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Contingencies Contingencies (Details) - CAD CAD in Thousands | Dec. 31, 2016 | Dec. 31, 2013
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Contingent receivable on previous sale |  |
Loss Contingencies [Line Items] |  |
Contingent additional proceeds on disposal | CAD 92,500 | CAD 92,500

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- Definition Disposal Group, Including Discontinued Operation, Contingent Consideration, Maximum Proceeds + References No definition available. + Details
Name: | noa_DisposalGroupIncludingDiscontinuedOperationContingentConsiderationMaximumProceeds
Namespace Prefix: | noa_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_LossContingenciesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Details
Name: | us-gaap_LossContingenciesByNatureOfContingencyAxis=noa_ContingentGainonSaleofBusinessMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |