Note 3 - Loans (Details) (USD $)	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012
Note 3 - Loans (Details) [Line Items]
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans (in Dollars)	$ 11,000	$ 93,000
Principal Reduction, Percentage	72.00%
Consumer Loans [Member] \| Minimum [Member]
Note 3 - Loans (Details) [Line Items]
Amortization Period	12 months
Consumer Loans [Member] \| Maximum [Member]
Note 3 - Loans (Details) [Line Items]
Amortization Period	60 months
MetroBank [Member] \| Minimum [Member]
Note 3 - Loans (Details) [Line Items]
Amortization Period	15 years
Balloon Payment Period	five
MetroBank [Member] \| Maximum [Member]
Note 3 - Loans (Details) [Line Items]
Amortization Period	20 years
Balloon Payment Period	seven
Metro United [Member] \| Minimum [Member]
Note 3 - Loans (Details) [Line Items]
Amortization Period	25 years
Balloon Payment Period	five
Metro United [Member] \| Maximum [Member]
Note 3 - Loans (Details) [Line Items]
Amortization Period	30 years
Balloon Payment Period	ten
MetroBank Maximum [Member]
Note 3 - Loans (Details) [Line Items]
Loans and Leases Receivable, Gross (in Dollars)	13,000,000
Metro United Maximum [Member]
Note 3 - Loans (Details) [Line Items]
Loans and Leases Receivable, Gross (in Dollars)	$ 8,000,000
Minimum [Member]
Note 3 - Loans (Details) [Line Items]
Amortization Period	15 years
Balloon Payment Period	two
Maximum [Member]
Note 3 - Loans (Details) [Line Items]
Amortization Period	30 years
Balloon Payment Period	seven

The amount of time required to pay off a loan.

No definition available.

Name:	mcbi_AmortizationPeriod
Namespace Prefix:	mcbi_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

The term of a loan which does not fully amortize, thus leaving a balance due at maturity.

+ References

No definition available.

+ Details

Name:	mcbi_BalloonPaymentPeriod
Namespace Prefix:	mcbi_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	mcbi_Note3LoansDetailsLineItems
Namespace Prefix:	mcbi_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Principal reduction, percentage.

+ References

No definition available.

+ Details

Name:	mcbi_PrincipalReductionPercentage
Namespace Prefix:	mcbi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

+ Details

Name:	us-gaap_LoansAndLeasesReceivableGrossCarryingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18794-111554

+ Details

Name:	us-gaap_LoansAndLeasesReceivableImpairedInterestLostOnNonaccrualLoans
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration