v3.8.0.1

Income Taxes - Significant Components of Net Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Income Tax Disclosure [Abstract] |  |
Net operating loss carryforwards | $ 39,991 | $ 155,018
Derivative liabilities | 471 | 1,732
Other | 533 | 892
Total deferred tax assets | 40,995 | 157,642
Difference in depreciation, depletion and capitalization methods — oil and gas properties | (122,335) | (162,501)
Derivative assets | (302) |
Total deferred tax liabilities | (122,637) | (162,501)
Valuation allowance | (460) | (756)
Net deferred tax liability | $ (82,102) | $ (5,615)

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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 25 -Paragraph 20 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=96869850&loc=d3e28680-109314 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32621-109319 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32632-109319 + Details
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