SELF STORAGE PROPERTIES (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Real Estate [Abstract]
Land	$ 690,581		$ 690,581		$ 649,938
Buildings and improvements	2,683,288		2,683,288		2,435,171
Furniture and equipment	7,549		7,549		6,610
Total self storage properties	3,381,418		3,381,418		3,091,719
Less accumulated depreciation	(416,423)		(416,423)		(337,822)
Self storage properties, net	2,964,995		2,964,995		$ 2,753,897
Depreciation expense related to self storage properties	$ 26,600	$ 23,800	$ 78,600	$ 68,000

The expense recognized in the current period that allocates the cost of nonproduction tangible assets over their useful lives.

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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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Aggregate of the carrying amounts as of the balance sheet date of investments in building and building improvements.

+ References

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

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

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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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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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