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Capitalized Interest (Tables) | 9 Months Ended
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Sep. 30, 2017
Interest Expense [Abstract] |
Summary of Interest Incurred, Capitalized and Expensed | The following table sets forth details of interest incurred, capitalized and expensed:
|  | Three months ended September 30 |  |  | Nine months ended September 30 |
In thousands |  | 2017 |  |  | 2016 |  |  | 2017 |  |  | 2016 |
Interest cost incurred |  | $ | 5,079 |  |  | $ | 4,334 |  |  | $ | 14,556 |  |  | $ | 12,962 |
Interest capitalized |  |  | 532 |  |  |  | 439 |  |  |  | 1,525 |  |  |  | 998 |
Interest expense |  | $ | 4,547 |  |  | $ | 3,895 |  |  | $ | 13,031 |  |  | $ | 11,964 |

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