v2.4.0.8

Derivative instruments and hedging activities (Tables) | 9 Months Ended
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Sep. 30, 2013
Derivative instruments and hedging activities |
Schedule of notional volumes of forecasted transactions |
|  | Units |  | September 30, 2013 |  | December 31, 2012 |
--- | --- | --- | --- | --- | --- | --- | ---
Natural gas swaps |  | Natural Gas (Mmbtu) |  |  | 5.6 |  |  | 10.6 |
Gas purchase agreements |  | Natural Gas (GJ) |  |  | 43.9 |  |  | 49.8 |
Interest rate swaps |  | Interest (US$) |  |  | 164.4 |  |  | 172.0 |
Foreign currency forwards |  | Cdn$ |  |  | 34.9 |  |  | 176.6 |
Schedule of fair value of derivative instruments |
|  | September 30, 2013 |
--- | --- | --- | ---
|  | Derivative Assets |  | Derivative Liabilities |
Derivative instruments designated as cash flow hedges: |  |  |  |  |  |  |
Interest rate swaps current |  | $ | — |  | $ | 1.3 |
Interest rate swaps long-term |  |  | — |  |  | 3.2 |
Total derivative instruments designated as cash flow hedges |  |  | — |  |  | 4.5 |
Derivative instruments not designated as cash flow hedges: |  |  |  |  |  |  |
Interest rate swaps current |  |  | — |  |  | 7.5 |
Interest rate swaps long-term |  |  | 7.9 |  |  | 12.6 |
Foreign currency forward contracts current |  |  | 0.6 |  |  | 0.3 |
Foreign currency forward contracts long-term |  |  | 1.6 |  |  | — |
Natural gas swaps current |  |  | — |  |  | 1.2 |
Natural gas swaps long-term |  |  | — |  |  | 3.9 |
Gas purchase agreements current |  |  | — |  |  | 22.8 |
Gas purchase agreements long-term |  |  | — |  |  | 67.4 |
Total derivative instruments not designated as cash flow hedges |  |  | 10.1 |  |  | 115.7 |
Total derivative instruments |  | $ | 10.1 |  | $ | 120.2 |
|  | December 31, 2012 |
--- | --- | --- | ---
|  | Derivative Assets |  | Derivative Liabilities |
Derivative instruments designated as cash flow hedges: |  |  |  |  |  |  |
Interest rate swaps current |  | $ | — |  | $ | 1.3 |
Interest rate swaps long-term |  |  | — |  |  | 5.2 |
Total derivative instruments designated as cash flow hedges |  |  | — |  |  | 6.5 |
Derivative instruments not designated as cash flow hedges: |  |  |  |  |  |  |
Interest rate swaps current |  |  | — |  |  | 7.3 |
Interest rate swaps long-term |  |  | 0.1 |  |  | 27.7 |
Foreign currency forward contracts current |  |  | 9.5 |  |  | — |
Foreign currency forward contracts long-term |  |  | 11.0 |  |  | — |
Natural gas swaps current |  |  | — |  |  | — |
Natural gas swaps long-term |  |  | 0.1 |  |  | 3.9 |
Gas purchase agreements current |  |  | 0.1 |  |  | 24.5 |
Gas purchase agreements long-term |  |  | — |  |  | 81.4 |
Total derivative instruments not designated as cash flow hedges |  |  | 20.8 |  |  | 144.8 |
Total derivative instruments |  | $ | 20.8 |  | $ | 151.3 |
Schedule of changes in OCI attributable to derivative financial instruments |
(in millions) Three months ended September 30, 2013 |  | Interest Rate Swaps |  | Natural Gas Swaps |  | Total |
--- | --- | --- | --- | --- | --- | --- | ---
Accumulated OCI balance at June 30, 2013 |  | $ | (0.4 | ) | $ | — |  | $ | (0.4 | )
Change in fair value of cash flow hedges |  |  | (0.1 | ) |  | — |  |  | (0.1 | )
Realized from OCI during the period |  |  | 0.2 |  |  | — |  |  | 0.2 |
Accumulated OCI balance at September 30, 2013 |  | $ | (0.3 | ) | $ | — |  | $ | (0.3 | )
(in millions) Three months ended September 30, 2012 |  | Interest Rate Swaps |  | Natural Gas Swaps |  | Total |
--- | --- | --- | --- | --- | --- | --- | ---
Accumulated OCI balance at June 30, 2012 |  | $ | (1.7 | ) | $ | 0.2 |  | $ | (1.5 | )
Change in fair value of cash flow hedges |  |  | (0.3 | ) |  | — |  |  | (0.3 | )
Realized from OCI during the period |  |  | 0.2 |  |  | (0.1 | ) |  | 0.1 |
Accumulated OCI balance at September 30, 2012 |  | $ | (1.8 | ) | $ | 0.1 |  | $ | (1.7 | )
(in millions) Nine months ended September 30, 2013 |  | Interest Rate Swaps |  | Natural Gas Swaps |  | Total |
--- | --- | --- | --- | --- | --- | --- | ---
Accumulated OCI balance at December 31, 2012 |  | $ | (1.5 | ) | $ | 0.1 |  | $ | (1.4 | )
Change in fair value of cash flow hedges |  |  | 0.5 |  |  | — |  |  | 0.5 |
Realized from OCI during the period |  |  | 0.7 |  |  | (0.1 | ) |  | 0.6 |
Accumulated OCI balance at September 30, 2013 |  | $ | (0.3 | ) | $ | — |  | $ | (0.3 | )
(in millions) Nine months ended September 30, 2012 |  | Interest Rate Swaps |  | Natural Gas Swaps |  | Total |
--- | --- | --- | --- | --- | --- | --- | ---
Accumulated OCI balance at December 31, 2011 |  | $ | (1.7 | ) | $ | 0.3 |  | $ | (1.4 | )
Change in fair value of cash flow hedges |  |  | (0.8 | ) |  | — |  |  | (0.8 | )
Realized from OCI during the period |  |  | 0.7 |  |  | (0.2 | ) |  | 0.5 |
Accumulated OCI balance at September 30, 2012 |  | $ | (1.8 | ) | $ | 0.1 |  | $ | (1.7 | )
Summary of realized (gains) and losses for derivative instruments not designated as cash flow hedges |
|  |  |  | Three months ended September 30, |
--- | --- | --- | --- | --- | ---
|  | Classification of (gain) loss recognized in income |
|  | 2013 |  | 2012 |
Gas purchase agreements |  | Fuel |  | $ | 7.6 |  | $ | 13.3 |
Foreign currency forwards |  | Foreign exchange gain |  |  | (1.1 | ) |  | (2.1 | )
Interest rate swaps |  | Interest, net |  |  | 2.7 |  |  | 1.2 |
|  |  |  | Nine months ended September 30, |
--- | --- | --- | --- | --- | ---
|  | Classification of (gain) loss recognized in income |
|  | 2013 |  | 2012 |
Gas purchase agreements |  | Fuel |  | $ | 38.0 |  | $ | 29.3 |
Foreign currency forwards |  | Foreign exchange gain |  |  | (14.4 | ) |  | (17.3 | )
Interest rate swaps |  | Interest, net |  |  | 9.4 |  |  | 3.4 |
Summary of the unrealized gains and losses resulting from changes in the fair value of derivative financial instruments that are not designated as cash flow hedges |
|  |  |  | Three months ended September 30, |
--- | --- | --- | --- | --- | ---
|  | Classification of (gain) loss recognized in income |
|  | 2013 |  | 2012 |
Natural gas swaps |  | Change in fair value of derivatives |  | $ | 0.6 |  | $ | (1.0 | )
Gas purchase agreements |  | Change in fair value of derivatives |  |  | 3.6 |  |  | (10.0 | )
Interest rate swaps |  | Change in fair value of derivatives |  |  | (0.7 | ) |  | 0.3 |
Total change in fair value of derivative instruments |  |  |  | $ | 3.5 |  | $ | (10.7 | )
Foreign currency forwards |  | Foreign exchange loss (gain) |  | $ | (0.2 | ) | $ | (4.7 | )
|  |  |  | Nine months ended September 30, |
--- | --- | --- | --- | --- | ---
|  | Classification of (gain) loss recognized in income |
|  | 2013 |  | 2012 |
Natural gas swaps |  | Change in fair value of derivatives |  | $ | 1.4 |  | $ | (0.2 | )
Gas purchase agreements |  | Change in fair value of derivatives |  |  | (12.0 | ) |  | (49.3 | )
Interest rate swaps |  | Change in fair value of derivatives |  |  | (22.8 | ) |  | (1.8 | )
Total change in fair value of derivative instruments |  |  |  | $ | (33.4 | ) | $ | (51.3 | )
Foreign currency forwards |  | Foreign exchange loss (gain) |  | $ | 18.5 |  | $ | 8.2 |

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- Definition Tabular disclosure for realized gains and losses on derivative instruments not designated as hedging instruments of (a) the location and amount of gains and losses reported in the statement of financial performance and (b) the location and fair value amounts of the instruments reported in the statement of financial position. + References No definition available. + Details
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- Definition Tabular disclosure for unrealized gains and losses on derivative instruments not designated as hedging instruments of (a) the location and amount of gains and losses reported in the statement of financial performance and (b) the location and fair value amounts of the instruments reported in the statement of financial position. + References No definition available. + Details
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- Definition Tabular disclosure of the effective portion of the gains and losses on derivative instruments designated (and non-derivative instruments) designated and qualifying in cash flow hedges and net investment hedges that was recognized in other comprehensive income (loss) during the current period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959 + Details
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- Definition Tabular disclosure of the location and fair value amounts of derivative instruments (and nonderivative instruments that are designated and qualify as hedging instruments) reported in the statement of financial position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959 + Details
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- Definition Tabular disclosure of the notional amounts of outstanding derivative positions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959 + Details
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