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, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Numerator:
Net Income Available to Common Stockholders / Unitholders and Participating Securities	$ 123,888	$ 42,446	$ 277,137	$ 156,580
Net Income Allocable to Participating Securities	(124)	(48)	(258)	(170)
Net Income Available to Common Stockholders / Unitholders	$ 123,764	$ 42,398	$ 276,879	$ 156,410
Denominator:
Weighted Average Shares / Units - Basic	132,092	129,633	131,986	129,275
Performance Units (See Note 9) / Performance Units and certain Performance RLP Units (See Note 6)	84	89	71	87
Weighted Average Shares / Units - Diluted	132,176	129,722	132,057	129,362
Earnings Per Share/Unit, Basic [Abstract]
Net Income Available to Common Stockholders / Unitholders - Basic	$ 0.94	$ 0.33	$ 2.10	$ 1.21
Earnings Per Share/Unit, Diluted [Abstract]
Net Income Available to Common Stockholders / Unitholders - Diluted	$ 0.94	$ 0.33	$ 2.10	$ 1.21
First Industrial, L.P.
Numerator:
Net Income Available to Common Stockholders / Unitholders and Participating Securities	$ 126,789	$ 43,399	$ 283,313	$ 160,104
Net Income Allocable to Participating Securities	(307)	(126)	(664)	(441)
Net Income Available to Common Stockholders / Unitholders	$ 126,482	$ 43,273	$ 282,649	$ 159,663
Denominator:
Weighted Average Shares / Units - Basic	134,282	131,668	134,212	131,345
Performance Units (See Note 9) / Performance Units and certain Performance RLP Units (See Note 6)	479	510	404	496
Weighted Average Shares / Units - Diluted	134,761	132,178	134,616	131,841
Earnings Per Share/Unit, Basic [Abstract]
Net Income Available to Common Stockholders / Unitholders - Basic	$ 0.94	$ 0.33	$ 2.11	$ 1.22
Earnings Per Share/Unit, Diluted [Abstract]
Net Income Available to Common Stockholders / Unitholders - Diluted	$ 0.94	$ 0.33	$ 2.10	$ 1.21