Earnings Per Share / Unit (EPS / EPU) - Computation of Basic and Diluted EPS / EPU (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Numerator:
Income from Continuing Operations									$ 76,705	$ 23,182	$ 4,862
Noncontrolling Interest Allocable to Continuing Operations									(2,903)	(813)	396
Income from Continuing Operations Allocable to Participating Securities	$ (153)	$ (50)	$ (50)	$ (41)	$ (32)	$ (33)	$ (32)	$ (18)	(248)	(75)	0
Income (Loss) from Continuing Operations Attributable to Common Stockholder / Unitholders									73,554	22,294	5,258
Preferred Dividends/Unit Distributions					0	0	0	(1,019)	0	(1,019)	(8,733)
Redemption of Preferred Stock/Units					0	0	0	(1,462)	0	(1,462)	(5,667)
Income (Loss) from Continuing Operations Available to First Industrial Realty Trust, Inc.’s Common Stockholders									73,554	19,813	(9,142)
Income from Discontinued Operations					11,246	13,389	1,011	1,095	0	27,823	36,566
Noncontrolling Interest Allocable to Discontinued Operations									0	(1,082)	(1,517)
Income from Discontinued Operations Allocable to Participating Securities					(47)	(57)	(11)	(14)	0	(100)	(162)
Income from Discontinued Operations Attributable to Common Stockholders / Unitholders									0	26,641	34,887
Net Income (Loss) Available to Common Stockholders/Unitholders and Participating Securities	$ 43,500	$ 13,917	$ 14,012	$ 2,373	$ 18,781	$ 21,327	$ 4,039	$ 2,482	73,802	46,629	25,907
Net Income Allocable to Participating Securities									(248)	(175)	(162)
Net Income Available to First Industrial Realty Trust, Inc.’s Common Stockholders									$ 73,554	$ 46,454	$ 25,745
Denominator:
Weighted Average Shares/Units - Basic	110,392	110,356	110,348	110,310	110,118	110,072	109,815	109,676	110,352	109,922	106,995
LTIP Unit Awards									429	403	0
Weighted Average Shares/Units - Diluted	110,916	110,848	110,683	110,675	110,405	110,271	110,404	110,215	110,781	110,325	106,995
Basic Earnings Per Share/Unit:
Income (Loss) from Continuing Operations Available to Common Stockholders / Unitholders					$ 0.07	$ 0.07	$ 0.03	$ 0.01	$ 0.67	$ 0.18	$ (0.09)
Income (Loss) from Discontinued Operations Attributable to Common Stockholders / Unitholders					0.10	0.12	0.01	0.01	0.00	0.24	0.33
Net Income Available to Common Stockholders/Unitholders	$ 0.39	$ 0.13	$ 0.13	$ 0.02	0.17	0.19	0.04	0.02	0.67	0.42	0.24
Diluted Earnings Per Share/Unit:
Income (Loss) from Continuing Operations Available to Common Stockholders / Unitholders					0.07	0.07	0.03	0.01	0.66	0.18	(0.09)
Income (Loss) from Discontinued Operations Attributable to Common Stockholders / Unitholders					0.10	0.12	0.01	0.01	0.00	0.24	0.33
Net Income Available to Common Stockholders / Unitholders	$ 0.39	$ 0.13	$ 0.13	$ 0.02	$ 0.17	$ 0.19	$ 0.04	$ 0.02	$ 0.66	$ 0.42	$ 0.24
First Industrial L.P.
Numerator:
Income from Continuing Operations									$ 76,820	$ 23,434	$ 4,908
Noncontrolling Interest Allocable to Continuing Operations									(138)	(62)	(36)
Income from Continuing Operations Allocable to Participating Securities	$ (153)	$ (50)	$ (50)	$ (41)	$ (32)	$ (33)	$ (32)	$ (17)	(248)	(75)	0
Income (Loss) from Continuing Operations Attributable to Common Stockholder / Unitholders									76,434	23,297	4,872
Preferred Dividends/Unit Distributions					0	0	0	(1,019)	0	(1,019)	(8,733)
Redemption of Preferred Stock/Units					0	0	0	(1,462)	0	(1,462)	(5,667)
Income (Loss) from Continuing Operations Available to Unitholders									76,434	20,816	(9,528)
Income from Discontinued Operations					11,698	13,924	1,051	1,140	0	27,823	36,566
Noncontrolling Interest Allocable to Discontinued Operations									0	(10)	(5)
Income from Discontinued Operations Allocable to Participating Securities					(47)	(57)	(11)	(14)	0	(100)	(162)
Income from Discontinued Operations Attributable to Common Stockholders / Unitholders									0	27,713	36,399
Net Income (Loss) Available to Common Stockholders/Unitholders and Participating Securities	$ 45,143	$ 14,438	$ 14,644	$ 2,457	$ 19,662	$ 22,218	$ 4,227	$ 2,597	76,682	48,704	27,033
Net Income Allocable to Participating Securities									(248)	(175)	(162)
Net Income Available to Unitholders									$ 76,434	$ 48,529	$ 26,871
Denominator:
Weighted Average Shares/Units - Basic	114,722	114,720	114,712	114,681	114,512	114,512	114,278	114,245	114,709	114,388	111,646
LTIP Unit Awards									429	403	0
Weighted Average Shares/Units - Diluted	115,246	115,212	115,047	115,046	114,799	114,711	114,867	114,784	115,138	114,791	111,646
Basic Earnings Per Share/Unit:
Income (Loss) from Continuing Operations Available to Common Stockholders / Unitholders					$ 0.07	$ 0.07	$ 0.03	$ 0.01	$ 0.67	$ 0.18	$ (0.09)
Income (Loss) from Discontinued Operations Attributable to Common Stockholders / Unitholders					0.10	0.12	0.01	0.01	0.00	0.24	0.33
Net Income Available to Common Stockholders/Unitholders	$ 0.39	$ 0.13	$ 0.13	$ 0.02	0.17	0.19	0.04	0.02	0.67	0.42	0.24
Diluted Earnings Per Share/Unit:
Income (Loss) from Continuing Operations Available to Common Stockholders / Unitholders					0.07	0.07	0.03	0.01	0.66	0.18	(0.09)
Income (Loss) from Discontinued Operations Attributable to Common Stockholders / Unitholders					0.10	0.12	0.01	0.01	0.00	0.24	0.33
Net Income Available to Common Stockholders / Unitholders	$ 0.39	$ 0.12	$ 0.13	$ 0.02	$ 0.17	$ 0.19	$ 0.04	$ 0.02	$ 0.66	$ 0.42	$ 0.24