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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Amount of litigation reserve reversed.

No definition available.

Name:	mcb_LitigationReserveReversed
Namespace Prefix:	mcb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Loans and Leases Receivable, Commitments, Fixed Rates, Interest Rate Percentage

No definition available.

Name:	mcb_LoansAndLeasesReceivableCommitmentsFixedRatesInterestRatePercentage
Namespace Prefix:	mcb_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Represents the loans and leases receivable commitments pledged interest-bearing.

No definition available.

Name:	mcb_LoansAndLeasesReceivableCommitmentsPledged
Namespace Prefix:	mcb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Loans and Leases Receivable, Commitments, variable Rates, Interest Rate Percentage.

No definition available.

Name:	mcb_LoansAndLeasesReceivableCommitmentsVariableRatesInterestRatePercentage
Namespace Prefix:	mcb_
Data Type:	dtr-types:percentItemType
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

Name:	us-gaap_FairValueOffBalanceSheetRisksDisclosureInformationLineItems
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Data Type:	xbrli:stringItemType
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Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.25)
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Name:	us-gaap_LitigationReserve
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Reflects the amount of cash required to fully fund agreements to provide advances to borrowers and lessees at stated interest rates.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 825
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI https://asc.fasb.org/extlink&oid=126941378&loc=d3e61044-112788

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 825
-Section 50
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=126941378&loc=d3e61082-112788