| 
                Total assets
             | 
                        
                2.6B
             | 
                        
                2.6B
             | 
                        
                2.7B
             | 
                        
                2.6B
             | 
                    
                
                        | 
                Current assets
             | 
                        
                2.3B
             | 
                        
                2.3B
             | 
                        
                2.3B
             | 
                        
                2.3B
             | 
                    
                
                        | 
                Cash
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Cash equivalents
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Cash and cash equivalents
             | 
                        
                2.1B
             | 
                        
                2.1B
             | 
                        
                2.1B
             | 
                        
                2.1B
             | 
                    
                
                        | 
                Other short term investments
             | 
                        
                21.5M
             | 
                        
                29.7M
             | 
                        
                35.6M
             | 
                        
                50.4M
             | 
                    
                
                        | 
                Accounts receivable
             | 
                        
                58.1M
             | 
                        
                43.2M
             | 
                        
                26.0M
             | 
                        
                30.0M
             | 
                    
                
                        | 
                Other receivables
             | 
                        
                4.1M
             | 
                        
                5.2M
             | 
                        
                7.9M
             | 
                        
                3.2M
             | 
                    
                
                        | 
                Inventory
             | 
                        
                89.3M
             | 
                        
                91.0M
             | 
                        
                114.0M
             | 
                        
                104.8M
             | 
                    
                
                        | 
                Prepaid assets
             | 
                        
                11.7M
             | 
                        
                15.9M
             | 
                        
                15.4M
             | 
                        
                25.0M
             | 
                    
                
                        | 
                Restricted cash
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Assets held for sale
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Hedging assets
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Other current assets
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Non current assets
             | 
                        
                343.0M
             | 
                        
                342.2M
             | 
                        
                355.6M
             | 
                        
                318.0M
             | 
                    
                
                        | 
                Properties
             | 
                        
                289.5M
             | 
                        
                280.4M
             | 
                        
                285.8M
             | 
                        
                289.5M
             | 
                    
                
                        | 
                Land and improvements
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Machinery furniture equipment
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Construction in progress
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Leases
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Accumulated depreciation
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Goodwill
             | 
                        
                53.0M
             | 
                        
                61.3M
             | 
                        
                69.3M
             | 
                        
                27.8M
             | 
                    
                
                        | 
                Investment properties
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Financial assets
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Intangible assets
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Investments and advances
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Other non current assets
             | 
                        
                518K
             | 
                        
                518K
             | 
                        
                518K
             | 
                        
                693K
             | 
                    
                
                        | 
                Total liabilities
             | 
                        
                129.9M
             | 
                        
                131.2M
             | 
                        
                153.8M
             | 
                        
                109.5M
             | 
                    
                
                        | 
                Current liabilities
             | 
                        
                112.6M
             | 
                        
                114.0M
             | 
                        
                135.8M
             | 
                        
                108.4M
             | 
                    
                
                        | 
                Accounts payable
             | 
                        
                52.5M
             | 
                        
                45.1M
             | 
                        
                47.6M
             | 
                        
                46.8M
             | 
                    
                
                        | 
                Accrued expenses
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Short term debt
             | 
                        
                0
             | 
                        
                0
             | 
                        
                0
             | 
                        
                0
             | 
                    
                
                        | 
                Deferred revenue
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Tax payable
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Pensions
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Other current liabilities
             | 
                        
                2.8M
             | 
                        
                2.1M
             | 
                        
                1.1M
             | 
                        
                819K
             | 
                    
                
                        | 
                Non current liabilities
             | 
                        
                17.3M
             | 
                        
                17.2M
             | 
                        
                17.9M
             | 
                        
                1.1M
             | 
                    
                
                        | 
                Long term provisions
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Long term debt
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Provision for risks and charges
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Deferred liabilities
             | 
                        
                0
             | 
                        
                —
             | 
                        
                0
             | 
                        
                0
             | 
                    
                
                        | 
                Derivative product liabilities
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Other non current liabilities
             | 
                        
                17.3M
             | 
                        
                17.2M
             | 
                        
                17.9M
             | 
                        
                1.1M
             | 
                    
                
                        | 
                Shareholders equity
             | 
                        
                
             | 
                        
                
             | 
                        
                
             | 
                        
                
             | 
                    
                
                        | 
                Common stock
             | 
                        
                964.1M
             | 
                        
                964.1M
             | 
                        
                964.1M
             | 
                        
                964.1M
             | 
                    
                
                        | 
                Retained earnings
             | 
                        
                -29.9M
             | 
                        
                -149.1M
             | 
                        
                -140.3M
             | 
                        
                -110.0M
             | 
                    
                
                        | 
                Other shareholders equity
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Total shareholders equity
             | 
                        
                2.5B
             | 
                        
                2.5B
             | 
                        
                2.5B
             | 
                        
                2.5B
             | 
                    
                
                        | 
                Additional paid in capital
             | 
                        
                1.5B
             | 
                        
                1.7B
             | 
                        
                1.7B
             | 
                        
                1.7B
             | 
                    
                
                        | 
                Treasury stock
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                    
                
                        | 
                Minority interest
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             | 
                        
                —
             |