Investment in Storage Facilities and Intangible Assets - Summary of Activity in Storage Facilities (Detail) $ in Thousands	9 Months Ended
Sep. 30, 2020 USD ($)
Cost:
Beginning balance	$ 4,749,473
Acquisition of storage facilities	413,022
Improvements and equipment additions	43,888
Net decrease in construction in progress	(5,884)
Dispositions	(247)
Ending balance	5,200,252
Accumulated Depreciation:
Beginning balance	756,333
Additions during the period	86,424
Dispositions	(165)
Ending balance	$ 842,592

Improvements and equipment additions.

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Real estate investment property accumulated depreciation additions during period.

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No definition available.

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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.

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No definition available.

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The capitalized costs incurred during the period (excluded from amortization) to purchase, lease or otherwise acquire an unproved property, including costs of lease bonuses and options to purchase or lease properties, the portion of costs applicable to minerals when land including mineral rights is purchased in fee, brokers' fees, recording fees, legal costs, and other costs incurred in acquiring properties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.4-10(c)(7)(ii))
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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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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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