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Other long term obligations Other long term obligations - Additional disclosures (Details) - CAD CAD in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2016 | Dec. 31, 2015
Lease Incentive, Payable [Roll Forward] |  |  |  |
Balance, beginning of year | CAD 145 | CAD 252 |  |
Amortization of deferred lease inducements | (107) | (107) |  |
Balance, end of year | 145 | 252 | CAD 38 | CAD 145
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] |  |  |  |
Balance, beginning of year | 617 | 562 |  |
Accretion expense | 61 | 55 |  |
Balance, end of year | CAD 678 | 617 |  |
Estimated undiscounted cash flows required to settle obligation |  |  | CAD 1,084 | CAD 1,084
Credit adjusted risk-free rate assumed in measuring the asset retirement obligation (percent) | 9.42% |  |  |
Deferred Gain on Sale Leaseback [Roll Forward] |  |  |  |
Balance, beginning of year | CAD 780 | 371 |  |
Addition | 2,792 | 512 |  |
Amortization of deferred gain on sale leaseback | (373) | (103) |  |
Balance, end of year | CAD 3,199 | CAD 780 |  |

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- Definition Asset Retirement Obligation, Estimated Undiscounted Future Cash Flow to Settle + References No definition available. + Details
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- Definition Asset Retirement Obligation, Risk-free Rate Used to Measure + References No definition available. + Details
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- Definition Deferred Gain on Sale Leaseback [Roll Forward] + References No definition available. + Details
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- Definition Lease Incentive, Payable [Roll Forward] + References No definition available. + Details
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- Definition Sale Leaseback Transaction, Deferred Gain, Additions + References No definition available. + Details
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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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 25 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=7501430&loc=d3e40019-112707 + Details
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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) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Asset Retirement Obligation -URI http://asc.fasb.org/extlink&oid=6505190 + Details
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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 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)(3) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848 + Details
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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 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.15(a)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.15(5)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition The portion of the deferred gain that was recognized in the current period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 40 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=35688829&loc=d3e50609-112754 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 40 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=35688829&loc=d3e50609-112754 + Details
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