Number of land parcels developed into self storage facilities.

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Number of real estate ventures.

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Number Of Self Storage Facilities

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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.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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A deposit made by a purchaser of real estate to evidence good faith. It is customary for a buyer to give the seller earnest money at the time a sales contract is signed. The earnest money generally is credited to the down payment at closing, which is applied at closing as a component of payment against the purchase price.

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Fair value of equity issued in a business combination.

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Number of shares of stock issued during the period pursuant to acquisitions.

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Real Estate - Additional Information (Detail) shares in Millions, $ in Millions					12 Months Ended
	Mar. 12, 2025 USD ($) Landparcel StorageFacility	Jun. 01, 2022 USD ($) StorageFacility RealEstateVenture	Dec. 30, 2021 Storagefacility	Mar. 17, 2021 RealEstateVenture StorageFacility shares	Dec. 31, 2024 StorageFacility
Business Acquisition [Line Items]
Number of self storage facilities			2		161
Canada \| Subsequent Event [Member]
Business Acquisition [Line Items]
Number of land parcel developed into self storage facilities \| Landparcel	1
Self Storage Facilities [Member] \| Subsequent Event [Member]
Business Acquisition [Line Items]
Number of self storage facilities \| StorageFacility	3
Consideration transferred \| $	$ 61.1
Forfeit earnest money \| $	$ 2.3
SST IV Merger Agreement
Business Acquisition [Line Items]
Number of self storage facilities \| StorageFacility				24
Percentage of voting membership interest				50.00%
SST IV Merger Agreement \| Class A Common stock
Business Acquisition [Line Items]
Issuance of common stock in connection with SST IV Merger (in shares) \| shares				5.8
SST IV Merger Agreement \| Canada
Business Acquisition [Line Items]
Number of unconsolidated real estate ventures \| RealEstateVenture				6
SSGT II Merger Agreement
Business Acquisition [Line Items]
Number of self storage facilities \| StorageFacility		10
Percentage of voting membership interest		50.00%
SSGT II Merger Agreement \| Class A Common stock
Business Acquisition [Line Items]
Common stock issued \| $		$ 2.9
SSGT II Merger Agreement \| Canada
Business Acquisition [Line Items]
Number of unconsolidated real estate ventures \| RealEstateVenture		3