Investment in Real Estate - Summary Regarding Industrial Properties Included in Discontinued Operations (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Investment in Real Estate [Abstract]
Total Revenues	$ 1,009	$ 4,015
Property Expenses	(244)	(1,674)
Impairment of Real Estate	0	(1,410)
Depreciation and Amortization	(318)	(1,060)
(Loss) Gain on Sale of Real Estate	(3,074)	6,199
(Loss) Income from Discontinued Operations	$ (2,627)	$ 6,070

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 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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