Accumulated Other Comprehensive Income (Changes in AOCI) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	$ 1,947,320	$ 1,798,263
Ending Balance	2,248,372	1,947,320
Derivative Instruments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(17,308)	(7,013)
Other Comprehensive Income (Loss), Before Reclassifications	6,146	(17,422)
Amounts Reclassified from Accumulated Other Comprehensive Loss	6,831	7,127
Net Current Period Other Comprehensive Income (Loss)	12,977	(10,295)
Ending Balance	(4,331)	(17,308)
Comprehensive Income (Loss) Attributable to Noncontrolling Interest of the Company
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	355	130
Other Comprehensive Income (Loss), Before Reclassifications	(262)	225
Amounts Reclassified from Accumulated Other Comprehensive Loss	0	0
Net Current Period Other Comprehensive Income (Loss)	(262)	225
Ending Balance	93	355
Accumulated Other Comprehensive Income (Loss) of the Company
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(16,953)	(6,883)
Other Comprehensive Income (Loss), Before Reclassifications	5,884	(17,197)
Amounts Reclassified from Accumulated Other Comprehensive Loss	6,831	7,127
Net Current Period Other Comprehensive Income (Loss)	12,715	(10,070)
Ending Balance	(4,238)	(16,953)
First Industrial, L.P. | Accumulated Other Comprehensive Income/Loss of the Operating Partnership
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(17,308)	(7,013)
Other Comprehensive Income (Loss), Before Reclassifications	6,146	(17,422)
Amounts Reclassified from Accumulated Other Comprehensive Loss	6,831	7,127
Net Current Period Other Comprehensive Income (Loss)	12,977	(10,295)
Ending Balance	$ (4,331)	$ (17,308)