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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 |  |  |

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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 30 -Paragraph 8 -SubTopic 30 -Topic 805 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479637/805-30-30-8 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b) -SubTopic 30 -Topic 805 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479581/805-30-50-1 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 30 -Paragraph 7 -SubTopic 30 -Topic 805 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479637/805-30-30-7 + Details
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