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Income Taxes (Tax effects of temporary differences) (Details) (USD $)
In Thousands, unless otherwise specified |
Dec. 31, 2014
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Sep. 30, 2014
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Jun. 30, 2014
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Mar. 31, 2014
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Dec. 31, 2013
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|---|---|---|---|---|---|
| Current deferred tax assets, net of current deferred tax liability: | |||||
| Net operating loss carryforwards | $ 44,250gncma_DeferredTaxAssetsTaxCreditCarryforwardsCurrent | $ 30,344gncma_DeferredTaxAssetsTaxCreditCarryforwardsCurrent | |||
| Compensated absences, accrued for financial reporting purposes | 3,117us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsCompensatedAbsences | 2,956us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsCompensatedAbsences | |||
| Workers compensation and self-insurance health reserves, principally due to accrual for financial reporting purposes | 2,043us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsSelfInsurance | 1,688us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsSelfInsurance | |||
| Accounts receivable, principally due to allowance for doubtful receivables | 2,585us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts | 1,154us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts | |||
| Deferred revenue for financial reporting purposes | 2,525gncma_DeferredTaxAssetsDeferredIncomeCurrent | 2,673gncma_DeferredTaxAssetsDeferredIncomeCurrent | |||
| Other | 1,600gncma_DeferredTaxAssetsOtherCurrent | 938gncma_DeferredTaxAssetsOtherCurrent | |||
| Total current deferred tax assets | 56,120us-gaap_DeferredTaxAssetsNetCurrent | 39,753us-gaap_DeferredTaxAssetsNetCurrent | |||
| Long-term deferred tax assets: | |||||
| Net operating loss carryforwards | 87,688gncma_DeferredTaxAssetsTaxCreditCarryforwardsNoncurrent | 90,589gncma_DeferredTaxAssetsTaxCreditCarryforwardsNoncurrent | |||
| Deferred revenue for financial reporting purposes | 33,552gncma_DeferredTaxAssetsDeferredIncomeNoncurrent | 35,506gncma_DeferredTaxAssetsDeferredIncomeNoncurrent | |||
| Alternative minimum tax credits | 1,735us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsAlternativeMinimumTax | 1,895us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsAlternativeMinimumTax | |||
| Deferred compensation expense for tax purposes in excess of amounts recognized for financial reporting purposes | 1,374gncma_DeferredTaxAssetsTaxDeferredExpenseDeferredCompensationNoncurrent | 2,556gncma_DeferredTaxAssetsTaxDeferredExpenseDeferredCompensationNoncurrent | |||
| Asset retirement obligations in excess of amounts recognized for tax purposes | 6,660us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAssetRetirementObligations | 4,930us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAssetRetirementObligations | |||
| Share-based compensation expense for financial reporting purposes in excess of amounts recognized for tax purposes | 1,458us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost | 1,860us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost | |||
| Other | 4,266gncma_DeferredTaxAssetsOtherNoncurrent | 4,335gncma_DeferredTaxAssetsOtherNoncurrent | |||
| Total long-term deferred tax assets | 136,733us-gaap_DeferredTaxAssetsNetNoncurrent | 141,671us-gaap_DeferredTaxAssetsNetNoncurrent | |||
| Long-term deferred tax liabilities: | |||||
| Plant and equipment, principally due to differences in depreciation | 231,109us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment | 212,719us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment | |||
| Intangible assets | 48,768us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets | 49,761us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets | |||
| Flow-through entity deferred tax items | 44,728us-gaap_DeferredTaxLiabilitiesTaxDeferredIncome | 40,667us-gaap_DeferredTaxLiabilitiesTaxDeferredIncome | |||
| Total long-term deferred tax liabilities | 324,605us-gaap_DeferredIncomeTaxLiabilities | 303,147us-gaap_DeferredIncomeTaxLiabilities | |||
| Net long-term deferred tax liabilities | $ 187,872us-gaap_DeferredTaxLiabilitiesNoncurrent | $ 166,605us-gaap_DeferredTaxLiabilitiesNoncurrent | $ 169,874us-gaap_DeferredTaxLiabilitiesNoncurrent | $ 159,085us-gaap_DeferredTaxLiabilitiesNoncurrent | $ 161,476us-gaap_DeferredTaxLiabilitiesNoncurrent |
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- Definition
Deferred Tax Assets, Deferred Income, Current No definition available.
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- Definition
Deferred Tax Assets, Deferred Income, Noncurrent No definition available.
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- Details
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- Details
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- Definition
Deferred Tax Assets, Other, Current No definition available.
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- Definition
Deferred Tax Assets, Other, Noncurrent No definition available.
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- Definition
Deferred Tax Assets, Tax Credit Carryforwards, Current No definition available.
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- Definition
Deferred Tax Assets, Tax Credit Carryforwards, Noncurrent No definition available.
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- Definition
Deferred Tax Assets Tax Deferred Expense Deferred Compensation, Noncurrent No definition available.
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- Definition
Amount of deferred tax liability attributable to taxable temporary differences. 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 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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| X | ||||||||||
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- Definition
Amount after allocation of valuation allowances of noncurrent deferred tax asset attributable to deductible temporary differences and carryforwards. 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
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible alternative minimum tax credit carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from compensated absences (includes, but not limited to, sick and personal days). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from the allowance for doubtful accounts. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from asset retirement obligations. An asset retirement obligation is a legal obligation associated with the disposal or retirement from service of a tangible long-lived asset. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from estimated losses under self insurance. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of deferred tax liability attributable to taxable temporary differences from intangible assets other than goodwill. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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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 of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
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- Definition
Amount of deferred tax liability attributable to taxable temporary differences from tax deferred revenue or other income not separately disclosed. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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