XML 100 R65.htm IDEA: XBRL DOCUMENT v3.3.1.900
Impairment of Investments (Parenthetical) (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Impairment Of Assets [Line Items]    
Assets held for sale $ 1.0 $ 31.0
Arctic Platinum [Member]    
Impairment Of Assets [Line Items]    
Impairment of investments [1] 30.0  
Assets held for sale $ 1.0  
[1] Following the Group's decision during 2013 to dispose of non-core projects, Arctic Platinum was classified as held for sale and, accordingly, valued at the lower of fair value less cost of disposal or carrying value. During 2015, active marketing activities for the disposal of the project continued. During 2015, Arctic Platinum was impaired by $30.0 million to its fair value less cost of disposal, resulting in a carrying value of US$1.0 million at December 31, 2015.