Real Estate Properties - Summary of Real Estate Properties Owned (Details) $ in Thousands	9 Months Ended
Sep. 30, 2019 USD ($)
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real estate properties, beginning balance	$ 1,029,239
Additions	110,710
Capitalized Costs and Improvements	25,583
Depreciation	(29,914)
Real estate properties, ending balance	1,112,896
Real Estate
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Sales	(22,722)
Apartment Building
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real estate properties, beginning balance	964,320
Additions	110,710
Capitalized Costs and Improvements	10,004
Depreciation	(29,286)
Real estate properties, ending balance	1,033,026
Apartment Building \| Real Estate
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Sales	(22,722)
Apartment Building \| West Nashville, TN
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real estate properties, beginning balance	54,555
Additions	0
Capitalized Costs and Improvements	15,579
Depreciation	(541)
Real estate properties, ending balance	69,593
Apartment Building \| West Nashville, TN \| Real Estate
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Sales	0
Land - Daytona, FL \| Daytona, FL
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real estate properties, beginning balance	8,021
Additions	0
Capitalized Costs and Improvements	0
Depreciation	0
Real estate properties, ending balance	8,021
Land - Daytona, FL \| Daytona, FL \| Real Estate
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Sales	0
Shopping centers/Retail - Yonkers, NY \| RBHTRB Newark Holdings LLC \| Yonkers, NY \| VIE
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real estate properties, beginning balance	2,343
Additions	0
Capitalized Costs and Improvements	0
Depreciation	(87)
Real estate properties, ending balance	2,256
Shopping centers/Retail - Yonkers, NY \| RBHTRB Newark Holdings LLC \| Yonkers, NY \| VIE \| Real Estate
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Sales	$ 0

Represents the depreciation and amortization in real estate investment property.

No definition available.

Name:	brt_RealEstateDepreciationAndAmortization
Namespace Prefix:	brt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the aggregate of the amount of improvements and costs capitalized to real estate investments during the period.

+ References

No definition available.

+ Details

Name:	brt_RealEstateImprovementsAndOtherAdditions
Namespace Prefix:	brt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of increase in real estate investments from acquisitions other than through foreclosure for entities with a substantial portion of business acquiring and holding investment real estate. Excludes improvements and costs capitalized to real estate investments during the period.

+ References

No definition available.

+ Details

Name:	brt_RealEstateInvestmentPropertyOtherAcquisitions
Namespace Prefix:	brt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(a),(d))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

+ Details

Name:	us-gaap_CostOfGoodsAndServicesSold
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of real estate investments, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; (7) other real estate investments; (8) real estate joint ventures; and (9) unconsolidated real estate and other joint ventures not separately presented.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(d))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

+ Details

Name:	us-gaap_RealEstateInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

Name:	us-gaap_ReconciliationOfCarryingAmountOfRealEstateInvestmentsRollForward
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	srt_ProductOrServiceAxis=us-gaap_RealEstateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=srt_ApartmentBuildingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementGeographicalAxis=brt_WestNashvilleTNMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=us-gaap_LandMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementGeographicalAxis=brt_DaytonaFLMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=srt_RetailSiteMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=brt_RBHTRBNewarkHoldingsLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementGeographicalAxis=brt_YonkersNYMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis=us-gaap_VariableInterestEntityPrimaryBeneficiaryMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: