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Assets held for sale (Details) (CAD) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Long Lived Assets Held-for-sale [Line Items]
Loss (gain) on disposal of assets held for sale	2,212	(90)
Heavy equipment
Long Lived Assets Held-for-sale [Line Items]
Loss (gain) on disposal of assets held for sale	2,212	(90)
Depreciation expense | Heavy equipment
Long Lived Assets Held-for-sale [Line Items]
Impairment of assets held for sale	3,097	8,622

X

- Definition

Gain (Loss) on Disposition of Assets Held for Sale

+ References

No definition available.

+ Details

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Namespace Prefix:	noa_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 45

-Paragraph 15

-URI http://asc.fasb.org/extlink&oid=8077374&loc=d3e2611-110228

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Period Type:	duration

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- Details

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