|
Accounting for derivative instruments and hedging activities (Tables)
|
12 Months Ended |
|
Dec. 31, 2012
|
| Accounting for derivative instruments and hedging activities |
|
| Schedule of notional volumes of forecasted transactions |
|
|
|
|
|
|
|
|
|
|
|
|
Units |
|
December 31,
2012 |
|
December 31,
2011 |
|
|
Natural gas swaps |
|
Natural Gas (Mmbtu) |
|
|
10,640 |
|
|
14,140 |
|
|
Gas Purchase Agreements |
|
Natural Gas (GJ) |
|
|
49,810 |
|
|
— |
|
|
Interest Rate Swaps |
|
Interest (US$) |
|
|
140,154 |
|
|
52,711 |
|
|
Currency forwards |
|
Cdn$ |
|
|
176,550 |
|
|
312,533 |
|
|
| Schedule of fair value of derivative instruments |
|
|
|
|
|
|
|
|
|
|
December 31, 2012 |
|
|
|
Derivative
Assets |
|
Derivative
Liabilities |
|
|
Derivative instruments designated as cash flow hedges: |
|
|
|
|
|
|
|
|
Interest rate swaps current |
|
$ |
— |
|
$ |
1,340 |
|
|
Interest rate swaps long-term |
|
|
— |
|
|
5,167 |
|
| |
|
|
|
|
|
|
Total derivative instruments designated as cash flow hedges |
|
|
— |
|
|
6,507 |
|
| |
|
|
|
|
|
|
Derivative instruments not designated as cash flow hedges: |
|
|
|
|
|
|
|
|
Interest rate swaps current |
|
|
— |
|
|
7,261 |
|
|
Interest rate swaps long-term |
|
|
69 |
|
|
27,713 |
|
|
Foreign currency forward contracts current |
|
|
9,456 |
|
|
— |
|
|
Foreign currency forward contracts long-term |
|
|
10,998 |
|
|
— |
|
|
Natural gas swaps current |
|
|
— |
|
|
— |
|
|
Natural gas swaps long-term |
|
|
117 |
|
|
3,864 |
|
|
Gas purchase agreements current |
|
|
71 |
|
|
24,544 |
|
|
Gas purchase agreements long-term |
|
|
— |
|
|
81,359 |
|
| |
|
|
|
|
|
|
Total derivative instruments not designated as cash flow hedges |
|
|
20,711 |
|
|
144,741 |
|
| |
|
|
|
|
|
|
Total derivative instruments |
|
$ |
20,711 |
|
$ |
151,248 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
December 31, 2011 |
|
|
|
Derivative
Assets |
|
Derivative
Liabilities |
|
|
Derivative instruments designated as cash flow hedges: |
|
|
|
|
|
|
|
|
Interest rate swaps current |
|
$ |
— |
|
$ |
1,561 |
|
|
Interest rate swaps long-term |
|
|
— |
|
|
5,317 |
|
| |
|
|
|
|
|
|
Total derivative instruments designated as cash flow hedges |
|
|
— |
|
|
6,878 |
|
| |
|
|
|
|
|
|
Derivative instruments not designated as cash flow hedges: |
|
|
|
|
|
|
|
|
Interest rate swaps current |
|
|
— |
|
|
2,587 |
|
|
Interest rate swaps long-term |
|
|
— |
|
|
9,637 |
|
|
Foreign currency forward contracts current |
|
|
10,630 |
|
|
224 |
|
|
Foreign currency forward contracts long-term |
|
|
22,224 |
|
|
221 |
|
|
Natural gas swaps current |
|
|
— |
|
|
16,439 |
|
|
Natural gas swaps long-term |
|
|
— |
|
|
18,216 |
|
|
Gas purchase agreements current |
|
|
— |
|
|
— |
|
|
Gas purchase agreements long-term |
|
|
— |
|
|
— |
|
| |
|
|
|
|
|
|
Total derivative instruments not designated as cash flow hedges |
|
|
32,854 |
|
|
47,324 |
|
| |
|
|
|
|
|
|
Total derivative instruments |
|
$ |
32,854 |
|
$ |
54,202 |
|
| |
|
|
|
|
|
|
| Schedule of changes in OCI attributable to derivative financial instruments |
|
|
|
|
|
|
|
|
|
|
|
|
For the year ended December 31, 2012 |
|
Interest
Rate
Swaps |
|
Natural
Gas
Swaps |
|
Total |
|
|
Accumulated OCI balance at January 1, 2012 |
|
$ |
(1,704 |
) |
$ |
321 |
|
$ |
(1,383 |
) |
|
Change in fair value of cash flow hedges |
|
|
(949 |
) |
|
— |
|
|
(949 |
) |
|
Realized from OCI during the period |
|
|
1,120 |
|
|
(232 |
) |
|
888 |
|
| |
|
|
|
|
|
|
|
|
Accumulated OCI balance at December 31, 2012 |
|
$ |
(1,533 |
) |
$ |
89 |
|
$ |
(1,444 |
) |
| |
|
|
|
|
|
|
|
|
Gains (losses) expected to be realized from OCI in the next 12 months, net of $593 tax |
|
$ |
979 |
|
$ |
(89 |
) |
$ |
890 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
For the year ended December 31, 2011 |
|
Interest
Rate
Swaps |
|
Natural
Gas
Swaps |
|
Total |
|
|
Accumulated OCI balance at January 1, 2011 |
|
$ |
(427 |
) |
$ |
682 |
|
$ |
255 |
|
|
Change in fair value of cash flow hedges |
|
|
(2,647 |
) |
|
— |
|
|
(2,647 |
) |
|
Realized from OCI during the period |
|
|
1,370 |
|
|
(361 |
) |
|
1,009 |
|
| |
|
|
|
|
|
|
|
|
Accumulated OCI balance at December 31, 2011 |
|
$ |
(1,704 |
) |
$ |
321 |
|
$ |
(1,383 |
) |
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
For the year ended December 31, 2010 |
|
Interest
Rate
Swaps |
|
Natural
Gas
Swaps |
|
Total |
|
|
Accumulated OCI balance at January 1, 2010 |
|
$ |
(538 |
) |
$ |
(321 |
) |
$ |
(859 |
) |
|
Change in fair value of cash flow hedges |
|
|
(360 |
) |
|
— |
|
|
(360 |
) |
|
Realized from OCI during the period |
|
|
471 |
|
|
1,003 |
|
|
1,474 |
|
| |
|
|
|
|
|
|
|
|
Accumulated OCI balance at December 31, 2010 |
|
$ |
(427 |
) |
$ |
682 |
|
$ |
255 |
|
| |
|
|
|
|
|
|
|
|
|
Realized (gains) and losses
|
|
| Gains and losses for derivative instruments |
|
| Schedule of (gains) and losses for derivative instruments not designated as cash flow hedges |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Year ended December 31, |
|
|
|
Classification of (gain) loss
recognized in income |
|
|
|
2012 |
|
2011 |
|
2010 |
|
|
Gas purchase agreements |
|
Fuel |
|
|
43,470 |
|
|
— |
|
|
— |
|
|
Interest rate swaps |
|
Interest, net |
|
|
4,584 |
|
|
4,166 |
|
|
1,664 |
|
|
Foreign currency forwards |
|
Foreign exchange (gain) loss |
|
|
(18,483 |
) |
|
5,201 |
|
|
(6,625 |
) |
|
|
Unrealized gains and losses
|
|
| Gains and losses for derivative instruments |
|
| Schedule of (gains) and losses for derivative instruments not designated as cash flow hedges |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Year ended December 31, |
|
|
|
Classification of (gain) loss
recognized in income |
|
|
|
2012 |
|
2011 |
|
2010 |
|
|
Natural gas swaps |
|
Change in fair value of derivatives |
|
$ |
(1,241 |
) |
$ |
(2,357 |
) |
$ |
(148 |
) |
|
Gas purchase agreements |
|
Change in fair value of derivatives |
|
$ |
(56,954 |
) |
|
— |
|
|
— |
|
|
Interest rate swaps |
|
Change in fair value of derivatives |
|
|
(1,077 |
) |
|
(12,237 |
) |
|
3,423 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
$ |
(59,272 |
) |
$ |
(14,594 |
) |
$ |
3,275 |
|
| |
|
|
|
|
|
|
|
|
|
|
Foreign currency forwards |
|
Foreign exchange (gain) loss |
|
$ |
11,956 |
|
$ |
14,211 |
|
$ |
(3,542 |
) |
| |
|
|
|
|
|
|
|
|
|
|