Investment in Real Estate - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014 Property sqft	Dec. 31, 2013 sqft Property	Dec. 31, 2012 Property Parcels sqft
Real Estate [Line Items]
Number of industrial properties acquired	8us-gaap_NumberOfBusinessesAcquired	2us-gaap_NumberOfBusinessesAcquired	1us-gaap_NumberOfBusinessesAcquired
Number of industrial properties acquired through acquisition of equity interest		1
Gross leasable area (GLA) of industrial properties acquired	1,100,000	1,100,000	400,000
Equity interest acquired		100.00%
Number of industrial properties owned	638us-gaap_NumberOfRealEstateProperties
Number of vacant industrial properties acquired		1
Purchase price of acquisitions	$ 95,692	$ 72,812	$ 21,819
Fair value of mortgage loan assumed from acquisition			12,026
Cash payment of acquisition			8,324
Percentage of consideration paid of net fair value of acquisition			85.00%
Gain on Change in Control of Interests	0	0	776
Purchase price of land parcels	39,739	34,518	46,695
Number of industrial properties sold	29fr_NumberOfIndustrialPropertiesSold	67fr_NumberOfIndustrialPropertiesSold	28fr_NumberOfIndustrialPropertiesSold
Gross leasable area (GLA) of industrial properties sold	2,000,000	3,000,000	4,200,000
Number of land parcels sold			1fr_NumberOfLandParcelsSold
Proceeds from sale of industrial properties	102,596us-gaap_ProceedsFromSaleOfBuildings	144,628us-gaap_ProceedsFromSaleOfBuildings	85,561us-gaap_ProceedsFromSaleOfBuildings
Gain on sale of real estate	25,905us-gaap_GainLossOnSaleOfProperties	35,444us-gaap_GainLossOnSaleOfProperties	16,442us-gaap_GainLossOnSaleOfProperties
Gain on sale of real estate included in discontinued operations	25,988	34,344	12,665
Number of sold industrial properties included in discontinued operations	29	67	28
Notes receivable outstanding	2,731us-gaap_NotesReceivableNet	52,605us-gaap_NotesReceivableNet
Net discount of notes receivable outstanding	0	191
interest rate of notes receivable	4.75%
Fair value of notes receivable	$ 2,732	$ 53,482
2003 Net Lease Joint Venture
Real Estate [Line Items]
Equity interest acquired			85.00%
Number of industrial properties owned	1		1

Number of Acquired Industrial Properties Vacant

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Number of industrial properties sold.

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- Definition

Number of Industrial Properties With Wholly Owned Equity Interest

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- Definition

Number Of Land Parcels Sold

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The number of sold industrial properties included in discontinued operations.

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Percentage of consideration paid of net fair value of acquisition.

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- Definition

Square footage of industrial properties sold.

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- Definition

Square Footage of Real Estate Properties Acquired.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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-SubTopic 10

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- Definition

Amount of long-term debt due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

+ References

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- Definition

Amount of real estate acquired, at the acquisition date.

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- Definition

Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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- Definition

In a business combination achieved in stages, this element represents the amount of gain recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

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- Definition

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

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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.

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- Definition

Fair value portion of an agreement for an unconditional promise by the maker to pay the holder a definite sum of money at a future date.

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-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.

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- Definition

The number of businesses acquired by the entity during the period.

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- Definition

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

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No definition available.

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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-Glossary Investing Activities

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- Definition

The cash inflow from sale of buildings.

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- Definition

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.

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Yield on the receivable, on which interest has been imputed, as calculated from its issuance value or purchase price. The calculated effective interest rate considers factors such as the issued face value or price paid for the receivable, the time period between payments, and the time until maturity [full receipt] of the receivable.

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