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Segmented Information (Schedule of Segmented Information) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Disclosure of operating segments [line items] |  |
Sales to external customers | $ 257,187 | $ 263,296
Cost of sales before depreciation and depletion | (128,248) | (122,252)
Depreciation and depletion in cost of sales | (44,358) | (44,473)
Selling, general and administration | (29,805) | (26,189)
Other income (expenses) | (20,582) | (8,796)
Finance items | 9,777 | 5,754
Income before income taxes | 43,971 | 67,340
Total tax expense | (20,175) | (33,350)
Net income for the year | 23,796 | 33,990
Assets | 936,065 | 786,517
Liabilities | 300,639 | 183,713
Capital Expenditure | 238,637 | 117,407
Material reconciling items [member] |  |
Disclosure of operating segments [line items] |  |
Selling, general and administration | (17,438) | (14,692)
Other income (expenses) | (4,402) | (411)
Finance items | (80) | (1,172)
Income before income taxes | (21,920) | (16,275)
Total tax expense | (511) | (3,168)
Net income for the year | (22,431) | (19,443)
Assets | 60,134 | 31,739
Liabilities | 162,210 | 84,575
Capital Expenditure | 1,333 | 1,448
Bateas Reporting Segment [member] |  |
Disclosure of operating segments [line items] |  |
Sales to external customers | 72,882 | 87,449
Cost of sales before depreciation and depletion | (44,829) | (48,035)
Depreciation and depletion in cost of sales | (13,621) | (12,222)
Selling, general and administration | (4,569) | (3,973)
Other income (expenses) | (664) | (311)
Finance items | (1,552) | 6,263
Income before income taxes | 7,647 | 29,171
Total tax expense | (2,761) | (10,628)
Net income for the year | 4,886 | 18,543
Assets | 116,501 | 174,985
Liabilities | 36,747 | 35,568
Capital Expenditure | 11,845 | 16,400
Cuzcatlan Reporting Segment [member] |  |
Disclosure of operating segments [line items] |  |
Sales to external customers | 184,305 | 175,847
Cost of sales before depreciation and depletion | (83,419) | (74,217)
Depreciation and depletion in cost of sales | (30,737) | (32,251)
Selling, general and administration | (7,798) | (7,524)
Other income (expenses) | (1,928) | (3,938)
Finance items | 385 | 1,111
Income before income taxes | 60,808 | 59,028
Total tax expense | (18,032) | (18,544)
Net income for the year | 42,776 | 40,484
Assets | 252,100 | 286,621
Liabilities | 42,264 | 38,220
Capital Expenditure | 14,046 | 16,224
Mansfield Reporting [Member] |  |
Disclosure of operating segments [line items] |  |
Other income (expenses) | (13,588) | (4,136)
Finance items | 11,024 | (448)
Income before income taxes | (2,564) | (4,584)
Total tax expense | 1,129 | (1,010)
Net income for the year | (1,435) | (5,594)
Assets | 507,330 | 293,172
Liabilities | 59,418 | 25,350
Capital Expenditure | $ 211,413 | $ 83,335

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