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Compensation Plans Non Stock-Based Compensation (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Net Profits Plan [Member] |  |  |
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |
Minimum Percentage of Oil and Gas Wells, Costs Recovered for Payment to Employees from Net Profit Plan | 100.00% |  |
Percentage of Future Net Cash Flow Received by Participants from Net Profit Plan | 10.00% |  |
Percentage Of Future Net Cash Flow Received By Participants From Net Profit Plan Increased To | 20.00% |  |
Percentage of Oil and Gas Wells Costs Recovered for Additional Payment Employees from Net Profit Plan | 200.00% |  |
Cash Payments Made or Accrued under Profit Sharing Plan Allocated to General and Administrative Expense | $ 3,239,000 | $ 8,326,000 | $ 13,734,000
Cash Payments Made or Accrued under Profit Sharing Plan Allocated to Oil and Gas Exploration Expense | 259,000 | 690,000 | 1,310,000
Total Cash Payments, Made or Accrued under Profit Sharing Plan | 3,498,000 | 9,016,000 | 15,044,000
Cash Payments Made or Accrued under Profit Sharing Plan Related to Divested Property | $ 3,800,000 | 8,300,000 | 10,300,000
401K Plan [Member] |  |  |
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent | 60.00% |  |
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay, Employees Hired December 31, 2014 and Prior | 6.00% |  |
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay, Employees Hired After December 31, 2014 | 9.00% |  |
Defined Contribution Plan, Employer Matching Contribution, Percent of Bonus, Employees Hired December 31, 2014 and Prior | 6.00% |  |
Defined Contribution Plan, Employer Matching Contribution, Percent of Bonus, Employees Hired After December 31, 2014 | 9.00% |  |
Defined Contribution Plan, Cost Recognized | $ 5,600,000 | 6,400,000 | 4,200,000
Defined Contribution Plan, Employer Discretionary Contribution Amount | $ 0 | $ 0 | $ 0

X
- Definition Amount expensed to general and administrative expense related to cash payments made or accrued under the profit sharing plan. + References No definition available. + Details
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- Definition Amount expensed to oil and gas exploration expense related to cash payments made or accrued under the profit sharing plan. + References No definition available. + Details
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- Definition Cash payments made or accrued related to profit sharing plan liabilities arising from divested properties. + References No definition available. + Details
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- Definition Defined Contribution Plan, Employer Matching Contribution, Percent of Bonus, Employees Hired After December 31, 2014 + References No definition available. + Details
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- Definition Defined Contribution Plan, Employer Matching Contribution, Percent of Bonus, Employees Hired December 31, 2014 and Prior + References No definition available. + Details
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- Definition Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay, Employees Hired After December 31, 2014 + References No definition available. + Details
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- Definition Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay, Employees Hired December 31, 2014 and Prior + References No definition available. + Details
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- Definition Represents the minimum percentage of total costs required to be recovered for payment of net profit plan. + References No definition available. + Details
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- Definition Represents the percentage of future net cash payment to employees from the net profit plan. + References No definition available. + Details
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- Definition Represents the percentage of future net cash payment to employees from the net profit plan. + References No definition available. + Details
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- Definition Represents the percentage of total costs required to be recovered for additional payment from the net profit plan. + References No definition available. + Details
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- Definition Total amount expensed related to cash payments made or accrued under the profit sharing plan. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition The amount of the cost recognized during the period for defined contribution plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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- Definition Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan. + References No definition available. + Details
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