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Income Taxes (Details 3) (USD $)
In Millions, unless otherwise specified |
Dec. 31, 2014
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Dec. 31, 2013
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| Components Of Deferred Income Tax (Liabilities)/Assets [Abstract] | ||
| Deferred income tax liabilities - property | $ (15,173)us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment | $ (14,448)us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment |
| Deferred income tax liabilities - other | (411)us-gaap_DeferredTaxLiabilitiesOther | (260)us-gaap_DeferredTaxLiabilitiesOther |
| Total deferred income tax liabilities | (15,584)us-gaap_DeferredIncomeTaxLiabilities | (14,708)us-gaap_DeferredIncomeTaxLiabilities |
| Deferred income tax asset - accrued wages | 74us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation | 71us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation |
| Deferred income tax asset - accrued casualty costs | 228us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves | 223us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves |
| Deferred income tax asset - accrued stock compensation | 69us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost | 66us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost |
| Deferred income tax asset - debt and leases | 86unp_DeferredTaxAssetsTaxDeferredExpenseReservesAccrualsDebtLeases | 41unp_DeferredTaxAssetsTaxDeferredExpenseReservesAccrualsDebtLeases |
| Deferred income tax asset - retiree benefits | 392unp_DeferredTaxAssetsTaxDeferredExpenseCompensationBenefitsPensionsPostretirementBenefits | 100unp_DeferredTaxAssetsTaxDeferredExpenseCompensationBenefitsPensionsPostretirementBenefits |
| Deferred income tax asset - credits | 164us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsOther | 182us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsOther |
| Deferred income tax asset - other | 168us-gaap_DeferredTaxAssetsOther | 130us-gaap_DeferredTaxAssetsOther |
| Total deferred income tax asset | 1,181us-gaap_DeferredTaxAssetsNet | 813us-gaap_DeferredTaxAssetsNet |
| Net deferred income tax liability | (14,403)us-gaap_DeferredTaxLiabilities | (13,895)us-gaap_DeferredTaxLiabilities |
| Current portion of deferred taxes | 277us-gaap_DeferredTaxAssetsNetCurrent | 268us-gaap_DeferredTaxAssetsNetCurrent |
| Non-current portion of deferred taxes | (14,680)us-gaap_DeferredTaxLiabilitiesNoncurrent | (14,163)us-gaap_DeferredTaxLiabilitiesNoncurrent |
| Income Tax Details [Abstract] | ||
| Deferred tax valuation allowance | $ 0us-gaap_DeferredTaxAssetsValuationAllowance | $ 0us-gaap_DeferredTaxAssetsValuationAllowance |
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- Definition
The tax effect as of the balance sheet date of the amount of estimated future tax deductions arising from pension and postretirement benefits, which can only be deducted for tax purposes when actual costs are incurred, and which can only be realized if sufficient tax-basis income is generated in future periods to enable the deduction to be taken. No definition available.
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- Definition
The tax effect as of the balance sheet date of the amount of the estimated future tax deductions arising from debt and leases, which are deducted for tax purposes when paid, and which can only be realized if sufficient tax-basis income is generated in future periods to enable the deduction to be taken. No definition available.
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- Details
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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. 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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- Definition
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences not separately disclosed. 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 other deductible tax credit carryforwards not separately disclosed. 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 employee 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 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 loss reserves other than estimated credit losses. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. 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 after valuation allowances. 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 of deferred tax liability attributable to taxable temporary differences not separately disclosed. 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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- Details
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