Discontinued Operations - Revenues and the components of income related to discontinued operations (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Revenues and the components of income related to discontinued operations: [Abstract]
Revenues		$ 90		$ 451
Loss from discontinued operations before income taxes		(121)		(2,470)
Benefit from income taxes		0		0
Loss from discontinued operations, net of taxes	$ 0	$ (121)	$ 0	$ (2,470)

Pretax income (loss) from operations of a business component (exclusive of any gain (loss) on disposal, or provision therefore) during the reporting period, until its disposal.

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After tax income (loss) from operations of a business component (exclusive of any gain (loss) on disposal, or provision therefore) during the reporting period, until its disposal.

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- Definition

Tax effect allocated to a disposal group that is classified as a component of the entity reported as a separate component of income before extraordinary items. Includes the tax effects of the following: 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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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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