Equity of the Company and Partners' Capital of the Operating Partnership - Common Stock and Units Roll-Forward (Details) - shares	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Class of Stock [Line Items]
Common Stock/Units, Outstanding, Beginning Balance	132,349,119
Limited Partners' Capital Account, Units Retired		4,429	330
Common Stock/Units, Outstanding, Ending Balance	132,470,326	132,349,119
Common Stock / Operating Partnership Units
Class of Stock [Line Items]
Common Stock/Units, Outstanding, Beginning Balance	132,349,119	132,289,039	132,141,503
Issuance of Restricted Stock/Awards	0	0	0
Vesting of Performance Units	59,686	56,646	73,840
Repurchase and Retirement of Restricted Stock/Awards	0	0	0
Conversion of Limited Partner Units	61,521	3,434	73,696
Limited Partners' Capital Account, Units Retired		0	0
Common Stock/Units, Outstanding, Ending Balance	132,470,326	132,349,119	132,289,039
First Industrial, L.P. \| Common Stock / Operating Partnership Units
Class of Stock [Line Items]
Common Stock/Units, Outstanding, Beginning Balance	135,989,979	135,667,204	135,197,269
Issuance of Restricted Stock/Awards	549,203	396,400	405,618
Vesting of Performance Units	59,686	56,646	73,840
Repurchase and Retirement of Restricted Stock/Awards	(97,454)	(125,842)	(9,193)
Conversion of Limited Partner Units	0	0	0
Limited Partners' Capital Account, Units Retired		(4,429)	(330)
Common Stock/Units, Outstanding, Ending Balance	136,501,414	135,989,979	135,667,204

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