Real Estate, Operating Real Estate, Real Estate Under Construction, and Equity Investment in Real Estate - Property Plant and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Investments in real estate:
Net investments in real estate	$ 1,935,212	$ 1,936,236
Real Estate
Investments in real estate:
Land	194,592	195,275
Buildings and improvements	1,005,915	1,015,501
Less: Accumulated depreciation	(118,667)	(112,061)
Net investments in real estate	1,081,840	1,098,715
Operating Real Estate
Investments in real estate:
Land	78,168	77,984
Buildings and improvements	428,903	425,165
Less: Accumulated depreciation	(45,800)	(41,969)
Net investments in real estate	$ 461,271	$ 461,180

Aggregate of the carrying amounts as of the balance sheet date of investments in building and building improvements.

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Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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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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