Real Estate Properties (Details) - USD ($)	3 Months Ended
Dec. 31, 2016	Dec. 31, 2016	Sep. 30, 2016
Real Estate Properties
Land		$ 126,242,000	$ 128,409,000
Building		638,348,000	684,133,000
Building improvements		26,964,000	25,717,000
Real estate properties		791,554,000	838,259,000
Accumulated depreciation		(45,371,000)	(44,687,000)
Real estate loan		5,900,000	19,500,000
Total real estate properties, net	$ 793,572,000	746,183,000	793,572,000
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real estate properties, beginning balance	793,572,000
Additions	47,974,000
Capitalized Costs and Improvements	2,971,000
Depreciation	(6,297,000)
Sales	(92,037,000)
Real estate properties, ending balance	746,183,000
Multi-family
Real Estate Properties
Total real estate properties, net	783,085,000	735,597,000	783,085,000
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real estate properties, beginning balance	783,085,000
Additions	47,974,000
Capitalized Costs and Improvements	2,845,000
Depreciation	(6,270,000)
Sales	(92,037,000)
Real estate properties, ending balance	735,597,000
Land
Real Estate Properties
Total real estate properties, net	8,021,000	8,021,000	8,021,000
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real estate properties, beginning balance	8,021,000
Additions	0
Capitalized Costs and Improvements	0
Depreciation	0
Sales	0
Real estate properties, ending balance	8,021,000
Shopping centers/Retail \| Variable Interest Entity, Primary Beneficiary \| RBHTRB Newark Holdings LLC
Real Estate Properties
Total real estate properties, net	2,466,000	2,565,000	2,466,000
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real estate properties, beginning balance	2,466,000
Additions	0
Capitalized Costs and Improvements	126,000
Depreciation	(27,000)
Sales	0
Real estate properties, ending balance	$ 2,565,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| RBHTRB Newark Holdings LLC
Real Estate Properties
Real estate loan		$ 5,900,000	$ 19,500,000

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=28358313&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 balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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

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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.

+ Details

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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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