Name:	mrbk_LoanAndLeaseReceivableAllowanceCumulativeDaysPastDueChargeOffs
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The amount of look-back period utilized to calculate loss rates.

No definition available.

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The number of mortgage loan production offices.

No definition available.

Name:	mrbk_NumberOfMortgageLoanProductionOffices
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The general amount of time between the issuance of a loan commitment and closing and sale of the loan.

No definition available.

Name:	mrbk_TimeElapsingBetweenLoanCommitmentAndSaleOfLoan
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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

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No definition available.

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No definition available.

Name:	us-gaap_MortgageBankingAbstract
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Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(4))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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No definition available.

Name:	us-gaap_OtherRealEstateAbstract
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No definition available.

Name:	us-gaap_ProvisionForLoanAndLeaseLossesAbstract
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Data Type:	xbrli:stringItemType
Balance Type:	na
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Namespace Prefix:
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Balance Type:
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Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
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Name:	srt_StatementGeographicalAxis=mrbk_PennsylvaniaDelawareAndNewJerseyMember
Namespace Prefix:
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