Reporting Segments and Related Information - Revenue Components of Real Estate Segments (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Revenue from External Customer [Line Items]
Equity in earnings of unconsolidated joint ventures, net	$ 1,355	$ 876
Total expenses	12,076	11,694
Operating results from commercial/industrial and unconsolidated joint ventures	(172)	219
Real estate - commercial/industrial
Revenue from External Customer [Line Items]
Commercial/industrial revenues	2,320	2,826
Equity in earnings of unconsolidated joint ventures, net	1,355	876
Commercial/industrial revenues and equity in earnings of unconsolidated joint ventures	3,675	3,702
Total expenses	1,931	1,792
Operating results from commercial/industrial and unconsolidated joint ventures	$ 1,744	$ 1,910

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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