v3.3.1.900

Convertible debentures (Details) CAD / shares in Units, $ / shares in Units, shares in Millions, CAD in Millions, $ in Millions						12 Months Ended
	Oct. 31, 2014 CAD	Dec. 11, 2012 CAD CAD / shares	Jul. 05, 2012 USD ($) $ / shares	Oct. 20, 2010 USD ($)	Dec. 17, 2009 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2006 USD ($)	Dec. 31, 2015 CAD shares	Dec. 31, 2014 CAD / shares	Dec. 31, 2013 CAD / shares	Oct. 20, 2010 CAD	Dec. 31, 2009	Dec. 17, 2009 CAD	Dec. 31, 2006 CAD CAD / shares
Movement in convertible debentures
Balance at the beginning of the period						$ 340.6
Foreign exchange gain						(60.3)	$ (38.3)	$ (27.4)
Balance at the end of the period						285.4	340.6
Aggregate interest expenses						17.2	22.8	24.2
Repayment of debt						403.3	639.8	118.8
Amount that may be purchased under the NCIB						$ 28.5
Amount that may be purchased, as a percentage of public float						10.00%
NCIB
Movement in convertible debentures
Repayment of convertible debentures						$ (24.8)
6.5% Debentures due October 2014
Movement in convertible debentures
Balance at the beginning of the period							42.1
Repayment of convertible debentures							(40.6)
Foreign exchange gain							(1.5)
Balance at the end of the period								42.1
Aggregate principal amount of debt | CAD																CAD 60.0
Convertible debentures stated interest rate percentage														6.50%		6.25%
Gross proceeds from issuance of convertible debenture									$ 52.8
Conversion rate of the debentures (in Shares per Dollar)									0.0806452
Conversion price of shares (in dollars per share) | CAD / shares																CAD 12.40
Cumulative amount converted to equity | CAD										CAD 15.2
Cumulative shares issued on conversion | shares										1.2
Repayment of debt | CAD	CAD 44.8
6.25% Debentures due March 2017
Movement in convertible debentures
Balance at the beginning of the period						58.0	63.4
Repayment of convertible debentures						(0.1)
Foreign exchange gain						(9.3)	(5.3)
Gain on repurchase of convertible debentures							(0.1)
Balance at the end of the period						48.6	58.0	$ 63.4
Aggregate principal amount of debt | CAD															CAD 86.3
Convertible debentures stated interest rate percentage															6.25%
Gross proceeds from issuance of convertible debenture					$ 82.1
Conversion rate of the debentures (in Shares per Dollar)								0.0769231
Conversion price of shares (in dollars per share) | CAD / shares												CAD 13.00
Cumulative amount converted to equity | CAD										CAD 18.8
Cumulative shares issued on conversion | shares										1.4
5.6% Debentures due June 2017
Movement in convertible debentures
Balance at the beginning of the period						68.6	75.7
Repayment of convertible debentures						(3.0)	(0.7)
Foreign exchange gain						(10.7)	(6.4)
Gain on repurchase of convertible debentures						(0.1)
Balance at the end of the period						54.8	68.6	$ 75.7
Aggregate principal amount of debt | CAD													CAD 80.5
Convertible debentures stated interest rate percentage													5.60%
Gross proceeds from issuance of convertible debenture				$ 78.9
Conversion rate of the debentures (in Shares per Dollar)								0.0552486
Conversion price of shares (in dollars per share) | CAD / shares											CAD 18.10
5.75% Debentures due June 2019
Movement in convertible debentures
Balance at the beginning of the period						128.3	130.0
Repayment of convertible debentures						(9.4)	(1.3)
Gain on repurchase of convertible debentures						(1.9)	(0.4)
Balance at the end of the period						117.0	128.3	$ 130.0
Aggregate principal amount of debt			$ 130.0
Convertible debentures stated interest rate percentage			5.75%
Conversion rate of the debentures (in Shares per Dollar)			0.057971
Conversion price of shares (in dollars per share) | $ / shares			$ 17.25
Net proceeds from issuance convertible debentures issued, after underwriting discounts and expenses			$ 124.0
6.00% Debenture due December 2019
Movement in convertible debentures
Balance at the beginning of the period						85.7	94.0
Repayment of convertible debentures						(6.4)	(0.4)
Foreign exchange gain						(13.2)	(7.6)
Gain on repurchase of convertible debentures						(1.1)	(0.3)
Balance at the end of the period						65.0	85.7	94.0
Aggregate principal amount of debt | CAD		CAD 100.0
Convertible debentures stated interest rate percentage		6.00%
Conversion rate of the debentures (in Shares per Dollar)		0.0689655
Conversion price of shares (in dollars per share) | CAD / shares		CAD 14.50
Net proceeds from issuance convertible debentures issued, after underwriting discounts and expenses | CAD		CAD 95.5
Convertible Debentures
Movement in convertible debentures
Balance at the beginning of the period						340.6	405.2
Repayment of convertible debentures						(18.9)	(43.0)
Foreign exchange gain						(33.2)	(20.8)
Gain on repurchase of convertible debentures						(3.1)	(0.8)
Balance at the end of the period						$ 285.4	$ 340.6	$ 405.2

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The maximum amount of convertible debentures that may be purchased under the Normal Course Issuer Bid.

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Maximum percentage of public float that may be purchased under Normal Course Issuer Bid for the entity's convertible debentures.

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Cumulative number of shares issued, as of balance sheet date, as a result of the conversion of convertible securities.

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Repayment of debenture instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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