v3.26.1
Investments - Summary of Financial Assets Excluding Derivatives (Detail) - EUR (€)
€ in Millions
Dec. 31, 2025
Dec. 31, 2024
Disclosure of financial assets [line items]    
Total € 69,293 € 76,020
Fair value 59,574 65,375
Financial Assets Excluding Derivatives Measurement Category [Member]    
Disclosure of financial assets [line items]    
FVOCI (With recycling) 49,747 54,677
FVOCI (no recycling) 10 39
Amortized cost 9,719 10,645
Financial assets measured at FVPL – designated 2,066 2,356
Financial assets measured at FVPL – mandatory 7,306 7,661
Total 68,848 75,377
Fair value 68,078 74,159
Financial Assets Excluding Derivatives Measurement Category [Member] | Investments For Risk Of Policy Holders [member]    
Disclosure of financial assets [line items]    
Total 215,814 217,824
Financial Assets Excluding Derivatives Measurement Category [Member] | Shares [member]    
Disclosure of financial assets [line items]    
FVOCI (no recycling) 10 39
Financial assets measured at FVPL – mandatory 263 279
Total 273 317
Fair value 273 317
Financial Assets Excluding Derivatives Measurement Category [Member] | Shares [member] | Investments For Risk Of Policy Holders [member]    
Disclosure of financial assets [line items]    
Total 15,321 15,198
Financial Assets Excluding Derivatives Measurement Category [Member] | Debt securities [member]    
Disclosure of financial assets [line items]    
FVOCI (With recycling) 47,411 52,211
Amortized cost 36 36
Financial assets measured at FVPL – designated 1,123 1,400
Financial assets measured at FVPL – mandatory 1,315 985
Total 49,884 54,632
Fair value 49,884 54,632
Financial Assets Excluding Derivatives Measurement Category [Member] | Debt securities [member] | Investments For Risk Of Policy Holders [member]    
Disclosure of financial assets [line items]    
Total 6,318 6,259
Financial Assets Excluding Derivatives Measurement Category [Member] | Money market and other short-term investments [member]    
Disclosure of financial assets [line items]    
FVOCI (With recycling) 2,308 2,435
Financial assets measured at FVPL – designated 146 157
Financial assets measured at FVPL – mandatory 1,722 1,939
Total 4,176 4,531
Fair value 4,176 4,531
Financial Assets Excluding Derivatives Measurement Category [Member] | Money market and other short-term investments [member] | Investments For Risk Of Policy Holders [member]    
Disclosure of financial assets [line items]    
Total 1,788 1,541
Financial Assets Excluding Derivatives Measurement Category [Member] | Deposits with financial institutions [member]    
Disclosure of financial assets [line items]    
Amortized cost 11 11
Total 11 11
Fair value 11 11
Financial Assets Excluding Derivatives Measurement Category [Member] | Deposits with financial institutions [member] | Investments For Risk Of Policy Holders [member]    
Disclosure of financial assets [line items]    
Total 1,716 2,052
Financial Assets Excluding Derivatives Measurement Category [Member] | Unconsolidated Investment Funds [member] | Investments For Risk Of Policy Holders [member]    
Disclosure of financial assets [line items]    
Total 190,671 192,775
Financial Assets Excluding Derivatives Measurement Category [Member] | Loans [member]    
Disclosure of financial assets [line items]    
Amortized cost 9,672 10,598
Financial assets measured at FVPL – designated 82 82
Total 9,754 10,680
Fair value 8,985 9,462
Financial Assets Excluding Derivatives Measurement Category [Member] | Other [member]    
Disclosure of financial assets [line items]    
FVOCI (With recycling) 28 31
Financial assets measured at FVPL – designated 716 718
Financial assets measured at FVPL – mandatory 4,005 4,458
Total 4,749 5,207
Fair value € 4,749 € 5,207