v3.26.1
POLICY LIABILITIES - Summary of Undiscounted Expected Future Gross Premiums and Expected Future Policy Benefits and Expenses (Details) - USD ($)
$ in Millions
Mar. 31, 2026
Dec. 31, 2025
Liability for Future Policy Benefit, Activity [Line Items]    
Gross Premiums $ 141,365 $ 143,474
Benefits and Expenses 170,011 173,047
Aflac Japan | Cancer    
Liability for Future Policy Benefit, Activity [Line Items]    
Gross Premiums 51,004 52,505
Benefits and Expenses 53,308 54,844
Aflac Japan | Medical and other health    
Liability for Future Policy Benefit, Activity [Line Items]    
Gross Premiums 31,455 32,757
Benefits and Expenses 33,991 35,043
Aflac Japan | Life insurance    
Liability for Future Policy Benefit, Activity [Line Items]    
Gross Premiums 10,468 10,781
Benefits and Expenses 36,171 37,340
Aflac Japan | Other    
Liability for Future Policy Benefit, Activity [Line Items]    
Gross Premiums 1,297 1,351
Benefits and Expenses 6,216 6,419
Aflac U.S. | Life insurance    
Liability for Future Policy Benefit, Activity [Line Items]    
Gross Premiums 3,527 3,326
Benefits and Expenses 4,115 3,948
Aflac U.S. | Accident    
Liability for Future Policy Benefit, Activity [Line Items]    
Gross Premiums 8,545 8,560
Benefits and Expenses 4,638 4,660
Aflac U.S. | Disability    
Liability for Future Policy Benefit, Activity [Line Items]    
Gross Premiums 5,720 5,697
Benefits and Expenses 3,055 3,033
Aflac U.S. | Critical care    
Liability for Future Policy Benefit, Activity [Line Items]    
Gross Premiums 19,272 19,182
Benefits and Expenses 20,020 19,971
Aflac U.S. | Hospital indemnity    
Liability for Future Policy Benefit, Activity [Line Items]    
Gross Premiums 4,812 4,757
Benefits and Expenses 3,052 3,027
Aflac U.S. | Dental/vision    
Liability for Future Policy Benefit, Activity [Line Items]    
Gross Premiums 1,074 1,081
Benefits and Expenses 659 657
Aflac U.S. | Other    
Liability for Future Policy Benefit, Activity [Line Items]    
Gross Premiums 4,191 3,477
Benefits and Expenses $ 4,786 $ 4,105