XML 364 R102.htm IDEA: XBRL DOCUMENT v3.21.1
Finance Expense - Additional Information (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Statement [line items]      
Borrowing costs [1] $ 13.2 $ 43.4 $ 17.5
Additions to property plant and equipment 0.0 612.5  
General Borrowings [Member]      
Statement [line items]      
Borrowing costs incurred 13.2 31.0  
Specific Borrowings [Member]      
Statement [line items]      
Borrowing costs incurred 0.0 12.4  
Gruyere [member]      
Statement [line items]      
Specific borrowings relates to related parties $ 0.0 $ 12.4  
[1] Borrowing costs capitalised of US$13.2 million (2019: US$43.4 million) comprise borrowing costs relating to general borrowings of US$13.2 million (2019: US$31.0 million) and specific borrowings of US$nil (2019: US$12.4 million). The specific borrowings of US$nil (2019: US$12.4 million) relate to the Gruyere project and are included in additions to property, plant and equipment of US$nil (2019: US$612.5 million) (refer note 14).