Discontinued Operations (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013
Discontinued Operations
Operating revenues	$ 3,690
Operating expenses	(3,686)
Interest expense	(99)
Loss on extinguishment of debt	(3,115)
Gain on sale of assets	51,620
Income from discontinued operations	$ 48,410

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 interest expense allocated to disposal group, including a discontinued operation.

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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 other expense attributable to disposal group.

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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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