Real Estate Held for Sale in Consolidated VIEs (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Investment [Line Items]
Real estate held for sale before accumulated depreciation and amortization	$ 64,202	$ 0
Riverchase Landing \| VIE, Primary Beneficiary
Investment [Line Items]
Land	7,000
Building and improvements	53,468
Furniture, fixtures and equipment	2,150
Lease intangible	5,340
Real estate held for sale before accumulated depreciation and amortization	67,958
Accumulated depreciation	(647)
Accumulated amortization of lease intangible	(3,109)
Real estate held for sale in consolidated variable interest entities	64,202
Depreciation	600
Amortization	$ 3,100

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
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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
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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 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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