Statement of Financial Position [Abstract] Statement [Table] Statement [Table] Scenario [Axis] Scenario [Axis] Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Statement [Line Items] Statement [Line Items] Deferred Tax Assets, Net of Valuation Allowance, Noncurrent Deferred Tax Assets, Net of Valuation Allowance, Noncurrent ASSETS Assets [Abstract] Current assets: Assets, Current [Abstract] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Accounts receivable: Accounts Receivable, Net, Current [Abstract] Trade, net Accounts Receivable, Net, Current Due from affiliates Due from Affiliate, Current Income taxes receivable Income Taxes Receivable, Current Inventories Inventory, Net Prepaid expenses Prepaid Expense, Current Notes receivable Notes, Loans and Financing Receivable, Gross, Current Deferred income taxes Deferred Tax Assets, Net of Valuation Allowance, Current Assets held for sale Disposal Group, Including Discontinued Operation, Assets Other current assets: Other Assets, Current [Abstract] Other Assets, Current [Abstract] Derivatives Derivative Asset, Current Other Other Assets, Current Total current assets Assets, Current Property, plant and equipment, at cost: Property, Plant and Equipment, Net [Abstract] Oil and gas properties, using the successful efforts method of accounting: Oil and Gas Property, Successful Effort Method, Net [Abstract] Proved properties Proved Oil and Gas Property, Successful Effort Method Unproved properties Unproved Oil and Gas Property, Successful Effort Method Accumulated depletion, depreciation and amortization Oil and Gas Property, Successful Effort Method, Accumulated Depreciation, Depletion and Amortization Total property, plant and equipment Oil and Gas Property, Successful Effort Method, Net Goodwill Goodwill Property, Plant and Equipment, Net Property, Plant and Equipment, Net Other assets: Other Assets, Noncurrent [Abstract] Investment in unconsolidated affiliate Equity Method Investments Derivatives Derivative Asset, Noncurrent Other, net Other Assets, Noncurrent Assets, Total Assets LIABILITIES AND STOCKHOLDERS' EQUITY Liabilities and Equity [Abstract] Current liabilities: Liabilities, Current [Abstract] Accounts payable: Accounts Payable, Current [Abstract] Trade Accounts Payable, Trade, Current Due to affiliates Due to Affiliate, Current Interest payable Interest Payable, Current Income taxes payable Accrued Income Taxes, Current Deferred income taxes Deferred Tax Liabilities, Net, Current Liabilities held for sale Disposal Group, Including Discontinued Operation, Liabilities Other current liabilities: Other Liabilities, Current [Abstract] Long-term Debt, Current Maturities Long-term Debt, Current Maturities Derivatives Derivative Liability, Current Deferred revenue Deferred Revenue, Current Other Other Liabilities, Current Total current liabilities Liabilities, Current Long-term Debt, Excluding Current Maturities Long-term Debt, Excluding Current Maturities Derivatives Derivative Liability, Noncurrent Deferred income taxes Deferred Tax Liabilities, Net, Noncurrent Other liabilities Other Liabilities, Noncurrent Stockholders' equity: Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Common stock, $.01 par value Common Stock, Value, Issued Additional paid-in capital Additional Paid in Capital Treasury stock, at cost Treasury Stock, Value Retained earnings Retained Earnings (Accumulated Deficit) Accumulated other comprehensive income (loss) - net deferred hedge gains (losses), net of tax Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax Total stockholders' equity attributable to common stockholders Stockholders' Equity Attributable to Parent Noncontrolling interest in consolidating subsidiaries Stockholders' Equity Attributable to Noncontrolling Interest Total stockholders' equity Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Commitments and contingencies Commitments and Contingencies Liabilities and Stockholders' Equity, Total Liabilities and Equity Income Tax Disclosure [Abstract] Income Taxes Income Tax Disclosure [Text Block] Accounting Policies [Abstract] Schedule of Other Ownership Interests [Table] Schedule of Other Ownership Interests [Table] Adjustments for Change in Accounting Principle [Axis] Adjustments for Change in Accounting Principle [Axis] Adjustments for Change in Accounting Principle [Domain] Adjustments for Change in Accounting Principle [Domain] Adjustments for New Accounting Principle, Early Adoption [Member] Adjustments for New Accounting Principle, Early Adoption [Member] Cash [Member] Cash [Member] Deferred Compensation, Share-based Payments [Member] Deferred Compensation, Share-based Payments [Member] Leasehold Improvements [Member] Leasehold Improvements [Member] Property Subject to Operating Lease [Member] Property Subject to Operating Lease [Member] Restructuring Type [Axis] Restructuring Type [Axis] Type of Restructuring [Domain] Type of Restructuring [Domain] Employee Severance [Member] Employee Severance [Member] Contract Termination [Member] Contract Termination [Member] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Additional Paid-In Capital [Member] Additional Paid-in Capital [Member] Other Ownership Interests by Name [Axis] Other Ownership Interests Name [Axis] Other Ownership Interests, Name [Domain] Other Ownership Interests, Name [Domain] Limited Partner Interest [Member] Limited Partner Interest [Member] Limited Partner Interest [Member] General Partner Interest [Member] General Partner Interest [Member] General Partner Interest [Member] Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] Pioneer Southwest [Member] Pioneer Southwest [Member] Relating to Pioneer Southwest. EFS Midstream [Member] Efs Midstream [Member] EFS Midstream [Member] Wolfcamp [Member] Wolfcamp [Member] Wolfcamp [Member] Sendero [Member] Sendero [Member] Sendero [Member] Summary Of Significant Accounting Policies [Line Items] Summary Of Significant Accounting Policies [Line Items] Summary Of Significant Accounting Policies [Line Items] Accounts receivable - trade Allowances for doubtful accounts Allowance for Doubtful Accounts, Premiums and Other Receivables Natural gas processing plants number Natural Gas Processing Plants Number Natural Gas Processing Plants Number Treating facilities number Treating Facilities Number Treating facilities number Company operated natural gas processing plants Natural Gas Processing Plants Operated Number Natural gas processing plants operated number. Company Operated Treating Facilities Treating Facilities Operated Number Treating facilities operated number. Third party operated natural gas processing plants Third party operated natural gas processing plants Third party operated natural gas processing plants Nonoperated treating facilities Nonoperated treating facilities Nonoperated treating facilities Third party revenues, processing plants and treating facilities Gas Gathering, Transportation, Marketing and Processing Revenue Third party expenses, processing plants and treating facilities Gas Gathering, Transportation, Marketing and Processing Costs Percentage of interest sold Minority Interest Ownership, Percentage Sold Minority Interest Ownership, Percentage Sold Equity Method Investment, Ownership Percentage Equity Method Investment, Ownership Percentage Stock Issued During Period, Shares, New Issues Stock Issued During Period, Shares, New Issues Proceeds from Issuance of Common Stock Proceeds from Issuance of Common Stock Partnerships interest Noncontrolling Interest, Ownership Percentage by Parent Share Per Unit Exchange Ratio Share Per Unit Exchange Ratio Shares of stock to be exchanged for each unit Net income attributable to noncontrolling interests Net Income (Loss) Attributable to Noncontrolling Interest Pioneer Southwest merger transaction costs Adjustments to Additional Paid in Capital, Other Net transfers from noncontrolling interest Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Changes, Net Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests Deferred tax benefit associated with the Pioneer Southwest merger Adjustments to Additional Paid in Capital, Income Tax Benefit from Merger Adjustments to Additional Paid in Capital, Income Tax Benefit from Merger Restructuring and Related Cost, Incurred Cost Restructuring and Related Cost, Incurred Cost Restructuring Reserve Restructuring Reserve Deferred Tax Liabilities, Net, Noncurrent Unamortized Debt Issuance Expense Unamortized Debt Issuance Expense Restructuring and Related Cost, Expected Cost Restructuring and Related Cost, Cost Incurred to Date Property, Plant and Equipment, Gross Property, Plant and Equipment, Gross Goodwill, Written off Related to Sale of Business Unit Goodwill, Written off Related to Sale of Business Unit Joint Venture Investment Ownership Percentage Joint Venture Investment Ownership Percentage Investment in Joint Venture Fair Value Disclosures [Abstract] Assets And Liabilities That Are Measured At Fair Value On A Recurring Basis Fair Value, Assets Measured on Recurring Basis [Table Text Block] Fair Value Measurements, Nonrecurring [Table Text Block] Fair Value Measurements, Nonrecurring [Table Text Block] Fair Value of Assets Classified as Held for Sale [Table Text Block] Fair Value of Assets Classified as Held for Sale [Table Text Block] Fair Value of Assets Classified as Held for Sale [Table Text Block] Fair Value Measurements Not Carried At Fair Value Fair Value, by Balance Sheet Grouping [Table Text Block] Acquisitions and Divestitures [Abstract] Acquisitions and Divestitures [Abstract] Schedule of Disposal Groups, Including Discontinued Operations, Income Statement, Balance Sheet and Additional Disclosures [Table Text Block] Disposal Groups, Including Discontinued Operations [Table Text Block] Subsequent Events [Abstract] Subsequent Events Subsequent Events [Text Block] Compensation and Retirement Disclosure [Abstract] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Award Type [Axis] Award Type [Axis] Equity Award [Domain] Equity Award [Domain] Restricted Stock Equity Awards [Member] Restricted Stock Equity Awards [Member] Restricted Stock-Equity Awards [Member] Restricted Stock Liability Awards [Member] Restricted Stock Liability Awards [Member] Restricted Stock Liability Awards [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Number of Shares/Units, Outstanding at beginning of year Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Number of Shares granted Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Forfeitures, number of shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Awards vested Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Number of Shares/Units, Outstanding at end of year Weighted Average Grant-Date Fair Value, Outstanding at beginning of year Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Weighted Average Grant-Date Fair Value, Shares granted Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Weighted Average Grant-Date Fair Value, Shares vested Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Weighted Average Grant-Date Fair Value, Outstanding at end of year Principles Of Consolidation Consolidation, Policy [Policy Text Block] Reclassification, Policy [Policy Text Block] Reclassification, Policy [Policy Text Block] Use Of Estimates In The Preparation Of Financial Statements Use of Estimates, Policy [Policy Text Block] Cash Equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Accounts Receivable Trade and Other Accounts Receivable, Policy [Policy Text Block] Inventories Inventory, Policy [Policy Text Block] Oil And Gas Properties Oil and Gas Properties Policy [Policy Text Block] Goodwill Goodwill and Intangible Assets Disclosure [Text Block] Other Property And Equipment, Net Property, Plant and Equipment, Policy [Policy Text Block] Investment In Unconsolidated Affiliate Investment In Unconsolidated Affiliate [Policy Text Block] Investment In Unconsolidated Affiliate [Policy Text Block] Asset Retirement Obligations Asset Retirement Obligations, Policy [Policy Text Block] Treasury Stock Treasury Stock [Policy Text Block] Treasury stock policy text block Noncontrolling Interest In Consolidated Subsidiaries Noncontrolling Interest Disclosure [Text Block] Revenue Recognition Revenue Recognition, Policy [Policy Text Block] Derivatives And Hedging Derivatives, Policy [Policy Text Block] Environmental Environmental Costs, Policy [Policy Text Block] Stock-Based Compensation Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block] Segment Reporting Segment Reporting, Policy [Policy Text Block] Assets Held for Sale and Discontinued Operations Discontinued Operations, Policy [Policy Text Block] New Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Statement of Cash Flows [Abstract] Cash flows from operating activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Net income (loss) Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Adjustments to reconcile net income (loss) to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depletion, depreciation and amortization Depreciation, Depletion and Amortization Impairment of oil and gas properties Impairment of Oil and Gas Properties Impairment of inventory and other property and equipment Impairment of Inventory and Other Property and Equipment Impairment of Inventory and Other Property and Equipment Exploration expenses, including dry holes Dry Hole Expense The amount of noncash dry hole and unproved property abandonment expense during the period. Deferred income taxes Deferred Income Tax Expense (Benefit) Gain on disposition of assets, net Gain (Loss) on Disposition of Property Plant Equipment Accretion of discount on asset retirement obligations Asset Retirement Obligation, Accretion Expense Discontinued operations Adjustment Income Loss From Discontinued Operations Net Of Tax Aggregate non-cash (income) loss and investing and financing cash flows from a disposal group. Interest expense Amortization of Financing Costs and Discounts Derivative related activity Noncash Gain Loss On Derivative Instruments Aggregate net noncash gain (loss) on commodity and interest rate derivative instruments. Amortization of stock-based compensation Amortization Stock Based Compensation Non-cash amortization of unvested stock-based compensation during the operating period. Amortization of deferred revenue Deferred Revenue Amortization Deferred revenue recognized but not to be included in current operations cash flows. Other Other Operating Activities, Cash Flow Statement Change in operating assets and liabilities Increase (Decrease) in Operating Capital [Abstract] Accounts receivable, net Increase (Decrease) in Accounts Receivable Income taxes receivable Increase (Decrease) in Income Taxes Receivable Inventories Increase (Decrease) in Inventories Prepaid expenses Increase (Decrease) in Prepaid Expense Other current assets Increase (Decrease) in Other Current Assets Accounts payable Increase (Decrease) in Accounts Payable Interest payable Increase (Decrease) in Interest Payable, Net Income taxes payable Increase (Decrease) in Income Taxes Payable Other current liabilities Increase (Decrease) in Other Current Liabilities Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Cash flows from investing activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Proceeds from disposition of assets, net of cash sold Proceeds from Sale of Productive Assets Payments for acquisitions, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Distribution from (investment in) unconsolidated subsidiary Payments to Acquire Interest in Subsidiaries and Affiliates Additions to oil and gas properties Payments to Acquire Oil and Gas Property Additions to other assets and other property and equipment, net Payments to Acquire Other Productive Assets Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Cash flows from financing activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Borrowings under long-term debt Proceeds from Issuance of Long-term Debt Principal payments on long-term debt Repayments of Long-term Debt Contributions from noncontrolling interests Proceeds from Contributions from Affiliates Distributions to noncontrolling interests Payments of Distributions to Affiliates Payments of other liabilities Borrowings Payments of Other Liabilities Borrowings and payments of other liabilities Exercise of long-term incentive plan stock options and employee stock purchases Proceeds from Stock Options Exercised Purchase of treasury stock Payments for Repurchase of Common Stock Excess tax benefits from share-based payment arrangements Excess Tax Benefit from Share-based Compensation, Financing Activities Payment of financing fees Payments of Financing Costs Dividends paid Payments of Dividends Net cash provided by financing activities Net Cash Provided by (Used in) Financing Activities Net increase (decrease) in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and cash equivalents, beginning of period Cash and cash equivalents, end of period Commitments and Contingencies Disclosure [Abstract] Commitments And Contingencies [Table] Commitments And Contingencies [Table] Commitments And Contingencies [Table] Leasing Activity [Axis] Leasing Activity [Axis] Information by type of leasing activity Leasing Activity [Domain] Leasing Activity [Domain] [Domain] for Information by type of leasing activity Colorado [Member] Colorado [Member] Colorado [Member] Nature of Expense [Axis] Nature of Expense [Axis] Nature of Expense [Domain] Nature of Expense [Domain] nature of expense [Domain] Lease Payments Discontinued Operations [Member] Lease Payments Discontinued Operations [Member] Lease Payments Discontinued operations [Member] Commitments And Contingencies [Line Items] Commitments And Contingencies [Line Items] Commitments And Contingencies [Line Items] Operating Leases, Rent Expense Operating Leases, Rent Expense Operating Leases, Future Minimum Payments Due Operating Leases, Future Minimum Payments Due Year 1 Minimum Lease Commitments Operating Leases, Future Minimum Payments Due, Next Twelve Months Year 2 Minimum Lease Commitments Operating Leases, Future Minimum Payments, Due in Two Years Year 3 Minimum Lease Commitments Operating Leases, Future Minimum Payments, Due in Three Years Year 4 Minimum Lease Commitments Operating Leases, Future Minimum Payments, Due in Four Years Year 5 Minimum Lease Commitments Operating Leases, Future Minimum Payments, Due in Five Years Thereafter Operating Leases, Future Minimum Payments, Due Thereafter Related Party Transactions [Abstract] Related Party Transactions Related Party Transactions Disclosure [Text Block] Employee Stock [Member] Employee Stock [Member] Approved and authorized shares Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Shares issued Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative [Table] Derivative [Table] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event [Member] Subsequent Event [Member] Asset Area [Axis] Asset Area [Axis] Asset Area [Axis] Asset Area [Domain] Asset Area [Domain] [Domain] for Asset Area [Axis] Gulf Coast [Member] Gulf Coast [Member] Gulf Coast [Member] Mid-Continent [Member] Mid-Continent [Member] Mid-Continent [Member] Permian Basin [Member] Permian Basin [Member] Permian Basin [Member] Derivative Instrument Risk [Axis] Derivative Instrument [Axis] Derivative Contract Type [Domain] Derivative Contract [Domain] Gas contracts, in MMBTU [Member] Gas contracts, in MMBTU [Member] Gas contracts, in MMBTU [Member] Gas contracts, price per MMBTU [Member] Gas contracts, price per MMBTU [Member] Gas contracts, price per MMBTU [Member] Trading Activity, by Type [Axis] Trading Activity [Axis] Trading Activity, by Type [Domain] Trading Activity, by Type [Domain] Swap Contracts For First Quarter of Year One [Member] Swap Contracts For First Quarter of Year One [Member] Swap Contracts For First Quarter of Year One [Member] Swap Contracts For Second Quarter of Year One [Member] Swap Contracts For Second Quarter of Year One [Member] Swap Contracts For Second Quarter of Year One [Member] Swap Contracts For Third Quarter of Year One [Member] Swap Contracts For Third Quarter of Year One [Member] Swap Contracts For Third Quarter of Year One [Member] Swap Contracts For Fourth Quarter of Year One [Member] Swap Contracts For Fourth Quarter of Year One [Member] Swap Contracts For Fourth Quarter of Year One [Member] Swap Contracts for Year 2 [Member] Swap Contracts for Year 2 [Member] Swap Contracts for Year 2 [Member] Collar Contracts With Short Puts For First Quarter of Year One [Member] Collar Contracts With Short Puts For First Quarter of Year One [Member] Collar Contracts With Short Puts For First Quarter of Year One [Member] Collar Contracts With Short Puts For Second Quarter of Year One [Member] Collar Contracts With Short Puts For Second Quarter of Year One [Member] Collar Contracts With Short Puts For Second Quarter of Year One [Member] Collar Contracts With Short Puts For Third Quarter of Year One [Member] Collar Contracts With Short Puts For Third Quarter of Year One [Member] Collar Contracts With Short Puts For Third Quarter of Year One [Member] Collar Contracts With Short Puts For Fourth Quarter of Year One [Member] Collar Contracts With Short Puts For Fourth Quarter of Year One [Member] Collar Contracts With Short Puts For Fourth Quarter of Year One [Member] Collar Contracts With Short Puts for Year 2 [Member] Collar Contracts With Short Puts for Year 2 [Member] Collar Contracts With Short Puts for Year 2 [Member] Basis Swap Contracts for First Quarter of Year One [Member] Basis Swap Contracts for First Quarter of Year One [Member] Basis Swap Contracts for First Quarter of Year One [Member] Basis Swap Contracts for Second Quarter of Year One [Member] Basis Swap Contracts for Second Quarter of Year One [Member] Basis Swap Contracts for Second Quarter of Year One [Member] Basis Swap Contracts for Third Quarter of Year One [Member] Basis Swap Contracts for Third Quarter of Year One [Member] Basis Swap Contracts for Third Quarter of Year One [Member] Basis Swap Contracts for Fourth Quarter of Year One [Member] Basis Swap Contracts for Fourth Quarter of Year One [Member] Basis Swap Contracts for Fourth Quarter of Year One [Member] Basis Swap Contracts for Year 2 [Member] Basis Swap Contracts for Year 2 [Member] Basis Swap Contracts for Year 2 Basis Swap Contracts for November 2016 to March 2017 [Member] Basis Swap Contracts for November 2016 to March 2017 [Member] Basis Swap Contracts for November 2016 to March 2017 [Member] Basis Swap Contracts for December of Year One [Member] Basis Swap Contracts for December 2016 [Member] Basis Swap Contracts for December 2016 [Member] Swap Contracts for Next Twelve Months [Member] Swap Contracts for Current Year [Member] Swap Contracts for Current Year [Member] Swap Contracts for Year 3 [Member] Swap Contracts for Year 3 [Member] Swap Contracts for Year 3 [Member] Collar Contracts for Next Twelve Months [Member] Collar Contracts for Next Twelve Months [Member] Collar Contracts for Next Twelve Months [Member] Collar Contracts for Year 2 [Member] Collar Contracts for Year 2 [Member] Collar Contracts for Year 2 [Member] Collar Contracts for Year 3 [Member] Collar Contracts for Year 3 [Member] Collar Contracts for Year 3 [Member] Collar Contracts With Short Puts for Next Twelve Months [Member] Collar Contracts With Short Puts for Current Year [Member] Collar Contracts With Short Puts for Current Year [Member] Collar Contracts With Short Puts for Year 3 [Member] Collar Contracts With Short Puts for Year 3 [Member] Collar Contracts With Short Puts for Year 3 [Member] Basis Swap Contracts for Next Twelve Months [Member] Basis Swap Contracts for Current Year [Member] Basis Swap Contracts for Current Year Basis Swap Contracts for Year 3 [Member] Basis Swap Contracts for Year 3 [Member] Basis Swap Contracts for Year 3 [Member] Derivative, by Nature [Axis] Derivative, by Nature [Axis] Derivative, Name [Domain] Derivative, Name [Domain] Short Put [Member] Short Put [Member] Short Put [Member] Derivative [Line Items] Derivative [Line Items] Derivative, Nonmonetary Notional Amount Derivative, Nonmonetary Notional Amount Derivative, Swap Type, Average Fixed Price Derivative, Swap Type, Average Fixed Price Derivative, Average Cap Price Derivative, Average Cap Price Derivative, Average Floor Price Derivative, Average Floor Price Derivative, Notional Amount, Price Per Unit Derivative, Notional Amount, Price Per Unit The price per unit of the notional amount of the derivative contract expressed in nonmonetary units. For example, the price per barrel specified in a fuel oil forward purchase contract. Commitments And Contingencies Commitments and Contingencies Disclosure [Text Block] Summary Of Open Tax Years, By Jurisdiction Summary of Income Tax Contingencies [Table Text Block] Schedule Of Income Tax (Provision) Benefit Allocation Schedule of Income Tax Expense (Benefit) Intraperiod Allocation [Table Text Block] A schedule of the company's income tax expense (benefit), and its allocation among continuing operations, discontinued operations, extraordinary items, other comprehensive income, and items charged or credited directly to shareholders' equity. Income Tax (Provision) Benefit Attributable To Income From Continuing Operations Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Schedule Of Effective Income Tax Rate Reconciliation Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Schedule Of Deferred Tax Assets And Deferred Tax Liabilities Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Business Combinations [Abstract] Acquisition and Divestitures [Text Block] Mergers, Acquisitions and Dispositions Disclosures [Text Block] Other Expense, Nonoperating [Abstract] Schedule Of Components Of Other Expense Schedule of Other Nonoperating Expense, by Component [Table Text Block] Discontinued Operations Assets and Liabilities Included in Assets and Liabilities Held for Sale [Table] Discontinued Operations Assets and Liabilities Included in Assets and Liabilities Held for Sale [Table] Discontinued Operations Assets and Liabilities Included in Assets and Liabilities Held for Sale [Table] Proceeds To Be Received In Future Year [Member] [Member] Proceeds To Be Received In Future Year [Member] [Member] Proceeds To Be Received In Future Year [Member] Proceeds Received Current Year [Member] Proceeds Received Current Year [Member] Proceeds Received Current Year [Member] Operating Activities [Axis] Operating Activities [Axis] Operating Activities [Domain] Operating Activities [Domain] Lease Contract for Next 12 Months [Member] Lease Contract for Next 12 Months [Member] Lease Contract for Next 12 Months [Member] Lease Contract for Year 2 [Member] Lease Contract through Year 2 [Member] Lease Contract through Year 2 [Member] Discontinued Operations [Member] Discontinued Operations [Member] Disposal Group Name [Axis] Disposal Group Name [Axis] Disposal Groups, Including Discontinued Operations, Name [Domain] Disposal Group Name [Domain] Gaines Dawson [Member] Gaines Dawson [Member] Gaines Dawson [Member] West Panhandle [Member] West Panhandle [Member] West Panhandle [Member] Eagle Ford Shale [Member] Eagle Ford Shale [Member] Eagle Ford Shale [Member] Other Assets [Member] Other Assets [Member] Hugoton field [Member] Hugoton field [Member] Hugoton field [Member] Pioneer Alaska [Member] Pioneer Alaska [Member] Pioneer Alaska [Member] Barnett Shale Field [Member] Barnett Shale Field [Member] Barnett Shale Field [Member] Discontinued Operations Assets and Liabilities Included in Assets and Liabilities Held for Sale [Line Items] Discontinued Operations Assets and Liabilities Included in Assets and Liabilities Held for Sale [Line Items] [Line Items] for Discontinued Operations Assets and Liabilities Included in Assets and Liabilities Held for Sale [Table] Partners' Capital Account, Acquisitions Number of Businesses Acquired Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net Issuance of treasury stock to acquire outstanding PSE units, shares Stock Issued During Period, Shares, Treasury Stock Reissued Gain on disposition of assets, net Equity Method Investment, Net Sales Proceeds Equity Method Investment, Net Sales Proceeds Equity Method Investment, Realized Gain (Loss) on Disposal Equity Method Investment, Realized Gain (Loss) on Disposal Proceeds from Divestiture of Interest in Consolidated Subsidiaries Proceeds from Divestiture of Interest in Consolidated Subsidiaries Drilling rigs leased Drilling rigs leased Drilling rigs leased Idle Rig Expense Idle Rig Expense Expenses from idle and terminate rigs. Significant Acquisitions and Disposals, Acquisition Costs or Sale Proceeds Disposal Group, Including Discontinued Operation, Consideration Maximum Payments From Related Party For Exploration Drilling And Completion Costs Maximum Payments From Related Party For Exploration Drilling And Completion Costs Maximum Payments From Related Party For Exploration Drilling And Completion Costs Payments From Related Party For Exploration Drilling And Completion Costs Percent Payments From Related Party For Exploration Drilling And Completion Costs Percent Payments From Related Party For Exploration Drilling And Completion Costs Percent Energy [Axis] Energy [Axis] Energy [Domain] Energy [Domain] Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Domain] Variable Rate [Domain] Position [Axis] Position [Axis] Position [Domain] Position [Domain] Oil Derivative Contracts Volume And Weighted Average Price Schedule of Oil Derivative Contracts volume and weighted average price [text block] Schedule of Oil Derivative Contracts Volume and Weighted Average Price [Text Block] Schedule of NGL Derivative Volumes and Weighted Average Prices [Table Text Block] Schedule of NGL Derivative Volumes and Weighted Average Prices [Table Text Block] Schedule of NGL Derivative Volumes and Weighted Average Prices [Table Text Block] Gas Volume And Weighted Average Price Schedule of Gas Volume and Weighted Average Price [Text Block] Schedule of Gas Volume and Weighted Average Price [Text Block] Offsetting Asset and Liability [Table Text Block] Offsetting Asset and Liability [Table Text Block] Offsetting Asset and Liability [Table Text Block] Schedule of Derivative Gains and Losses Recognized on Statement of Operations [Table Text Block] Schedule of Derivative Gains and Losses Recognized on Statement of Operations [Table Text Block] Schedule of Derivative Gains and Losses Recognized on Statement of Operations [Text Block] Schedule of Derivative Assets and Liabilities by Counterparty [Table Text Block] Schedule of Derivative Assets and Liabilities by Counterparty [Table Text Block] Schedule of Derivative Assets and Liabilities by Counterparty [Table Text Block] Earnings Per Share [Abstract] Reconciliation Of Earnings Attributable To Common Stockholders, Basic And Diluted Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Reconciliation Of Basic To Diluted Weighted Average Common Shares Outstanding Schedule of Weighted Average Number of Shares [Table Text Block] Schedule of Derivative Assets and Liabilities by Counterparty [Table] Schedule of Derivative Assets and Liabilities by Counterparty [Table] Schedule of Derivative Assets and Liabilities by Counterparty [Table] Merrill Lynch [Member] Merrill Lynch [Member] Merrill Lynch [Member] Citibank, N.A. [Member] Citibank N A [Member] Citibank, N.A. [Member] BMO Financial Group [Member] BMO Financial Group [Member] BMO Financial Group [Member] Societe Generale [Member] Societe Generale [Member] Societe Generale [Member] J. Aron & Company [Member] J. Aron & Company [Member] J. Aron & Company [Member] Morgan Stanley [Member] Morgan Stanley [Member] Morgan Stanley [Member] Wells Fargo Bank, N.A. [Member] Wells Fargo Bank N A [Member] Wells Fargo Bank, N.A. [Member] JP Morgan Chase [Member] Jp Morgan Chase [Member] JP Morgan Chase [Member] Macquarie Bank [Member] Macquarie Bank [Member] Macquarie Bank [Member] Den Norske [Member] Den Norske Bank [Member] Den Norske Bank [Member] Nextera [Member] Nextera [Member] Nextera [Member] Toronto Dominion [Member] Toronto Dominion [Member] Toronto Dominion [Member] Barclays Capital [Member] Barclays Capital [Member] Barclays Capital [Member] Credit Suisse [Member] Credit Suisse [Member] Credit Suisse [Member] Royal Bank of Canada [Member] Royal Bank of Canada [Member] Royal Bank of Canada [Member] Deutsche Bank [Member] Deutsche Bank [Member] Deutsche Bank [Member] BP Corporation North America [Member] BP Corporation North America [Member] BP Corporation North America [Member] BNP Paribas [Member] BNP Paribas [Member] BNP Paribas [Member] Schedule of Derivative Assets and Liabilities by Counterparty [Line Items] Schedule of Derivative Assets and Liabilities by Counterparty [Line Items] Schedule of Derivative Assets and Liabilities by Counterparty [Line Items] Derivative Assets (Liabilities), at Fair Value, Net Derivative Assets (Liabilities), at Fair Value, Net Interest Rate Derivatives [Member] Interest Rate Contract [Member] Commodity Price Derivatives [Member] Commodity Contract [Member] Derivative Instruments, Gain (Loss) by Income Statement Location [Axis] Income Statement Location [Axis] Income Statement and Other Comprehensive Income Location [Domain] Income Statement Location [Domain] Derivative Gains (Losses), Net [Member] Derivative Gains Losses [Member] Derivative gains (losses) [Member] Derivative gains, net Gain (Loss) on Derivative Instruments, Net, Pretax Amount of Gain (Loss) Recognized in Earnings on Derivatives Loss on Derivative Instruments, Pretax Discontinued Operations Balance Sheet Held For Sale [Abstract] Discontinued Operations Balance Sheet Held For Sale [Abstract] Assets of Disposal Group, Including Discontinued Operation, Current Disposal Group, Including Discontinued Operation, Assets, Current Disposal Group, Including Discontinued Operation, Property, Plant, and Equipment, Net Disposal Group, Including Discontinued Operation, Property, Plant and Equipment Disposal Group, Including Discontinued Operation, Deferred Tax Assets Disposal Group, Including Discontinued Operation, Deferred Tax Assets Disposal Group, Including Discontinued Operation, Other Assets Disposal Group, Including Discontinued Operation, Other Assets Liabilities of Disposal Group, Including Discontinued Operation, Current Disposal Group, Including Discontinued Operation, Liabilities, Current Disposal Group, Including Discontinued Operation, Other Liabilities Disposal Group, Including Discontinued Operation, Other Liabilities Debt Disclosure [Abstract] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Total Debt To Book Capitalization [Member] Total Debt To Total Capitalization [Member] Total Debt To Total Capitalization [Member] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Swing Line Loans [Member] Swing Line Loans [Member] Swing Line Loans [Member] 2.875% Convertible Senior Notes Due 2038 [Member] Two Point Eight Seven Five Percent Senior Convertible Notes Due Two Thousand Thirty Eight [Member] Two Point Eight Seven Five Percent Senior Convertible Notes Due Two Thousand Thirty Eight [Member] 3.45% Senior Notes Due 2021 [Member] 3.45% Senior Notes Due 2021 [Member] Three Point Four Five Percentage Senior Notes Due Two Thousand And Twenty One [Member] 4.45% Senior Notes Due 2022 [Member] 4.45% Senior Notes Due 2022 [Member] 4.45% Senior Notes Due 2022 [Member] Combined 3.45% and 4.45% Senior Notes [Member] Combined 3.45% and 4.45% Senior Notes [Member] Combined 3.45% and 4.45% Senior Notes [Member] Pioneer Credit Facility [Member] Pioneer Credit Facility [Member] Pioneer Credit Facility [Member] Line of credit facility, maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Outstanding borrowings under the Credit Facility Long-term Line of Credit Maximum outstanding borrowings under the Credit Facility Line of Credit Facility, Maximum Amount Outstanding During Period Federal fund rate Rate of Interest on Base Rate Committed Loans In Addition To Federal Fund Rate Rate of Interest on Base Rate Committed Loans In Addition To Federal Fund Rate Alternate base rate spread ABR Margin ABR Margin Applicable margin Applicable Margin Applicable Margin Letters of credit outstanding under the Credit Facility, interest percentage Letter of Credit Interest Percentage Letter of Credit Interest Percentage Unused portion, fee percentage Line of Credit Facility, Unused Capacity, Commitment Fee Percentage Debt instrument covenant description Debt Instrument, Covenant Description Issuance of senior notes Senior Notes Senior Notes, interest rate, percentage Debt Instrument, Interest Rate, Stated Percentage Convertible debt Convertible Debt Principal amount of notes tendered for conversion Debt Conversion, Original Debt, Amount Cash Paid To Conversion Of Convertible Senior Notes Cash Paid To Conversion Of Convertible Senior Notes Cash Paid To Conversion Of Convertible Senior Notes Shares received for conversion of debt Debt Conversion, Converted Instrument, Shares Issued Cash Paid To Redeem Convertible Debt Cash Paid To Redeem Convertible Debt Cash Paid To Redeem Convertible Debt Interest expense relating to the contractual interest coupon and unamortized discount Interest Expense, Debt Debt instrument, effective interest rate, percentage Debt Instrument, Interest Rate, Effective Percentage Debt instrument, Unamortized Discount and Fee Amounts Debt instrument, Unamortized Discount and Fee Amounts Debt instrument, Unamortized Discount and Fee Amounts Senior notes offering discounts and cost Debt Instrument, Unamortized Discount Line of Credit Facility, Agreement Term, Duration Line of Credit Facility, Agreement Term, Duration Line of Credit Facility, Agreement Term, Duration Undrawn letters of credit Undrawn Letters Of Credit Undrawn Letters Of Credit Unused borrowing capacity Line of Credit Facility, Remaining Borrowing Capacity Credit facility, description Line of Credit Facility, Description Income Tax Contingency [Table] Income Tax Contingency [Table] Income Tax Authority [Axis] Income Tax Authority [Axis] Income Tax Authority [Domain] Income Tax Authority [Domain] UNITED STATES UNITED STATES Various U.S. States [Member] Various States In U S [Member] Relating to various states in the United States. Foreign Country [Member] Foreign Tax Authority [Member] South Africa [Member] South Africa [Member] South Africa [Member] Income Tax Contingency [Line Items] Income Tax Contingency [Line Items] Open tax years, by jurisdiction Open Tax Year Interest and Other Income [Abstract] Equity interest in income (loss) of EFS Midstream Income (Loss) from Equity Method Investments Deferred compensation plan income Deferred Compensation Plan Income Deferred Compensation Plan Income Interest income Other Interest and Dividend Income Other income Other Income Total interest and other income Other Nonoperating Income Concentration Risks, Types, No Concentration Percentage [Abstract] Major Customers Concentration Risk Disclosure [Text Block] Fair Value Disclosures - Nonrecurring [Abstract] Fair Value Disclosures - Nonrecurring [Abstract] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Impaired Long-Lived Assets Held and Used by Type [Axis] Impaired Long-Lived Assets Held and Used by Type [Axis] Impaired Long-Lived Assets Held and Used, Asset Name [Domain] Impaired Long-Lived Assets Held and Used, Asset Name [Domain] South Texas Eagle Ford Shale [Member] South Texas Eagle Ford Shale [Member] South Texas Eagle Ford Shale [Member] South Texas Edwards And Austin Chalk [Member] South Texas Edwards And Austin Chalk [Member] SouthTexasEdwardsAndAustinChalkMember Raton Field [Member] Raton Field [Member] Raton Field [Member] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value of Asset Group Fair Value of Asset Group Fair Value of Asset Group Impairment of oil and gas properties Management oil price outlook Management oil price outlook Management oil price outlook Management gas price outlook Management gas price outlook Management gas price outlook Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest Net Income Attributable to Noncontrolling Interest Income (loss) from continuing operations before tax Income loss from continuing operations before tax Income loss from continuing operations before tax U.S. federal statutory tax rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Income Tax Reconciliation, Income Tax (Expense) Benefit, at Federal Statutory Income Tax Rate Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount Income Tax Reconciliation, State and Local Income Taxes Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount Unrecognized tax benefit recognized in period Unrecognized tax benefit recognized in period Unrecognized tax benefit recognized in period Income Tax Reconciliation, Other Adjustments Effective Income Tax Rate Reconciliation, Other Adjustments, Amount Income Tax (Expense) Benefit Income Tax Expense (Benefit) Effective Income Tax Rate, Continuing Operations Effective Income Tax Rate Reconciliation, Percent Income Statement [Abstract] Revenues and other income: Revenues [Abstract] Oil and Gas Revenue Oil and Gas Revenue Sales of purchased oil and gas Revenue from Purchased Oil and Gas Interest and other Revenues Revenues Costs and expenses: Costs and Expenses [Abstract] Oil and Gas Production Expense Oil and Gas Production Expense Production and ad valorem taxes Taxes, Miscellaneous Purchased oil and gas Cost of Purchased Oil and Gas Exploration and abandonments Exploration Abandonment and Impairment Expense General and administrative General and Administrative Expense Interest Interest Expense Other Other Nonoperating Expense Costs and expenses, Total Costs and Expenses Income (loss) from continuing operations before income taxes Income tax benefit (provision) Income (loss) from continuing operations Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest Loss from discontinued operations, net of tax Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest Net income (loss) Net income (loss) attributable to common stockholders Net Income (Loss) Attributable to Parent Basic earnings per share: Earnings Per Share, Basic [Abstract] Income (loss) from continuing operations attributable to common stockholders Income (Loss) from Continuing Operations, Per Basic Share Loss from discontinued operations attributable to common stockholders Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Basic Share Net income (loss) attributable to common stockholders Earnings Per Share, Basic Diluted earnings per share: Earnings Per Share, Diluted [Abstract] Income (loss) from continuing operations attributable to common stockholders Income (Loss) from Continuing Operations, Per Diluted Share Loss from discontinued operations attributable to common stockholders Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Diluted Share Net income (loss) attributable to common stockholders Earnings Per Share, Diluted Weighted average shares outstanding: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Basic Weighted Average Number of Shares Outstanding, Basic Diluted Weighted Average Number of Shares Outstanding, Diluted Amounts attributable to common stockholders: Income Amounts Attributable to Parent, Disclosures [Abstract] Income (loss) from continuing operations, net of tax Income (Loss) from Continuing Operations Attributable to Parent Income (loss) from discontinued operations, net of tax Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent Net income (loss) Reconciliation of Basic Weighted Average Shares to Diluted Weighted Average Shares [Table] Reconciliation of Basic Weighted Average Shares to Diluted Weighted Average Shares [Table] Reconciliation of Basic Weighted Average Shares to Diluted Weighted Average Shares [Table] Antidilutive Securities Excluded from Computation of Earnings Per Share, by Antidilutive Securities [Axis] Antidilutive Securities [Axis] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Stock Options [Member] Employee Stock Option [Member] Performance Unit Awards [Member] Performance Shares [Member] Unvested Performance units [Member] Unvested Performance units [Member] Unvested Performance units [Member] Conversion rights [Member] Conversion rights [Member] Conversion rights [Member] Weighted Average Number of Shares Outstanding Reconciliation [Line Items] Weighted Average Number of Shares Outstanding Reconciliation [Line Items] Weighted Average Number of Shares Outstanding Reconciliation [Line Items] Dilutive common stock options Incremental Common Shares Attributable to Dilutive Effect of Call Options and Warrants Contingently issuable - performance shares Incremental Common Shares Attributable to Dilutive Effect of Contingently Issuable Shares Diluted Antidilutive securities excluded from computation of earnings per share, amount Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Summary Of Significant Accounting Policies Basis of Presentation and Significant Accounting Policies [Text Block] Common stock, par value Common Stock, Par or Stated Value Per Share Common stock, shares authorized Common Stock, Shares Authorized Common stock, shares issued Common Stock, Shares, Issued Treasury stock, shares Treasury Stock, Shares Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Derivative Current [Member] Derivative Current [Member] Derivative Current [Member] Derivative Noncurrent [Member] Derivative Noncurrent [Member] Derivative Noncurrent [Member] Hedging Designation [Axis] Hedging Designation [Axis] Hedging Designation [Domain] Hedging Designation [Domain] Not Designated As Hedging Instruments [Member] Not Designated as Hedging Instrument [Member] Total derivatives, Asset Derivative Asset, Fair Value, Gross Asset Total derivatives, Liability Derivative Liability, Fair Value, Gross Liability Derivative Assets Offset In Balance Sheet Derivative Assets Offset In Balance Sheet Derivative Assets Offset In Balance Sheet Derivative Liabilities Offset In Balance Sheet Derivative Liabilities Offset In Balance Sheet Derivative Liabilities Offset In Balance Sheet Derivative Asset, Current Derivative Asset, Noncurrent Derivative Asset, Fair Value, Amount Not Offset Against Collateral Derivative Asset, Fair Value, Amount Not Offset Against Collateral Derivative Liability, Current Derivative Liability, Noncurrent Derivative Financial Instruments, Liabilities, Fair Value Disclosure Derivative Liability, Fair Value, Amount Not Offset Against Collateral Components of Discontinued Operations [Abstract] Components of Discontinued Operations [Abstract] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Table] Disposal Groups, Including Discontinued Operations [Table] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Interest and other Gain on disposition of assets, net Total revenues and other income from discontinued operations Total Revenues And Other Income From Discontinued Operations Total revenues and income from equity affiliates and other income from discontinued operations. Production and Ad Valorem Taxes From Discontinued Operations Exploration Abandonment and Impairment Expense Other Income (loss) from discontinued operations before income taxes Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax Current Current Income Tax Expense (Benefit) Deferred Loss from discontinued operations Property, Plant and Equipment [Abstract] Schedule of Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Proved and Unproved Sand Leaseholds [Member] Proved and Unproved Sand Leaseholds [Member] Proved and Unproved Sand Leaseholds [Member] Land and Building [Member] Land and Building [Member] Wells and Related Equipment and Facilities [Member] Wells and Related Equipment and Facilities [Member] Water infrastructure [Member] Water infrastructure [Member] Water infrastructure [Member] Transportation Equipment [Member] Transportation Equipment [Member] Furniture and Fixtures [Member] Furniture and Fixtures [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Accumulated depreciation property, plant and equipment, other assets Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Fracture Stimulation Fleets Fracture Stimulation Fleets Fracture Stimulation Fleets Owned Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] Fair Value, Inputs, Level 1 [Member] Significant Other Observable Inputs (Level 2) [Member] Fair Value, Inputs, Level 2 [Member] Significant Unobservable Inputs (Level 3) [Member] Fair Value, Inputs, Level 3 [Member] Commodity Derivatives [Member] Commodity [Member] Trading Securities, Fair Value Disclosure Trading Securities Deferred Compensation Plan Assets Deferred Compensation Plan Assets Assets, Fair Value Disclosure Assets, Fair Value Disclosure Liabilities, Fair Value Disclosure Financial and Nonfinancial Liabilities, Fair Value Disclosure Recurring Measurements, (Fair Value, Total) Recurring Measurements, (Fair Value, Net) Recurring Measurements, (Fair Value, Net). Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Performance Units [Member] Performance Units [Member] Performance Units [Member] Other Incentive Awards [Member] Other Incentive Awards [Member] Other Incentive Awards [Member] Compensation Expense For Incentive Awards [Member] Compensation Expense For Incentive Awards [Member] Compensation Expense For Incentive Awards [Member] Deferred Compensation Arrangement with Individual, Compensation Expense Deferred Compensation Arrangement with Individual, Compensation Expense Proceeds from Issuance of Shares under Incentive and Share-based Compensation Plans, Including Stock Options Proceeds from Issuance of Shares under Incentive and Share-based Compensation Plans, Including Stock Options Schedule of Inventory, Current [Table Text Block] Schedule of Inventory, Current [Table Text Block] Other Property Plant and Equipment [Table Text Block] Other Property Plant and Equipment [Table Text Block] Other Property Plant and Equipment [Table Text Block] U.S. federal Current Federal Tax Expense (Benefit) U.S. state Current State and Local Tax Expense (Benefit) Foreign Current Foreign Tax Expense (Benefit) Current income tax (provision) benefit U.S. federal Deferred Federal Income Tax Expense (Benefit) U.S. state Deferred State and Local Income Tax Expense (Benefit) Deferred income tax (provision) benefit Income tax (provision) benefit Schedule of Future Minimum Drilling Commitments [Table Text Block] Schedule of Future Minimum Drilling Commitments [Table Text Block] [Table Text Block] for Schedule of Future Minimum Drilling Commitments [Table] Future Minimum Lease Commitments Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Future Minimum Gathering, Processing And Transportation Fees Schedule of Future Minimum Transportation Fees [Table Text Block] Schedule of Future Minimum Transportation Fees [Table Text Block] Net Income Per Share Attributable to Common Stockholders [Abstract] Net Income Per Share Attributable to Common Stockholders [Abstract] Earnings Per Share, Policy [Policy Text Block] Earnings Per Share, Policy [Policy Text Block] Compensation and Employee Benefit Plans [Text Block] Compensation and Employee Benefit Plans [Text Block] Current annual salaries of officers and key employees Officer And Key Employee Compensation Expenditures for salaries of officers and key employees. Asset Retirement Obligation [Abstract] Asset Retirement Obligations Asset Retirement Obligation Disclosure [Text Block] Other Expense [Abstract] Other Expense [Abstract] Other Expense Other Nonoperating Income and Expense [Text Block] Employee Type [Axis] Employee Type [Axis] Employee Type [Axis] Employee Type [Domain] Employee Type [Domain] [Domain] for Employee Type [Axis] Officer [Member] Officer [Member] Key Employee [Member] Key Employee [Member] Key Employee [Member] Other Postretirement Benefits, Individual Contracts, Type of Deferred Compensation [Axis] Other Postretirement Benefits, Individual Contracts, Type of Deferred Compensation [Axis] Other Postretirement Benefits, Individual Contracts, Type of Deferred Compensation [Domain] Other Postretirement Benefits, Individual Contracts, Type of Deferred Compensation [Domain] Deferred Compensation Retirement Plan [Member] Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member] 401(k) Plan [Member] 401(k) Plan [Member] 401(k) Plan [Member] Restricted Stock Units (RSUs) [Member] Restricted Stock Units (RSUs) [Member] Restricted Stock [Member] Restricted Stock [Member] Performance Unit Awards [Member] Performance Unit Awards [Member] Performance Unit Awards [Member] Pioneer Long-Term Incentive Plan [Member] Pioneer Long Term Incentive Plan [Member] Pioneer Long Term Incentive plan [Member] PSE Employee Long Term Incentive Plan [Member] Pioneer Southwest Employee Long Term Incentive Plan [Member] PSE Employee Long Term Incentive Plan [Member] PSE Ltip Phantom Units [Member] PSE Ltip Phantom Units [Member] PSE Ltip Phantom Units [Member] Pioneer Southwest LTIP [Member] Pioneer Southwest Long Term Incentive Plan [Member] Pioneer Southwest Long-Term Incentive Plan [Member] Sendero B Units [Member] Sendero B Units [Member] Sendero B Units [Member] Schedule of Trading Securities and Other Trading Assets, Major Types of Trading Securities and Assets [Axis] Major Types of Debt and Equity Securities [Axis] Major Types of Trading Securities and Assets [Domain] Major Types of Debt and Equity Securities [Domain] Base Salary [Member] Base Salary [Member] Base Salary [Member] Bonus [Member] Bonus [Member] Bonus [Member] Participants annual salary contributions, percentage Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent Matching contributions percent Defined Contribution Plan, Employer Matching Contribution, Percent of Match Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay Matching contributions Deferred Compensation Arrangement with Individual, Employer Contribution Matching contributions vesting period in years Four Zero One K Plan Matching Contributions Vesting Period 401(k) Plan Matching Contributions Vesting Period in years. Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Employee stock purchase plan contribution limit Employee Stock Purchase Plan Contribution Limit Employee Stock Purchase Plan Contribution Limit Employee stock purchase plan participants purchase price percent Employee Stock Purchase Plan Participants Purchase Price Percent Discount available to Employees on the market price of stock available for purchase according to their purchase plan. Unrecognized share-based compensation expense Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Restricted Units Vesting Schedule Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Number of unvested shares Restricted Stock Awards Unvested Shares At Balance Sheet Date The number of unvested restricted stock shares not reflected in balance sheet Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value Amount of liabilities attributable to liability awards included in accounts payable Accounts Payable, Current Option awards contract life Option Awards Contract Life Option Awards Contract Life Average dividend yield Share Based Compensation Arrangement By Share Based Payment Award Options Average Dividend Yield In Period Share Based Compensation Arrangement By Share Based Payment Award Options Average Dividend Yield In Period Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercised, Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Service period for the performance unit awards, years Deferred Compensation Arrangement with Individual, Requisite Service Period Restricted units to directors Long Term Incentive Plan Restricted units to directors Long Term Incentive Plan Restricted units to directors Number of key employees participated in restricted unit agreements Number Of Key Employees Participated In Restricted Unit Agreements Number of key employees participated in restricted unit agreements Unfunded accumulated postretirement benefit obligations determined by actuaries Defined Benefit Plan, Benefit Obligation Grant date fair value Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Approved and authorized awards Grant Date Fair Value Grant Date Fair Value Grant Date Fair Value Components Of Long-Term Debt Schedule of Long-term Debt Instruments [Table Text Block] Principal Maturities Of Long-Term Debt Schedule of Maturities of Long-term Debt [Table Text Block] Interest Expense Schedule Of Interest Expense [Table Text Block] Schedule Of Interest Expense [Table Text Block] Schedule of Earnings Per Share, Basic and Diluted, by Common Class, Including Two Class Method [Table] Schedule of Earnings Per Share, Basic and Diluted, by Common Class, Including Two Class Method [Table] Schedule of Earnings Per Share, Basic and Diluted, by Common Class, Including Two Class Method [Table] Segment, Continuing Operations [Member] Continuing Operations [Member] Statement Operating Activities Segment [Line Items] Statement Operating Activities Segment [Line Items] Statement Operating Activities Segment [Line Items] Participating Securities, Distributed and Undistributed Earnings (Loss), Basic Participating Securities, Distributed and Undistributed Earnings (Loss), Basic Reallocation of participating earnings Dilutive Securities, Effect on Basic Earnings Per Share Net Income (Loss) Available to Common Stockholders, Basic Net Income (Loss) Available to Common Stockholders, Basic Diluted income (loss) attributable to common stockholders Net Income (Loss) Available to Common Stockholders, Diluted Schedule of Financial Assets and Liabilities Not Carried At Fair Value [Abstract] Schedule of Financial Assets and Liabilities Not Carried At Fair Value [Abstract] Fair Value Assets and Liabilities Not Carried At Fair Value [Table] Fair Value Assets and Liabilities Not Carried At Fair Value [Table] Fair Value Assets and Liabilities Not Carried At Fair Value [Table] Fair Value, by Balance Sheet Grouping, Disclosure Item Amounts [Axis] Measurement Basis [Axis] Fair Value, Disclosure Item Amounts [Domain] Fair Value Measurement [Domain] Reported Value Measurement [Member] Reported Value Measurement [Member] Estimate of Fair Value Measurement [Member] Estimate of Fair Value Measurement [Member] Fair Value Assets and Liabilities Not Carried At Fair Value [Line Items] Fair Value Assets and Liabilities Not Carried At Fair Value [Line Items] [Line Items] for Fair Value Assets and Liabilities Not Carried At Fair Value [Table] Long-term Debt Long-term Debt Oil contracts, price per bbl [Member] Oil contracts, price per bbl [Member] Oil contracts, price per bbl [Member] Oil contracts [Member] Oil contracts [Member] Oil contracts [Member] Collar Contracts With Short Puts For March to June of Year One [Member] Collar Contracts With Short Puts For March to June of Year One Converted [Member] Collar Contracts With Short Puts For March to June of Year One Converted [Member] Swap Contracts For March to June of Year One [Member] Swap Contracts For March to June of Year One [Member] Swap Contracts For March to June of Year One [Member] Rollfactor Swap Contracts for Next Twelve Months [Member] Rollfactor Swap Contracts for Current Year [Member] Rollfactor Swap Contracts for Current Year [Member] Rollfactor Swap Contracts for Year 2 [Member] Rollfactor Swap Contracts for Year 2 [Member] Rollfactor Swap Contracts for Year 2 [Member] Rollfactor Swap Contracts [Member] Rollfactor Swap Contracts [Member] Rollfactor Swap Contracts [Member] Rollfactor Swap Contracts for Year 3 [Member] Rollfactor Swap Contracts for Year 3 [Member] Rollfactor Swap Contracts for Year 3 [Member] Trading Activity, Gains and Losses, Net [Line Items] Trading Activity, Gains and Losses, Net [Line Items] Inventory Write-down Inventory Write-down discount rate used in impairment calculation discount rate used in impairment calculation discount rate used in impairment calculation Impairment of Long-Lived Assets Held-for-use Impairment of Long-Lived Assets Held-for-use Capitalized Exploratory Well Costs [Abstract] Exploratory Well Costs Oil and Gas Exploration and Production Industries Disclosures [Text Block] Major Customers And Derivative Counterparties [Abstract] Major Customers And Derivative Counterparties [Abstract] Schedule of Revenue by Major Customer Schedule of Revenue by Major Customers by Reporting Segments [Table Text Block] Schedule of Sales of Purchased Oil and Gas by Major Customer Schedule of Sales of Purchased Oil and Gas by Major Customer [Table Text Block] Schedule of Sales of Purchased Oil and Gas by Major Customer [Table Text Block] Organization, Consolidation and Presentation of Financial Statements [Abstract] Organization And Nature Of Operations Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Valuation Allowance [Table] Valuation Allowance [Table] COLORADO COLORADO KANSAS KANSAS Valuation Allowance by Deferred Tax Asset [Axis] Valuation Allowance by Deferred Tax Asset [Axis] Deferred Tax Asset [Domain] Deferred Tax Asset [Domain] Valuation Allowance [Line Items] Valuation Allowance [Line Items] Net operating loss carryforward Deferred Tax Assets, Operating Loss Carryforwards Asset retirement obligations Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Asset Retirement Obligations Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost Other Deferred Tax Assets, Other Total deferred tax assets Deferred Tax Assets, Gross Net deferred tax assets Deferred Tax Assets, Net of Valuation Allowance Oil and gas properties, principally due to differences in basis, depletion and the deduction of intangible drilling costs for tax purposes Deferred Tax Liabilities, Property, Plant and Equipment Other property and equipment, principally due to the deduction of bonus depreciation for tax purposes Deferred Tax Liabilities, Other Finite-Lived Assets Net deferred hedge gains Deferred Tax Liabilities Hedge Gains Net Deferred Tax Liabilities Hedge Gains Net State taxes and other Deferred Tax Liabilities, Other Total deferred tax liabilities Deferred Tax Liabilities, Gross, Noncurrent Deferred Tax Liabilities, Net Deferred Tax Liabilities, Net Net deferred tax liability Deferred Tax Assets, Net Valuation allowances Deferred Tax Assets, Valuation Allowance Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration Statement of Stockholders' Equity [Abstract] Report Date [Axis] Report Date [Axis] Financial Statements Date [Domain] Financial Statement Filing Date [Domain] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] Adjustments for Revisions [Axis] Adjustments for Error Corrections [Axis] Adjustments for Revisions [Domain] Adjustments for Error Correction [Domain] Dividends declared, per share Common Stock, Dividends, Per Share, Declared Performance Units, including Retirement Deferred Units [Member] Performance Units, including Retirement Deferred Units [Member] Performance Units, including Retirement Deferred Units [Member] Retirement Deferred Performance Units [Member] [Member] Retirement Deferred Performance Units [Member] [Member] Retirement Deferred Performance Units [Member] [Member] Performance Units Service Period Lapsed [Member] Performance Units Service Period Lapsed [Member] Performance Units Service Period Lapsed [Member] Retirement Deferred Performance Units Service Period Lapse [Member] Retirement Deferred Performance Units Service Period Lapse [Member] Retirement Deferred Performance Units Service Period Lapse [Member] Number of Units granted Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period Weighted Average Grant-Date Fair Value, Units granted Weighted Average Grant Date Fair Value, Units vested Performance percentage of actual payout minimum Performance Percentage Of Actual Payout Minimum Performance Percentage Of Actual Payout Minimum Performance percentage to reach maximum Performance percentage to reach maximum Performance percentage to reach Maximum Number of shares earned for each vested award Number Of Shares Earned For Each Vested Award Number Of Shares Earned For Each Vested Award Common Stock [Member] Common Stock [Member] Treasury Stock [Member] Treasury Stock [Member] Retained Earnings [Member] Retained Earnings [Member] Accumulated Other Comprehensive Income (Loss) [Member] AOCI Attributable to Parent [Member] Noncontrolling Interests [Member] Noncontrolling Interest [Member] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Beginning Balance Beginning Balance, shares Shares, Outstanding Issuance of Common Stock Stock Issued During Period, Value, New Issues Sale of Pioneer Southwest common units, net of tax Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Changes, Sale of Interest by Parent Issuance of Pioneer Southwest common units, net of tax Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Changes, Issuance of Equity by Subsidiary to Noncontrolling Interests Dividends declared ($0.08 per share) Dividends, Cash Exercise of long-term incentive plan stock options and employee stock purchases, shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Exercise of long-term incentive plan stock options and employee stock purchases Stock Issued During Period, Value, Stock Options Exercised Purchase of treasury stock, shares Treasury Stock, Shares, Acquired Purchase of treasury stock Treasury Stock, Value, Acquired, Cost Method Conversion of 2.875% senior convertible notes, shares Stock Issued During Period, Shares, Conversion of Convertible Securities Stock Issued During Period, Value, Conversion of Convertible Securities Stock Issued During Period, Value, Conversion of Convertible Securities Noncontrolling Interest, Decrease from Deconsolidation Noncontrolling Interest, Decrease from Deconsolidation Deferred tax benefit related to conversion of 2.875% senior convertible notes Adjustments to Additional Paid in Capital, Income Tax Benefit from Conversion of Convertible Notes Adjustments to Additional Paid in Capital, Income Tax Benefit from Conversion of Convertible Notes Tax benefits related to stock-based compensation Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation Deferred tax provision attributable to 2008 Pioneer Southwest initial public offering Subsidiary or Equity Method Investee, Deferred Income Tax Provision on Gain (Loss) Recognized, Amount Issuance of treasury stock to acquire outstanding PSE units Stock Issued During Period, Value, Treasury Stock Reissued Compensation costs: Share-based Compensation [Abstract] Vested compensation awards, net, shares Stock Issued Or Vested During Period Shares Stock Awards Number of common stock issued as a result of granting or vesting of employee stock awards (including income tax benefits), and the shares of treasury stock purchases related to withholding taxes. Vested compensation awards, net Stock Issued Or Vested During Period Value Stock Awards Par value of share-based payments that vest or lapse during the period. Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Cash contributions from noncontrolling interests Proceeds from Noncontrolling Interests Cash distributions to noncontrolling interests Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders Other comprehensive income (loss): Other Comprehensive Income (Loss), Net of Tax [Abstract] Deferred hedging activity, net of tax: Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax [Abstract] Hedge fair value changes, net Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax Net hedge (gains) losses included in continuing operations Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax Ending Balance Ending Balance, shares Expected option life - years Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Volatility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Risk-free interest rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Dividend yield Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Capitalized Exploratory Well And Project Activity Capitalized Exploratory Well And Project Activity Capitalized Exploratory Well And Project Activity Capitalized Exploratory Costs And The Number Of Projects For Which Exploratory Costs Have Been Capitalized Schedule of Projects with Exploratory Well Costs Capitalized for More than One Year [Table Text Block] Awards available for future grant Subsequent Event [Table] Subsequent Event [Table] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum [Member] Minimum [Member] Maximum [Member] Maximum [Member] Subsequent Event [Line Items] Subsequent Event [Line Items] Restructuring and Related Cost, Expected Cost Restructuring and Related Cost, Expected Cost Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Debt Instrument [Line Items] Debt Instrument [Line Items] 2016 Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months 2017 Long-term Debt, Maturities, Repayments of Principal in Year Two 2018 Long-term Debt, Maturities, Repayments of Principal in Year Three 2019 Long-term Debt, Maturities, Repayments of Principal in Year Four