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		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Numerator:
Net Income Available to Common Stockholders / Unitholders and Participating Securities	$ 116,991	$ 51,936	$ 153,249	$ 114,134
Net Income Allocable to Participating Securities	(103)	(61)	(134)	(122)
Net Income Available to Common Stockholders / Unitholders	$ 116,888	$ 51,875	$ 153,115	$ 114,012
Denominator:
Weighted Average Shares / Units - Basic	132,051	129,098	131,932	129,093
Performance Units (See Note 9) / Performance Units and certain Performance RLP Units (See Note 6)	55	89	65	86
Weighted Average Shares / Units - Diluted	132,106	129,187	131,997	129,179
Basic and Diluted Earnings Per Share / Unit:
Net Income Available to Common Stockholders / Unitholders - Basic	$ 0.89	$ 0.40	$ 1.16	$ 0.88
Net Income Available to Common Stockholders / Unitholders - Diluted	$ 0.88	$ 0.40	$ 1.16	$ 0.88
First Industrial, L.P.
Numerator:
Net Income Available to Common Stockholders / Unitholders and Participating Securities	$ 119,419	$ 53,140	$ 156,524	$ 116,705
Net Income Allocable to Participating Securities	(269)	(155)	(357)	(315)
Net Income Available to Common Stockholders / Unitholders	$ 119,150	$ 52,985	$ 156,167	$ 116,390
Denominator:
Weighted Average Shares / Units - Basic	134,278	131,188	134,176	131,180
Performance Units (See Note 9) / Performance Units and certain Performance RLP Units (See Note 6)	312	516	367	489
Weighted Average Shares / Units - Diluted	134,590	131,704	134,543	131,669
Basic and Diluted Earnings Per Share / Unit:
Net Income Available to Common Stockholders / Unitholders - Basic	$ 0.89	$ 0.40	$ 1.16	$ 0.89
Net Income Available to Common Stockholders / Unitholders - Diluted	$ 0.89	$ 0.40	$ 1.16	$ 0.88