Land, Buildings and Improvements and Assets Held for Sale - Property Plant and Equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Real Estate Investment Property At Cost
Less: Accumulated depreciation	$ (2,257,551)	$ (2,035,995)
Investments in real estate	14,133,970	13,848,730
Operating Properties
Real Estate Investment Property At Cost
Land	10,452	10,452
Buildings and improvements	72,884	72,631
Less: Accumulated depreciation	(12,593)	(11,241)
Investments in real estate	70,743	71,842
Assets Leased to Others
Real Estate Investment Property At Cost
Land	1,896,845	1,875,065
Buildings and improvements	8,242,592	7,828,439
Real estate under construction	64,802	69,604
Less: Accumulated depreciation	(1,072,469)	(950,452)
Investments in real estate	$ 9,131,770	$ 8,822,656

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

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
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Aggregate of the carrying amounts as of the balance sheet date of investments in building and building improvements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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The cumulative amount of depreciation for real estate property held for investment purposes.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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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