Real Estate Properties (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Dec. 31, 2014
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the beginning of the period	$ 635,612us-gaap_RealEstateInvestmentPropertyNet
Additions	27,950
Capitalized Costs and Improvements	17,227
Depreciation, amortization and other changes	(10,902)
Balance at the end of the period	669,887us-gaap_RealEstateInvestmentPropertyNet
Apartment Building [Member]
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the beginning of the period	511,866
Additions	27,950
Capitalized Costs and Improvements	9,007
Depreciation, amortization and other changes	(10,374)
Balance at the end of the period	538,449
Commercial Mixed Use Property [Member] \| Variable Interest Entity Primary Beneficiary [Member] \| RBHTRB Newark Holdings LLC [Member]
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the beginning of the period	113,021
Additions	0
Capitalized Costs and Improvements	8,216
Depreciation, amortization and other changes	(500)
Balance at the end of the period	120,737
Land [Member]
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the beginning of the period	7,972
Additions	0
Capitalized Costs and Improvements	0
Depreciation, amortization and other changes	0
Balance at the end of the period	7,972
Retail Site [Member] \| Variable Interest Entity Primary Beneficiary [Member] \| RBHTRB Newark Holdings LLC [Member]
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the beginning of the period	2,678
Additions	0
Capitalized Costs and Improvements	4
Depreciation, amortization and other changes	(27)
Balance at the end of the period	2,655
Co Op Condominium Apartment Building [Member]
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at the beginning of the period	75
Additions	0
Capitalized Costs and Improvements	0
Depreciation, amortization and other changes	(1)
Balance at the end of the period	$ 74

Represents the depreciation, amortization and other reductions in real estate investment property.

No definition available.

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Data Type:	xbrli:monetaryItemType
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- Definition

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

+ References

No definition available.

+ Details

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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

Amount of real estate investment property, 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; and (7) other real estate investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-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=6879938&loc=d3e572229-122910

+ Details

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- Details

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- Details

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- Details

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- Details

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Data Type:	na
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- Details

Name:	us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=us-gaap_LandMember
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- Details

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