Discontinued Operations - Discontinued Operations (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Discontinued Operations And Disposal Groups [Abstract]
Revenues	$ 62	$ 2,750	$ 531	$ 5,459
Gain (loss) on sale	2,054	(1,446)	2,054	(1,446)
Income	$ 2,100	$ 368	$ 2,461	$ 2,407
Earnings per share/unit - diluted	$ 0.01		$ 0.02	$ 0.02

Amount of gain (loss), after tax expense or benefit and not previously recognized, resulting from the sale of a business component.

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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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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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.

+ References

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Per diluted share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation.

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