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v3.19.1

Debt instruments (Tables) | 12 Months Ended
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Dec. 31, 2018
Disclosure of detailed information about borrowings [abstract] |
Schedule of debt instruments | Debt instruments comprise the following at December 31:
|  | 2018 | 2017
|  | US$'000 | US$'000
Unsecured notes carried at amortised cost |  |  |
Principal amount |  | 350,000 | 350,000
Unamortised issuance costs |  | (8,343) | (10,668)
Accrued coupon interest |  | 10,937 | 10,938
Total |  | 352,594 | 350,270
Amount due for settlement within 12 months |  | 10,937 | 10,938
Amount due for settlement after 12 months |  | 341,657 | 339,332
Total |  | 352,594 | 350,270

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