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Name of property acquired.

No definition available.

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- References

No definition available.

Name:	mrc_ConsolidatedOperatingPropertiesAbstract
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Location name of property.

No definition available.

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Name of property.

No definition available.

Name:	mrc_ConsolidatingOperatingPropertiesNameOfProperty
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Owner of the property.

No definition available.

Name:	mrc_ConsolidatingOperatingPropertiesPropertyOwner
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Amount of net lease hold assets (liability).

No definition available.

Name:	mrc_LeaseholdAssetLiabilityNet
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Number of tenants in the property.

No definition available.

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The percentage of the total operating properties owned by the Operating Partnership.

No definition available.

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The year of property built.

No definition available.

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- References

No definition available.

Name:	us-gaap_AssetAcquisitionAbstract
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Amount of consideration transferred in asset acquisition. Includes, but is not limited to, cash, liability incurred by acquirer, and equity interest issued by acquirer.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- References

No definition available.

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Date when acquirer obtains control of acquired asset, in YYYY-MM-DD format.

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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Name:	us-gaap_Depreciation
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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Namespace Prefix:
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Balance Type:
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Name:	us-gaap_AssetAcquisitionAxis=mrc_PonDoLeoApartmentBuildingMember
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Data Type:	na
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Name:	us-gaap_AssetAcquisitionAxis=mrc_HollywoodPropertyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_AssetAcquisitionAxis=mrc_ShorelineApartmentsBuildingMember
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Data Type:	na
Balance Type:
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Name:	us-gaap_AssetAcquisitionAxis=mrc_SatellitePlaceBuildingMember
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Data Type:	na
Balance Type:
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Name:	us-gaap_AssetAcquisitionAxis=mrc_FirstMainOfficeBuildingMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_AssetAcquisitionAxis=mrc_MainOfficeBuildingMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Data Type:	na
Balance Type:
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Name:	us-gaap_AssetAcquisitionAxis=mrc_MainStreetWestOfficeBuildingMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_AssetAcquisitionAxis=mrc_CampusLaneOfficeBuildingMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Data Type:	na
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Data Type:	na
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Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_LandMember
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Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_BuildingMember
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Data Type:	na
Balance Type:
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Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_BuildingImprovementsMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=mrc_TenantImprovementsMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=mrc_LeaseInPlaceMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=mrc_LeasingCommissionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=mrc_LegalMarketingLeaseMember
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