Discontinued Operations (Details) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Condensed Statements of Income
Operating revenues and Earnings (losses) from unconsolidated affiliates	$ 3,684	$ 3,556	$ 101,966	$ 20,680
Income (loss) from discontinued operations
Income (loss) from discontinued operations	(8,534)	(8,864)	71,039	(13,432)
Gain (loss) on disposal of wholly owned assets			39,944
Less: income tax expense (benefit)	(1,294)	(1,273)	(3,513)	(511)
Income (loss) from discontinued operations, net of tax	$ (7,240)	$ (7,591)	$ 114,496	$ (12,921)

Overall income (loss) from a disposal group that is classified as a component of the entity, before income tax, reported as a separate component of income before extraordinary items. Includes the following (before income 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.

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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+ Details

- Definition

This element represents the overall income (loss) from a disposal group that is classified as a component of the entity, net of income tax, reported as a separate component of income before extraordinary items before deduction or consideration of the amount which may be allocable to noncontrolling interests, if any. Includes the following (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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