Real Estate Properties (Details) - USD ($) $ in Thousands	9 Months Ended
Jun. 30, 2017	Jun. 30, 2017	Sep. 30, 2016
Real Estate Properties
Land		$ 141,215	$ 128,409
Building		799,849	684,133
Building improvements		31,254	25,717
Real estate properties		972,318	838,259
Accumulated depreciation		(60,703)	(44,687)
Total real estate properties, net	$ 793,572	911,615	793,572
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real estate properties, beginning balance	793,572
Additions	224,449
Capitalized Costs and Improvements	7,261
Depreciation	(21,630)
Sales	(92,037)
Real estate properties, ending balance	911,615
Multi-family
Real Estate Properties
Total real estate properties, net	783,085	901,085	783,085
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real estate properties, beginning balance	783,085
Additions	224,449
Capitalized Costs and Improvements	7,136
Depreciation	(21,548)
Sales	(92,037)
Real estate properties, ending balance	901,085
Land
Real Estate Properties
Total real estate properties, net	8,021	8,021	8,021
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
Sales	0
Real estate properties, ending balance	8,021
Shopping centers/Retail \| Variable Interest Entity, Primary Beneficiary \| RBHTRB Newark Holdings LLC
Real Estate Properties
Total real estate properties, net	2,466	$ 2,509	$ 2,466
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real estate properties, beginning balance	2,466
Additions
Capitalized Costs and Improvements	125
Depreciation	(82)
Sales	0
Real estate properties, ending balance	$ 2,509

Investment Building

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- Definition

Investment Building Improvements

+ References

No definition available.

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- Definition

Represents the depreciation and amortization in real estate investment property.

+ References

No definition available.

+ Details

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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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- 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

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- Definition

Reflects for the period the total of the carrying amount of the commercial, industrial and residential land and buildings sold plus certain overhead and other costs incurred to place the real estate in saleable condition, capitalized interest costs in the properties sold, and inventory impairment losses recognized. This element would most likely be used by an entity whose principal activities involve real estate or which has significant real estate operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 4
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6812-107765

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.13)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The cumulative amount of depreciation for real estate property held for investment purposes.

+ 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(3))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

Amount of real estate investment property 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

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- 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://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

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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

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.

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