Related Party Transactions - Additional Information (Detail) - EUR (€) € in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
|
| Disclosure of transactions between related parties [Line Items] | |||
| Termination benefits expense | € 0 | € 2 | € 0 |
| Mr Friese [Member] | |||
| Disclosure of transactions between related parties [Line Items] | |||
| Shares held in the entity common shares held by Board of Directors | 299,323 | 160,357 | 83,122 |
| Reinsurance Subsidiary Of Associate [Member] | Reinsurance contracts held [member] | |||
| Disclosure of transactions between related parties [Line Items] | |||
| Funds withheld under reinsurance contracts | € 300 | ||
| Non cash consideration transferred | 3,200 | ||
| Reinsurance premiums paid | € 3,500 | ||