Summary of Investments in Real Estate (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Real Estate Properties [Line Items]
Investments in real estate, Book Value	$ 190,849	$ 274,672
Less: Accumulated depreciation and amortization	(13,671)	(28,768)
Investments in real estate, net	177,178	245,904
Multifamily real estate properties
Real Estate Properties [Line Items]
Investments in real estate, Book Value	17,230	17,163
Office real estate properties
Real Estate Properties [Line Items]
Investments in real estate, Book Value	77,056	130,125
Retail real estate properties
Real Estate Properties [Line Items]
Investments in real estate, Book Value	75,996	106,817
Parcels of land
Real Estate Properties [Line Items]
Investments in real estate, Book Value	$ 20,567	$ 20,567

Amount of accumulated depreciation pertaining to real estate investments for entities with a substantial portion of business acquiring and holding investment real estate.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 970
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-28(Column F))
-URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024

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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://fasb.org/us-gaap/role/ref/legacyRef
-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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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.

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