Investment in Real Estate - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2014 sqft Property	Mar. 31, 2013 Property	Dec. 31, 2013 Property
Real Estate Investment Property, Net [Abstract]
Number of industrial properties acquired	1
Gross leasable area (GLA) of industrial properties acquired	300,000
Purchase price of acquisitions	$ 13,400
Number of industrial properties sold	1
Gross leasable area (GLA) of industrial properties sold	30,000
Gain on sale of real estate	432	(2,812)
Number of sold properties included in discontinued operations	1	4	65
Proceeds from sale of industrial properties	1,335
Notes receivable outstanding	35,516		52,605
Net discount of notes receivable outstanding	0		191
Fair value of notes receivable	$ 37,482		$ 53,482

Number of industrial properties acquired.

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- Definition

Number of industrial properties sold.

+ References

No definition available.

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- Definition

The number of sold properties and the related gain or loss on sale of real estate included in discontinued operations.

+ References

No definition available.

+ Details

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- Definition

Square footage of industrial properties sold.

+ References

No definition available.

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- Definition

Square Footage of Real Estate Properties Acquired.

+ References

No definition available.

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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

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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.

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

-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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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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-Publisher FASB

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-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

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- Definition

The cash inflow from sale of buildings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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-Subparagraph (c)

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 1A

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