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Long term debt - Credit Facility Narrative (Details) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2017 CAD convenant | Dec. 31, 2016 CAD | Aug. 01, 2017 CAD | Jul. 31, 2017 CAD
Line of Credit Facility [Line Items] |  |  |  |
Payments of financing fees | CAD 2,982,000 | CAD 99,000 |  |
Revolver |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Maximum borrowing capacity of credit facility |  |  | CAD 140,000,000.0 |
Additional borrowing limit |  |  | 25,000,000 |
Capital lease borrowing limit |  |  | CAD 100,000,000.0 |
Amount outstanding during period | 800,000 | 800,000 |  |
Prior borrowings |  |  |  | CAD 70,000,000
Unused borrowing availability under the revolving facility |  | 58,200,000 |  |
Payments of financing fees | 840,000 | 30,000 |  |
Write off of debt issuance costs | CAD 329,000 |  |  |
Term loan |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Prior borrowings |  |  |  | CAD 30,000,000
Number of financial covenants | convenant | 2 |  |  |
Senior leverage ratio | 3.0 |  |  |
Minimum |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Standby fees percentage | 0.35% |  |  |
Minimum | Revolver |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Prior borrowings | CAD 107,200,000 | 51,700,000 |  |
Maximum |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Standby fees percentage | 0.65% |  |  |
Maximum | Revolver |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Prior borrowings |  | CAD 92,100,000 |  |
Maximum | Term loan |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Senior leverage ratio | 3.5 |  |  |
Fixed charge ratio | 1.15 |  |  |

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- Definition Line of Credit Facility, Accordion Feature, Increase Limit + References No definition available. + Details
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- Definition Line of Credit Facility, Capital Lease, Maximum Borrowing Capacity + References No definition available. + Details
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- Definition The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. + References No definition available. + Details
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- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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