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Amount before amortization of leases acquired as part of a real property acquisition at below market lease rate with a finite life.

No definition available.

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Amount after amortization of leases acquired as part of a real property acquisition at below market lease rate with a finite life.

No definition available.

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Data Type:	xbrli:monetaryItemType
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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_PropertyPlantAndEquipmentLineItems
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Data Type:	xbrli:stringItemType
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Amount of accumulated depreciation pertaining to real estate investments for entities with a substantial portion of business acquiring and holding investment real estate.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 970
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-28(Column F))
-URI https://asc.fasb.org/extlink&oid=120402810&loc=d3e638233-123024

Name:	us-gaap_RealEstateAccumulatedDepreciation
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Data Type:	xbrli:monetaryItemType
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Amount, before accumulated depreciation, of real estate investment by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate. Excludes real estate not held as investment or interest.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 970
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-28(Column E))
-URI https://asc.fasb.org/extlink&oid=120402810&loc=d3e638233-123024

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Amount after accumulated depreciation of real estate held for investment for entities with a substantial portion of business acquiring and holding investment real estate.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 970
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-28)
-URI https://asc.fasb.org/extlink&oid=120402810&loc=d3e638233-123024

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Name:	srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=nxdt_NexpointDominionLandLlcMember
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Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=us-gaap_LandMember
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Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=us-gaap_BuildingAndBuildingImprovementsMember
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Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=nxdt_IntangibleLeaseLiabilitiesMember
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