Amount of beneficial interest asset held by the entity in investee.

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Represents a distribution from non-consolidated REITS which constitutes a return of investment.

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Amount of distribution receivable by entity from liquidation proceeds from equity method investee company

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Represents the percentage of the equity method investee's outstanding preferred stock purchased by the entity during the reporting period.

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No definition available.

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The number of preferred stock purchased in the investee accounted for under the equity method of accounting.

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The cash inflow from liquidating trust.

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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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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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Amount of distribution received from equity method investee for return of investment, classified as investing activities. Excludes distribution for return on investment, classified as operating activities.

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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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Related Party Transactions and Investments in Non-Consolidated Entities - Equity in losses of investment in non-consolidated REITs (Details) - USD ($) $ in Thousands									1 Months Ended			12 Months Ended
	Apr. 03, 2019	Feb. 02, 2019	Sep. 27, 2018	Sep. 24, 2018	Aug. 17, 2018	Jul. 19, 2018	May 29, 2009	Dec. 27, 2007	Jun. 30, 2018	May 31, 2009	Dec. 31, 2007	Dec. 31, 2019	Dec. 31, 2018
Sponsored REITs
Equity in income (loss)													$ 6,793
Impairment charge									$ (300)				(309)
Proceeds received from liquidating trust												$ 1,470
Amount received													74,931
Distributions received from non-consolidated REITs
Distributions from non-consolidated REITs													710
East Wacker
Sponsored REITs
Equity in income (loss)													7,209
Preferred shares purchased								965.75			965.75
Percentage of outstanding preferred shares purchased								43.70%			43.70%
Liquidating distribution receivable				$ 70,000
Gain (loss) on liquidation				$ 7,100
Proceeds received from liquidating trust	$ 1,000
Amount received			$ 69,000
Distributions received from non-consolidated REITs
Distributions from non-consolidated REITs													657
Grand Boulevard
Sponsored REITs
Equity in income (loss)													(107)
Preferred shares purchased							175.5			175.5
Percentage of outstanding preferred shares purchased							27.00%			27.00%
Liquidating distribution receivable						$ 6,200
Gain (loss) on liquidation						$ (100)
Proceeds received from liquidating trust		$ 200
Amount received					$ 5,900
Beneficial interest												$ 100
Distributions received from non-consolidated REITs
Distributions from non-consolidated REITs													$ 53