Real Estate Held for Sale in Consolidated VIEs (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
Mar. 31, 2018	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Investment [Line Items]
Real estate held for sale before accumulated depreciation and amortization	$ 29,293	$ 29,293		$ 64,202
Riverchase Landing \| VIE, Primary Beneficiary
Investment [Line Items]
Gain on sale	2,300
Land	2,650	2,650		7,000
Building and improvements	25,757	25,757		53,468
Furniture, fixtures and equipment	838	838		2,150
Lease intangible	2,802	2,802		5,340
Real estate held for sale before accumulated depreciation and amortization	32,047	32,047		67,958
Accumulated depreciation	(418)	(418)		(647)
Accumulated amortization of lease intangible	(2,336)	(2,336)		(3,109)
Real estate held for sale in consolidated variable interest entities	$ 29,293	29,293		$ 64,202
Depreciation		0	$ 0
Amortization		$ 0	$ 0

Line items represent reporting 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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 12
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The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before accumulated depreciation of fixtures and equipment. Includes, but is not limited to, machinery, equipment, and engines.

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The net gain (loss) resulting from sales and other disposals of real estate owned for investment purposes.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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Carrying amount as of the balance sheet date of investments in land and buildings held for sale, excluding real estate considered to be inventory of the entity.

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

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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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