| 
                Total assets
             | 
                        
                13.1B
             | 
                        
                12.9B
             | 
                        
                13.1B
             | 
                        
                12.9B
             | 
                    
                
                        | 
                Current assets
             | 
                        
                2.1B
             | 
                        
                2.0B
             | 
                        
                2.4B
             | 
                        
                2.2B
             | 
                    
                
                        | 
                Cash
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Cash equivalents
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Cash and cash equivalents
             | 
                        
                186.1M
             | 
                        
                166.6M
             | 
                        
                334M
             | 
                        
                351.7M
             | 
                    
                
                        | 
                Other short term investments
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Accounts receivable
             | 
                        
                587.4M
             | 
                        
                587.5M
             | 
                        
                573.7M
             | 
                        
                549.5M
             | 
                    
                
                        | 
                Other receivables
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Inventory
             | 
                        
                1.2B
             | 
                        
                1.1B
             | 
                        
                1.3B
             | 
                        
                1.2B
             | 
                    
                
                        | 
                Prepaid assets
             | 
                        
                51.5M
             | 
                        
                47.6M
             | 
                        
                61.7M
             | 
                        
                41.7M
             | 
                    
                
                        | 
                Restricted cash
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Assets held for sale
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Hedging assets
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Other current assets
             | 
                        
                74.1M
             | 
                        
                73.4M
             | 
                        
                77.2M
             | 
                        
                70.6M
             | 
                    
                
                        | 
                Non current assets
             | 
                        
                10.9B
             | 
                        
                10.9B
             | 
                        
                10.7B
             | 
                        
                10.7B
             | 
                    
                
                        | 
                Properties
             | 
                        
                211M
             | 
                        
                220M
             | 
                        
                218.9M
             | 
                        
                136.8M
             | 
                    
                
                        | 
                Land and improvements
             | 
                        
                94.1M
             | 
                        
                93.3M
             | 
                        
                90.1M
             | 
                        
                95.1M
             | 
                    
                
                        | 
                Machinery furniture equipment
             | 
                        
                1.6B
             | 
                        
                1.4B
             | 
                        
                1.3B
             | 
                        
                1.2B
             | 
                    
                
                        | 
                Construction in progress
             | 
                        
                247.1M
             | 
                        
                223.3M
             | 
                        
                238.7M
             | 
                        
                211.9M
             | 
                    
                
                        | 
                Leases
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Accumulated depreciation
             | 
                        
                -1.3B
             | 
                        
                -1.3B
             | 
                        
                -1.1B
             | 
                        
                -1.1B
             | 
                    
                
                        | 
                Goodwill
             | 
                        
                14.0B
             | 
                        
                14.0B
             | 
                        
                14.0B
             | 
                        
                14.3B
             | 
                    
                
                        | 
                Investment properties
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Financial assets
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Intangible assets
             | 
                        
                3.5B
             | 
                        
                3.5B
             | 
                        
                3.5B
             | 
                        
                3.6B
             | 
                    
                
                        | 
                Investments and advances
             | 
                        
                282.7M
             | 
                        
                264.1M
             | 
                        
                283M
             | 
                        
                301.3M
             | 
                    
                
                        | 
                Other non current assets
             | 
                        
                176.7M
             | 
                        
                148.1M
             | 
                        
                153.4M
             | 
                        
                140.6M
             | 
                    
                
                        | 
                Total liabilities
             | 
                        
                7.8B
             | 
                        
                7.8B
             | 
                        
                8.4B
             | 
                        
                8.5B
             | 
                    
                
                        | 
                Current liabilities
             | 
                        
                2.9B
             | 
                        
                3.1B
             | 
                        
                3.4B
             | 
                        
                3.2B
             | 
                    
                
                        | 
                Accounts payable
             | 
                        
                1.2B
             | 
                        
                1.1B
             | 
                        
                1.2B
             | 
                        
                1.1B
             | 
                    
                
                        | 
                Accrued expenses
             | 
                        
                775.7M
             | 
                        
                795.5M
             | 
                        
                649.5M
             | 
                        
                751.2M
             | 
                    
                
                        | 
                Short term debt
             | 
                        
                748.3M
             | 
                        
                1.1B
             | 
                        
                1.5B
             | 
                        
                1.3B
             | 
                    
                
                        | 
                Deferred revenue
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Tax payable
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Pensions
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Other current liabilities
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Non current liabilities
             | 
                        
                4.9B
             | 
                        
                4.7B
             | 
                        
                5.0B
             | 
                        
                5.3B
             | 
                    
                
                        | 
                Long term provisions
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Long term debt
             | 
                        
                3.8B
             | 
                        
                3.5B
             | 
                        
                3.8B
             | 
                        
                4.1B
             | 
                    
                
                        | 
                Provision for risks and charges
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Deferred liabilities
             | 
                        
                840.5M
             | 
                        
                861.2M
             | 
                        
                866.3M
             | 
                        
                792.3M
             | 
                    
                
                        | 
                Derivative product liabilities
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Other non current liabilities
             | 
                        
                145.1M
             | 
                        
                175M
             | 
                        
                169M
             | 
                        
                144.6M
             | 
                    
                
                        | 
                Shareholders equity
             | 
                        
                
             | 
                        
                
             | 
                        
                
             | 
                        
                
             | 
                    
                
                        | 
                Common stock
             | 
                        
                2.2B
             | 
                        
                2.2B
             | 
                        
                2.1B
             | 
                        
                2.1B
             | 
                    
                
                        | 
                Retained earnings
             | 
                        
                3.5B
             | 
                        
                3.2B
             | 
                        
                3.0B
             | 
                        
                2.8B
             | 
                    
                
                        | 
                Other shareholders equity
             | 
                        
                -491.2M
             | 
                        
                -388.6M
             | 
                        
                -480.6M
             | 
                        
                -426.5M
             | 
                    
                
                        | 
                Total shareholders equity
             | 
                        
                5.3B
             | 
                        
                5.1B
             | 
                        
                4.7B
             | 
                        
                4.4B
             | 
                    
                
                        | 
                Additional paid in capital
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Treasury stock
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Minority interest
             | 
                        
                25.8M
             | 
                        
                22.8M
             | 
                        
                18.7M
             | 
                        
                14.5M
             |