Income Tax (Tables)
   | 
12 Months Ended | 
Dec. 31, 2023  | 
| Major components of tax expense (income) [abstract] | 
 
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| Summary of Income Tax Expense | 
 Income tax expense is as follows: 
  
      
       
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           | 
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        For the year ended December 31,  | 
           | 
        
       
           | 
           | 
        2023  | 
           | 
           | 
        2022  | 
           | 
           | 
        2021  | 
           | 
        
       
           | 
           | 
        (EUR thousand)  | 
           | 
        
       
        Current income tax:  | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
        
       
        Current Taxes  | 
           | 
           | 
        62,610  | 
           | 
           | 
           | 
        57,400  | 
           | 
           | 
           | 
        35,093  | 
           | 
        
       
        Prior Years Taxes  | 
           | 
           | 
        (1,932  | 
        )  | 
           | 
           | 
        215  | 
           | 
           | 
           | 
        (6,544  | 
        )  | 
        
       
        Deferred tax:  | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
           | 
        
       
        Deferred Taxes  | 
           | 
           | 
        (16,815  | 
        )  | 
           | 
           | 
        (12,990  | 
        )  | 
           | 
           | 
        2,855  | 
           | 
        
       
        Income tax expense reported in the statement of profit or loss  | 
           | 
           | 
        43,863  | 
           | 
           | 
           | 
        44,625  | 
           | 
           | 
           | 
        31,404  | 
           | 
        
       
  
  
  
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| Summary of Deferred Tax Charged to OCI | 
      
       
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        For the year ended December 31,  | 
           | 
        
       
           | 
           | 
        2023  | 
           | 
           | 
        2022  | 
           | 
           | 
        2021  | 
           | 
        
       
           | 
           | 
        (EUR thousand)  | 
           | 
        
       
        Deferred tax related to items recognized in OCI during in the year:  | 
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           | 
           | 
           | 
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           | 
           | 
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        Gains/(losses) from remeasurement of employee of defined benefit plans and of agent termination plans  | 
           | 
           | 
        15  | 
           | 
           | 
           | 
        (236  | 
        )  | 
           | 
           | 
        26  | 
           | 
        
       
        Change in the fair value of hedging instruments  | 
           | 
           | 
        932  | 
           | 
           | 
           | 
        (2,043  | 
        )  | 
           | 
           | 
        (653  | 
        )  | 
        
       
        Deferred tax charged to OCI  | 
           | 
           | 
        947  | 
           | 
           | 
           | 
        (2,279  | 
        )  | 
           | 
           | 
        (627  | 
        )  | 
        
       
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| Schedule of Reconciliation of Effective Tax Rate | 
 The table below provides a reconciliation between actual income tax expense and the theoretical income tax expense, calculated on the basis of the applicable corporate tax rate in effect in Italy. 
  
      
       
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           | 
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        For the year ended December 31,  | 
           | 
        
       
           | 
           | 
        2023  | 
           | 
           | 
        2022  | 
           | 
           | 
        2021  | 
           | 
        
       
           | 
           | 
        (EUR thousand)  | 
           | 
        
       
        Accounting profit before income tax  | 
           | 
           | 
        189,553  | 
           | 
           | 
           | 
        187,641  | 
           | 
           | 
           | 
        165,673  | 
           | 
        
       
        Statutory income tax rate of 27.9%  | 
           | 
           | 
        52,885  | 
           | 
           | 
           | 
        52,202  | 
           | 
           | 
           | 
        46,223  | 
           | 
        
       
        Prior years taxes  | 
           | 
           | 
        (1,932  | 
        )  | 
           | 
           | 
        215  | 
           | 
           | 
           | 
        (6,544  | 
        )  | 
        
       
        DTA not recognized on tax losses carry-forward  | 
           | 
           | 
        1,854  | 
           | 
           | 
           | 
        750  | 
           | 
           | 
           | 
        (1,947  | 
        )  | 
        
       
        DTA on temporary/tax losses non recognized  | 
           | 
           | 
        (2,810  | 
        )  | 
           | 
           | 
        —  | 
           | 
           | 
           | 
        —  | 
           | 
        
       
        Taxes effect on unremitted earnings  | 
           | 
           | 
        827  | 
           | 
           | 
           | 
        1,488  | 
           | 
           | 
           | 
        400  | 
           | 
        
       
        Tax grants/not taxable items  | 
           | 
           | 
        (5,097  | 
        )  | 
           | 
           | 
        (8,477  | 
        )  | 
           | 
           | 
        (1,157  | 
        )  | 
        
       
        Tax exemption on gain from the sale of an associate  | 
           | 
        —  | 
           | 
           | 
           | 
        —  | 
           | 
           | 
           | 
        (3,378  | 
        )  | 
        
       
        Different foreign tax rate effect  | 
           | 
           | 
        (2,244  | 
        )  | 
           | 
           | 
        (1,553  | 
        )  | 
           | 
           | 
        (2,193  | 
        )  | 
        
       
        DTA/DTL effect previous years  | 
           | 
           | 
        380  | 
           | 
           | 
           | 
        —  | 
           | 
           | 
           | 
        —  | 
           | 
        
       
        At the effective income tax rate of 23.1% (23.8% in 2022, 19.0% in 2021)  | 
           | 
           | 
        43,863  | 
           | 
           | 
           | 
        44,625  | 
           | 
           | 
           | 
        31,404  | 
           | 
        
       
        Income tax expense reported in the statement of profit or loss  | 
           | 
           | 
        43,863  | 
           | 
           | 
           | 
        44,625  | 
           | 
           | 
           | 
        31,404  | 
           | 
        
       
The Group's effective tax rate for the year ended December 31, 2023, decreased to 23.1% compared to 23.8% for the year ended December 31, 2022. Considering that the accounting profit before income tax is basically unchanged, the lower tax impact is due to a sum of several different effects, as explained in the table above. 
The Group's e
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| Summary of Timing of Tax Losses Carryforwards | 
 The breakdown on the timing of tax losses carry-forwards is as follows: 
  
      
       
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           | 
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        At December 31,  | 
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        At December 31,  | 
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           | 
           | 
        2023  | 
           | 
           | 
        2022  | 
           | 
        
       
           | 
           | 
        (EUR thousand)  | 
           | 
        
       
        Timing of unrecognized tax losses carry-forwards  | 
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        2023  | 
           | 
        —  | 
           | 
           | 
           | 
        336  | 
           | 
        
       
        2024  | 
           | 
        —  | 
           | 
           | 
           | 
        369  | 
           | 
        
       
        2025  | 
           | 
        —  | 
           | 
           | 
           | 
        331  | 
           | 
        
       
        2026  | 
           | 
        —  | 
           | 
           | 
           | 
        334  | 
           | 
        
       
        2027  | 
           | 
        —  | 
           | 
           | 
           | 
        3,860  | 
           | 
        
       
        2028  | 
           | 
        —  | 
           | 
           | 
           | 
        404  | 
           | 
        
       
        2029  | 
           | 
        —  | 
           | 
           | 
           | 
        129  | 
           | 
        
       
        Unlimited  | 
           | 
           | 
        8,377  | 
           | 
           | 
           | 
        2,215  | 
           | 
        
       
        Total unrecognized tax losses  | 
           | 
           | 
        8,377  | 
           | 
           | 
           | 
        7,978  | 
           | 
        
       
The change in unrecognized tax losses is related to both the recognition of deferred tax assets and the use of tax losses expiring within 2029. 
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| Summary of Deferred Tax Assets and Deferred Tax Liabilities | 
 The analysis of deferred tax assets and deferred tax liabilities as at December 31, 2023 and 2022 is as follows: 
  
      
       
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           | 
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        At December 31,  | 
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           | 
        At December 31,  | 
           | 
        
       
           | 
           | 
        2023  | 
           | 
           | 
        2022  | 
           | 
        
       
           | 
           | 
        (EUR thousand)  | 
           | 
        
       
        Intangible assets  | 
           | 
           | 
        (1,649  | 
        )  | 
           | 
           | 
        (4,179  | 
        )  | 
        
       
        Property, plant and equipment  | 
           | 
           | 
        30,150  | 
           | 
           | 
           | 
        19,746  | 
           | 
        
       
        Contract balances  | 
           | 
           | 
        (13,552  | 
        )  | 
           | 
           | 
        (12,329  | 
        )  | 
        
       
        Revaluations of investment properties to fair value  | 
           | 
           | 
        5,712  | 
           | 
           | 
           | 
        6,807  | 
           | 
        
       
        Expected credit losses  | 
           | 
           | 
        1,279  | 
           | 
           | 
           | 
        1,217  | 
           | 
        
       
        Derivatives  | 
           | 
           | 
        (708  | 
        )  | 
           | 
           | 
        (1,640  | 
        )  | 
        
       
        Leases  | 
           | 
           | 
        308  | 
           | 
           | 
           | 
        331  | 
           | 
        
       
        Long term incentives  | 
           | 
           | 
        12  | 
           | 
           | 
           | 
        51  | 
           | 
        
       
        Provisions  | 
           | 
           | 
        6,845  | 
           | 
           | 
           | 
        6,631  | 
           | 
        
       
        Accruals and other provisions  | 
           | 
           | 
        578  | 
           | 
           | 
           | 
        164  | 
           | 
        
       
        Tax losses carry forward  | 
           | 
           | 
        36,251  | 
           | 
           | 
           | 
        26,941  | 
           | 
        
       
        Unremitted earnings  | 
           | 
           | 
        (2,260  | 
        )  | 
           | 
           | 
        (2,260  | 
        )  | 
        
       
        Start up costs IPO SG spa  | 
           | 
           | 
        2,684  | 
           | 
           | 
           | 
        4,026  | 
           | 
        
       
        Share-based compensation plans  | 
           | 
        —  | 
           | 
           | 
           | 
        325  | 
           | 
        
       
        Other effects  | 
           | 
           | 
        977  | 
           | 
           | 
           | 
        2,427  | 
           | 
        
       
        Deferred tax assets, net  | 
           | 
           | 
        66,627  | 
           | 
           | 
           | 
        48,258  | 
           | 
        
       
        Reflected in the statement of financial position as follows:  | 
           | 
           | 
           | 
           | 
           | 
           | 
        
       
        Deferred tax assets  | 
           | 
           | 
        76,251  | 
           | 
           | 
           | 
        69,210  | 
           | 
        
       
        Deferred tax liabilities  | 
           | 
           | 
        (9,624  | 
        )  | 
           | 
           | 
        (20,952  | 
        )  | 
        
       
        Deferred tax assets, net  | 
           | 
           | 
        66,627  | 
           | 
           | 
           | 
        48,258  | 
           | 
        
       
  
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| Schedule of Reconciliation of Net Deferred Tax Assets | 
 The reconciliation of net deferred tax assets is as follows: 
  
      
       
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           | 
           | 
        2023  | 
           | 
           | 
        2022  | 
           | 
        
       
           | 
           | 
        (EUR thousand)  | 
           | 
        
       
        As of January 1  | 
           | 
           | 
        48,258  | 
           | 
           | 
           | 
        36,772  | 
           | 
        
       
        Tax expense during the period recognized in profit or loss  | 
           | 
           | 
        16,815  | 
           | 
           | 
           | 
        12,990  | 
           | 
        
       
        Tax income/(expense) during the period recognized in OCI  | 
           | 
           | 
        947  | 
           | 
           | 
           | 
        (2,279  | 
        )  | 
        
       
        Other effect  | 
           | 
           | 
        607  | 
           | 
           | 
           | 
        775  | 
           | 
        
       
        As at December 31  | 
           | 
           | 
        66,627  | 
           | 
           | 
           | 
        48,258  | 
           | 
        
       
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