PROPERTIES (Summary of our investment in leased real estate properties) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Total real estate investments	$ 8,985,994	$ 7,746,410
Less accumulated depreciation	(1,787,425)	(1,562,619)
Real estate investments - net	7,198,569	6,183,791
Building
Property, Plant and Equipment [Line Items]
Total real estate investments	7,056,106	6,056,820
Land
Property, Plant and Equipment [Line Items]
Total real estate investments	901,246	786,174
Furniture and Equipment
Property, Plant and Equipment [Line Items]
Total real estate investments	515,421	447,610
Building And Site Improvements
Property, Plant and Equipment [Line Items]
Total real estate investments	287,655	250,917
Construction in Progress
Property, Plant and Equipment [Line Items]
Total real estate investments	$ 225,566	$ 204,889

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No definition available.

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(3))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.7-03.1(d))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

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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.

+ References

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