Share Based Compensation - Schedule of Valuation and Expense Information (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Share Based Compensation Allocation And Classification In Financial Statements [Abstract]
Total cost of share-based payment plans	$ 2,148	$ 10,276	$ 15,321	$ 46,166
Amounts capitalized in oil and gas properties and equipment	724	2,358	3,774	11,984
Amounts charged against income, before income tax benefit	1,424	7,918	11,547	34,182
Amount of related income tax benefit recognized in income before valuation allowance	$ 299	$ 3,151	$ 2,425	$ 13,604

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Amount of capitalized and expensed compensation cost from equity-based compensation arrangements.

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