XML 56 R47.htm IDEA: XBRL DOCUMENT
v3.22.1

Loans and Allowance for Credit Losses on Loans - Allowance for Credit Losses on Loans (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2022 | Dec. 31, 2021 | Mar. 31, 2021
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Beginning balance | $ 23,023 |  | $ 22,874
Provision (reversal) | (485) | $ 600 | (2,929)
Charge-offs | (2) |  | 0
Recoveries | 11 |  | 13
Ending balance | 22,547 | 23,023 | 19,958
Commercial loans | Commercial and industrial |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Beginning balance | 1,709 |  | 2,530
Provision (reversal) | 72 |  | (880)
Charge-offs | 0 |  | 0
Recoveries | 3 |  | 4
Ending balance | 1,784 | 1,709 | 1,654
Commercial real estate loans | Commercial owner-occupied |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Beginning balance | 2,776 |  | 2,778
Provision (reversal) | (154) |  | (474)
Charge-offs | 0 |  | 0
Recoveries | 0 |  | 0
Ending balance | 2,622 | 2,776 | 2,304
Commercial real estate loans | Commercial investor-owned |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Beginning balance | 12,739 |  | 12,682
Provision (reversal) | (438) |  | (1,826)
Charge-offs | 0 |  | 0
Recoveries | 0 |  | 0
Ending balance | 12,301 | 12,739 | 10,856
Commercial real estate loans | Construction |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Beginning balance | 1,653 |  | 1,557
Provision (reversal) | 56 |  | (254)
Charge-offs | 0 |  | 0
Recoveries | 8 |  | 9
Ending balance | 1,717 | 1,653 | 1,312
Residential loans | Home equity |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Beginning balance | 595 |  | 738
Provision (reversal) | (46) |  | (218)
Charge-offs | 0 |  | 0
Recoveries | 0 |  | 0
Ending balance | 549 | 595 | 520
Residential loans | Other residential |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Beginning balance | 644 |  | 998
Provision (reversal) | (16) |  | (241)
Charge-offs | 0 |  | 0
Recoveries | 0 |  | 0
Ending balance | 628 | 644 | 757
Consumer loans | Installment and other consumer loans |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Beginning balance | 621 |  | 291
Provision (reversal) | 22 |  | (36)
Charge-offs | (2) |  | 0
Recoveries | 0 |  | 0
Ending balance | 641 | 621 | 255
Unallocated |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |
Beginning balance | 2,286 |  | 1,300
Provision (reversal) | 19 |  | 1,000
Charge-offs | 0 |  | 0
Recoveries | 0 |  | 0
Ending balance | $ 2,305 | $ 2,286 | $ 2,300

X
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
Name: | us-gaap_AllowanceForLoanAndLeaseLossesRollForward
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. + 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 http://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 Amount of increase in allowance for credit loss on financing receivable from recovery. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 55 -Paragraph 79 -URI http://asc.fasb.org/extlink&oid=124267575&loc=SL82922352-210448 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(4) -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524 + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of writeoff of financing receivable, charged against allowance for credit loss. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 55 -Paragraph 79 -URI http://asc.fasb.org/extlink&oid=124267575&loc=SL82922352-210448 + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of credit loss expense (reversal of expense) for financing receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(11)) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 + Details
Name: | us-gaap_ProvisionForLoanLossesExpensed
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=bmrc_CommercialAndIndustrialMember
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=us-gaap_ConstructionLoansMember
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: |

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