Organization and Description of Business (Details) ft² in Millions	3 Months Ended	9 Months Ended
Mar. 31, 2025	Sep. 30, 2025 ft² building state
Real Estate Properties [Line Items]
Number of properties \| building		601
Number of states in which the entity owned buildings \| state		41
Area (in square feet) \| ft²		119.2
STAG Industrial, Inc. [Member]
Real Estate Properties [Line Items]
Ownership interest in Operating Partnership (as a percent)	98.00%	98.00%

Area of a real estate property.

No definition available.

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- Definition

Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482987/272-10-50-3

+ Details

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- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

The number of states the entity operates in as of the balance sheet date.

+ References

No definition available.

+ Details

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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

No definition available.

+ Details

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- Details

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