Real Estate - Schedule of Real Estate (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Acquisition and Disposition of Properties and Discontinued Operations [Abstract]
Land	$ 667,847	$ 658,835
Buildings and improvements	2,444,871	2,406,488
Tenant improvements	136,682	131,850
Construction in progress	21,060	18,642
Properties under capital lease	76,965	76,965
Total	3,347,425	3,292,780
Less: Accumulated depreciation	(359,048)	(339,862)
Operating real estate, net	2,988,377	2,952,918
Real estate under development, at cost	182,380	173,702
Net investments in real estate	$ 3,170,757	$ 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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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- Definition

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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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
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-Paragraph 1
-Subparagraph (SX 210.7-03.10)
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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The cumulative amount of depreciation for real estate property held for investment purposes.

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- Definition

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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-Publisher FASB
-Name Accounting Standards Codification
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