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Trade and Other Payables - Summary of Trade and Other Payables (Parenthetical) (Detail) - USD ($)
$ in Millions
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Disclosure of trade and other payables [line items]      
Gold and foreign exchange derivative contracts $ 127.6 $ 22.6 [1] $ 3.3
Australian gold derivative contracts [member]      
Disclosure of trade and other payables [line items]      
Gold and foreign exchange derivative contracts 78.3 12.3  
Gold derivative contracts at south deep [member]      
Disclosure of trade and other payables [line items]      
Gold and foreign exchange derivative contracts 12.6 1.6  
Australian foreign exchange derivative contracts [member]      
Disclosure of trade and other payables [line items]      
Gold and foreign exchange derivative contracts 0.3 8.7  
Gold derivative contracts at ghana [member]      
Disclosure of trade and other payables [line items]      
Gold and foreign exchange derivative contracts $ 36.4 $ 0.0  
[1] Refer note 42.