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Other long term obligations (Tables) | 12 Months Ended
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Dec. 31, 2017
Other Liabilities Disclosure [Abstract] |
Schedule of other long term obligations | Other long term obligations are as follows:
|  | December 31, 2017 |  |  | December 31, 2016 |
Deferred lease inducements liability (note 16(b)) |  | $ | 10 |  |  | $ | 38 |
Asset retirement obligation (note 16(c)) |  | 744 |  |  | 678 |
Directors' deferred stock unit plan (note 21(e)) |  | 5,672 |  |  | 4,945 |
Deferred gain on sale-leaseback (note 16(d)) |  | 7,654 |  |  | 3,199 |
|  | $ | 14,080 |  |  | $ | 8,860 |
Less current portion of: |  |  |  |
Deferred gain on sale-leaseback (note 16(d)) |  | (1,445 | ) |  | (586 | )
|  | $ | 12,635 |  |  | $ | 8,274 |
Schedule of changes in deferred lease inducements |
|  | December 31, 2017 |  |  | December 31, 2016 |
Balance, beginning of year |  | $ | 38 |  |  | $ | 145 |
Amortization of deferred lease inducements |  | (28 | ) |  | (107 | )
Balance, end of year |  | $ | 10 |  |  | $ | 38 |
Schedule of changes in asset retirement obligation | The following table presents a continuity of the liability for the asset retirement obligation:
|  | December 31, 2017 |  |  | December 31, 2016 |
Balance, beginning of year |  | $ | 678 |  |  | $ | 617 |
Accretion expense |  | 66 |  |  | 61 |
Balance, end of year |  | $ | 744 |  |  | $ | 678 |
Schedule of deferred lease inducement assets |
|  | December 31, 2017 |  |  | December 31, 2016 |
Balance, beginning of year |  | $ | 3,199 |  |  | $ | 780 |
Addition |  | 5,155 |  |  | 2,792 |
Amortization of deferred gain on sale-leaseback |  | (700 | ) |  | (373 | )
Balance, end of year |  | $ | 7,654 |  |  | $ | 3,199 |

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- Definition Tabular disclosure of the changes in carrying amount of a liability for asset retirement obligations, for changes such as new obligations, changes in estimates of existing obligations, spending on existing obligations, property dispositions, and foreign currency translation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13201-110859 + Details
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