XML 101 R63.htm IDEA: XBRL DOCUMENT v2.4.1.9

Plant and equipment (Details) (CAD) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Cost	434,435us-gaap_PropertyPlantAndEquipmentGross	466,971us-gaap_PropertyPlantAndEquipmentGross
Accumulated Deprecation	173,537us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	188,996us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
Net Book Value	260,898us-gaap_PropertyPlantAndEquipmentNet	277,975us-gaap_PropertyPlantAndEquipmentNet
Addition of plant and equipment by means of capital leases	39,492us-gaap_CapitalLeaseObligationsIncurred	13,812us-gaap_CapitalLeaseObligationsIncurred
Heavy equipment
Property, Plant and Equipment [Line Items]
Cost	142,052us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_EquipmentMember	251,872us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_EquipmentMember
Accumulated Deprecation	42,292us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_EquipmentMember	96,038us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_EquipmentMember
Net Book Value	99,760us-gaap_PropertyPlantAndEquipmentNet / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_EquipmentMember	155,834us-gaap_PropertyPlantAndEquipmentNet / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_EquipmentMember
Major component parts in use
Property, Plant and Equipment [Line Items]
Cost	112,645us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = noa_MajorComponentPartsInUseMember	60,484us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = noa_MajorComponentPartsInUseMember
Accumulated Deprecation	55,895us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / us-gaap_PropertyPlantAndEquipmentByTypeAxis = noa_MajorComponentPartsInUseMember	23,472us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / us-gaap_PropertyPlantAndEquipmentByTypeAxis = noa_MajorComponentPartsInUseMember
Net Book Value	56,750us-gaap_PropertyPlantAndEquipmentNet / us-gaap_PropertyPlantAndEquipmentByTypeAxis = noa_MajorComponentPartsInUseMember	37,012us-gaap_PropertyPlantAndEquipmentNet / us-gaap_PropertyPlantAndEquipmentByTypeAxis = noa_MajorComponentPartsInUseMember
Other equipment
Property, Plant and Equipment [Line Items]
Cost	41,739us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_OtherMachineryAndEquipmentMember	27,594us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_OtherMachineryAndEquipmentMember
Accumulated Deprecation	18,758us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_OtherMachineryAndEquipmentMember	11,511us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_OtherMachineryAndEquipmentMember
Net Book Value	22,981us-gaap_PropertyPlantAndEquipmentNet / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_OtherMachineryAndEquipmentMember	16,083us-gaap_PropertyPlantAndEquipmentNet / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_OtherMachineryAndEquipmentMember
Licensed motor vehicles
Property, Plant and Equipment [Line Items]
Cost	24,247us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_VehiclesMember	25,911us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_VehiclesMember
Accumulated Deprecation	20,763us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_VehiclesMember	22,474us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_VehiclesMember
Net Book Value	3,484us-gaap_PropertyPlantAndEquipmentNet / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_VehiclesMember	3,437us-gaap_PropertyPlantAndEquipmentNet / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_VehiclesMember
Office and computer equipment
Property, Plant and Equipment [Line Items]
Cost	9,355us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = noa_OfficeAndComputerEquipmentMember	13,846us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = noa_OfficeAndComputerEquipmentMember
Accumulated Deprecation	8,216us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / us-gaap_PropertyPlantAndEquipmentByTypeAxis = noa_OfficeAndComputerEquipmentMember	11,882us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / us-gaap_PropertyPlantAndEquipmentByTypeAxis = noa_OfficeAndComputerEquipmentMember
Net Book Value	1,139us-gaap_PropertyPlantAndEquipmentNet / us-gaap_PropertyPlantAndEquipmentByTypeAxis = noa_OfficeAndComputerEquipmentMember	1,964us-gaap_PropertyPlantAndEquipmentNet / us-gaap_PropertyPlantAndEquipmentByTypeAxis = noa_OfficeAndComputerEquipmentMember
Buildings
Property, Plant and Equipment [Line Items]
Cost	2,791us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_BuildingMember	4,691us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_BuildingMember
Accumulated Deprecation	2,606us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_BuildingMember	2,650us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_BuildingMember
Net Book Value	185us-gaap_PropertyPlantAndEquipmentNet / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_BuildingMember	2,041us-gaap_PropertyPlantAndEquipmentNet / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_BuildingMember
Leasehold improvements
Property, Plant and Equipment [Line Items]
Cost		9,946us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_LeaseholdImprovementsMember
Accumulated Deprecation		6,187us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_LeaseholdImprovementsMember
Net Book Value		3,759us-gaap_PropertyPlantAndEquipmentNet / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_LeaseholdImprovementsMember
Assets under capital lease
Property, Plant and Equipment [Line Items]
Cost	101,606us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_AssetsHeldUnderCapitalLeasesMember	72,627us-gaap_PropertyPlantAndEquipmentGross / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_AssetsHeldUnderCapitalLeasesMember
Accumulated Deprecation	25,007us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_AssetsHeldUnderCapitalLeasesMember	14,782us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_AssetsHeldUnderCapitalLeasesMember
Net Book Value	76,599us-gaap_PropertyPlantAndEquipmentNet / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_AssetsHeldUnderCapitalLeasesMember	57,845us-gaap_PropertyPlantAndEquipmentNet / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_AssetsHeldUnderCapitalLeasesMember
Depreciation expense	12,108us-gaap_Depreciation / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_AssetsHeldUnderCapitalLeasesMember	6,694us-gaap_Depreciation / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_AssetsHeldUnderCapitalLeasesMember

X

- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

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The increase during the period in capital lease obligations due to entering into new capital leases.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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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.

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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.

+ References

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