CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net Income	$ 31,499	$ 31,466
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities:
Depreciation	69,592	70,109
Amortization of Deferred Financing Costs	2,291	2,360
Other Amortization	21,205	23,476
Impairment of Real Estate	626	0
Provision for Bad Debt	748	1,069
Equity in Income of Joint Ventures	(61)	(3,508)
Distributions from Joint Ventures	0	1,881
Gain on Sale of Real Estate	(13,084)	(14,483)
Loss from Retirement of Debt	0	655
Mark-to-Market and Settlement Loss on Interest Rate Protection Agreements	11,546	0
Increase in Tenant Accounts Receivable, Prepaid Expenses and Other Assets, Net	(3,897)	(4,369)
Increase in Deferred Rent Receivable	(5,325)	(1,224)
Increase (Decrease) in Accounts Payable, Accrued Expenses, Other Liabilities, Rents Received in Advance and Security Deposits	5,550	(919)
Payments of Discounts and Prepayment Penalties Associated with Retirement of Debt	0	(10,650)
Net Cash Provided by Operating Activities	120,690	95,863
CASH FLOWS FROM INVESTING ACTIVITIES:
Acquisitions of Real Estate	(73,179)	(53,211)
Additions to Investment in Real Estate and Non-Acquisition Tenant Improvements and Lease Costs	(100,799)	(83,818)
Net Proceeds from Sales of Investments in Real Estate	48,393	56,622
Contributions to and Investments in Joint Ventures	(200)	(28)
Distributions from Joint Ventures	126	2,469
Settlement of Interest Rate Protection Agreements	(11,546)	0
Repayments of Notes Receivable	2,760	49,761
Increase in Escrows	(1,619)	(515)
Net Cash Used in Investing Activities	(136,064)	(28,720)
CASH FLOWS FROM FINANCING ACTIVITIES:
Debt and Equity Issuance and Redemption Costs	(4,882)	(2,411)
Repurchase and Retirement of Restricted Stock / Units	(2,101)	(4,667)
Common Stock and Unit Distributions Paid	(41,136)	(33,367)
Preferred Dividends Paid	0	(1,471)
Redemption of Preferred Stock / Units	0	(75,000)
Repayments on Mortgage Loans Payable	(9,054)	(74,944)
Repayments of Senior Unsecured Notes	0	(71,578)
Proceeds from Unsecured Term Loans	260,000	200,000
Proceeds from Unsecured Credit Facility	210,000	307,000
Repayments on Unsecured Credit Facility	(340,000)	(304,000)
Net Cash Provided by (Used in) Financing Activities	72,827	(60,438)
Net Effect of Exchange Rate Changes on Cash and Cash Equivalents	(14)	(23)
Net Increase in Cash and Cash Equivalents	57,453	6,705
Cash and Cash Equivalents, Beginning of Year	9,500	7,577
Cash and Cash Equivalents, End of Year	66,939	14,259
Supplemental Cash Flow Information [Abstract]
Interest Expense Capitalized in Connection with Development Activity	1,685	1,030
Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract]
Distribution Payable	15,096	11,886
Exchange Of Operating Partnership / Limited Partnership Units For Common Stock / General Partnership Units [Abstract]
Conversion of Units / Limited Partner Units to Common Stock / General Partner Units	0	0
Assumption of Liabilities in Connection with the Acquisition of Real Estate	608	294
Accounts Payable Related to Construction in Progress and Additions to Investment in Real Estate	20,355	23,785
Write-off of Fully Depreciated Assets	(28,609)	(29,090)
Noncontrolling Interest
CASH FLOWS FROM OPERATING ACTIVITIES:
Net Income	1,197
Exchange Of Operating Partnership / Limited Partnership Units For Common Stock / General Partnership Units [Abstract]
Conversion of Units / Limited Partner Units to Common Stock / General Partner Units	(106)	(1,697)
Common Stock
Exchange Of Operating Partnership / Limited Partnership Units For Common Stock / General Partnership Units [Abstract]
Conversion of Units / Limited Partner Units to Common Stock / General Partner Units	0	2
Additional Paid-in-Capital
Exchange Of Operating Partnership / Limited Partnership Units For Common Stock / General Partnership Units [Abstract]
Conversion of Units / Limited Partner Units to Common Stock / General Partner Units	106	1,695
First Industrial, L.P.
CASH FLOWS FROM OPERATING ACTIVITIES:
Net Income	31,614	31,573
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities:
Depreciation	69,592	70,109
Amortization of Deferred Financing Costs	2,291	2,360
Other Amortization	21,205	23,476
Impairment of Real Estate	626	0
Provision for Bad Debt	748	1,069
Equity in Income of Joint Ventures	(61)	(3,508)
Distributions from Joint Ventures	0	1,881
Gain on Sale of Real Estate	(13,084)	(14,483)
Loss from Retirement of Debt	0	655
Mark-to-Market and Settlement Loss on Interest Rate Protection Agreements	11,546	0
Increase in Tenant Accounts Receivable, Prepaid Expenses and Other Assets, Net	(3,982)	(3,894)
Increase in Deferred Rent Receivable	(5,325)	(1,224)
Increase (Decrease) in Accounts Payable, Accrued Expenses, Other Liabilities, Rents Received in Advance and Security Deposits	5,559	(915)
Payments of Discounts and Prepayment Penalties Associated with Retirement of Debt	0	(10,650)
Net Cash Provided by Operating Activities	120,729	96,449
CASH FLOWS FROM INVESTING ACTIVITIES:
Acquisitions of Real Estate	(73,179)	(53,211)
Additions to Investment in Real Estate and Non-Acquisition Tenant Improvements and Lease Costs	(100,799)	(83,818)
Net Proceeds from Sales of Investments in Real Estate	48,393	56,622
Contributions to and Investments in Joint Ventures	(200)	(28)
Distributions from Joint Ventures	126	2,469
Settlement of Interest Rate Protection Agreements	(11,546)	0
Repayments of Notes Receivable	2,760	49,761
Increase in Escrows	(1,619)	(770)
Net Cash Used in Investing Activities	(136,064)	(28,975)
CASH FLOWS FROM FINANCING ACTIVITIES:
Debt and Equity Issuance and Redemption Costs	(4,882)	(2,411)
Repurchase and Retirement of Restricted Stock / Units	(2,101)	(4,667)
Common Stock and Unit Distributions Paid	(41,136)	(33,367)
Preferred Dividends Paid	0	(1,471)
Redemption of Preferred Stock / Units	0	(75,000)
Contributions from Noncontrolling Interests	61	57
Distributions to Noncontrolling Interests	(85)	(388)
Repayments on Mortgage Loans Payable	(9,054)	(74,944)
Repayments of Senior Unsecured Notes	0	(71,578)
Proceeds from Unsecured Term Loans	260,000	200,000
Proceeds from Unsecured Credit Facility	210,000	307,000
Repayments on Unsecured Credit Facility	(340,000)	(304,000)
Net Cash Provided by (Used in) Financing Activities	72,803	(60,769)
Net Effect of Exchange Rate Changes on Cash and Cash Equivalents	(14)	(23)
Net Increase in Cash and Cash Equivalents	57,468	6,705
Cash and Cash Equivalents, Beginning of Year	9,485	7,562
Cash and Cash Equivalents, End of Year	66,939	14,244
Supplemental Cash Flow Information [Abstract]
Interest Expense Capitalized in Connection with Development Activity	1,685	1,030
Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract]
Distribution Payable	15,096	11,886
Exchange Of Operating Partnership / Limited Partnership Units For Common Stock / General Partnership Units [Abstract]
Conversion of Units / Limited Partner Units to Common Stock / General Partner Units	0	0
Assumption of Liabilities in Connection with the Acquisition of Real Estate	608	294
Accounts Payable Related to Construction in Progress and Additions to Investment in Real Estate	20,355	23,785
Write-off of Fully Depreciated Assets	(28,609)	(29,090)
First Industrial, L.P. | Noncontrolling Interest
CASH FLOWS FROM OPERATING ACTIVITIES:
Net Income	75
First Industrial, L.P. | Limited Partner Units
CASH FLOWS FROM OPERATING ACTIVITIES:
Net Income	1,197
Exchange Of Operating Partnership / Limited Partnership Units For Common Stock / General Partnership Units [Abstract]
Conversion of Units / Limited Partner Units to Common Stock / General Partner Units	(106)	(1,697)
First Industrial, L.P. | General Partner Units
CASH FLOWS FROM OPERATING ACTIVITIES:
Net Income	30,342
Exchange Of Operating Partnership / Limited Partnership Units For Common Stock / General Partnership Units [Abstract]
Conversion of Units / Limited Partner Units to Common Stock / General Partner Units	$ 106	$ 1,697