XML 27 R78.htm IDEA: XBRL DOCUMENT v2.4.1.9

Other long term obligations (Details) (CAD) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Other Liabilities, Noncurrent [Abstract]
Deferred lease inducements	252noa_LeaseIncentivePayableNoncurrent	359noa_LeaseIncentivePayableNoncurrent
Asset retirement obligation	562us-gaap_AssetRetirementObligation	512us-gaap_AssetRetirementObligation
Deferred gain on sale leaseback (note 16(d))	371us-gaap_SaleLeasebackTransactionDeferredGainNet	0us-gaap_SaleLeasebackTransactionDeferredGainNet
Other obligations, current and noncurrent	4,991us-gaap_OtherLiabilities	9,140us-gaap_OtherLiabilities
Less current portion of:
Deferred gain on sale leaseback	(93)noa_SaleLeasebackTransactionDeferredGainCurrent	0noa_SaleLeasebackTransactionDeferredGainCurrent
Other obligations, noncurrent portion	3,459us-gaap_OtherLiabilitiesNoncurrent	7,207us-gaap_OtherLiabilitiesNoncurrent
Lease Incentive, Payable [Roll Forward]
Balance, beginning of year	359us-gaap_LeaseIncentivePayableCurrentAndNoncurrent	466us-gaap_LeaseIncentivePayableCurrentAndNoncurrent
Amortization of deferred lease inducements	(107)us-gaap_AmortizationOfLeaseIncentives	(107)us-gaap_AmortizationOfLeaseIncentives
Balance, end of year	252us-gaap_LeaseIncentivePayableCurrentAndNoncurrent	359us-gaap_LeaseIncentivePayableCurrentAndNoncurrent
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance, beginning of year	512us-gaap_AssetRetirementObligation	466us-gaap_AssetRetirementObligation
Accretion expense	50us-gaap_AssetRetirementObligationAccretionExpense	46us-gaap_AssetRetirementObligationAccretionExpense
Balance, end of year	562us-gaap_AssetRetirementObligation	512us-gaap_AssetRetirementObligation
Estimated undiscounted cash flows required to settle obligation	1,084noa_AssetRetirementObligationEstimatedUndiscountedFutureCashFlowToSettle	1,084noa_AssetRetirementObligationEstimatedUndiscountedFutureCashFlowToSettle
Credit adjusted risk-free rate assumed in measuring the asset retirement obligation (percent)	9.42%noa_AssetRetirementObligationRiskFreeRateUsedToMeasure
Deferred Gain on Sale Leaseback [Roll Forward]
Balance, beginning of year	0us-gaap_SaleLeasebackTransactionDeferredGainNet	0us-gaap_SaleLeasebackTransactionDeferredGainNet
Addition	371noa_SaleLeasebackTransactionDeferredGainAdditions	0noa_SaleLeasebackTransactionDeferredGainAdditions
Balance, end of year	371us-gaap_SaleLeasebackTransactionDeferredGainNet	0us-gaap_SaleLeasebackTransactionDeferredGainNet
Stock options | Senior executive stock option plan
Other Liabilities, Noncurrent [Abstract]
Deferred compensation plans	22us-gaap_DeferredCompensationSharebasedArrangementsLiabilityCurrentAndNoncurrent / us-gaap_AwardTypeAxis = us-gaap_EmployeeStockOptionMember / us-gaap_PlanNameAxis = noa_SeniorExecutiveStockOptionPlanMember	940us-gaap_DeferredCompensationSharebasedArrangementsLiabilityCurrentAndNoncurrent / us-gaap_AwardTypeAxis = us-gaap_EmployeeStockOptionMember / us-gaap_PlanNameAxis = noa_SeniorExecutiveStockOptionPlanMember
Less current portion of:
Deferred compensation plans, current	(22)us-gaap_DeferredCompensationShareBasedArrangementsLiabilityCurrent / us-gaap_AwardTypeAxis = us-gaap_EmployeeStockOptionMember / us-gaap_PlanNameAxis = noa_SeniorExecutiveStockOptionPlanMember	0us-gaap_DeferredCompensationShareBasedArrangementsLiabilityCurrent / us-gaap_AwardTypeAxis = us-gaap_EmployeeStockOptionMember / us-gaap_PlanNameAxis = noa_SeniorExecutiveStockOptionPlanMember
Restricted share units (RSUs) | Restricted share unit plan
Other Liabilities, Noncurrent [Abstract]
Deferred compensation plans	1,779us-gaap_DeferredCompensationSharebasedArrangementsLiabilityCurrentAndNoncurrent / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember / us-gaap_PlanNameAxis = noa_RestrictedShareUnitPlanMember	3,667us-gaap_DeferredCompensationSharebasedArrangementsLiabilityCurrentAndNoncurrent / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember / us-gaap_PlanNameAxis = noa_RestrictedShareUnitPlanMember
Less current portion of:
Deferred compensation plans, current	(1,009)us-gaap_DeferredCompensationShareBasedArrangementsLiabilityCurrent / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember / us-gaap_PlanNameAxis = noa_RestrictedShareUnitPlanMember	(1,933)us-gaap_DeferredCompensationShareBasedArrangementsLiabilityCurrent / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember / us-gaap_PlanNameAxis = noa_RestrictedShareUnitPlanMember
Deferred stock units (DSUs) | Directors' deferred share unit plan
Other Liabilities, Noncurrent [Abstract]
Deferred compensation plans	2,005us-gaap_DeferredCompensationSharebasedArrangementsLiabilityCurrentAndNoncurrent / us-gaap_AwardTypeAxis = noa_DeferredStockUnitsMember / us-gaap_PlanNameAxis = noa_DirectorsDeferredShareUnitPlanMember	3,662us-gaap_DeferredCompensationSharebasedArrangementsLiabilityCurrentAndNoncurrent / us-gaap_AwardTypeAxis = noa_DeferredStockUnitsMember / us-gaap_PlanNameAxis = noa_DirectorsDeferredShareUnitPlanMember
Less current portion of:
Deferred compensation plans, current	(408)us-gaap_DeferredCompensationShareBasedArrangementsLiabilityCurrent / us-gaap_AwardTypeAxis = noa_DeferredStockUnitsMember / us-gaap_PlanNameAxis = noa_DirectorsDeferredShareUnitPlanMember	0us-gaap_DeferredCompensationShareBasedArrangementsLiabilityCurrent / us-gaap_AwardTypeAxis = noa_DeferredStockUnitsMember / us-gaap_PlanNameAxis = noa_DirectorsDeferredShareUnitPlanMember

X

- Definition

Asset Retirement Obligation, Estimated Undiscounted Future Cash Flow to Settle

+ References

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- Definition

Asset Retirement Obligation, Risk-free Rate Used to Measure

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- Definition

Lease Incentive Payable, Noncurrent

+ References

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- Definition

Sale Leaseback Transaction, Deferred Gain, Additions

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Sale Leaseback Transaction, Deferred Gain, Current

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- Definition

Amount of amortization of lease incentive costs incurred by the lessor for the benefit of the lessee.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 25

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=7501430&loc=d3e40010-112707



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-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 25

-Paragraph 7

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 45

-Paragraph 1

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements payable within one year (or the operating cycle, if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.20)

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements.

+ References

No definition available.

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- Definition

This item represents an incentive or inducement contractually stipulated between parties to a lease whereby the lessor has committed to provide the entity (lessee) with a cash payment as inducement to enter the lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

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The aggregate carrying amount, as of the balance sheet date, of liabilities not separately disclosed in the balance sheet.

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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).

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The portion of the gain that will be recorded as income or a reduction in rent expense in future periods less amounts recognized in the current period.

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 40

-Section 35

-Paragraph 1

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