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v2.4.1.9

Income taxes (Details) (CAD) In Thousands, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2014 provincial_jurisdiction | Dec. 31, 2013
Operating Loss Carryforwards [Line Items] |  |
Loss before income taxes | (728)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest | (24,149)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
Tax rate | 25.26%us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate | 25.26%us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate
Expected benefit | (184)us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate | (6,101)us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate
(Decrease) increase related to: |  |
Impact of enacted future statutory income tax rates | 0 noa_IncomeTaxReconciliationIncomeTaxAdjustmentsAndReassessments | (209)noa_IncomeTaxReconciliationIncomeTaxAdjustmentsAndReassessments
Income tax adjustments and reassessments | (68)us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance | (249)us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance
Non deductible portion of capital losses | (72)noa_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseNondeductiblePortionofCapitalLossesAmount | 69 noa_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseNondeductiblePortionofCapitalLossesAmount
Stock-based compensation | 232 us-gaap_IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost | 315 us-gaap_IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost
Other | 61 us-gaap_IncomeTaxReconciliationOtherAdjustments | 73 us-gaap_IncomeTaxReconciliationOtherAdjustments
Income tax benefit | (31)us-gaap_IncomeTaxExpenseBenefit | (6,102)us-gaap_IncomeTaxExpenseBenefit
Current income tax (benefit) expense | (92)us-gaap_CurrentIncomeTaxExpenseBenefit | (2,438)us-gaap_CurrentIncomeTaxExpenseBenefit
Deferred income tax benefit | 61 us-gaap_DeferredIncomeTaxExpenseBenefit | (3,664)us-gaap_DeferredIncomeTaxExpenseBenefit
Deferred tax assets: |  |
Non-capital losses | 31,151 us-gaap_DeferredTaxAssetsOperatingLossCarryforwards | 39,604 us-gaap_DeferredTaxAssetsOperatingLossCarryforwards
Deferred financing costs | 1,135 noa_DeferredTaxAssetsDeferredFinancingCosts | 1,709 noa_DeferredTaxAssetsDeferredFinancingCosts
Billings in excess of costs on uncompleted contracts | 0 noa_DeferredTaxAssetsBillingsInExcessOfCosts | 1,606 noa_DeferredTaxAssetsBillingsInExcessOfCosts
Capital lease obligations | 16,148 noa_DeferredTaxAssetsCapitalLeaseObligations | 10,914 noa_DeferredTaxAssetsCapitalLeaseObligations
Deferred lease inducements | 64 noa_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsDeferredLeaseIncentives | 91 noa_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsDeferredLeaseIncentives
Stock-based compensation | 1,666 us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost | 1,880 us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost
Other | 481 us-gaap_DeferredTaxAssetsOther | 409 us-gaap_DeferredTaxAssetsOther
Total deferred tax assets | 50,645 us-gaap_DeferredTaxAssetsGross | 56,213 us-gaap_DeferredTaxAssetsGross
Deferred tax liabilities: |  |
Unbilled revenue and uncertified revenue included in accounts receivable | 9,538 noa_DeferredTaxLiabilitiesUnbilledRevenueAndUncertifiedRevenueIncludedInAccountsReceivable | 5,338 noa_DeferredTaxLiabilitiesUnbilledRevenueAndUncertifiedRevenueIncludedInAccountsReceivable
Assets held for sale | 6,466 noa_DeferredTaxLiabilitiesAssetsHeldForSale | 13 noa_DeferredTaxLiabilitiesAssetsHeldForSale
Accounts receivable – holdbacks | 3,084 noa_DeferredTaxLiabilitiesAccountsReceivableHoldbacks | 2,308 noa_DeferredTaxLiabilitiesAccountsReceivableHoldbacks
Property, plant and equipment | 58,134 us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment | 56,945 us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment
Deferred partnership income | 0 us-gaap_DeferredTaxLiabilitiesOther | 18,125 us-gaap_DeferredTaxLiabilitiesOther
Total deferred tax liabilities | 77,222 us-gaap_DeferredIncomeTaxLiabilities | 82,729 us-gaap_DeferredIncomeTaxLiabilities
Net deferred income tax liability | (26,577)us-gaap_DeferredTaxAssetsLiabilitiesNet | (26,516)us-gaap_DeferredTaxAssetsLiabilitiesNet
Net deferred tax liability classification |  |
Current asset | 5,609 us-gaap_DeferredTaxAssetsNetCurrent | 3,678 us-gaap_DeferredTaxAssetsNetCurrent
Long term asset | 29,947 us-gaap_DeferredTaxAssetsNetNoncurrent | 27,660 us-gaap_DeferredTaxAssetsNetNoncurrent
Current liability | (20,056)us-gaap_DeferredTaxLiabilitiesGrossCurrent | (8,036)us-gaap_DeferredTaxLiabilitiesGrossCurrent
Long term liability | (42,077)us-gaap_DeferredTaxLiabilitiesGrossNoncurrent | (49,818)us-gaap_DeferredTaxLiabilitiesGrossNoncurrent
Net deferred income tax liability | (26,577)us-gaap_DeferredTaxAssetsLiabilitiesNet | (26,516)us-gaap_DeferredTaxAssetsLiabilitiesNet
Number of provincial jurisdictions | 3 noa_NumberOfProvincialIncomeTaxingJurisdictions |
Number of Additional Provincial Income Taxing Jurisdictions, Prior to Disposal | 2 noa_NumberofAdditionalProvincialIncomeTaxingJurisdictionsPriortoDisposal |
Operating loss carryforwards | 123,307 us-gaap_OperatingLossCarryforwards |
2026 |  |
Net deferred tax liability classification |  |
Operating loss carryforwards | 283 us-gaap_OperatingLossCarryforwards / noa_YearOfExpirationAxis = noa_TwoThousandTwentySixMember |
2027 |  |
Net deferred tax liability classification |  |
Operating loss carryforwards | 0 us-gaap_OperatingLossCarryforwards / noa_YearOfExpirationAxis = noa_TwoThousandTwentySevenMember |
2028 |  |
Net deferred tax liability classification |  |
Operating loss carryforwards | 0 us-gaap_OperatingLossCarryforwards / noa_YearOfExpirationAxis = noa_TwoThousandTwentyEightMember |
2029 |  |
Net deferred tax liability classification |  |
Operating loss carryforwards | 1 us-gaap_OperatingLossCarryforwards / noa_YearOfExpirationAxis = noa_TwoThousandTwentyNineMember |
2030 |  |
Net deferred tax liability classification |  |
Operating loss carryforwards | 5,334 us-gaap_OperatingLossCarryforwards / noa_YearOfExpirationAxis = noa_TwoThousandThirtyMember |
2031 |  |
Net deferred tax liability classification |  |
Operating loss carryforwards | 18,567 us-gaap_OperatingLossCarryforwards / noa_YearOfExpirationAxis = noa_TwoThousandThirtyOneMember |
2032 |  |
Net deferred tax liability classification |  |
Operating loss carryforwards | 48,910 us-gaap_OperatingLossCarryforwards / noa_YearOfExpirationAxis = noa_TwoThousandThirtyTwoMember |
2033 |  |
Net deferred tax liability classification |  |
Operating loss carryforwards | 34,788 us-gaap_OperatingLossCarryforwards / noa_YearOfExpirationAxis = noa_TwoThousandThirtyThreeMember |
2034 |  |
Net deferred tax liability classification |  |
Operating loss carryforwards | 15,424 us-gaap_OperatingLossCarryforwards / noa_YearOfExpirationAxis = noa_TwoThousandThirtyFourMember |
Capital loss carryforward |  |
Net deferred tax liability classification |  |
Valuation allowance, amount | 962 us-gaap_DeferredTaxAssetsValuationAllowance / us-gaap_ValuationAllowanceByDeferredTaxAssetAxis = us-gaap_CapitalLossCarryforwardMember | 962 us-gaap_DeferredTaxAssetsValuationAllowance / us-gaap_ValuationAllowanceByDeferredTaxAssetAxis = us-gaap_CapitalLossCarryforwardMember

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