Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of open agreements to purchase or sell mineral resources, energy, and agricultural products at some future point held at each balance sheet date, that was included in earnings for the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

+ References

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FINANCIAL INSTRUMENTS AND RISK MANAGEMENT (Details) - CAD CAD in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Change in fair value
Total Gain/(Loss)	CAD (169,336)	CAD 242,038	CAD (35,088)
Interest Rate Swaps \| Interest Expenses
Change in fair value
Total Gain/(Loss)			478
Cross currency interest rate swap \| Interest Expenses
Change in fair value
Total Gain/(Loss)		(580)	(1,306)
Cross currency interest rate swap \| Foreign Exchange
Change in fair value
Total Gain/(Loss)		16,128	19,920
Foreign exchange derivatives \| Foreign Exchange
Change in fair value
Total Gain/(Loss)	(21,847)	6,149	8,110
Electricity Swaps \| Operating Expense
Change in fair value
Total Gain/(Loss)	(408)	(1,275)	758
Equity Swaps (gain)/loss \| General and Administrative Expense
Change in fair value
Total Gain/(Loss)	(2,097)	(9,282)	5,450
Commodity Derivative Instruments
Change in fair value
Total Gain/(Loss)	(144,984)	230,898	(68,498)
Commodity Derivative Instruments \| Crude Oil Instruments \| Commodity derivative instruments
Change in fair value
Total Gain/(Loss)	(99,790)	182,019	(65,504)
Commodity Derivative Instruments \| Gas \| Commodity derivative instruments
Change in fair value
Total Gain/(Loss)	CAD (45,194)	CAD 48,879	CAD (2,994)