XML 28 R28.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Note 4 - Fair Value Measurements (Details) - Assets Measured on a Recurring Basis (USD $) In Thousands, unless otherwise specified | Mar. 31, 2015 | Dec. 31, 2014
--- | --- | ---
Assets measured on a recurring basis: |  |
Investment securities available for sale, at fair value | $ 151,159 us-gaap_AvailableForSaleSecurities | $ 154,334 us-gaap_AvailableForSaleSecurities
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Assets measured on a recurring basis: |  |
Investment securities available for sale, at fair value | 22,921 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember | 22,896 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember
US Government Agencies Debt Securities [Member] |  |
Assets measured on a recurring basis: |  |
Investment securities available for sale, at fair value | 22,921 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember | 22,896 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USGovernmentAgenciesDebtSecuritiesMember
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Assets measured on a recurring basis: |  |
Investment securities available for sale, at fair value | 96,097 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember | 98,345 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember
US States and Political Subdivisions Debt Securities [Member] |  |
Assets measured on a recurring basis: |  |
Investment securities available for sale, at fair value | 96,097 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember | 98,345 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Assets measured on a recurring basis: |  |
Investment securities available for sale, at fair value | 28,517 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember | 29,391 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Assets measured on a recurring basis: |  |
Investment securities available for sale, at fair value | 28,517 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember | 29,391 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember
Mortgage-backed Securities, Issued by Private Enterprises [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Assets measured on a recurring basis: |  |
Investment securities available for sale, at fair value | 2,725 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember | 2,919 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
Mortgage-backed Securities, Issued by Private Enterprises [Member] |  |
Assets measured on a recurring basis: |  |
Investment securities available for sale, at fair value | 2,725 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember | 2,919 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Assets measured on a recurring basis: |  |
Investment securities available for sale, at fair value | 150,260 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_DebtSecuritiesMember | 153,551 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_DebtSecuritiesMember
Debt Securities [Member] |  |
Assets measured on a recurring basis: |  |
Investment securities available for sale, at fair value | 150,260 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_DebtSecuritiesMember | 153,551 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_DebtSecuritiesMember
Equity Securities in Financial Institutions [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Assets measured on a recurring basis: |  |
Investment securities available for sale, at fair value | 899 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = mbcn_EquitySecuritiesInFinancialInstitutionsMember | 783 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = mbcn_EquitySecuritiesInFinancialInstitutionsMember
Equity Securities in Financial Institutions [Member] |  |
Assets measured on a recurring basis: |  |
Investment securities available for sale, at fair value | 899 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = mbcn_EquitySecuritiesInFinancialInstitutionsMember | 783 us-gaap_AvailableForSaleSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = mbcn_EquitySecuritiesInFinancialInstitutionsMember
Fair Value, Inputs, Level 2 [Member] |  |
Assets measured on a recurring basis: |  |
Investment securities available for sale, at fair value | $ 151,159 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | $ 154,334 us-gaap_AvailableForSaleSecurities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member

X
- Details
Name: | mbcn_AssetsMeasuredOnARecurringBasisAbstract0
Namespace Prefix: | mbcn_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 2: 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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 + Details
Name: | us-gaap_AvailableForSaleSecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=mbcn_EquitySecuritiesInFinancialInstitutionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_DebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_USGovernmentAgenciesDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_USStatesAndPoliticalSubdivisionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |