Area of land parcel held for sale.

No definition available.

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Namespace Prefix:	fr_
Data Type:	num:areaItemType
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Period Type:	duration

- Definition

Business acquisition purchase price allocation land parcel.

+ References

No definition available.

+ Details

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Namespace Prefix:	fr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Gross proceeds from the sale of industrial properties .

+ References

No definition available.

+ Details

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Namespace Prefix:	fr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Impairment loss of industrial properties and land parcels.

+ References

No definition available.

+ Details

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Namespace Prefix:	fr_
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Balance Type:	debit
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- Definition

Impairment reversal of industrial properties and land parcels.

+ References

No definition available.

+ Details

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Namespace Prefix:	fr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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- Definition

Number of industrial properties acquired.

+ References

No definition available.

+ Details

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- Definition

Number of industrial properties fair value measurements .

+ References

No definition available.

+ Details

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- Definition

Number of industrial properties sold.

+ References

No definition available.

+ Details

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Namespace Prefix:	fr_
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Balance Type:	na
Period Type:	duration

- Definition

Number of real estate properties included in discontinued operations .

+ References

No definition available.

+ Details

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- Definition

Number of industrial properties held for sale.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Number of land parcels held for sale .

+ References

No definition available.

+ Details

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- Definition

This is the acquisition of equity for a property within the 2003 net lease joint venture.

+ References

No definition available.

+ Details

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- Definition

Percentage of consideration paid of net fair value of acquisition.

+ References

No definition available.

+ Details

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

- Definition

Square footage industrial properties fair value measurements .

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Square footage of real estate property acquired.

+ References

No definition available.

+ Details

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Namespace Prefix:	fr_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	duration

- Definition

Square footage of real estate property held-for-sale.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Square footage of real estate property sold.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Amount of cash paid to acquire the entity.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph f(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Fair Value of the liabilities incurred by the acquirer to former owners of the acquiree, including the fair value of any contingent consideration. If liabilities transferred as consideration remain within the combined entity after the business combination (for example, because the assets or liabilities were transferred to the acquiree rather than to its former owners), and the acquirer therefore retains control of them; in that situation, the acquirer measures those liabilities at their carrying amounts immediately before the acquisition date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 25

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6405-128476

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph f(3)

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 39, 40, 41

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

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- Definition

The amount of acquisition cost of a business combination allocated to land and building to be used in the normal course of business, not including assets that are held-for-sale.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph e

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 37

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of gain (loss), before tax expense or benefit and not previously recognized, resulting from the sale of a business component.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 144

-Paragraph 47

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

-Paragraph 3

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 144

-Paragraph 43

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

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- Definition

The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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Balance Type:	credit
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- Definition

Amount of the excess of the fair value of acquired net assets over the cost of an acquired business after pro rata reduction of the amounts that otherwise would have been assigned to acquired assets except financial assets other than investments accounted for by the equity method, assets to be disposed of by sale, deferred tax assets, prepaid assets relating to pension and postretirement benefit plans, and other current assets. This amount is considered an extraordinary item and often referred to as negative goodwill. This element is gross of the related tax effect.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 44, 45, 46

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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Balance Type:	credit
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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. An amount representing an agreement for an unconditional promise by the maker to pay the Company (holder) a definite sum of money at a future date(s).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.3(b))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

-Subparagraph b

-Article 5

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- Definition

Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.3)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

-Article 5

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Disclosure of the unamortized amount of the discount on the note or receivable which is deducted from the face amount of the receivable or loan. The discount or premium is the difference between the present value and the face amount.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 1A

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

-Paragraph 16

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Investment in Real Estate (Details Textual) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2012 LandParcel IndustrialProperty	Jun. 30, 2011	Jun. 30, 2012 sqft acre IndustrialProperty LandParcel	Jun. 30, 2011 sqft IndustrialProperty	Dec. 31, 2011 IndustrialProperty
Investment in Real Estate (Textual) [Abstract]
Number of industrial properties acquired			1	1
Square footage of real estate property acquired			400,000	700,000
Percentage of consideration paid of net fair value of acquisition			85.00%	85.00%
Purchase price of industrial property	$ 21,819	$ 30,625	$ 21,819	$ 30,625
Carrying value of mortgage loan assumed from acquisition	12,026	24,417	12,026	24,417
Cash payment of acquisition	8,324	5,277	8,324	5,277
Approximate gain due to the difference between carrying value and fair value of acquisition			776	689
Purchase price of land parcel	46,675		46,675
Number of industrial properties sold			7
Square footage of real estate property sold			800,000
Gross proceeds from the sale of industrial properties			23,877
Gain on Sale of Real Estate			7,585	7,341
Gain on Sale of Real Estate Discontinued Operations	1,386	3,537	7,585	7,341
Number of industrial properties held for sale	16		16
Number of land parcels held for sale	1		1
Square footage of real estate property held for sale			3,200,000
Number of industrial properties included in discontinued operations				17	36
Notes receivable outstanding	47,228		47,228		55,502
Net discount of notes receivable outstanding	287		287		319
Fair value of notes receivable	52,024		52,024		58,734
Area of land parcel held for sale			55.9
Impairment loss of industrial properties and land parcels			52
Impairment reversal of industrial properties and land parcels				$ 10,507
3rd Party Pricing [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Number of industrial properties level 3 fair value measurements	5		5
Square footage of industrial properties level 3 fair value measurements	1,800,000		1,800,000
2003 Net Lease Joint Venture [Member]
Investment In Real Estate Other (Textual) [Abstract]
Equity interest acquired	85.00%	85.00%	85.00%	85.00%