Real Estate - Summary of Carrying Amounts of Investment in Real Estate (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Land	$ 5,918,994	$ 5,875,803
Depreciable property:
Buildings and improvements	18,440,716	18,232,625
Furniture, fixtures and equipment	1,761,906	1,722,231
In-Place lease intangibles	488,682	481,045
Projects under development:
Construction-in-progress	135,191	109,409
Land held for development:
Land	91,647	89,909
Construction-in-progress	135,191	109,409
Investment in real estate	26,837,136	26,511,022
Accumulated depreciation	(6,900,496)	(6,696,281)
Investment in real estate, net	19,936,640	19,814,741
Projects under development [Member]
Projects under development:
Land	25,430	25,429
Construction-in-progress	109,761	83,980
Land held for development:
Construction-in-progress	109,761	83,980
Land held for development [Member]
Projects under development:
Construction-in-progress	30,609	28,871
Land held for development:
Land	61,038	61,038
Construction-in-progress	$ 30,609	$ 28,871

Carrying amount of land for a real estate project that has not yet been completed.

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- Definition

Land held for development.

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No definition available.

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Projects under development.

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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
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- Definition

This element represents the amount of value allocated by a lessor (acquirer) to lease agreements which exist at acquisition of a leased property. Such amount may include the value assigned to existing tenant relationships and excludes the market adjustment component of the value assigned for above or below-market leases acquired.

+ References

No definition available.

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- Definition

Amount before accumulated depreciation of fixtures and equipment. Includes, but is not limited to, machinery, equipment, and engines.

+ References

No definition available.

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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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- Definition

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

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- Definition

Carrying amount of land available for development.

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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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