v3.26.1
Investment contracts without discretionary participation features - Summary of Investment Contracts for Account of General and Separate Accounts (Detail) - EUR (€)
€ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Disclosure of investment contracts general and separate accounts [Line Items]    
Investment contracts liabilities € 97,814 € 91,669
Without Discretionary Participation Features [member]    
Disclosure of investment contracts general and separate accounts [Line Items]    
Investment contracts liabilities 97,814 91,669
Without Discretionary Participation Features [member] | Aegon Risk [Member]    
Disclosure of investment contracts general and separate accounts [Line Items]    
Beginning balance on January 1 12,592 10,222
Deposits 1,798 1,595
Withdrawals (1,653) (1,236)
Interest credited 354 288
Fund charges released (15) (13)
Net exchange differences (1,535) 755
Transfer to/from other headings 1,113 1,038
Other movements (2) (58)
Ending balance 12,652 12,592
Investment contracts liabilities 12,652 12,592
Institutional guaranteed products 157 182
Fixed annuities 12,466 12,378
Other 29 32
Without Discretionary Participation Features [member] | Policyholder Risk [Member]    
Disclosure of investment contracts general and separate accounts [Line Items]    
Beginning balance on January 1 79,078 65,044
Deposits 15,135 14,932
Withdrawals (12,788) (11,807)
Interest credited 11,004 8,467
Fund charges released (384) (367)
Net exchange differences (6,241) 3,868
Transfer to/from other headings (647) (1,060)
Other movements 4 1
Ending balance 85,161 79,078
Investment contracts liabilities for separate account € 85,161 € 79,078