POLICY LIABILITIES - Reconciliation of Future Policy Benefits (Detail) - USD ($) $ in Millions		Dec. 31, 2024	Dec. 31, 2023
Liability for Future Policy Benefit, Activity [Line Items]
Future policy benefits		$ 70,381	$ 83,718
Deferred reinsurance gain liability		146	175
Intercompany eliminations
Liability for Future Policy Benefit, Activity [Line Items]
Future policy benefits	[1]	(5,760)	(5,017)
Aflac Japan
Liability for Future Policy Benefit, Activity [Line Items]
Deferred profit liability		1,844	1,806
Deferred reinsurance gain liability		806	1,012
Corporate and other
Liability for Future Policy Benefit, Activity [Line Items]
Future policy benefits		5,072	4,225
Cancer | Aflac Japan
Liability for Future Policy Benefit, Activity [Line Items]
Future policy benefits		26,597	32,652
Medical and other health | Aflac Japan
Liability for Future Policy Benefit, Activity [Line Items]
Future policy benefits		8,789	10,560
Life insurance | Aflac Japan
Liability for Future Policy Benefit, Activity [Line Items]
Future policy benefits		19,109	23,243
Life insurance | Aflac U.S.
Liability for Future Policy Benefit, Activity [Line Items]
Future policy benefits		938	911
Accident | Aflac U.S.
Liability for Future Policy Benefit, Activity [Line Items]
Future policy benefits		630	621
Disability | Aflac U.S.
Liability for Future Policy Benefit, Activity [Line Items]
Future policy benefits		695	770
Critical care | Aflac U.S.
Liability for Future Policy Benefit, Activity [Line Items]
Future policy benefits		6,800	7,216
Hospital indemnity | Aflac U.S.
Liability for Future Policy Benefit, Activity [Line Items]
Future policy benefits		775	836
Dental/vision | Aflac U.S.
Liability for Future Policy Benefit, Activity [Line Items]
Future policy benefits		245	272
Other | Aflac Japan
Liability for Future Policy Benefit, Activity [Line Items]
Future policy benefits		3,379	4,090
Other | Aflac U.S.
Liability for Future Policy Benefit, Activity [Line Items]
Future policy benefits		$ 462	$ 521

[1] Elimination entry necessary due to the internal reinsurance transactions with Aflac Re and to recapture a portion of policy liabilities ceded externally as a result of the reinsurance retrocession transaction. See Note 8 for additional details