Discontinued Operations - Income Statement and Balance Sheet (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
Revenues	$ 0	$ 76,057	$ 0	$ 155,387
Operating expenses	0	(66,891)	0	(141,922)
Other loss, net	0	(197)	0	(429)
Income from discontinued operations before income taxes	0	8,969	0	13,036
Loss on sale of discontinued operations before income taxes	0	(38,525)	0	(38,525)
Discontinued operations, before income taxes	0	(29,556)	0	(25,489)
Income tax benefit	0	9,581	0	8,036
Discontinued operations, net of income taxes	$ 0	$ (19,975)	$ 0	$ (17,453)

Amount before tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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Amount before tax of income (loss) from a discontinued operation. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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Amount before tax of income (loss) from operations classified as a discontinued operation. Excludes gain (loss) on disposal and provision for gain (loss) until its disposal.

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Amount of tax expense (benefit) related to a discontinued operation. Includes, but is not limited to, tax expense (benefit) related to income (loss) from operations during the phase-out period, tax expense (benefit) related to gain (loss) on disposal, tax expense (benefit) related to gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and tax expense (benefit) related to adjustments of a prior period gain (loss) on disposal.

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Amount of operating expense attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of other expense attributable to disposal group, including, but not limited to, discontinued operation.

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Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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