Investment in Real Estate - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	1 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2012 Property	Sep. 30, 2012 sqft Parcels Property	Sep. 30, 2011 Property sqft	Dec. 31, 2011 Property
Real Estate Investments [Line Items]
Number of industrial properties acquired		1	1
Square footage of real estate property acquired		400,000	700,000
Purchase price of industrial property	$ 21,819	$ 21,819	$ 30,625
Carrying value of mortgage loan assumed from acquisition	12,026	12,026	24,417
Cash payment of acquisition	8,324	8,324	5,277
Percentage of consideration paid of net fair value of acquisition		85.00%	85.00%
Approximate gain due to the difference between carrying value and fair value of acquisition		776	689
Purchase price of land parcels	46,675	46,675
Number of industrial properties sold		25
Square footage of real estate property sold		4,100,000
Gross proceeds from the sale of industrial properties and land parcel		80,374
Number of Land Parcels Sold		1
Gain on Sale of Real Estate		15,782	14,721
Number of industrial properties held for sale	4	4
Square footage of real estate property held for sale		200,000
Number of industrial properties included in discontinued operations			30	36
Notes receivable outstanding	41,324	41,324		55,502
Net discount of notes receivable outstanding	271	271		319
Fair value of notes receivable	44,350	44,350		58,734
Mortgage loan receivable, outstanding	7,693	7,693
Unamortized discount on mortgage loan receivable	271	271
Carrying value of mortgage loan receivable	7,422	7,422
Number of industrial properties with mortgage loan receivable with bankrupt tenant	1
Impairment reversal of industrial properties and land parcels			11,116
Discontinuing Operations [Member]
Real Estate Investments [Line Items]
Gain on Sale of Real Estate		$ 12,005
2003 Net Lease Joint Venture [Member]
Real Estate Investments [Line Items]
Number of industrial properties acquired		1
Equity interest acquired	85.00%	85.00%	85.00%

Business acquisition purchase price allocation land parcel.

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- Definition

Gross proceeds from the sale of industrial properties .

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Impairment reversal of industrial properties and land parcels.

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Number of industrial properties acquired.

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No definition available.

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- Definition

Number of industrial properties sold.

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No definition available.

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- Definition

Number Of Industrial Properties With Mortgage Loan Receivable With Bankrupt Tenant

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Number Of Land Parcels Sold

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Number of real estate properties included in discontinued operations .

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No definition available.

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Number of industrial properties held for sale.

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No definition available.

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- Definition

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

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No definition available.

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Percentage of consideration paid of net fair value of acquisition.

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Square footage of real estate property acquired.

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

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Square footage of real estate property sold.

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Unamortized Discounts Net

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Amount of cash paid to acquire the entity.

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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.

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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.

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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

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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

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 44, 45, 46

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- Definition

The carrying amount of the outstanding balance due under the mortgage loan.

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-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph c

-Subparagraph Schedule IV

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- Definition

Amount of the contractual principal due at the origination of the mortgage loan (face amount).

+ References

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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).

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

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-Article 5

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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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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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