XML 54 R41.htm IDEA: XBRL DOCUMENT v3.8.0.1
COMMITMENTS AND CONTINGENCIES: - Environmental Costs (Details)
$ in Millions, MXN in Billions
 1 Months Ended 3 Months Ended 6 Months Ended 9 Months Ended 12 Months Ended
Sep. 15, 2014
MXN
Sep. 15, 2014
USD ($)
Sep. 30, 2017
lawsuit
item
m³
Mar. 31, 2014
Sep. 30, 2016
lawsuit
Jun. 30, 2015
lawsuit
item
Sep. 30, 2017
USD ($)
lawsuit
item
m³
Sep. 30, 2016
USD ($)
Dec. 31, 2015
USD ($)
lawsuit
item
Dec. 31, 2014
item
m³
Dec. 31, 2011
category
person
Dec. 31, 2016
lawsuit
Environmental costs                        
Environmental capital investment | $             $ 155.6 $ 159.9        
Number of collective action lawsuits           6            
Number of subsidiaries against which lawsuits were filed | item           2            
Number of collective action lawsuits dismissed           2            
Remaining number of lawsuits           4            
Remaining number of Collective action lawsuits           2            
Number of civil actions seeking damages                       3
Number of constitutional action lawsuits                 4      
Number of subsidiaries to which environmental impact authorizations were granted | item                 1      
Buenavista del Cobre, S.A. de C.V                        
Environmental costs                        
Volume of copper sulfate solution (in cubic meters) | m³                   40,000    
Excess provision reversed on closure of trust | $             $ 10.2          
Estimated total damages | $                 $ 136.4      
Number of civil actions seeking damages     32       32   8      
Buenavista del Cobre, S.A. de C.V | Maximum                        
Environmental costs                        
Amount committed to the Mexican Federal Government to establish a trust MXN 2 $ 150.0                    
Buenavista del Cobre, S.A. de C.V | Minimum                        
Environmental costs                        
Number of workers to clean the river | item                   1,200    
Peru                        
Environmental costs                        
Environmental capital investment | $             $ 60.5 58.7        
Number of atmospheric basins established that require further attention | item             3          
AQS, new hours | item     24                  
AQS, new micrograms of SO2 | m³     250                  
AQS, old hours | item     24                  
Revised air quality standards for sulfur dioxide as per new environmental regulation (in micrograms per cubic meter) | m³     20                  
AQS, new micrograms of gaseous mercury | m³             2          
Mean monthly AQS | m³     1.5                  
Number of months for identification of contaminated sites and around in facilities       12 months                
Period for preparation of decontamination plan       P30M                
Period of extension for preparation of decontamination plan       1 year                
Number of days in which results of soil confirmation tests are to be presented to authorities       30 days                
Mexico                        
Environmental costs                        
Environmental capital investment | $             $ 95.1 $ 101.2        
Number of categories of collective actions | category                     3  
Minimum number of people claiming injury due to collective action initiative in Civil Federal Procedures Code (CFPC) | person                     30  
Francisca Garcia Enriquez                        
Environmental costs                        
Number of additional constitutional lawsuits filed                 2      
Mario Alberto Salcido et al; Maria Elena Heredia Bustamante et al; Martin Eligio Ortiz Gamez et al and Maria de los Angeles Enriquez Bacame et al                        
Environmental costs                        
Number of additional constitutional lawsuits filed         4