Organization and Formation of Company - Additional Information (Detail)	Dec. 31, 2014 Property sqft	Dec. 31, 2012 Property
Organization and Formation of Company [Line Items]
Company's ownership interest in the general partners	100.00%fr_OwnershipInterestInGeneralPartner
Number of joint ventures	2fr_NumberOfJointVentures
Number of industrial properties owned	638us-gaap_NumberOfRealEstateProperties
Number of states in which industrial properties are located	25
Gross leasable area (GLA) of industrial properties owned	63,500,000us-gaap_AreaOfRealEstateProperty
2003 Net Lease Joint Venture
Organization and Formation of Company [Line Items]
Noncontrolling equity ownership interest	15.00%
Number of industrial properties owned	1	1
Gross leasable area (GLA) of industrial properties owned	800,000
2007 Europe Joint Venture
Organization and Formation of Company [Line Items]
Noncontrolling equity ownership interest	10.00%

The number of joint ventures that the entity owns a non-controlling interest in as of the balance sheet date.

No definition available.

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- Details

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- Definition

Ownership interest in general partner.

+ References

No definition available.

+ Details

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Namespace Prefix:	fr_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Area of a real estate property.

+ References

No definition available.

+ Details

Name:	us-gaap_AreaOfRealEstateProperty
Namespace Prefix:	us-gaap_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	instant

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

+ Details

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- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

The number of states the entity operates in as of the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Details

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- Details

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