Oil and Gas Properties - Schedule of Oil and Gas Properties (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Proven properties:
Acquisition, equipment, exploration, drilling and abandonment costs	$ 11,755,535	$ 11,577,281
Less: Accumulated depletion, depreciation and amortization	(10,178,996)	(10,079,554)
Total Oil and gas properties, net	$ 1,576,539	$ 1,497,727

Oil and gas properties, net of depletion, carried under the full cost method.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant