Real Estate Properties - Summary of Real Estate Properties Owned (Details) $ in Thousands	9 Months Ended
Jun. 30, 2018 USD ($)
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real estate properties, beginning balance	$ 911,250
Additions	264,089
Capitalized Costs and Improvements	11,629
Depreciation	(28,088)
Sales	(104,396)
Real estate properties, ending balance	1,054,484
Multi-family
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real estate properties, beginning balance	890,300
Additions	240,374
Capitalized Costs and Improvements	11,629
Depreciation	(28,006)
Sales	(104,396)
Real estate properties, ending balance	1,009,901
Multi-family \| West Nashville, TN
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real estate properties, beginning balance	10,448
Additions	23,715
Capitalized Costs and Improvements	0
Depreciation	0
Sales	0
Real estate properties, ending balance	34,163
Land \| 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
Sales	0
Real estate properties, ending balance	8,021
Shopping centers/Retail \| RBHTRB Newark Holdings LLC \| Yonkers, NY \| VIE
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Real estate properties, beginning balance	2,481
Additions	0
Capitalized Costs and Improvements	0
Depreciation	(82)
Sales	0
Real estate properties, ending balance	$ 2,399

Represents the depreciation and amortization in real estate investment property.

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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.

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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)
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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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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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