Related Party Disclosures (Details) - CAD CAD in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
RELATED PARTY DISCLOSURES
Sales	CAD 590	CAD 667
Purchases	223	152
Accounts receivable	44	61
Accounts payable and accrued liabilities	28	42
Compensation of Key Management Personnel
Salaries and other short-term benefits	12	13
Pension and other post-retirement benefits	5	5
Share-based compensation	49	74
Total	66	92
Parachem Chemicals Inc
RELATED PARTY DISCLOSURES
Sales	301	219
UPI Inc
RELATED PARTY DISCLOSURES
Sales	CAD 0	CAD 226

The amounts payable resulting from related party transactions. [Refer: Related parties [member]]

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The amount of compensation to key management personnel. [Refer: Key management personnel of entity or parent [member]]

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The amount of compensation to key management personnel in the form of post-employment benefits. [Refer: Key management personnel of entity or parent [member]]

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The amount of compensation to key management personnel in the form of share-based payments. [Refer: Key management personnel of entity or parent [member]]

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The amount of compensation to key management personnel in the form of short-term employee benefits. [Refer: Key management personnel of entity or parent [member]]

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The amount of goods purchased by the entity in related party transactions. [Refer: Related parties [member]]

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The amount of revenue arising from the sale of goods in related party transactions. [Refer: Revenue; Related parties [member]]

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