XML 24 R28.htm IDEA: XBRL DOCUMENT
v3.2.0.727

Fair Value of Assets and Liabilities - Fair Value of Financial Instruments (Details) $ in Thousands | 6 Months Ended |
--- | --- | ---
Jun. 30, 2015 USD ($) debenture | Dec. 31, 2014 USD ($)
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] |  |
Investment securities held to maturity | $ 96,017 | $ 118,643
Subordinated Debt [Abstract] |  |
Number of subordinated debentures acquired | debenture | 2 |
Subordinated debenture |  |
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract] |  |
Subordinated debentures | $ 4,950 |
Subordinated Debt [Abstract] |  |
Number of subordinated debentures acquired | debenture | 2 |
NorCal Community Bancorp Trust I | Subordinated debenture |  |
Subordinated Debt [Abstract] |  |
Basis spread on subordinated debentures | 3.05% |
NorCal Community Bancorp Trust II | Subordinated debenture |  |
Subordinated Debt [Abstract] |  |
Basis spread on subordinated debentures | 1.40% |
Carrying Value | Fair Value Hierarchy, Level 1 |  |
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] |  |
Cash and cash equivalents | $ 117,533 | 41,367
Carrying Value | Fair Value Hierarchy, Level 2 |  |
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] |  |
Investment securities held to maturity | 94,475 | 116,437
Interest receivable | 5,800 | 5,909
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract] |  |
Deposits | 1,630,483 | 1,551,619
Federal Home Loan Bank borrowings | 15,000 | 15,000
Interest payable | 209 | 213
Carrying Value | Fair Value Hierarchy, Level 3 |  |
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] |  |
Loans, net | 1,324,851 | 1,348,252
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract] |  |
Subordinated debentures | 5,291 | 5,185
Fair Value | Fair Value Hierarchy, Level 1 |  |
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] |  |
Cash and cash equivalents | 117,533 | 41,367
Fair Value | Fair Value Hierarchy, Level 2 |  |
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] |  |
Investment securities held to maturity | 96,017 | 118,643
Interest receivable | 5,800 | 5,909
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract] |  |
Deposits | 1,631,106 | 1,552,446
Federal Home Loan Bank borrowings | 15,445 | 15,484
Interest payable | 209 | 213
Fair Value | Fair Value Hierarchy, Level 3 |  |
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] |  |
Loans, net | 1,332,708 | 1,361,244
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract] |  |
Subordinated debentures | $ 5,192 | $ 5,290

X
- Definition Business Combinations, Number of Debt Instruments Acquired + References No definition available. + Details
Name: | bmrc_BusinessCombinationsNumberofDebtInstrumentsAcquired
Namespace Prefix: | bmrc_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition This element represents the disclosures for fair value estimates for financial instruments required in the footnote disclosures to the financial statements. Carrying amount reprsents accrued interest payable on all forms of debt, including deposit liabilities, that has been incurred and is unpaid for time value of money. The carrying value may approximate fair value due to the short-term nature of their settlement dates. + References No definition available. + Details
Name: | bmrc_InterestPayableFairValueDisclosure
Namespace Prefix: | bmrc_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition This element represents the disclosures for fair value estimates for financial instruments required in the footnote disclosures to the financial statements. Carrying amount represents interest earned but not received from loan borrowers, investment security issuers and on other forms of short-term investment for time value of money. The carrying value may approximate fair value due to the short-term nature of their settlement dates. + References No definition available. + Details
Name: | bmrc_InterestReceivableFairValueDisclosure
Namespace Prefix: | bmrc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash -URI http://asc.fasb.org/extlink&oid=6506951 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash Equivalents -URI http://asc.fasb.org/extlink&oid=6507016 + Details
Name: | us-gaap_CashAndCashEquivalentsFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits. + References No definition available. + Details
Name: | us-gaap_DepositsFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a),(b) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Fair value portion of borrowing from Federal Home Loan Bank (FHLBank). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.13(3)(a)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
Name: | us-gaap_FederalHomeLoanBankBorrowingsFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Fair value of investments in debt securities classified as held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 + Details
Name: | us-gaap_HeldToMaturitySecuritiesFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Glossary Loan -URI http://asc.fasb.org/extlink&oid=6517073 + Details
Name: | us-gaap_LoansReceivableFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_SubordinatedLongtermDebtCurrentAndNoncurrentAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=us-gaap_SubordinatedDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=bmrc_NorCalCommunityBancorpTrustIMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=bmrc_NorCalCommunityBancorpTrustIIMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByMeasurementBasisAxis=us-gaap_CarryingReportedAmountFairValueDisclosureMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel1Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel2Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByMeasurementBasisAxis=us-gaap_EstimateOfFairValueFairValueDisclosureMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |