Computation of Basic and Diluted Earnings Per Share (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Basic earnings per share:
Net income	$ 324	$ 433
Preferred dividends	(2,744)	(2,121)
Allocation to participating securities	(121)	(152)
Loss from operations attributable to non-controlling interests	(28)	5
Net loss applicable to the common stockholders	(2,569)	(1,835)
Net loss attributable to the common stockholders	(2,448)	(1,683)
Allocation to participating securities	(121)	(152)
Net loss applicable to the common stockholders	$ (2,569)	$ (1,835)
Weighted-average common shares outstanding:
Basic and diluted	45,352,489	37,761,446
Basic and diluted earnings per share:
Net loss per share attributable to the common stockholders	$ (0.06)	$ (0.06)

Net income loss available to common stock holders excluding participating securities.

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Amount of income (loss) from continuing operations attributable to the noncontrolling interest. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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The amount of net income (loss) before extraordinary items per each basic and diluted share of common stock or unit when the per share amount is the same for both basic and diluted shares.

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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