Properties and Equipment, Net - Summary of Assets Held for Sale (Details) - Assets Held for Sale $ in Thousands	Jun. 30, 2017 USD ($)
ASSETS
Inventories	$ 2,228
Properties and equipment, net	104,518
Deferred income taxes	6,803
Assets	113,549
LIABILITIES
Asset retirement obligations	75,693
Liabilities	75,693
Net assets	$ 37,856

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Disposal Group, Including Discontinued Operation, Net Assets

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Amount classified as assets attributable to disposal group held for sale or disposed of.

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Amount classified as deferred tax assets attributable to disposal group held for sale or disposed of.

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