Earnings Per Share / Unit (EPS / EPU) - Computation of Basic and Diluted EPS / EPU (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Numerator:
Net Income Available to Common Stockholders / Unitholders and Participating Securities	$ 55,967	$ 36,258
Net Income Allocable to Participating Securities	(47)	(31)
Net Income Available to Common Stockholders / Unitholders	$ 55,920	$ 36,227
Denominator:
Weighted Average Shares / Units - Basic	132,211	131,811
Performance Units (See Note 9) / Performance Units and certain Performance RLP Units (See Note 6)	88	74
Weighted Average Shares / Units - Diluted	132,299	131,885
Earnings Per Share/Unit, Basic [Abstract]
Net Income Available to Common Stockholders / Unitholders - Basic	$ 0.42	$ 0.27
Earnings Per Share/Unit, Diluted [Abstract]
Net Income Available to Common Stockholders / Unitholders - Diluted	$ 0.42	$ 0.27
First Industrial, L.P.
Numerator:
Net Income Available to Common Stockholders / Unitholders and Participating Securities	$ 57,394	$ 37,105
Net Income Allocable to Participating Securities	(134)	(88)
Net Income Available to Common Stockholders / Unitholders	$ 57,260	$ 37,017
Denominator:
Weighted Average Shares / Units - Basic	134,686	134,073
Performance Units (See Note 9) / Performance Units and certain Performance RLP Units (See Note 6)	545	422
Weighted Average Shares / Units - Diluted	135,231	134,495
Earnings Per Share/Unit, Basic [Abstract]
Net Income Available to Common Stockholders / Unitholders - Basic	$ 0.43	$ 0.28
Earnings Per Share/Unit, Diluted [Abstract]
Net Income Available to Common Stockholders / Unitholders - Diluted	$ 0.42	$ 0.28