Discontinued Operations (Predecessor) (Schedule of Assets and Liabilities Reclassified in Discontinued Operation) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Current assets associated with discontinued operations:
Current assets — discontinued operations	$ 0
Noncurrent assets
Total noncurrent assets	0
Current liabilities
Asset retirement obligations	0
Noncurrent liabilities
Total noncurrent liabilities	$ 0
Predecessor
Current assets associated with discontinued operations:
Current assets — discontinued operations		$ 5,195
Noncurrent assets
Total noncurrent assets		43,785
Current liabilities
Asset retirement obligations		15,419
Noncurrent liabilities
Total noncurrent liabilities		66,862
Non Stack Assets | Predecessor | Weeks Island Field, Louisiana | Disposed of by Sale
Current assets associated with discontinued operations:
Cash		61
Accounts receivable		4,980
Other receivables		154
Current assets — discontinued operations		5,195
Noncurrent assets
Investments		9,000
Proved oil and gas properties, net		33,618
Other long-term assets		1,167
Total noncurrent assets		43,785
Total assets associated with discontinued operations		48,980
Current liabilities
Accounts payable and accrued liabilities		7,882
Asset retirement obligations		7,537
Asset retirement obligations		15,419
Noncurrent liabilities
Asset retirement obligations, net of current portion		37,049
Founder Notes		28,166
Other long-term liabilities		1,647
Total noncurrent liabilities		66,862
Total liabilities associated with discontinued operations		$ 82,281