XML 139 R101.htm IDEA: XBRL DOCUMENT v2.4.1.9
Fair Value Measurements Quantitative information about Level III fair value measurements (Details) (USD $)
In Thousands, unless otherwise specified
 12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Repossessed Assets Fair Value Disclosure 1,132mbrg_RepossessedAssetsFairValueDisclosure  
Impaired Loans [Member] | Discounted appraised value [Member] | Level III [Member]    
Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Impaired Loans, Fair Value 4,510mbrg_ImpairedLoansReceivableFairValueDisclosure
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_LoansReceivableMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_ValuationTechniqueAxis
= mbrg_DiscountedAppraisedValueMember		  
Impaired Loans [Member] | Discounted appraised value [Member] | Minimum [Member] | Level III [Member]    
Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Discount rate 0.00%us-gaap_FairValueInputsDiscountRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_LoansReceivableMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
/ us-gaap_ValuationTechniqueAxis
= mbrg_DiscountedAppraisedValueMember		 0.00%us-gaap_FairValueInputsDiscountRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_LoansReceivableMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
/ us-gaap_ValuationTechniqueAxis
= mbrg_DiscountedAppraisedValueMember
Impaired Loans [Member] | Discounted appraised value [Member] | Maximum [Member] | Level III [Member]    
Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Discount rate 100.00%us-gaap_FairValueInputsDiscountRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_LoansReceivableMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
/ us-gaap_ValuationTechniqueAxis
= mbrg_DiscountedAppraisedValueMember		 100.00%us-gaap_FairValueInputsDiscountRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_LoansReceivableMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
/ us-gaap_ValuationTechniqueAxis
= mbrg_DiscountedAppraisedValueMember
Impaired Loans [Member] | Discounted appraised value [Member] | Weighted Average [Member] | Level III [Member]    
Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Discount rate 7.00%us-gaap_FairValueInputsDiscountRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_LoansReceivableMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= mbrg_DiscountedAppraisedValueMember		 4.00%us-gaap_FairValueInputsDiscountRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_LoansReceivableMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= mbrg_DiscountedAppraisedValueMember
Repossessed Assets [Member] | Market Approach Valuation Technique [Member] | Weighted Average [Member] | Level III [Member]    
Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Discount rate 50.00%us-gaap_FairValueInputsDiscountRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= mbrg_RepossessedAssetsMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= us-gaap_MarketApproachValuationTechniqueMember		  
Nonrecurring [Member]    
Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Impaired Loans, Fair Value 5,799mbrg_ImpairedLoansReceivableFairValueDisclosure
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember		 7,614mbrg_ImpairedLoansReceivableFairValueDisclosure
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
Nonrecurring [Member] | Level III [Member]    
Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Impaired Loans, Fair Value   1,858mbrg_ImpairedLoansReceivableFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
Repossessed Assets Fair Value Disclosure 1,132mbrg_RepossessedAssetsFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember