Acquisition and Divestitures (Business Combinations) [Abstract] Acquisition and Divestitures (Business Combinations) [Abstract] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Permian Basin [Member] Permian Basin [Member] Permian Basin [Member] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Business Acquisition [Line Items] Business Acquisition [Line Items] Gas and Oil Area, Developed, Net Gas and Oil Area, Developed, Net Production, Barrels of Oil Equivalents Production, Barrels of Oil Equivalents Business acquisition Payments to Acquire Businesses, Net of Cash Acquired Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Buildings Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Buildings Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net Business Acquisition, Transaction Costs Business Acquisition, Transaction Costs Commitments and Contingencies Disclosure [Abstract] Other Commitment, Due in Next Twelve Months Other Commitment, Due in Next Twelve Months Other Commitment, Due in Second Year Other Commitment, Due in Second Year Other Commitment, Due in Third Year Other Commitment, Due in Third Year Other Commitment, Due in Fourth Year Other Commitment, Due in Fourth Year Other Commitment, Due in Fifth Year Other Commitment, Due in Fifth Year Other Commitment, Due Thereafter Other Commitment, Due Thereafter Other Commitment, Due Thereafter Income Tax Disclosure [Abstract] Income tax benefit (provision) Income Tax Expense (Benefit) Income tax from discontinued operations Discontinued Operation, Tax Effect of Discontinued Operation Changes in goodwill - tax benefits related to stock-based compensation Income Tax Effect Allocated to Changes in Goodwill due to stock-based compensation The income tax benefit attributable to changes in goodwill - tax benefits related to stock-based compensation. Net deferred hedge loss Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax Tax benefits related to stock-based compensation Income Tax Effects Allocated Directly to Equity, Employee Stock Options Income Tax Effects Allocated Directly to Equity, Equity Transactions Income Tax Effects Allocated Directly to Equity, Equity Transactions 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 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 Schedule of Cash and Cash Equivalents and Investments [Abstract] Schedule of Cash and Cash Equivalents and Investments [Abstract] Schedule of Held-to-maturity Securities [Table] Schedule of Held-to-maturity Securities [Table] Debt Security [Axis] Debt Security [Axis] Major Types of Debt Securities [Domain] Major Types of Debt Securities [Domain] Cash and Cash Equivalents [Member] Cash and Cash Equivalents [Member] Commercial Paper [Member] Commercial Paper [Member] Corporate Bond Securities [Member] Corporate Bond Securities [Member] Bank Time Deposits [Member] Bank Time Deposits [Member] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Schedule of Held-to-maturity Securities [Line Items] Schedule of Held-to-maturity Securities [Line Items] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Short-term Investments Short-term Investments Long-term Investments Long-term Investments Cash, Cash Equivalents, and Short-term Investments Cash, Cash Equivalents, and Short-term Investments 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] Operating Activities [Axis] Operating Activities [Axis] Operating Activities [Domain] Operating Activities [Domain] 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] Pioneer Alaska [Member] Pioneer Alaska [Member] Pioneer Alaska [Member] Barnett Shale Field [Member] Barnett Shale Field [Member] Barnett Shale Field [Member] Hugoton field [Member] Hugoton field [Member] Hugoton field [Member] 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] Oil and Gas Revenue Oil and Gas Revenue 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. Oil and Gas Production Expense Oil and Gas Production Expense Impairment of oil and gas properties Impairment of Oil and Gas Properties Costs and expenses, Total Costs and Expenses 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 Deferred Income Tax Expense (Benefit) Loss from discontinued operations Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest Accounting Policies [Abstract] Schedule of Inventory [Table] Schedule of Inventory [Table] Schedule of Inventory [Table] Inventory [Axis] Inventory [Axis] Inventory [Domain] Inventory [Domain] Inventory [Domain] Schedule of Inventory [Line Items] Schedule of Inventory [Line Items] [Line Items] for Schedule of Inventory [Table] Materials and supplies inventories Inventory, Raw Materials and Supplies, Net of Reserves Commodities Energy Related Inventory, Crude Oil and Natural Gas Liquids Inventory, Drilling, Noncurrent Inventory, Drilling, Noncurrent Inventories Inventory, Net Net materials and supplies inventories reserves Inventory Valuation Reserves 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] Earnings Per Share [Abstract] 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] Basic Weighted Average Number of Shares Outstanding, Basic 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 Weighted Average Number of Shares Outstanding, Diluted Antidilutive securities excluded from computation of earnings per share, amount Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Statement of Stockholders' Equity [Abstract] Statement [Table] Statement [Table] Scenario [Axis] Scenario [Axis] Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Report Date [Axis] Report Date [Axis] Financial Statements Date [Domain] Financial Statement Filing Date [Domain] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] 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 Revisions [Axis] Adjustments for Error Corrections [Axis] Adjustments for Revisions [Domain] Adjustments for Error Correction [Domain] Statement [Line Items] Statement [Line Items] Dividends declared, per share Common Stock, Dividends, Per Share, Declared Capitalized Exploratory Well Costs [Abstract] One year or less Capitalized Exploratory Well Costs that Have Been Capitalized for Period of One Year or Less More than one year Capitalized Exploratory Well Costs that Have Been Capitalized for Period Greater than One Year Capitalized exploratory well costs, total suspended Capitalized Exploratory Well Costs Number of projects with exploratory well costs that have been suspended for a period greater than one year Projects that have Exploratory Well Costs that have been Capitalized for Period Greater than One Year, Number of Projects 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] Performance Units [Member] Performance Units [Member] Performance Units [Member] 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] 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 Units granted Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period 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 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, Units 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, Units 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 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, shares issued Common Stock, Shares, Issued Fair Value Disclosures [Abstract] 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] Colorado [Member] Colorado [Member] Colorado [Member] 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 Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] Pioneer Southwest [Member] Pioneer Southwest [Member] Relating to Pioneer Southwest. Common Stock [Member] Common Stock [Member] Additional Paid-In Capital [Member] Additional Paid-in Capital [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 Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Beginning Balance, shares Shares, Outstanding Stock Issued During Period, Shares, New Issues Stock Issued During Period, Shares, New Issues 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 Issuance of treasury stock to acquire outstanding PSE units, shares Stock Issued During Period, Shares, Treasury Stock Reissued Issuance of treasury stock to acquire outstanding PSE units Stock Issued During Period, Value, Treasury Stock Reissued Pioneer Southwest merger transaction costs Adjustments to Additional Paid in Capital, Other Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests 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 Net income (loss) Net Income (Loss), Including Portion Attributable to Noncontrolling Interest 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 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 Assets held for sale Disposal Group, Including Discontinued Operation, 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 Liabilities held for sale Disposal Group, Including Discontinued Operation, Liabilities 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] Derivative, by Nature [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] 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] 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] 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 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 [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. 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] Number of Shares granted Forfeitures, number of shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Weighted Average Grant-Date Fair Value, Shares granted Weighted Average Grant-Date Fair Value, Shares vested Debt Disclosure [Abstract] Interest Rate Derivatives [Member] Interest Rate Contract [Member] Cash payments for interest Interest Paid Accretion/amortization of discounts or premiums on loans Amortization of Debt Discount (Premium) Accretion of discount on postretirement benefit obligations Accretion Of Discount On Postretirement Benefit Obligations Accretion Of Discount On Postretirement Benefit Obligations Amortization of capitalized loan fees Amortization of Debt Issuance Costs Net changes in accruals Debt Instrument, Increase, Accrued Interest Interest incurred Interest Costs Incurred Less capitalized interest Interest Costs Capitalized Interest Interest Expense Derivative Financial Instruments Derivative Instruments and Hedging Activities Disclosure [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] Fair Value Disclosures - Nonrecurring [Abstract] Fair Value Disclosures - Nonrecurring [Abstract] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] 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 West Panhandle [Member] West Panhandle [Member] West Panhandle [Member] 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 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] Schedule of Other Ownership Interests [Table] Schedule of Other Ownership Interests [Table] 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] Employee Relocation [Member] Employee Relocation [Member] Contract Termination [Member] Contract Termination [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] 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 Accounts Receivable, Net, Current 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 Proceeds from Issuance of Common Stock Proceeds from Issuance of Common Stock Unrecognized Tax Benefits Unrecognized Tax Benefits Restructuring and Related Cost, Incurred Cost Restructuring and Related Cost, Incurred Cost Restructuring Reserve Restructuring Reserve Restructuring and Related Cost, Expected Cost Restructuring and Related Cost, Cost Incurred to Date Property, Plant and Equipment, Gross Property, Plant and Equipment, Gross Statement of Cash Flows [Abstract] Net Income (Loss) Attributable to Parent Net Income (Loss) Attributable to Parent Cash flows from operating activities: Net Cash Provided by (Used in) Operating Activities [Abstract] 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 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 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 Debt Issuance 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 Increase (Decrease) in Derivative Assets and Liabilities Increase (Decrease) in Derivative Assets and Liabilities Increase Decrease in Investments Increase Decrease in Investments Increase Decrease in Investments 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 Business acquisition Proceeds from investments Proceeds from Sale and Maturity of Held-to-maturity Securities Purchase of investments Payments to Acquire Held-to-maturity Securities 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, end of period Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] 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 2020 Long-term Debt, Maturities, Repayments of Principal in Year Five Thereafter Long-term Debt, Maturities, Repayments of Principal after Year Five Operating Loss Carryforwards [Table] Operating Loss Carryforwards [Table] Income Tax Authority [Axis] Income Tax Authority [Axis] Income Tax Authority [Domain] Income Tax Authority [Domain] Internal Revenue Service (IRS) [Member] Internal Revenue Service (IRS) [Member] Operating Loss Carryforwards [Line Items] Operating Loss Carryforwards [Line Items] Payments for income taxes, net of tax refunds received Income Taxes Paid, Net Unrecognized tax benefit recognized in period Unrecognized tax benefit recognized in period Unrecognized tax benefit recognized in period Acquisitions and Divestitures [Abstract] Acquisitions and Divestitures [Abstract] Schedule of Business Acquisitions, by Acquisition [Table Text Block] Schedule of Business Acquisitions, by Acquisition [Table Text Block] 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] 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] Computer Equipment [Member] Computer Equipment [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Property, Plant and Equipment, Net Property, Plant and Equipment, Net 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 Summary Of Significant Accounting Policies Basis of Presentation and Significant Accounting Policies [Text Block] Document And Entity Information [Abstract] Document and Entity Information [Abstract] Document Information [Table] Document Information [Table] Document Information, Document [Axis] Document Information, Document [Axis] Document [Domain] Document [Domain] Document Information [Line Items] Document Information [Line Items] Entity Registrant Name Entity Registrant Name Trading Symbol Trading Symbol Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Document Type Document Type Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Amendment Flag Amendment Flag Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Voluntary Filers Entity Current Reporting Status Entity Current Reporting Status Entity Public Float Entity Public Float Total Debt To Book Capitalization [Member] Total Debt To Total Capitalization [Member] Total Debt To Total Capitalization [Member] 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] 5.875% Senior Notes Due 2016 [Member] Five Point Eight Seven Five Percent Senior Notes Due Two Thousand Sixteen [Member] Five Point Eight Seven Five Percent Senior Notes Due Two Thousand Sixteen [Member] 6.65% Senior Notes Due 2017 [Member] Six Point Six Five Percent Senior Notes Due Two Thousand Seventeen [Member] Six Point Six Five Percent Senior Notes Due Two Thousand Seventeen [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 Debt instrument, Unamortized Discount and Fee Amounts Debt instrument, Unamortized Discount and Fee Amounts Debt instrument, Unamortized Discount and Fee Amounts Repayments of Long-term Debt Unamortized Debt Issuance Expense Unamortized Debt Issuance Expense 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 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 Derivative Asset, Fair Value, Amount Not Offset Against Collateral Derivative Asset, Fair Value, Amount Not Offset Against Collateral Deferred Compensation Plan Assets Deferred Compensation Plan Assets Assets, Fair Value Disclosure Assets, Fair Value Disclosure Derivative Financial Instruments, Liabilities, Fair Value Disclosure Derivative Liability, Fair Value, Amount Not Offset Against Collateral 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). Related Party Transactions [Abstract] Related Party Transaction [Axis] Related Party Transaction [Axis] Related Party [Domain] Related Party [Domain] Right Of Way [Member] Right Of Way [Member] Right Of Way [Member] Gathering And Treating Fees [Member] Gathering And Treating Fees [Member] Gathering And Treating Fees [Member] Revenue from Related Parties Revenue from Related Parties Proceeds from Equity Method Investment, Dividends or Distributions Proceeds from Equity Method Investment, Dividends or Distributions Cost reimbursement fixed Cost Reimbursement Fixed Cost reimbursement fixed Cost reimbursement variable Cost Reimbursement Variable Cost reimbursement variable Payments to Acquire Property, Plant, and Equipment Payments to Acquire Property, Plant, and Equipment Related party transaction expenses paid Related Party Transaction, Expenses from Transactions with Related Party Capitalized Exploratory Well and Project Activity [Table] Capitalized Exploratory Well and Project Activity [Table] Capitalized Exploratory Well and Project Activity [Table] Project [Axis] Project [Axis] Project [Domain] Project [Domain] Project [Domain] Capitalized exploratory costs [Member] Capitalized exploratory costs [Member] Capitalized exploratory costs [Member] Increase (Decrease) in Capitalized Exploratory Well Costs that are Pending Determination of Proved Reserves [Roll Forward] Increase (Decrease) in Capitalized Exploratory Well Costs that are Pending Determination of Proved Reserves [Roll Forward] Capitalized Exploratory Well Costs, Beginning Balance Capitalized Exploratory Well Cost, Additions Pending Determination of Proved Reserves Capitalized Exploratory Well Cost, Additions Pending Determination of Proved Reserves Reclassification due to determination of proved reserves Reclassification to Well, Facilities, and Equipment Based on Determination of Proved Reserves Capitalized Exploratory Well Cost Assets Disposition Capitalized Exploratory Well Cost Assets Disposition Capitalized Exploratory Well Cost Assets Disposition Exploratory well costs charged to exploration expense Capitalized Exploratory Well Cost, Charged to Expense Capitalized Exploratory Well Costs, Ending Balance Valuation Allowance [Table] Valuation Allowance [Table] Tax Credit Carryforward [Axis] Tax Credit Carryforward [Axis] Tax Credit Carryforward, Name [Domain] Tax Credit Carryforward, Name [Domain] State of Texas Tax Credits [Member] State of Texas Tax Credits [Member] State of Texas Tax Credits [Member] United States Federal Tax Credits [Member] United States Federal Tax Credits [Member] United States Federal Tax Credits [Member] United State Federal Minimum Tax Credits [Member] United State Federal Minimum Tax Credits [Member] United State Federal Minimum Tax Credits [Member] UNITED STATES UNITED STATES 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, Operating Loss Carryforwards [Member] Valuation Allowance, Operating Loss Carryforwards [Member] Valuation Allowance [Line Items] Valuation Allowance [Line Items] Net operating loss carryforward Deferred Tax Assets, Operating Loss Carryforwards Deferred Tax Assets, Tax Credit Carryforwards, Research Deferred Tax Assets, Tax Credit 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 Deferred Tax Assets, Hedging Transactions Deferred Tax Assets, Hedging Transactions 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 Total deferred tax liabilities Deferred Tax Liabilities, Gross, Noncurrent State taxes and other Deferred Tax Liabilities, Other Deferred Tax Liabilities, Net Deferred Tax Liabilities, Net Net deferred tax liability Deferred Tax Assets, Net Deferred income taxes Deferred Tax Assets, Net of Valuation Allowance, Current 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 Commitments And Contingencies Commitments and Contingencies Disclosure [Text Block] Number Of Shares Available Under The Company's Long Term Incentive Plan Number Of Shares Available Under The Company's Long Term Incentive Plan [Table Text Block] Number of shares available under the company's long term incentive plan table text block Schedule Of Employee Stock Purchase Plan Schedule of Share-based Compensation, Employee Stock Purchase Plan, Activity [Table Text Block] Schedule Of Compensation Expense For Each Type Of Incentive Award Schedule Of Compensation Expense For Each Type Of Incentive Award [Table Text Block] Schedule of compensation expense for each type of incentive award table text block Schedule Of Restricted Stock Award Activity Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block] Schedule Of Weighted-Average Assumptions To Estimate The Fair Value Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Schedule Of Stock Options Awards Activity Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block] Schedule of Assumptions Used [Table Text Block] Schedule of Assumptions Used [Table Text Block] Schedule Of Performance Unit Activity Schedule of Nonvested Performance-based Units Activity [Table Text Block] Interest and Other Income [Abstract] Interest And Other Income Interest and Other Income [Table Text Block] 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] 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] Employee Stock [Member] Employee Stock [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. Deferred Compensation Arrangement with Individual, Compensation Expense Deferred Compensation Arrangement with Individual, Compensation Expense 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 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 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 Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Grant Date Fair Value Grant Date Fair Value Grant Date Fair Value Year 1 Transportation Agreements Transportation Fees Future Minimum Payments Due Current Transportation Fees Future Minimum Payments Due Current Year 2 Transportation Agreements Transportation Fees Future Minimum Payments Due In Two Years Transportation Fees Future Minimum Payments Due In Two Years Year 3 Transportation Agreements Transportation Fees Future Minimum Payments Due In Three Years Transportation Fees Future Minimum Payments Due In Three Years Year 4 Transportation Agreements Transportation Fees Future Minimum Payments Due In Four Years Transportation Fees Future Minimum Payments Due In Four Years Year 5 Transportation Agreements Transportation Fees Future Minimum Payments Due In Five Years Transportation Fees Future Minimum Payments Due In Five Years Thereafter Transportation Fees Future Minimum Payments Due In More Than Five Years Transportation Fees Future Minimum Payments Due In More Than Five Years Exploratory Well Costs Oil and Gas Exploration and Production Industries Disclosures [Text Block] Number of Shares, Outstanding at beginning of year Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Number of Options awarded Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures Options exercised Number of Shares, Outstanding and expected to vest at end of year Number of Shares, Exercisable at end of year Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Weighted Average Exercise Price, Outstanding at beginning of year Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Weighted Average Exercise Price, Options awarded Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Weighted Average Exercise Price, Options expired and forfeited Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price Weighted Average Exercise Price, Options exercised Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Weighted Average Exercise Price, Outstanding and expected to vest at end of year Weighted Average Exercise Price, Exercisable at end of year Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Weighted Average Remaining Contractual Life, Outstanding and expected to vest at end of year Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Weighted Average Remaining Contractual Life, Exercisable at end of year Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Aggregate Intrinsic Value, Outstanding and expected to vest at end of year Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Aggregate Intrinsic Value, Exercisable at end of year Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Asset Retirement Obligation [Abstract] Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] Asset Retirement Obligations, Beginning Balance Asset Retirement Obligation AssetRetirementObligationLiabilitiesAcquiredInBusinessCombination AssetRetirementObligationLiabilitiesAcquiredInBusinessCombination AssetRetirementObligationLiabilitiesAcquiredInBusinessCombination Liabilities incurred Asset Retirement Obligation, Liabilities Incurred Changes in estimates Asset Retirement Obligation, Revision of Estimate Liabilities reclassified to discontinued operations held for sale Asset Retirement Obligation Liabilities Reclassified Asset Retirement Obligation Liabilities Reclassified Disposition of wells Asset Retirement Obligations Written Off Through Disposition Of Wells Asset Retirement Obligations Written Off Through Disposition of Wells. Liabilities settled Asset Retirement Obligation, Liabilities Settled Accretion of discount on continuing operations Asset Retirement Obligation Accretion Expense Integrated Services Asset Retirement Obligation Accretion Expense Integrated Services Asset Retirement Obligation Accretion Expense related to Integrated Services Accretion of discount on discontinued operations Asset Retirement Obligation Accretion Expense From Discontinued Operations Included in Asset Retirement Obligation Balance At End of Period Asset Retirement Obligation Accretion Expense From Discontinued Operations Included in Asset Retirement Obligation Balance At End of Period Asset Retirement Obligations, Ending Balance Asset retirement obligations, current portion Asset Retirement Obligation, Current 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] Concentration Risks, Types, No Concentration Percentage [Abstract] Major Customers Concentration Risk Disclosure [Text Block] 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] Cash, Cash Equivalents and Investments [Table Text Block] Cash, Cash Equivalents and Investments [Table Text Block] Income Statement [Abstract] Revenues and other income: Revenues [Abstract] Sales of purchased oil and gas Revenue from Purchased Oil and Gas Interest and other Other Nonoperating Income Derivative gains, net Gain (Loss) on Derivative Instruments, Net, Pretax Gain on disposition of assets, net Revenues Revenues Costs and expenses: Costs and Expenses [Abstract] 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 Other Other Nonoperating Expense Income (loss) from continuing operations before income taxes Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Income (loss) from continuing operations Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest Loss from discontinued operations, net of tax Net income (loss) Net income attributable to noncontrolling interests Net Income (Loss) Attributable to Noncontrolling Interest Net income (loss) attributable to common stockholders 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] 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, Net of Tax, Attributable to Parent Income (loss) from discontinued operations, net of tax Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent 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] Investments Investments Long-term Debt, Current Maturities Long-term Debt, Current Maturities Long-term Debt, Excluding Current Maturities Long-term Debt, Excluding Current Maturities Interest And Other Income Other Income and Other Expense Disclosure [Text Block] Risks and Uncertainties [Abstract] Concentration Risk [Table] Concentration Risk [Table] Occidental Energy Marketing Inc [Member] Occidental Energy Marketing Inc [Member] Occidental Energy Marketing Inc Plains Marketing LP [Member] Plains Marketing Lp [Member] Plains Marketing LP [Member] Exxon Mobil [Member] Exxon Mobil [Member] Exxon Mobil [Member] BP Corporation North America [Member] BP Corporation North America [Member] BP Corporation North America [Member] Valero Marketing and Supply Company [Member] Valero Marketing and Supply Company [Member] Valero Marketing and Supply Company [Member] Lonestar/Oneok [Member] Lonestar/Oneok [Member] Lonestar/Oneok [Member] EDF Trading North America [Member] EDF Trading North America [Member] EDF Trading North America [Member] Concentration Risk Type [Axis] Concentration Risk Type [Axis] Concentration Risk Type [Domain] Concentration Risk Type [Domain] Sales of Purchased Oil and Gas [Member] Sales of Purchased Oil and Gas [Member] Sales of Purchased Oil and Gas [Member] Concentration Risk [Line Items] Concentration Risk [Line Items] Concentration Risk, Percentage Concentration Risk, Percentage Approved and authorized shares Shares issued Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period Disclosures About Fair Value Measurements Fair Value Disclosures [Text Block] Asset Retirement Obligations Asset Retirement Obligation Disclosure [Text Block] Maximum [Member] Maximum [Member] Minimum [Member] Minimum [Member] Risk-free interest rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Range of volatilities Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Weighted Average Volatility Rate 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] Income Taxes Income Tax Disclosure [Text Block] Net Income (Loss) Per Share Attributable To Common Stockholders Earnings Per Share [Text Block] 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] Commodity Price Derivatives [Member] Commodity Contract [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, Current Derivative Asset, Noncurrent Derivative Asset, Noncurrent Derivative Liability, Current Derivative Liability, Current Derivative Liability, Noncurrent Derivative Liability, Noncurrent Disclosure of Compensation Related Costs, Share-based Payments [Abstract] 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] Income Tax (Expense) Benefit 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 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] Fair Value of Assets Classified as Held for Sale [Abstract] Fair Value of Assets Classified as Held for Sale [Abstract] Long Lived Assets Held-for-sale by Asset Type [Axis] Long Lived Assets Held-for-sale by Asset Type [Axis]