Real Estate - Summary of Carrying Amounts of Investment in Real Estate (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Land	$ 5,794,771	$ 5,936,188
Depreciable property:
Buildings and improvements	18,626,029	18,904,686
Furniture, fixtures and equipment	1,962,223	1,916,458
In-Place lease intangibles	487,970	497,957
Projects under development:
Projects under development	337,696	181,630
Land held for development:
Land held for development	103,900	96,688
Investment in real estate	27,312,589	27,533,607
Accumulated depreciation	(7,738,318)	(7,276,786)
Investment in real estate, net	19,574,271	20,256,821
Land [Member]
Projects under development:
Projects under development	23,531	23,531
Land held for development:
Land held for development	64,490	64,460
Construction-in-progress [Member]
Projects under development:
Projects under development	314,165	158,099
Land held for development:
Land held for development	$ 39,410	$ 32,228

Land held for development.

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- Definition

Projects under development.

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No definition available.

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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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- 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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