The tax effects of temporary differences between the carrying amounts of assets and liabilities for accounting purposes and the amounts used for tax purposes are presented below:
| As at December 31, | 2017 | 2016 | ||||||
| Deferred tax assets | ||||||||
| Foreign tax credits | $ | 8,639 | $ | 11,447 | ||||
| Minimum tax credits | — | 1,462 | ||||||
| Financing charges | 17,013 | 9,349 | ||||||
| Deferred revenue | 1,879 | — | ||||||
| Loss carry forwards | 52,911 | 23,873 | ||||||
| Employee benefits | 10,430 | 10,084 | ||||||
| Other | 13 | 250 | ||||||
| Total deferred tax assets | $ | 90,885 | $ | 56,465 | ||||
| Deferred tax liabilities | ||||||||
| Capital assets | $ | (244,569 | ) | $ | (271,442 | ) | ||
| Intangibles | (241,731 | ) | (238,908 | ) | ||||
| Finance charges | (17,889 | ) | (9,943 | ) | ||||
| Unrealized foreign exchange gains | (27,193 | ) | (2,327 | ) | ||||
| Deferred revenue | — | (2,234 | ) | |||||
| Total deferred tax liabilities | $ | (531,382 | ) | $ | (524,854 | ) | ||
| Deferred tax liabilities, net | $ | (440,497 | ) | $ | (468,389 | ) | ||