bankers Bank [Member]
Short-term Debt [Line Items]
Available credit			5,117,000
FHLBA [Member]
Short-term Debt [Line Items]
Available credit			303,408,000
Maximum [Member]
Short-term Debt [Line Items]
Average daily balances			$ 1,100