ACQUISITIONS AND DISPOSITIONS - Narrative (Details) $ in Millions	3 Months Ended
Mar. 31, 2024 USD ($) property
Asset Acquisition [Line Items]
Net gain on disposition	$ 61.2
Third Party
Asset Acquisition [Line Items]
Self storage property disposed \| property	39
Net proceeds from sale	$ 265.1
Joint Venture
Asset Acquisition [Line Items]
Self storage property disposed \| property	56
Net proceeds from sale	$ 343.7

Number Of Self Storage Properties, Disposition

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 805
-SubTopic 50
-Name Accounting Standards Codification
-Section 15
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480123/805-50-15-3

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- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-28

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- Definition

The cash inflow from the sale of formerly productive land held for sale, anything permanently fixed to it, including buildings, structures on it, and so forth.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 12
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-12

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