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- Definition

Equity Investment Basis Adjustment, Amortization Period

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Equity Method Investment, Summarized Financial Information, Impairments

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Investments in Affiliates, Subsidiaries, Associates, and Joint Ventures, Properties Contributed

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- Definition

Number of Retail Properties Impaired

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- Definition

The charge against earnings resulting from the aggregate write down of assets from their carrying value to their fair value. Includes charges from both continued and discontinued operations.

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- Definition

Area of a real estate property.

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- Definition

Amount of facility held for productive use including, but not limited to, office, production, storage and distribution facilities, acquired at the acquisition date.

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Amount of real estate acquired, at the acquisition date.

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- Definition

The amount of property, plant, and equipment recognized as of the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=84160947&loc=d3e2207-128464

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- Definition

Amount of gain on the sale of property that does not qualify for gain recognition as of the balance sheet date.

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No definition available.

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- Definition

Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The cash outflow associated with extending a long-term loan to a related party. Alternate caption: Payments for Advances to Affiliates.

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No definition available.

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- Definition

Cash received from the sale of real estate that is held for investment, that is, it is part of an investing activity during the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585

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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.

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No definition available.

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Investment in Consolidated and Unconsolidated Entities - Narrative (Details) $ in Thousands		3 Months Ended			6 Months Ended		12 Months Ended
	Apr. 17, 2013 USD ($)	Jun. 30, 2018 USD ($) ft²	Mar. 31, 2018 USD ($)	Jun. 30, 2017 USD ($) ft²	Jun. 30, 2018 USD ($) ft² Property	Jun. 30, 2017 USD ($) ft²	Dec. 31, 2017 USD ($)	Dec. 31, 2013 Properties
Variable Interest Entity [Line Items]
Fair value of parking garage		$ 143,444		$ 256,583	$ 143,444	$ 256,583
Land		21,629		75,194	21,629	75,194
Building and other improvements		121,815		181,389	121,815	181,389
Proceeds from sale and transfer of investment properties, net					186,778	96,468
Provision for asset impairment		1,596		$ 0	$ 2,268
Number of properties impaired \| Property					2
Carrying value of investment		188,447			$ 188,447		$ 180,764
Gross disposition price					212,950	99,330
Provision for asset impairment					797	$ 16,440
IAGM Retail Fund I, LLC
Variable Interest Entity [Line Items]
Carrying value of investment		129,519			129,519		123,693
The Plaza Midtown, Atlanta, GA
Variable Interest Entity [Line Items]
Land		1,963			1,963		1,963
Building and other improvements		$ 8,827			$ 8,827		$ 8,827
Retail
Variable Interest Entity [Line Items]
Square Feet \| ft²		1,759,000		761,000	1,759,000	761,000
Gross disposition price					$ 212,950	$ 99,330
Bryant Square
Variable Interest Entity [Line Items]
Proceeds from sale and transfer of investment properties, net			$ 2,148
Provision for asset impairment		$ 878			1,248
Bryant Square \| Retail
Variable Interest Entity [Line Items]
Proceeds from sale and transfer of investment properties, net					$ 3,905
Square Feet \| ft²		268,000			268,000
Gross disposition price					$ 38,000
Provision for asset impairment					$ 672
Unconsolidated Entities \| IAGM Retail Fund I, LLC
Variable Interest Entity [Line Items]
Number of retail properties contributed \| Properties								14
Proceeds from sale and transfer of investment properties, net	$ 15,625
Equity investment basis adjustment, amortization period							30 years
Deferred gain on sale of property							$ 12,756
PGA Plaza and Kennesaw Marketplace [Member]
Variable Interest Entity [Line Items]
Loan advanced to VIE		$ 152,300