FINANCIAL INSTRUMENTS AND RISK MANAGEMENT - Fair Value (Details) - CAD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Assets, current
Assets
Assets	$ 10,570	$ 59,258
Liabilities, current
Liabilities
Liabilities	2,734	32,220
Liabilities, long-term
Liabilities
Liabilities		1,909
Equity Swaps \| Liabilities, current
Liabilities
Liabilities	2,217
Equity Swaps \| Liabilities, long-term
Liabilities
Liabilities		1,909
Commodity Derivative Instruments \| Crude oil \| Assets, current
Assets
Assets	10,570	48,314
Commodity Derivative Instruments \| Crude oil \| Liabilities, current
Liabilities
Liabilities	$ 517	32,220
Commodity Derivative Instruments \| Gas \| Assets, current
Assets
Assets		$ 10,944

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=118948506&loc=SL51823488-111719

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (a),(c)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226000-175313

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