XML 62 R49.htm IDEA: XBRL DOCUMENT
v3.25.3

Note 7 - Loans and Related Allowance for Credit Losses - Primary Segments of the Loan Portfolio (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Jun. 30, 2025 | Dec. 31, 2024 | Sep. 30, 2024 | Jun. 30, 2024 | Dec. 31, 2023
--- | --- | --- | --- | --- | --- | ---
Loans | [2],[3] | $ 1,607,024 | [1],[4] |  | $ 1,519,614 |  |  |  |
Less: Allowance for credit losses |  | (23,029) | [1],[2],[3],[4] | $ (22,335) | (22,447) | [2],[3] | $ (22,526) | $ (21,795) | $ (21,693)
Net loans | [2],[3] | 1,583,995 | [1],[4] |  | 1,497,167 |  |  |  |
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] |  |  |  |  |  |  |  |  |
Loans | [2],[3] | 221,600 | [1],[4] |  | 181,447 |  |  |  |
Less: Allowance for credit losses |  | (2,941) |  | (2,538) | (2,100) |  | (2,190) | (2,058) | (2,668)
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] |  |  |  |  |  |  |  |  |
Loans | [2],[3] | 390,354 | [1],[4] |  | 412,291 |  |  |  |
Less: Allowance for credit losses |  | (4,919) |  | (4,628) | (8,364) |  | (8,356) | (7,981) | (4,480)
Commercial Real Estate Portfolio Segment [Member] | Multifamily Loan [Member] |  |  |  |  |  |  |  |  |
Loans | [2],[3] | 88,899 | [1],[4] |  | 89,849 |  |  |  |
Less: Allowance for credit losses |  | (1,164) |  | (1,057) | (1,310) |  | (1,393) | (1,268) | (1,796)
Residential Portfolio Segment [Member] |  |  |  |  |  |  |  |  |
Loans | [2],[3] | 366,307 | [1],[4] |  | 353,442 |  |  |  |
Less: Allowance for credit losses |  | (5,989) |  | (5,801) | (5,236) |  | (5,110) | (4,891) | (5,450)
Commercial And Industrial [Member] |  |  |  |  |  |  |  |  |
Loans | [2],[3] | 269,422 | [1],[4] |  | 229,034 |  |  |  |
Less: Allowance for credit losses |  | (3,426) |  | (3,014) | (2,427) |  | (2,412) | (2,430) | (4,377)
Home Equity Lines of Credit [Member] |  |  |  |  |  |  |  |  |
Loans | [2],[3] | 159,805 | [1],[4] |  | 143,379 |  |  |  |
Less: Allowance for credit losses |  | (1,007) |  | (988) | (897) |  | (869) | (813) | (750)
Construction and Other [Member] |  |  |  |  |  |  |  |  |
Loans | [2],[3] | 104,843 | [1],[4] |  | 103,608 |  |  |  |
Less: Allowance for credit losses |  | (3,513) |  | (4,234) | (2,052) |  | (2,131) | (2,290) | (1,990)
Consumer Portfolio Segment [Member] |  |  |  |  |  |  |  |  |
Loans | [2],[3] | 5,794 | [1],[4] |  | 6,564 |  |  |  |
Less: Allowance for credit losses |  | $ (70) |  | $ (75) | $ (61) |  | $ (65) | $ (64) | $ (182)
[1] | Accrued interest of $5.5 million and $5.5 million at June 30, 2025 and December 31, 2024, respectively, is excluded from amortized cost and presented in "accrued interest receivable and other assets" on the Consolidated Balance Sheets.
[2] | Accrued interest of $5.9 million and $5.5 million at September 30, 2025 and December 31, 2024, respectively, is excluded from amortized cost and presented in "accrued interest receivable and other assets" on the Consolidated Balance Sheets.
[3] | Unearned income, including net deferred loan fees and costs and unamortized premiums and discounts, totaled $6.6 million and $8.2 million at September 30, 2025 and December 31, 2024, respectively.
[4] | Unearned income, including net deferred loan fees and costs and unamortized premiums and discounts, totaled $7.1 million and $8.2 million at June 30, 2025 and December 31, 2024, respectively.

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 -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 + 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, after allowance for credit loss, of financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-5 + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

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

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

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

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

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=mbcn_ConstructionAndOtherMember
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: |