Assets Held for Sale and Discontinued Operations - Summary of Results of Operations for Discontinued Operations (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Discontinued Operations And Disposal Groups [Abstract]
Revenues	$ 949
Depreciation, depletion, amortization and accretion	(52)
Other operating expenses	(1,079)
Loss from discontinued operations, net of tax	(182)
Loss from discontinued operations, net of tax	$ (182)

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

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Amount of depreciation and amortization 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 of revenue attributable to disposal group, including, but not limited to, discontinued operation.

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