Represents the percentage of debt based on fixed interest rates.

No definition available.

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- Definition

Represents the percentage of debt based on floating interest rates.

+ References

No definition available.

+ Details

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- Definition

The amount of foreign currency that the entity has contractually agreed, or for which it has the option, to buy or sell with respect to the contract being described.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

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Balance Type:	na
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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

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-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of the required periodic payments applied to principal.

+ 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 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Average contractual rate at which a foreign currency can be purchased or sold.

+ References

No definition available.

+ Details

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Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Nominal or face amount used to calculate payments on the derivative liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Notional Amount
-URI http://asc.fasb.org/extlink&oid=6519104

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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5579245-113959

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Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6450222&loc=d3e30840-110895

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=6450189&loc=d3e30690-110894

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6450189&loc=d3e30700-110894

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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- Details

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FINANCIAL INSTRUMENTS AND RISK MANAGEMENT - Foreign Exchange (Details) CAD in Thousands, $ in Thousands				1 Months Ended	12 Months Ended
	Oct. 01, 2015 CAD	Jun. 19, 2014 USD ($)	Jun. 19, 2014 CAD	Oct. 31, 2015 CAD	Dec. 31, 2015 CAD	Dec. 31, 2014 CAD	Dec. 31, 2013 CAD	Dec. 31, 2015 USD ($)	Oct. 31, 2015 USD ($)	Oct. 01, 2015 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2007 USD ($)
Risk Management
Foreign exchange (gain)/loss \| CAD					CAD (8,705)	CAD 11,165	CAD 17,596
Foreign exchange rate (US$/CDN$)								1.3840
Percentage of debt based on fixed interest rates								93.00%
Percentage of debt based on floating interest rates								7.00%
6.62% senior notes maturing June 19, 2014
Risk Management
Face value of debt		$ 175,000
5.46% senior notes maturing October 1, 2015
Risk Management
Face value of debt									$ 54,000
7.97% senior notes maturing June 18, 2021
Risk Management
Face value of debt								$ 225,000
Foreign exchange derivatives
Risk Management
Foreign exchange (gain)/loss \| CAD					39,200	CAD (700)
Foreign exchange derivatives \| 5.46% senior notes maturing October 1, 2015
Risk Management
Face value of debt										$ 54,000
Foreign exchange (gain)/loss \| CAD	CAD (3,300)			CAD (3,300)
Market Risk \| Cross currency interest rate swap \| 6.62% senior notes maturing June 19, 2014
Risk Management
Face value of debt		175,000
Final principal repayment		$ 35,000
Foreign exchange (gain)/loss \| CAD			CAD 15,800
Market Risk \| Foreign exchange derivatives
Risk Management
Notional debt									$ 10,800
Foreign exchange forward contract amount								$ 6,000
Foreign exchange rate (US$/CDN$)								1.20				1.02
Market Risk \| Foreign exchange derivatives \| 6.62% senior notes maturing June 19, 2014
Risk Management
Face value of debt											$ 175,000
Market Risk \| Foreign exchange derivatives \| 5.46% senior notes maturing October 1, 2015
Risk Management
Face value of debt												$ 54,000
Market Risk \| Foreign exchange derivatives \| 7.97% senior notes maturing June 18, 2021
Risk Management
Face value of debt											$ 225,000
Foreign exchange (gain)/loss \| CAD					CAD (39,900)