POLICY LIABILITIES - Summary of Discounted Expected Future Gross Premiums and Future Benefits and Expenses (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022	Dec. 31, 2021
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums	$ 125,393	$ 132,451
Benefits and Expenses	136,089	141,463
Cancer | Aflac Japan
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums	49,689	53,278
Benefits and Expenses	51,692	54,766	$ 72,747
Medical and other health | Aflac Japan
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums	32,246	34,693
Benefits and Expenses	26,527	27,419	36,021
Life insurance | Aflac Japan
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums	11,730	12,951
Benefits and Expenses	30,407	31,954	42,720
Life insurance | Aflac U.S.
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums	1,757	1,663
Benefits and Expenses	1,613	1,526	1,843
Accident | Aflac U.S.
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums	6,494	6,510
Benefits and Expenses	3,094	3,098	3,949
Disability | Aflac U.S.
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums	4,493	4,468
Benefits and Expenses	2,464	2,445	2,871
Critical Care | Aflac U.S.
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums	12,785	12,659
Benefits and Expenses	11,637	11,489	15,388
Hospital Indemnity | Aflac U.S.
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums	3,532	3,483
Benefits and Expenses	2,109	2,074	2,552
Dental/Vision | Aflac U.S.
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums	805	821
Benefits and Expenses	484	488	616
Other | Aflac Japan
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums	1,570	1,697
Benefits and Expenses	5,376	5,582	7,322
Other | Aflac U.S.
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums	292	228
Benefits and Expenses	$ 686	$ 622	$ 837