Real Estate - Schedule of Real Estate (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Acquisition And Disposition Of Properties And Discontinued Operations [Abstract]
Land	$ 705,402	$ 710,469
Buildings and improvements	2,574,459	2,594,828
Tenant improvements	157,502	151,154
Construction in progress	30,413	44,092
Properties under capital lease		76,965
Finance lease, right-of-use asset	82,629
Operating lease, right-of-use asset	11,871
Total	3,562,276	3,577,508
Less: Accumulated depreciation	(438,033)	(416,657)
Operating real estate, net	3,124,243	3,160,851
Real estate under development, at cost	193,315	120,297
Net investments in real estate	$ 3,317,558	$ 3,281,148

Acquisition and disposition of properties and discontinued operations.

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- Definition

Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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The current amount of expenditures for a real estate project that has not yet been completed.

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Amount of lessee's right to use underlying asset under finance lease.

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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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Amount of lessee's right to use underlying asset under operating lease.

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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 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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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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Amount of real estate investments, 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; (7) other real estate investments; (8) real estate joint ventures; and (9) unconsolidated real estate and other joint ventures not separately presented.

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Carrying amount as of the balance sheet date of improvements having a life longer than one year that were made for the benefit of one or more tenants.

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