Acquisitions and Dispositions - Property Acquisitions (Details)	9 Months Ended
Sep. 30, 2019 USD ($) property property_Unit	Sep. 30, 2018 USD ($) property
Real Estate Properties [Line Items]
No. of Units \| property_Unit	10,152
Acquisition Mortgage Debt	$ 80,097,000
Initial BRT Equity	$ 11,231,000	$ 12,370,000
Corporate Joint Venture \| VIE \| Apartment Building \| Property Acquisition
Real Estate Properties [Line Items]
No. of Units \| property	840	1,597
Purchase Price	$ 109,465,000	$ 199,876,000
Initial BRT Equity	27,176,000	41,749,000
Capitalized Acquisition Costs	$ 1,245,000	$ 2,611,000
Corporate Joint Venture \| VIE \| Kannapolis, North Carolina \| Apartment Building \| Property Acquisition
Real Estate Properties [Line Items]
No. of Units \| property	312
Purchase Price	$ 48,065,000
Initial BRT Equity	$ 11,231,000
Ownership Percentage	65.00%
Capitalized Acquisition Costs	$ 559,000
Corporate Joint Venture \| VIE \| Birmingham, Alabama \| Apartment Building \| Property Acquisition
Real Estate Properties [Line Items]
No. of Units \| property	328
Purchase Price	$ 43,000,000
Initial BRT Equity	$ 11,625,000
Ownership Percentage	80.00%
Capitalized Acquisition Costs	$ 546,000
Corporate Joint Venture \| VIE \| Auburn, Alabama \| Apartment Building \| Property Acquisition
Real Estate Properties [Line Items]
No. of Units \| property	200
Purchase Price	$ 18,400,000
Initial BRT Equity	$ 4,320,000
Ownership Percentage	80.00%
Capitalized Acquisition Costs	$ 140,000
Corporate Joint Venture \| VIE \| Ocoee, FL \| Apartment Building \| Property Acquisition
Real Estate Properties [Line Items]
No. of Units \| property		522
Purchase Price		$ 71,347,000
Initial BRT Equity		$ 12,370,000
Ownership Percentage		50.00%
Capitalized Acquisition Costs		$ 1,047,000
Corporate Joint Venture \| VIE \| Lawrenceville, GA \| Apartment Building \| Property Acquisition
Real Estate Properties [Line Items]
No. of Units \| property		586
Purchase Price		$ 77,229,000
Initial BRT Equity		$ 15,179,000
Ownership Percentage		50.00%
Capitalized Acquisition Costs		$ 767,000
Corporate Joint Venture \| VIE \| Daytona, FL \| Apartment Building \| Property Acquisition
Real Estate Properties [Line Items]
No. of Units \| property		208
Purchase Price		$ 20,500,000
Initial BRT Equity		$ 6,900,000
Ownership Percentage		80.00%
Capitalized Acquisition Costs		$ 386,000
Corporate Joint Venture \| VIE \| Grand Prairie, TX \| Apartment Building \| Property Acquisition
Real Estate Properties [Line Items]
No. of Units \| property		281
Purchase Price		$ 30,800,000
Initial BRT Equity		$ 7,300,000
Ownership Percentage		50.00%
Capitalized Acquisition Costs		$ 411,000
Acquisition Mortgages Debt \| Corporate Joint Venture \| VIE \| Apartment Building \| Property Acquisition
Real Estate Properties [Line Items]
Acquisition Mortgage Debt	80,097,000	140,110,000
Acquisition Mortgages Debt \| Corporate Joint Venture \| VIE \| Kannapolis, North Carolina \| Apartment Building \| Property Acquisition
Real Estate Properties [Line Items]
Acquisition Mortgage Debt	33,347,000
Acquisition Mortgages Debt \| Corporate Joint Venture \| VIE \| Birmingham, Alabama \| Apartment Building \| Property Acquisition
Real Estate Properties [Line Items]
Acquisition Mortgage Debt	32,250,000
Acquisition Mortgages Debt \| Corporate Joint Venture \| VIE \| Auburn, Alabama \| Apartment Building \| Property Acquisition
Real Estate Properties [Line Items]
Acquisition Mortgage Debt	$ 14,500,000
Acquisition Mortgages Debt \| Corporate Joint Venture \| VIE \| Ocoee, FL \| Apartment Building \| Property Acquisition
Real Estate Properties [Line Items]
Acquisition Mortgage Debt		53,060,000
Acquisition Mortgages Debt \| Corporate Joint Venture \| VIE \| Lawrenceville, GA \| Apartment Building \| Property Acquisition
Real Estate Properties [Line Items]
Acquisition Mortgage Debt		54,447,000
Acquisition Mortgages Debt \| Corporate Joint Venture \| VIE \| Daytona, FL \| Apartment Building \| Property Acquisition
Real Estate Properties [Line Items]
Acquisition Mortgage Debt		13,608,000
Acquisition Mortgages Debt \| Corporate Joint Venture \| VIE \| Grand Prairie, TX \| Apartment Building \| Property Acquisition
Real Estate Properties [Line Items]
Acquisition Mortgage Debt		$ 18,995,000

Represents the contract purchase of the real estate investment property.

No definition available.

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- Definition

This element represents acquisition-related costs incurred in connection with real estate investments acquired other than through foreclosure which costs have been expensed during the period.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

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-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

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- Definition

The number of units in a real estate property owned as of the balance sheet date.

+ References

No definition available.

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- Definition

The cash outflow associated with the investment in or advances to an entity in which the reporting entity shares control of the entity with another party or group.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585

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- Definition

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.

+ References

No definition available.

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- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 5A
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