| Cover Page | Jul. 15, 2020 |
| Entity Information [Line Items] | |
| Document Type | 8-K |
| Document Period End Date | Jul. 15, 2020 |
| Entity Registrant Name | FIRST INDUSTRIAL REALTY TRUST, INC. |
| Entity Central Index Key | 0000921825 |
| Amendment Flag | false |
| Entity Incorporation, State or Country Code | MD |
| Entity File Number | 1-13102 |
| Entity Tax Identification Number | 36-3935116 |
| Entity Address, Address Line One | One North Wacker Drive, Suite 4200 |
| Entity Address, City or Town | Chicago |
| Entity Address, State or Province | IL |
| Entity Address, Postal Zip Code | 60606 |
| City Area Code | 312 |
| Local Phone Number | 344-4300 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock |
| Trading Symbol | FR |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
| First Industrial, L.P. | |
| Entity Information [Line Items] | |
| Document Type | 8-K |
| Document Period End Date | Jul. 15, 2020 |
| Entity Registrant Name | FIRST INDUSTRIAL, L.P. |
| Entity Central Index Key | 0001033128 |
| Amendment Flag | false |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 333-21873 |
| Entity Tax Identification Number | 36-3924586 |
| Entity Address, Address Line One | One North Wacker Drive, Suite 4200 |
| Entity Address, City or Town | Chicago |
| Entity Address, State or Province | IL |
| Entity Address, Postal Zip Code | 60606 |
| City Area Code | 312 |
| Local Phone Number | 344-4300 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
