2.2.0.7 false Consolidated Balance Sheets (Unaudited) (USD $) 0110 - Statement - Consolidated Balance Sheets (Unaudited) true false In Thousands false false 1 USD false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 USDEPS Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ false 2 USD false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ 4 Current assets: 2 us-gaap_AssetsCurrentAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 5 Cash and cash equivalents 3 us-gaap_CashAndCashEquivalentsAtCarryingValue us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 true true false false 383000 383 false false false 2 true true false false 3234000 3234 false false false xbrli:monetaryItemType monetary Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits should not be reported as cash and cash equivalents. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 7, 26 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 8, 9 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 7 -Footnote 1 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 false 6 Accounts receivable, net of allowance for doubtful accounts: 3 us-gaap_ReceivablesNetCurrentAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 7 Oil and natural gas 4 cxo_OilAndGasSalesReceivable cxo false debit instant Oil And Gas Sales Receivable. false false false false false false false false false false false verboselabel false 1 false true false false 88029000 88029 false false false 2 false true false false 69199000 69199 false false false xbrli:monetaryItemType monetary Oil And Gas Sales Receivable. No authoritative reference available. false 8 Joint operations and other 4 us-gaap_OilAndGasJointInterestBillingReceivablesCurrent us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 88836000 88836 false false false 2 false true false false 100120000 100120 false false false xbrli:monetaryItemType monetary Current portion of accounts receivable attributable to joint interest partners in oil and gas properties. These are billings to the non-operators associated with the operation of wells and are based on those owners' working interests in the wells. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-OGP -Chapter 1 -Paragraph 22 false 9 Related parties 4 us-gaap_AccountsReceivableRelatedPartiesCurrent us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 395000 395 false false false 2 false true false false 216000 216 false false false xbrli:monetaryItemType monetary Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph k -Subparagraph 1 -Article 4 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 57 -Paragraph 2 -Subparagraph d Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 3 -Subparagraph a -Article 5 false 10 Derivative instruments 4 us-gaap_DerivativeAssetsCurrent us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 32409000 32409 false false false 2 false true false false 1309000 1309 false false false xbrli:monetaryItemType monetary Fair values as of the balance sheet date for all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments and which are expected to be converted into cash or otherwise disposed of within a year or the normal operating cycle, if longer, net of the effects of master netting arrangements. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 4, 17 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 10 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 43 -Chapter 3 -Section A -Paragraph 4 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FIN39-1 -Paragraph 10A, 10B false 11 Deferred income taxes 4 us-gaap_DeferredTaxAssetsNetCurrent us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 0 0 false false false 2 false true false false 29284000 29284 false false false xbrli:monetaryItemType monetary The current portion of the aggregate tax effects as of the balance sheet date of all future tax deductions arising from temporary differences between tax basis and generally accepted accounting principles basis recognition of assets, liabilities, revenues and expenses, which can only be deducted for tax purposes when permitted under enacted tax laws; after deducting the allocated valuation allowance, if any, to reduce such amount to net realizable value. Deferred tax liabilities and assets shall be classified as current or noncurrent based on the classification of the related asset or liability for financial reporting. A deferred tax liability or asset that is not related to an asset or liability for financial reporting, including deferred tax assets related to carryforwards, shall be classified according to the expected reversal date of the temporary difference. An unrecognized tax benefit that is directly related to a position taken in a tax year that results in a net operating loss carryforward should be presented as a reduction of the related deferred tax asset. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 41, 42, 43 false 12 Prepaid costs and other 4 cxo_PrepaidCostsAndOthers cxo false debit instant Prepaid costs and other. false false false false false false false false false false false totallabel false 1 false true false false 10600000 10600 false false false 2 false true false false 13896000 13896 false false false xbrli:monetaryItemType monetary Prepaid costs and other. No authoritative reference available. true 13 Total current assets 3 us-gaap_AssetsCurrent us-gaap true debit instant No definition available. false false false false false false false false false false false totallabel false 1 false true false false 220652000 220652 false false false 2 false true false false 217258000 217258 false false false xbrli:monetaryItemType monetary Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold, or consumed within one year (or the normal operating cycle, if longer). Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 9 -Article 5 true 14 Property and equipment, at cost: 2 us-gaap_PropertyPlantAndEquipmentNetAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 15 Oil and natural gas properties, successful efforts method 3 us-gaap_OilAndGasPropertySuccessfulEffortMethodGross us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 3697653000 3697653 false false false 2 false true false false 3358004000 3358004 false false false xbrli:monetaryItemType monetary Oil and Gas properties, gross, carried under the successful effort method. No authoritative reference available. false 16 Accumulated depletion and depreciation 3 us-gaap_OilAndGasPropertySuccessfulEffortMethodAccumulatedDepreciationDepletionAndAmortization us-gaap true credit instant No definition available. false false false false false false false false false false true negatedtotal false 1 false true false false -630255000 -630255 false false false 2 false true false false -517421000 -517421 false false false xbrli:monetaryItemType monetary Accumulated depreciation, depletion and amortization of oil and gas property carried under the successful effort method. No authoritative reference available. true 17 Total oil and natural gas properties, net 3 us-gaap_OilAndGasPropertySuccessfulEffortMethodNet us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 3067398000 3067398 false false false 2 false true false false 2840583000 2840583 false false false xbrli:monetaryItemType monetary Oil and Gas properties net of accumulated DD&A, Impairment and Abandonment, carried under the successful effort method. No authoritative reference available. false 18 Other property and equipment, net 3 us-gaap_PropertyPlantAndEquipmentOther us-gaap true debit instant No definition available. false false false false false false false false false false false totallabel false 1 false true false false 16304000 16304 false false false 2 false true false false 15706000 15706 false false false xbrli:monetaryItemType monetary This element represents capitalized assets classified as property, plant and equipment not otherwise defined in the taxonomy. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 5 true 19 Total property and equipment, net 3 us-gaap_PropertyPlantAndEquipmentNet us-gaap true debit instant No definition available. false false false false false false false false false false false totallabel false 1 false true false false 3083702000 3083702 false false false 2 false true false false 2856289000 2856289 false false false xbrli:monetaryItemType monetary Tangible assets that are held by an entity for use in the production or supply of goods and services, for rental to others, or for administrative purposes and that are expected to provide economic benefit for more than one year; net of accumulated depreciation. Examples include land, buildings, and production equipment. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 13 -Subparagraph a -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 12 -Paragraph 5 -Subparagraph b, c Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 8 -Article 7 true 20 Deferred loan costs, net 2 us-gaap_DeferredFinanceCostsNoncurrentNet us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 20771000 20771 false false false 2 false true false false 20676000 20676 false false false xbrli:monetaryItemType monetary Net amount of long-term deferred finance costs capitalized at the end of the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 21 -Paragraph 16 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 17 -Article 5 false 21 Intangible asset, net - operating rights 2 us-gaap_FiniteLivedIntangibleAssetsNet us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 35748000 35748 false false false 2 false true false false 36522000 36522 false false false xbrli:monetaryItemType monetary The aggregate sum of gross carrying value of a major finite-lived intangible asset class, less accumulated amortization and any impairment charges. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 142 -Paragraph 45 -Subparagraph a(1) false 22 Inventory 2 us-gaap_InventoryNoncurrent us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 20258000 20258 false false false 2 false true false false 16255000 16255 false false false xbrli:monetaryItemType monetary Inventories not expected to be converted to cash, sold or exchanged within the normal operating cycle. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 43 -Chapter 3 -Section A -Paragraph 4, 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 6 -Subparagraph d -Article 5 false 23 Noncurrent derivative instruments 2 us-gaap_DerivativeInstrumentsAndHedgesNoncurrent us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 62164000 62164 false false false 2 false true false false 23614000 23614 false false false xbrli:monetaryItemType monetary Carrying amount as of the balance sheet date of the assets arising from derivative contracts and hedging activities, which are expected to be converted into cash or otherwise disposed of after a year or beyond the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 4 false 24 Other assets 2 us-gaap_OtherAssetsNoncurrent us-gaap true debit instant No definition available. false false false false false false false false false false false totallabel false 1 false true false false 958000 958 false false false 2 false true false false 471000 471 false false false xbrli:monetaryItemType monetary Aggregate carrying amount, as of the balance sheet date, of noncurrent assets not separately disclosed in the balance sheet due to materiality considerations. Noncurrent assets are expected to be realized or consumed after one year (or the normal operating cycle, if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 17 -Article 5 true 25 Total assets 2 us-gaap_Assets us-gaap true debit instant No definition available. false false false false false false false false false false false totallabel false 1 false true false false 3444253000 3444253 false false false 2 false true false false 3171085000 3171085 false false false xbrli:monetaryItemType monetary Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Concepts (CON) -Number 6 -Paragraph 25 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 18 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 12 -Article 7 true 28 Accounts payable: 3 us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 29 Trade 4 us-gaap_AccountsPayableTradeCurrent us-gaap true credit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 5982000 5982 false false false 2 false true false false 15443000 15443 false false false xbrli:monetaryItemType monetary Carrying value as of the balance sheet date of obligations incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Subparagraph a -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 43 -Chapter 3 -Section A -Paragraph 7 false 30 Related parties 4 us-gaap_DueToRelatedPartiesCurrent us-gaap true credit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 852000 852 false false false 2 false true false false 291000 291 false false false xbrli:monetaryItemType monetary Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Subparagraph a -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph k -Subparagraph 1 -Article 4 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 57 -Paragraph 2 -Subparagraph d false 31 Other current liabilities: 3 us-gaap_OtherLiabilitiesCurrentAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 32 Bank overdrafts 4 us-gaap_BankOverdrafts us-gaap true credit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 37992000 37992 false false false 2 false true false false 3415000 3415 false false false xbrli:monetaryItemType monetary Carrying value as of the balance sheet date of payments made in excess of existing cash balances, which will be honored by the bank but reflected as a loan to the entity. Overdrafts generally have a very short time frame for correction or repayment and are therefore more similar to short-term bank financing than trade financing. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 43 -Chapter 3 -Section A -Paragraph 7 false 33 Revenue payable 4 us-gaap_OilAndGasSalesPayableCurrent us-gaap true credit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 30172000 30172 false false false 2 false true false false 31069000 31069 false false false xbrli:monetaryItemType monetary Carrying value as of the balance sheet date of obligations incurred and payable to third parties for oil and gas that has been sold but not delivered. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Subparagraph a -Article 5 false 34 Accrued and prepaid drilling costs 4 cxo_AccruedAndPrepaidDrillingCosts cxo false credit instant Accrued and prepaid drilling costs. false false false false false false false false false false false verboselabel false 1 false true false false 190719000 190719 false false false 2 false true false false 164282000 164282 false false false xbrli:monetaryItemType monetary Accrued and prepaid drilling costs. No authoritative reference available. false 35 Derivative instruments 4 us-gaap_DerivativeInstrumentsAndHedgesLiabilities us-gaap true credit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 18093000 18093 false false false 2 false true false false 62419000 62419 false false false xbrli:monetaryItemType monetary Sum as of the balance sheet date of the (a) fair values of all liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, and (b) the carrying amounts of the liabilities arising from financial instruments or contracts used to mitigate a specified risk (hedge), and which are expected to be extinguished or otherwise disposed of within a year or the normal operating cycle, if longer, net of the effects of master netting arrangements. No authoritative reference available. false 36 Deferred income taxes 4 us-gaap_DeferredTaxLiabilitiesCurrent us-gaap true credit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 3530000 3530 false false false 2 false true false false 0 0 false false false xbrli:monetaryItemType monetary Represents the current portion of deferred tax liabilities, which result from applying the applicable tax rate to net taxable temporary differences pertaining to each jurisdiction to which the entity is obligated to pay income tax. A current taxable temporary difference is a difference between the tax basis and the carrying amount of a current asset or liability in the financial statements prepared in accordance with generally accepted accounting principles. In a classified statement of financial position, an enterprise shall separate deferred tax liabilities and assets into a current amount and a noncurrent amount. Deferred tax liabilities and assets shall be classified as current or noncurrent based on the classification of the related asset or liability for financial reporting. A deferred tax liability or asset that is not related to an asset or liability for financial reporting, including deferred tax assets related to carryforwards, shall be classified according to the expected reversal date of the temporary difference. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 41, 42, 43 false 37 Other current liabilities 4 us-gaap_OtherLiabilitiesCurrent us-gaap true credit instant No definition available. false false false false false false false false false false false totallabel false 1 false true false false 60308000 60308 false false false 2 false true false false 60095000 60095 false false false xbrli:monetaryItemType monetary Aggregate carrying amount, as of the balance sheet date, of current obligations not separately disclosed in the balance sheet due to materiality considerations. Current liabilities are expected to be paid within one year (or the normal operating cycle, if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 43 -Chapter 3 -Section A -Paragraph 8 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 6 -Paragraph 15 true 38 Total current liabilities 3 us-gaap_LiabilitiesCurrent us-gaap true credit instant No definition available. false false false false false false false false false false false totallabel false 1 false true false false 347648000 347648 false false false 2 false true false false 337014000 337014 false false false xbrli:monetaryItemType monetary Total obligations incurred as part of normal operations that are expected to be paid during the following twelve months or within one business cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 21 -Article 5 true 39 Long-term debt 2 us-gaap_LongTermDebtNoncurrent us-gaap true credit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 644023000 644023 false false false 2 false true false false 845836000 845836 false false false xbrli:monetaryItemType monetary Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 false 40 Deferred income taxes 2 us-gaap_DeferredTaxLiabilitiesNoncurrent us-gaap true credit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 664222000 664222 false false false 2 false true false false 603286000 603286 false false false xbrli:monetaryItemType monetary Represents the noncurrent portion of deferred tax liabilities, which result from applying the applicable tax rate to net taxable temporary differences pertaining to each jurisdiction to which the entity is obligated to pay income tax. A noncurrent taxable temporary difference is a difference between the tax basis and the carrying amount of a noncurrent asset or liability in the financial statements prepared in accordance with generally accepted accounting principles. In a classified statement of financial position, an enterprise shall separate deferred tax liabilities and assets into a current amount and a noncurrent amount. Deferred tax liabilities and assets shall be classified as current or noncurrent based on the classification of the related asset or liability for financial reporting. A deferred tax liability or asset that is not related to an asset or liability for financial reporting, including deferred tax assets related to carryforwards, shall be classified according to the expected reversal date of the temporary difference. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 41, 42 false 41 Noncurrent derivative instruments 2 us-gaap_DerivativeLiabilitiesNoncurrent us-gaap true credit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 5678000 5678 false false false 2 false true false false 29337000 29337 false false false xbrli:monetaryItemType monetary Fair values as of the balance sheet date of all liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, and which are expected to be extinguished or otherwise disposed of after one year or beyond the normal operating cycle, if longer, net of the effects of master netting arrangements. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 4, 17 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 43 -Chapter 3 -Section A -Paragraph 7 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 10 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FIN39-1 -Paragraph 10A, 10B false 42 Asset retirement obligations and other long-term liabilities 2 us-gaap_OtherLiabilitiesNoncurrent us-gaap true credit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 20335000 20335 false false false 2 false true false false 20184000 20184 false false false xbrli:monetaryItemType monetary Aggregate carrying amount, as of the balance sheet date, of noncurrent obligations not separately disclosed in the balance sheet due to materiality considerations. Noncurrent liabilities are expected to be paid after one year (or the normal operating cycle, if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 24 -Article 5 false 43 Commitments and contingencies (Note K) 2 us-gaap_CommitmentsAndContingencies2009 us-gaap true na duration No definition available. false false false false false false false false false false false verboselabel false 1 false false false false 0 0     false false false 2 false false false false 0 0     false false false xbrli:stringItemType string Represents the caption on the face of the balance sheet to indicate that the entity has entered into (1) purchase or supply arrangements that will require expending a portion of its resources to meet the terms thereof, and (2) is exposed to potential losses or, less frequently, gains, arising from (a) possible claims against a company's resources due to future performance under contract terms, and (b) possible losses or likely gains from uncertainties that will ultimately be resolved when one or more future events that are deemed likely to occur do occur or fail to occur. This caption alerts the reader that one or more notes to the financial statements disclose pertinent information about the entity's commitments and contingencies. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 19 -Article 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 5 -Paragraph 8, 9 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 25 -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 17 -Article 9 false 44 Stockholders' equity: 2 us-gaap_StockholdersEquityAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 45 Common stock, $0.001 par value; 300,000,000 authorized; 91,851,690 and 85,815,926 shares issued at June 30, 2010 and December 31, 2009, respectively 3 us-gaap_CommonStockValue us-gaap true credit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 92000 92 false false false 2 false true false false 86000 86 false false false xbrli:monetaryItemType monetary Dollar value of issued common stock whether issued at par value, no par or stated value. This item includes treasury stock repurchased by the entity. Note: elements for number of common shares, par value and other disclosure concepts are in another section within stockholders' equity. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 30 -Article 5 false 46 Additional paid-in capital 3 us-gaap_AdditionalPaidInCapitalCommonStock us-gaap true credit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 1265179000 1265179 false false false 2 false true false false 1029392000 1029392 false false false xbrli:monetaryItemType monetary Value received from shareholders in common stock-related transactions that are in excess of par value or stated value and amounts received from other stock-related transactions. Includes only common stock transactions (excludes preferred stock transactions). May be called contributed capital, capital in excess of par, capital surplus, or paid-in capital. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 31 -Article 5 false 47 Retained earnings 3 us-gaap_RetainedEarningsAccumulatedDeficit us-gaap true credit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 498078000 498078 false false false 2 false true false false 306367000 306367 false false false xbrli:monetaryItemType monetary The cumulative amount of the reporting entity's undistributed earnings or deficit. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 10 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 31 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 false 48 Treasury stock, at cost; 23,667 and 12,380 shares at June 30, 2010 and December 31, 2009, respectively 3 us-gaap_TreasuryStockValue us-gaap true debit instant No definition available. false false false false false false false false false false true negatedtotal false 1 false true false false -1002000 -1002 false false false 2 false true false false -417000 -417 false false false xbrli:monetaryItemType monetary Value of common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury. Treasury stock is issued but is not outstanding. This stock has no voting rights and receives no dividends. Note that treasury stock may be recorded at its total cost or separately as par (or stated) value and additional paid in capital. Note: number of treasury shares concept is in another section within stockholders' equity. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Technical Bulletin (FTB) -Number 85-6 -Paragraph 3 true 49 Total stockholders' equity 2 us-gaap_StockholdersEquity us-gaap true credit instant No definition available. false false false false false false false false false false false totallabel false 1 false true false false 1762347000 1762347 false false false 2 false true false false 1335428000 1335428 false false false xbrli:monetaryItemType monetary Total of all Stockholders' Equity (deficit) items, net of receivables from officers, directors owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A3 -Appendix A Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 4 -Section E Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30, 31 -Article 5 true 50 Total liabilities and stockholders' equity 2 us-gaap_LiabilitiesAndStockholdersEquity us-gaap true credit instant No definition available. false false false false false false false false false false false totallabel false 1 true true false false 3444253000 3444253 false false false 2 true true false false 3171085000 3171085 false false false xbrli:monetaryItemType monetary Total of all Liabilities and Stockholders' Equity items. 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