Real Estate - Schedule of Real Estate (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Acquisition and Disposition of Properties and Discontinued Operations [Abstract]
Land	$ 667,759	$ 658,835
Buildings and improvements	2,446,826	2,406,488
Tenant improvements	136,839	131,850
Construction in progress	27,439	18,642
Properties under capital lease	76,965	76,965
Total	3,355,828	3,292,780
Less: Accumulated depreciation	(378,272)	(339,862)
Operating real estate, net	2,977,556	2,952,918
Real estate under development, at cost	192,215	173,702
Net investments in real estate	$ 3,169,771	$ 3,126,620

Acquisition and Disposition of Properties and Discontinued Operations [Abstract]

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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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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 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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