Acquisitions and Divestitures - Arkoma Divestiture - Assets Held for Sale - Balance Sheet Data (Details) $ in Thousands	Jun. 30, 2017 USD ($)
Assets:
Total current assets held for sale	$ 3,455
Liabilities:
Total current liabilities related to assets held for sale	7,472
Disposal Group, Held-for-sale, Not Discontinued Operations
Assets:
Oil and gas sales	3,250
Joint interest owners	102
Other	14
Other current assets	4
Less: Accumulated depreciation and amortization	(10)
Other property, plant and equipment, net	85
Total current assets held for sale	3,455
Unproved	12,204
Proved	216,570
Wells and equipment and related facilities	179,925
Less: Accumulated depletion and impairment	(344,499)
Oil and gas properties, net	64,200
Total assets held for sale, net	67,655
Liabilities:
Trade accounts payable	379
Oil and gas sales payable	6,015
Accrued liabilities	1,078
Total current liabilities related to assets held for sale	7,472
Asset retirement obligations	1,143
Total liabilities related to assets held for sale	8,615
Disposal Group, Held-for-sale, Not Discontinued Operations | Leasehold improvements
Assets:
Other property, plant and equipment, gross	27
Disposal Group, Held-for-sale, Not Discontinued Operations | Other
Assets:
Other property, plant and equipment, gross	$ 68