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		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Numerator:
Net Income Available to Common Stockholders / Unitholders	$ 65,269	$ 99,287	$ 168,486	$ 218,971
Denominator:
Weighted Average Shares / Units - Basic	132,450	132,370	132,432	132,366
Performance Units (See Note 9) / Performance Units and certain Performance RLP Units (See Note 6)	54	51	60	43
Weighted Average Shares / Units - Diluted	132,504	132,421	132,492	132,409
Earnings Per Share/Unit, Basic [Abstract]
Net Income Available to Common Stockholders / Unitholders - Basic	$ 0.49	$ 0.75	$ 1.27	$ 1.65
Earnings Per Share/Unit, Diluted [Abstract]
Net Income Available to Common Stockholders / Unitholders - Diluted	$ 0.49	$ 0.75	$ 1.27	$ 1.65
First Industrial, L.P.
Numerator:
Net Income Available to Common Stockholders / Unitholders	$ 67,188	$ 101,864	$ 173,422	$ 224,606
Denominator:
Weighted Average Shares / Units - Basic	135,479	135,099	135,461	135,088
Performance Units (See Note 9) / Performance Units and certain Performance RLP Units (See Note 6)	441	375	512	303
Weighted Average Shares / Units - Diluted	135,920	135,474	135,973	135,391
Earnings Per Share/Unit, Basic [Abstract]
Net Income Available to Common Stockholders / Unitholders - Basic	$ 0.50	$ 0.75	$ 1.28	$ 1.66
Earnings Per Share/Unit, Diluted [Abstract]
Net Income Available to Common Stockholders / Unitholders - Diluted	$ 0.49	$ 0.75	$ 1.28	$ 1.66