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Earnings Per Share / Unit (EPS / EPU) - Additional Information (Details) - shares | Sep. 30, 2025 | Sep. 30, 2024
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Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] |  |
Unvested Restricted Stock / Unit Awards | 69,105 | 93,952
First Industrial, L.P. |  |
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] |  |
Unvested Restricted Stock / Unit Awards | 189,493 | 261,246

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