v2.4.0.6

Income taxes (Tables) | 12 Months Ended
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Dec. 31, 2012
Income taxes |
Schedule of components of income tax expenses (benefit) |
|  | 2012 |  | 2011 |  | 2010 |
--- | --- | --- | --- | --- | --- | --- | ---
Current income tax expense (benefit) |  | $ | 7,773 |  | $ | 1,584 |  | $ | 960 |
Deferred tax expense (benefit) |  |  | (35,856 | ) |  | (12,688 | ) |  | 15,058 |
Total income tax expense (benefit) |  | $ | (28,083 | ) | $ | (11,104 | ) | $ | 16,018 |
Schedule of reconciliation of income taxes calculated at the Canadian enacted statutory rate to the provision for income taxes in the consolidated statements of operations | The following is a reconciliation of income taxes calculated at the Canadian enacted statutory rate of 25.0%, 26.5%, and 28.5% at December 31, 2012, 2011 and 2010, respectively, to the provision for income taxes in the consolidated statements of operations:
|  | 2012 |  | 2011 |  | 2010 |
--- | --- | --- | --- | --- | --- | --- | ---
Computed income tax expense at Canadian statutory rate |  | $ | (36,216 | ) | $ | (21,975 | ) | $ | (3,410 | )
Increases/(decreases) resulting from: |  |  |  |  |  |  |  |  |  |
Operating countries with different income tax rates |  |  | (8,532 | ) |  | (10,553 | ) |  | (1,220 | )
|  |  | (44,748 | ) |  | (32,528 | ) |  | (4,630 | )
Change in valuation allowance |  |  | 20,186 |  |  | 21,669 |  |  | 19,845 |
|  | $ | (24,562 | ) | $ | (10,859 | ) | $ | 15,215 |
Dividend withholding and preferred share taxes |  |  | 5,912 |  |  | 371 |  |  | 765 |
Foreign exchange |  |  | 1,505 |  |  | (113 | ) |  | — |
Permanent differences |  |  | (6,459 | ) |  | (1,479 | ) |  | — |
Non-deductible acquisition costs |  |  | 637 |  |  | 4,287 |  |  | — |
Non-deductible interest expense |  |  | — |  |  | 2,134 |  |  | — |
Changes in tax rates |  |  | 1,805 |  |  | — |  |  | — |
Federal stimulus grant |  |  | — |  |  | (6,573 | ) |  | — |
Change in estimates of tax basis of equity method investments |  |  | (5,142 | ) |  | 2,246 |  |  | — |
Other |  |  | (1,779 | ) |  | (1,118 | ) |  | 38 |
|  |  | (3,521 | ) |  | (245 | ) |  | 803 |
|  | $ | (28,083 | ) | $ | (11,104 | ) | $ | 16,018 |
Schedule of significant portions of the deferred tax assets and deferred tax liabilities | The tax effect of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities at December 31, 2012 and 2011 are presented below:
|  | 2012 |  | 2011 |
--- | --- | --- | --- | --- | ---
Deferred tax assets: |  |  |  |  |  |  |
Loss carryforwards |  | $ | 130,149 |  | $ | 122,472 |
Other accrued liabilities |  |  | 10,906 |  |  | 28,059 |
Finance and share issuance costs |  |  | 8,349 |  |  | 6,532 |
Disallowed interest carryforward |  |  | 2,214 |  |  | 9,189 |
Derivative contracts |  |  | 3,481 |  |  | — |
Unrealized foreign exchange loss |  |  | — |  |  | 441 |
Other |  |  | 6,094 |  |  | — |
Total deferred tax assets |  |  | 161,193 |  |  | 166,693 |
Valuations allowance |  |  | (116,002 | ) |  | (89,020 | )
|  |  | 45,191 |  |  | 77,673 |
Deferred tax liabilities: |  |  |  |  |  |  |
Intangible assets |  |  | (113,277 | ) |  | (121,055 | )
Property, plant and equipment |  |  | (94,660 | ) |  | (133,689 | )
Derivative contracts |  |  | — |  |  | (4,752 | )
Other long-term investments |  |  | (1,272 | ) |  | (921 | )
Other |  |  | — |  |  | (181 | )
Total deferred tax liabilities |  |  | (209,209 | ) |  | (260,598 | )
Net deferred tax liability |  | $ | (164,018 | ) | $ | (182,925 | )
Summary of the net deferred tax position | The following table summarizes the net deferred tax position as of December 31, 2012 and 2011:
|  | 2012 |  | 2011 |
--- | --- | --- | --- | --- | ---
Long-term deferred tax liabilities |  |  | (164,018 | ) |  | (182,925 | )
Net deferred tax asset (liability) |  | $ | (164,018 | ) | $ | (182,925 | )
Schedule of amounts of net operating loss carryforwards and their expiration years | As of December 31, 2012, we had the following net operating loss carryforwards that are scheduled to expire in the following years:
2027 |  |  | 63,565 |
2028 |  |  | 104,436 |
2029 |  |  | 85,277 |
2030 |  |  | 25,805 |
2031 |  |  | 59,265 |
2032 |  |  | 46,053 |
|  | $ | 384,401 |

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- Definition Tabular disclosure of the components of income tax expense attributable to continuing operations for each year presented including, but not limited to: current tax expense (benefit), deferred tax expense (benefit), investment tax credits, government grants, the benefits of operating loss carryforwards, tax expense that results from allocating certain tax benefits either directly to contributed capital or to reduce goodwill or other noncurrent intangible assets of an acquired entity, adjustments of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity, and adjustments of the beginning-of-the-year balances of a valuation allowance because of a change in circumstances that causes a change in judgment about the realizability of the related deferred tax asset in future years. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319 + Details
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- Definition Tabular disclosure of the components of net deferred tax asset or liability recognized in an entity's statement of financial position, including the following: the total of all deferred tax liabilities, the total of all deferred tax assets, the total valuation allowance recognized for deferred tax assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319 + Details
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- Definition Tabular disclosure of the reconciliation using percentage or dollar amounts of the reported amount of income tax expense attributable to continuing operations for the year to the amount of income tax expense that would result from applying domestic federal statutory tax rates to pretax income from continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319 + Details
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