XML 80 R59.htm IDEA: XBRL DOCUMENT v3.8.0.1
INCOME TAXES: - Other (Details)
PEN in Millions, $ in Millions
12 Months Ended
Dec. 31, 2017
PEN
Dec. 31, 2017
USD ($)
item
Dec. 31, 2016
PEN
Dec. 31, 2016
USD ($)
Dec. 31, 2015
PEN
Dec. 31, 2015
USD ($)
Oct. 31, 2017
Sep. 30, 2017
Income Taxes                
Cash, cash equivalents, restricted cash and short-term investments   $ 1,055.3            
Estimated tax on foreign earnings and profit   8,900.0            
U.S. federal income tax   0.0            
State income tax   0.0            
Provisional tax amount   $ 181.1            
Income Tax Rate (as a percent) 35.00% 35.00% 35.00% 35.00% 35.00% 35.00%    
Withholding tax rate on interest             0.46% 0.58%
Changes in unrecognized tax benefits                
Unrecognized tax benefits, opening balance   $ 304.0   $ 400.0   $ 319.4    
Gross increases - tax positions in prior period       3.9   36.3    
Gross decreases - tax positions in prior period   (89.5)            
Gross increases - current-period tax positions       23.3   44.3    
Decreases related to settlements with taxing authorities       (123.2)        
Increase (decrease) in unrecognized tax benefits   (89.5)   (96.0)   80.6    
Unrecognized tax benefits, ending balance   214.5   304.0   $ 400.0    
Amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate   214.5   304.0        
Accrued interest and penalties included in liability for uncertain tax positions   $ 1.9   1.9        
Number of major tax jurisdictions | item   3            
Minera Mexico                
Income Taxes                
Earnings available for dividends to United States   $ 555.5   $ 470.5        
Foreign subsidiaries                
Income Taxes                
Cash, cash equivalents, restricted cash and short-term investments   517.7            
Foreign                
Changes in unrecognized tax benefits                
Unrecognized tax benefits, opening balance                
Unrecognized tax benefits, ending balance   $ 205.7            
Peru                
Income Taxes                
Income Tax Rate (as a percent) 29.50% 29.50% 28.00% 28.00% 28.00% 28.00%    
Royalty charge assessed as a percentage of net sales 1.00% 1.00%            
Increase in royalty tax rate for each 5% increase up to 12% increase in operating income margin (as a percent) 0.75% 0.75%            
Royalty charges | PEN PEN 23.4   PEN 16.8   PEN 22.9      
Provision for royalty tax   $ 2.5   $ 0.0   $ 2.7    
Peruvian special mining tax   23.3   $ 10.8   $ 18.1    
Changes in unrecognized tax benefits                
Unrecognized tax benefits, opening balance                
Unrecognized tax benefits, ending balance   $ 0.0            
Peru | 2015-2016                
Income Taxes                
Income Tax Rate (as a percent) 28.00% 28.00%            
Dividend Tax Rate (as a percent ) 6.80% 6.80%            
Peru | 2017 and later                
Income Taxes                
Income Tax Rate (as a percent) 29.50% 29.50%            
Dividend Tax Rate (as a percent ) 5.00% 5.00%            
Peru | Minimum                
Income Taxes                
Mining royalty tax (as a percent) 1.00% 1.00%            
Increment in operating income margin for royalty tax (as a percent) 5.00% 5.00%            
Special mine tax (as a percent) 2.00% 2.00%            
Peru | Maximum                
Income Taxes                
Mining royalty tax (as a percent) 12.00% 12.00%            
Increment in operating income margin for royalty tax (as a percent) 10.00% 10.00%            
Special mine tax (as a percent) 8.40% 8.40%            
United States | Minimum | Minera Mexico                
Income Taxes                
Excess of financial reporting over tax basis for stock in subsidiary   $ 6,700.0            
Mexico                
Income Taxes                
Income Tax Rate (as a percent) 30.00% 30.00% 30.00% 30.00% 30.00% 30.00%    
Mining royalty tax (as a percent) 7.50% 7.50%            
Mining royalty amount on earnings before taxes   $ 87.8            
Additional royalty tax over gross income from sales of gold, silver and platinum (as a percent) 0.50% 0.50%            
Additional royalty over sales revenue from gold, silver and platinum   $ 0.8            
Income tax payable due to tax consolidation   0.3            
Changes in unrecognized tax benefits                
Unrecognized tax benefits, opening balance                
Unrecognized tax benefits, ending balance   $ 0.0