XML 81 R69.htm IDEA: XBRL DOCUMENT
v3.22.4

Loans and Allowance for Credit Losses - Schedule of Collateral-Dependent Non-Accrual Loans (Details) - USD ($) | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Sep. 30, 2020
--- | --- | --- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans | $ 2,432,000 | $ 8,376,000 |  |
Allowance for credit losses on loans | $ 22,983,000 | $ 23,023,000 | $ 22,874,000 | $ 22,113,000
Weighted average ratio of loans value to collateral dependent loans value | 42.00% | 67.00% |  |
Collateral Pledged |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans | $ 2,432,000 | $ 8,376,000 |  |
Allowance for credit losses on loans | 0 | 0 |  |
Commercial Real Estate |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans | 1,563,000 | 7,963,000 |  |
Residential Real Estate |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans | 778,000 | 413,000 |  |
Other |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans | 91,000 | 0 |  |
Commercial real estate | Commercial owner-occupied |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans | 1,563,000 | 7,269,000 |  |
Allowance for credit losses on loans | 2,487,000 | 2,776,000 | 2,778,000 | 3,135,000
Commercial real estate | Commercial owner-occupied | Collateral Pledged |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans | 1,563,000 | 7,269,000 |  |
Allowance for credit losses on loans | 0 | 0 |  |
Commercial real estate | Commercial owner-occupied | Commercial Real Estate |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans | 1,563,000 | 7,269,000 |  |
Commercial real estate | Commercial owner-occupied | Residential Real Estate |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans | 0 | 0 |  |
Commercial real estate | Commercial owner-occupied | Other |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans | 0 | 0 |  |
Commercial real estate | Commercial investor-owned |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans | 0 | 694,000 |  |
Allowance for credit losses on loans | 12,676,000 | 12,739,000 | 12,682,000 | 11,624,000
Commercial real estate | Commercial investor-owned | Collateral Pledged |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans |  | 694,000 |  |
Allowance for credit losses on loans |  | 0 |  |
Commercial real estate | Commercial investor-owned | Commercial Real Estate |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans |  | 694,000 |  |
Commercial real estate | Commercial investor-owned | Residential Real Estate |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans |  | 0 |  |
Commercial real estate | Commercial investor-owned | Other |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans |  | 0 |  |
Commercial real estate | Installment and other consumer loans | Collateral Pledged |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans | 91,000 |  |  |
Allowance for credit losses on loans | 0 |  |  |
Commercial real estate | Installment and other consumer loans | Commercial Real Estate |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans | 0 |  |  |
Commercial real estate | Installment and other consumer loans | Residential Real Estate |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans | 0 |  |  |
Commercial real estate | Installment and other consumer loans | Other |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans | 91,000 |  |  |
Residential loans | Home equity |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans | 778,000 | 413,000 |  |
Allowance for credit losses on loans | 558,000 | 595,000 | 738,000 | 1,038,000
Residential loans | Home equity | Collateral Pledged |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans | 778,000 | 413,000 |  |
Allowance for credit losses on loans | 0 | 0 |  |
Residential loans | Home equity | Commercial Real Estate |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans | 0 | 0 |  |
Residential loans | Home equity | Residential Real Estate |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans | 778,000 | 413,000 |  |
Residential loans | Home equity | Other |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans | 0 | 0 |  |
Residential loans | Other residential |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-accrual loans | 0 | 0 |  |
Allowance for credit losses on loans | 595,000 | 644,000 | $ 998,000 | $ 1,260,000
Residential loans | Other residential | Collateral Pledged |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Nonaccrual collateral dependent loans in process of foreclosure | $ 0 | $ 0 |  |

X
- Definition Financing Receivable, Nonaccrual, In Process Of Foreclosure + References No definition available. + Details
Name: | bmrc_FinancingReceivableNonaccrualInProcessOfForeclosure
Namespace Prefix: | bmrc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Weighted Average Ratio Of Loans Value To Collateral Dependent Loans Value + References No definition available. + Details
Name: | bmrc_WeightedAverageRatioOfLoansValueToCollateralDependentLoansValue
Namespace Prefix: | bmrc_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- 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_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446 + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amortized cost excluding accrued interest, of financing receivable on nonaccrual status. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 16 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447 + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrual
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_CollateralAxis=us-gaap_CollateralPledgedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CollateralAxis=us-gaap_CommercialRealEstateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CollateralAxis=us-gaap_ResidentialRealEstateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CollateralAxis=bmrc_OtherCollateralHeldMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialRealEstatePortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=bmrc_CommercialRealEstateLoanOwnerOccupiedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=bmrc_CommercialRealEstateLoanInvestorMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=bmrc_InstallmentAndOtherConsumerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_HomeEquityLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=bmrc_OtherResidentialLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |