Real Estate - Summary of Carrying Amounts of Investment in Real Estate (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Land	$ 5,779,686	$ 5,785,367
Depreciable property:
Buildings and improvements	19,211,662	18,464,484
Furniture, fixtures and equipment	2,125,441	1,970,033
In-Place lease intangibles	503,241	486,137
Projects under development:
Projects under development	163,659	411,134
Land held for development:
Land held for development	82,026	86,170
Investment in real estate	27,865,715	27,203,325
Accumulated depreciation	(8,260,846)	(7,859,657)
Investment in real estate, net	19,604,869	19,343,668
Land [Member]
Projects under development:
Projects under development	4,121	23,531
Land held for development:
Land held for development	46,160	46,160
Construction-in-progress [Member]
Projects under development:
Projects under development	159,538	387,603
Land held for development:
Land held for development	$ 35,866	$ 40,010

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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