Investment in Real Estate - Summary Regarding Industrial Properties Included in Discontinued Operations (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Real Estate [Abstract]
Total Revenues		$ 2,360
Property Expenses		(1,038)
Depreciation and Amortization		(916)
Gain on Sale of Real Estate	0	735
Income from Discontinued Operations	$ 0	$ 1,141

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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Amount of depreciation and amortization attributable to disposal group.

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Amount of operating expenses attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

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Amount of sales or other form of revenues attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

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Amount of income (loss) from a disposal group, net of income tax before extraordinary items allocable to noncontrolling interests. Includes, net of tax, income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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