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Revenue - Contract balances (Details) - CAD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Revenue from Contract with Customer [Abstract] |  |
Contract receivables, included in accounts receivable, net | $ 78,278 | $ 45,716
Contract assets | 10,673 | 21,572
Contract liabilities | 4,032 | 824
Significant Changes in Contract Assets |  |
Transferred to receivables from contract assets recognized at the beginning of the period | (14,701) | (9,129)
Increases as a result of changes to the estimate of the stage of completion, excluding amounts transferred in the period | 2,043 | 6,183
Increases as a result of work completed, but not yet an unconditional right to consideration | 409 | 8,554
Increases as a result of Nuna acquisition | 1,350 | 0
Significant Changes in Contract Liabilities |  |
Revenue recognized that was included in the contract liability balance at the beginning of the period | (84) | (347)
Increases due to cash received, excluding amounts recognized as revenue during the period | 1,379 | 100
Increases as a result of Nuna acquisition | 1,913 | 0
Performance Obligation |  |
Revenue recognized | $ 2,516 | $ 1,177

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- Definition Contract With Customer, Liability, Increase From Cash Receipts + References No definition available. + Details
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- Definition Contract with Customer, Asset, Accounts Receivable, Net, Current + References No definition available. + Details
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- Definition Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from change in measure of progress which increases (decreases) right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130551-203045 + Details
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- Definition Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130531-203044 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130533-203044 + Details
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