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Assets held for sale (Details) - CAD CAD in Thousands | 12 Months Ended
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Dec. 31, 2016 | Dec. 31, 2015
Property, Plant and Equipment [Line Items] |  |
Gain (loss) on disposal of assets held for sale | CAD 374 | CAD 152
Heavy equipment |  |
Property, Plant and Equipment [Line Items] |  |
Gain (loss) on disposal of assets held for sale | 374 | 152
Heavy equipment | Depreciation expense |  |
Property, Plant and Equipment [Line Items] |  |
Impairment of equipment assets held for sale | CAD 1,556 | CAD 1,384

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- Definition Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=64827811&loc=d3e1361-107760 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=64862545&loc=d3e2941-110230 + Details
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- 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 360 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2611-110228 Reference 2: 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=66902209&loc=d3e3602-108585 + Details
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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
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- Details
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