v3.8.0.1
Document and Entity Information - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2017
Feb. 22, 2018
Jun. 30, 2017
Entity Information [Line Items]      
Document Type 10-K    
Amendment Flag false    
Document Period End Date Dec. 31, 2017    
Document Fiscal Year Focus 2017    
Document Fiscal Period Focus FY    
Trading Symbol FR    
Entity Registrant Name FIRST INDUSTRIAL REALTY TRUST INC    
Entity Central Index Key 0000921825    
Current Fiscal Year End Date --12-31    
Entity Well-known Seasoned Issuer Yes    
Entity Current Reporting Status Yes    
Entity Voluntary Filers No    
Entity Filer Category Large Accelerated Filer    
Entity Common Stock, Shares Outstanding   120,167,509  
Entity Public Float     $ 3,374.2
First Industrial, L.P.      
Entity Information [Line Items]      
Document Type 10-K    
Amendment Flag false    
Document Period End Date Dec. 31, 2017    
Document Fiscal Year Focus 2017    
Document Fiscal Period Focus FY    
Trading Symbol FRFI    
Entity Registrant Name FIRST INDUSTRIAL LP    
Entity Central Index Key 0001033128    
Current Fiscal Year End Date --12-31    
Entity Well-known Seasoned Issuer Yes    
Entity Current Reporting Status Yes    
Entity Voluntary Filers No    
Entity Filer Category Accelerated Filer