v3.26.1
Net income / (expenses) on reinsurance held - Summary of net income / (expenses) on reinsurance held (Detail) - EUR (€)
€ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Disclosure of Detailed Information About Net Expenses on Reinsurance Held [Line Items]      
Net income / (expenses) on reinsurance held € 836 € 325 € 182
Insurance contracts issued [member]      
Disclosure of Detailed Information About Net Expenses on Reinsurance Held [Line Items]      
Net income / (expenses) on reinsurance held 836 325 182
Insurance contracts issued [member] | Contracts measured under Non-PAA [member]      
Disclosure of Detailed Information About Net Expenses on Reinsurance Held [Line Items]      
Assumption changes that relate to (a reversal of) underlying onerous contracts 33 56 31
Experience adjustments that relate to (a reversal of) underlying onerous contracts 586 398 516
CSM recognized for service received (11) (14) (26)
Release of the contractual service margin for services received (72) (83) (118)
Experience adjustments on current service 300 (36) (217)
Experience adjustments on incurred claims 0 3 (2)
New reinsurance contracts issued/acquired 1 1 (17)
Initial recognition of onerous underlying contracts 0 0 12
Establishing of loss recovery component from onerous underlying contracts 0 0 7
Reversals of a loss-recovery component other than changes in the FCF of reinsurance contracts held 0 (1) (3)
Net income / (expenses) on reinsurance held 837 325 181
Insurance contracts issued [member] | Contracts measured under the PAA [member]      
Disclosure of Detailed Information About Net Expenses on Reinsurance Held [Line Items]      
Net income / (expenses) on reinsurance held € (1) € 0 € 1