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Consolidated Balance Sheets (USD $)
In Thousands, unless otherwise specified |
Dec. 31, 2014
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Dec. 31, 2013
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|---|---|---|
| Current assets: | ||
| Cash and cash equivalents | $ 23,666us-gaap_CashAndCashEquivalentsAtCarryingValue | $ 15,800us-gaap_CashAndCashEquivalentsAtCarryingValue |
| Receivables: | ||
| Oil and natural gas sales | 67,242us-gaap_AccountsReceivableNetCurrent | 96,752us-gaap_AccountsReceivableNetCurrent |
| Joint interest and other | 43,645us-gaap_OilAndGasJointInterestBillingReceivables | 31,104us-gaap_OilAndGasJointInterestBillingReceivables |
| Total receivables | 110,887us-gaap_ReceivablesNetCurrent | 127,856us-gaap_ReceivablesNetCurrent |
| Deferred income taxes | 11,662us-gaap_DeferredTaxAssetsLiabilitiesNetCurrent | 584us-gaap_DeferredTaxAssetsLiabilitiesNetCurrent |
| Prepaid expenses and other assets | 36,347us-gaap_PrepaidExpenseAndOtherAssetsCurrent | 29,362us-gaap_PrepaidExpenseAndOtherAssetsCurrent |
| Total current assets | 182,562us-gaap_AssetsCurrent | 173,602us-gaap_AssetsCurrent |
| Property and equipment - at cost: | ||
| Oil and natural gas properties and equipment (full cost method, of which $109,824 at December 31, 2014 and $116,612 at December 31, 2013 were excluded from amortization) | 8,045,666us-gaap_OilAndGasPropertyFullCostMethodGross | 7,339,097us-gaap_OilAndGasPropertyFullCostMethodGross |
| Furniture, fixtures and other | 23,269us-gaap_FurnitureAndFixturesGross | 21,431us-gaap_FurnitureAndFixturesGross |
| Total property and equipment | 8,068,935us-gaap_PropertyPlantAndEquipmentGross | 7,360,528us-gaap_PropertyPlantAndEquipmentGross |
| Less accumulated depreciation, depletion and amortization | 5,575,078us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment | 5,084,704us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment |
| Net property and equipment | 2,493,857us-gaap_PropertyPlantAndEquipmentNet | 2,275,824us-gaap_PropertyPlantAndEquipmentNet |
| Restricted deposits for asset retirement obligations | 15,444us-gaap_RestrictedCashAndInvestmentsNoncurrent | 37,421us-gaap_RestrictedCashAndInvestmentsNoncurrent |
| Other assets | 17,244us-gaap_OtherAssetsNoncurrent | 20,455us-gaap_OtherAssetsNoncurrent |
| Total assets | 2,709,107us-gaap_Assets | 2,507,302us-gaap_Assets |
| Current liabilities: | ||
| Accounts payable | 194,109us-gaap_AccountsPayableCurrent | 145,212us-gaap_AccountsPayableCurrent |
| Undistributed oil and natural gas proceeds | 37,009us-gaap_OilAndGasSalesPayableCurrent | 42,107us-gaap_OilAndGasSalesPayableCurrent |
| Asset retirement obligations | 36,003us-gaap_AssetRetirementObligationCurrent | 77,785us-gaap_AssetRetirementObligationCurrent |
| Accrued liabilities | 17,377us-gaap_AccruedLiabilitiesCurrent | 28,000us-gaap_AccruedLiabilitiesCurrent |
| Total current liabilities | 284,498us-gaap_LiabilitiesCurrent | 293,104us-gaap_LiabilitiesCurrent |
| Long-term debt, less current maturities | 1,360,057us-gaap_LongTermDebtNoncurrent | 1,205,421us-gaap_LongTermDebtNoncurrent |
| Asset retirement obligations, less current portion | 354,565us-gaap_AssetRetirementObligationsNoncurrent | 276,637us-gaap_AssetRetirementObligationsNoncurrent |
| Deferred income taxes | 186,988us-gaap_DeferredTaxLiabilitiesNoncurrent | 178,142us-gaap_DeferredTaxLiabilitiesNoncurrent |
| Other liabilities | 13,691us-gaap_OtherLiabilitiesNoncurrent | 13,388us-gaap_OtherLiabilitiesNoncurrent |
| Commitments and contingencies | ||
| Shareholders' equity: | ||
| Preferred stock, $0.00001 par value; 20,000,000 shares authorized; 0 issued at December 31, 2014 and 2013 | ||
| Common stock, $0.00001 par value; 118,330,000 shares authorized; 78,768,588 issued and 75,899,415 outstanding at December 31, 2014; 78,460,872 issued and 75,591,699 outstanding at December 31, 2013 | 1us-gaap_CommonStockValue | 1us-gaap_CommonStockValue |
| Additional paid-in capital | 414,580us-gaap_AdditionalPaidInCapitalCommonStock | 403,564us-gaap_AdditionalPaidInCapitalCommonStock |
| Retained earnings | 118,894us-gaap_RetainedEarningsAccumulatedDeficit | 161,212us-gaap_RetainedEarningsAccumulatedDeficit |
| Treasury stock, at cost | (24,167)us-gaap_TreasuryStockValue | (24,167)us-gaap_TreasuryStockValue |
| Total shareholders' equity | 509,308us-gaap_StockholdersEquity | 540,610us-gaap_StockholdersEquity |
| Total liabilities and shareholders' equity | $ 2,709,107us-gaap_LiabilitiesAndStockholdersEquity | $ 2,507,302us-gaap_LiabilitiesAndStockholdersEquity |
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- Definition
Carrying value as of the balance sheet date of liabilities 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
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- Definition
Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. 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
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- Definition
Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
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
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- Definition
Current portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Noncurrent portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
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
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- Definition
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
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- Details
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- Definition
Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences expected to be realized or consumed within one year or operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of deferred tax liability attributable to taxable temporary differences, net of deferred tax asset attributable to deductible temporary differences and carryforwards net of valuation allowances 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
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- Definition
Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of liabilities and equity items, including the portion of equity attributable to noncontrolling interests, if any. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
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
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- Details
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- Definition
Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Oil and gas properties, gross, carried under the full cost method. No definition available.
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- Definition
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
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- Definition
Aggregate carrying amount, as of the balance sheet date, of noncurrent assets not separately disclosed in the balance sheet. 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
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- Definition
Aggregate carrying amount, as of the balance sheet date, of noncurrent obligations not separately disclosed in the balance sheet. 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
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- Definition
Aggregate par or stated value of issued nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable preferred shares, par value and other disclosure concepts are in another section within stockholders' equity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
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- Definition
Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
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- Definition
Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
The noncurrent cash, cash equivalents and investments that is restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits classified as long-term; that is not expected to be released from such existing restrictions within one year of the balance sheet date or operating cycle, whichever is longer. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. Includes noncurrent cash equivalents and investments that are similarly restricted as to withdrawal, usage or disposal. No definition available.
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- Definition
The cumulative amount of the reporting entity's undistributed earnings or deficit. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
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
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- Details
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- Definition
The amount allocated to treasury stock. Treasury stock is common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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