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- Definition

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

Loans Payable, Term Modification

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Variable Interest Entity, Number of Entities

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Area of a real estate property.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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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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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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Amount of gain (loss) on sale or disposal of an equity method investment.

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- Definition

Gross amount of debt extinguished.

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No definition available.

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- Definition

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

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Including the current and noncurrent portions, aggregate carrying value as of the balance sheet date of loans payable (with maturities initially due after one year or beyond the operating cycle if longer).

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The cash inflow associated with the deconsolidation of a previously consolidated subsidiary or sale of an entity that is related to it but not strictly controlled.

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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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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) ft² in Thousands				3 Months Ended		9 Months Ended		12 Months Ended
	Jun. 30, 2019 USD ($)	Jun. 24, 2019 USD ($)	Apr. 17, 2013 USD ($)	Sep. 30, 2019 USD ($) ft² VIE	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) ft² VIE	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017	Jan. 01, 2018 USD ($)	Dec. 31, 2013 property
Variable Interest Entity [Line Items]
Number of variable interest entities \| VIE				0		0
Proceeds from sale and transfer of investment properties, net						$ 183,588,000	$ 254,424,000
Provision for asset impairment				$ 0	$ 1,405,000	1,443,000	3,673,000
Proceeds from liquidation of unconsolidated entity						30,000,000	0
Retail \| Rockwell Plaza
Variable Interest Entity [Line Items]
Provision for asset impairment						794,000
Loss on sale						307,000
Retail \| Bryant Square
Variable Interest Entity [Line Items]
Provision for asset impairment					773,000		2,020,000
Loss on sale							2,148,000
IAGM Retail Fund I, LLC \| Retail
Variable Interest Entity [Line Items]
Provision for asset impairment					$ 1,405,000		3,673,000
IAGM Retail Fund I, LLC \| Retail \| Rockwell Plaza
Variable Interest Entity [Line Items]
Proceeds from sale and transfer of investment properties, net						$ 20,500,000
Area of real estate \| ft²				255		255
Provision for asset impairment						$ 1,443,000
Loss on sale						559,000
IAGM Retail Fund I, LLC \| Retail \| Bryant Square
Variable Interest Entity [Line Items]
Loss on sale							$ 3,905,000
Unconsolidated Entities \| IAGM Retail Fund I, LLC
Variable Interest Entity [Line Items]
Number of retail properties contributed \| property											14
Proceeds from sale and transfer of investment properties, net			$ 15,625,000
Equity investment basis adjustment, amortization period									30 years
Deferred gain on sale of property										$ 12,756,000
Unconsolidated Entities \| Downtown Railyard Venture, LLC
Variable Interest Entity [Line Items]
Proceeds from liquidation of unconsolidated entity		$ 30,000,000
Other-than-temporary-impairment on unconsolidated entity								$ 29,933,000
Gain (loss) on transaction								$ 0
Mortgages
Variable Interest Entity [Line Items]
Extinguishment mortgage payable						$ 16,250,000
Extended Maturity \| IAGM Retail Fund I, LLC
Variable Interest Entity [Line Items]
Extension period	1 year
Non Recourse, Mortgage Loan \| IAGM Retail Fund I, LLC
Variable Interest Entity [Line Items]
Carrying value of loans payable	$ 14,872,000
Loans Payable \| Non Recourse, Mortgage Loan \| IAGM Retail Fund I, LLC
Variable Interest Entity [Line Items]
Debt instrument, face amount	$ 15,103,000