Investment in Storage Facilities and Intangible Assets - Summary of Activity in Storage Facilities (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2023 USD ($)
Cost:
Beginning balance	$ 8,171,806
Improvements and equipment additions	22,365
Net increase in construction in progress	3,232
Dispositions	(1,406)
Ending balance	8,195,997
Accumulated Depreciation:
Beginning balance	1,170,520
Additions during the period	45,722
Dispositions	(894)
Ending balance	$ 1,215,348

Improvements and equipment additions.

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- Definition

Real estate investment property accumulated depreciation additions during period.

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Real estate net increase decrease in construction in progress.

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Amount of decrease in accumulated depreciation, depletion and amortization as a result of sale or disposal of property, plant and equipment.

+ References

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Amount of divestiture of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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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))
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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 https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910

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