POLICY LIABILITIES - Schedule of Changes in Present Value of Expected Net Premiums and Expected Future Policy Benefits (Details) - USD ($) $ in Millions		3 Months Ended	12 Months Ended
		Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Present value of expected future policy benefits:
Net liability for future policy benefits		$ 91,293	$ 88,241
Cancer | Aflac Japan
Present value of expected premiums:
Beginning balance		19,298	25,893
Beginning balance at original discount rate		18,221	22,470
Effect of changes in cash flow assumptions			0	$ (639)
Effect of actual variances from expected experience			(120)	(284)
Adjusted beginning of period balance			18,101	21,547
Issuances		229	947
Interest accrual		111	459
Net premium earned	[1]	(420)	(1,734)
Foreign currency translation		(109)	(2,997)
Other		0	(1)
Ending balance at original discount rate		17,912	18,221	22,470
Effect of change in discount rate assumptions		1,542	1,077
Ending balance		19,454	19,298	25,893
Present value of expected future policy benefits:
Beginning balance		54,766	72,747
Beginning balance at original discount rate		47,677	56,807
Effect of changes in cash flow assumptions			0	(721)
Effect of actual variances from expected experience			(136)	(333)
Adjusted beginning of period balance			47,541	55,753
Issuances		232	960
Interest accrual		396	1,599
Benefit payments		(825)	(3,050)
Foreign currency translation		(295)	(7,585)
Other		0	0
Ending balance at original discount rate		47,049	47,677	56,807
Effect of change in discount rate assumptions		8,750	7,089
Ending balance		55,799	54,766	72,747
Net liability for future policy benefits		36,345	35,468
Less: reinsurance		0	0
Net liability for future policy benefits after reinsurance recoverable		36,345	35,468
Medical and other health | Aflac Japan
Present value of expected premiums:
Beginning balance		16,714	21,174
Beginning balance at original discount rate		16,195	18,681
Effect of changes in cash flow assumptions			0	317
Effect of actual variances from expected experience			(25)	61
Adjusted beginning of period balance			16,170	19,059
Issuances		104	639
Interest accrual		92	364
Net premium earned	[1]	(344)	(1,376)
Foreign currency translation		(100)	(2,488)
Other		0	(3)
Ending balance at original discount rate		15,922	16,195	18,681
Effect of change in discount rate assumptions		1,045	519
Ending balance		16,967	16,714	21,174
Present value of expected future policy benefits:
Beginning balance		27,419	36,021
Beginning balance at original discount rate		27,566	31,398
Effect of changes in cash flow assumptions			0	352
Effect of actual variances from expected experience			(24)	83
Adjusted beginning of period balance			27,542	31,833
Issuances		108	646
Interest accrual		163	642
Benefit payments		(367)	(1,375)
Foreign currency translation		(171)	(4,180)
Other		0	0
Ending balance at original discount rate		27,275	27,566	31,398
Effect of change in discount rate assumptions		1,164	(147)
Ending balance		28,439	27,419	36,021
Net liability for future policy benefits		11,472	10,705
Less: reinsurance		1,643	1,579
Net liability for future policy benefits after reinsurance recoverable		9,829	9,126
Life insurance | Aflac Japan
Present value of expected premiums:
Beginning balance		7,485	10,847
Beginning balance at original discount rate		7,284	10,064
Effect of changes in cash flow assumptions			0	(494)
Effect of actual variances from expected experience			(14)	(81)
Adjusted beginning of period balance			7,270	9,489
Issuances		111	221
Interest accrual		33	146
Net premium earned	[1]	(286)	(1,229)
Foreign currency translation		(44)	(1,343)
Other		0	0
Ending balance at original discount rate		7,084	7,284	10,064
Effect of change in discount rate assumptions		319	201
Ending balance		7,403	7,485	10,847
Present value of expected future policy benefits:
Beginning balance		31,954	42,720
Beginning balance at original discount rate		32,800	39,002
Effect of changes in cash flow assumptions			0	(550)
Effect of actual variances from expected experience			(14)	(91)
Adjusted beginning of period balance			32,786	38,361
Issuances		112	222
Interest accrual		166	670
Benefit payments		(493)	(1,248)
Foreign currency translation		(201)	(5,205)
Other		0	0
Ending balance at original discount rate		32,370	32,800	39,002
Effect of change in discount rate assumptions		344	(846)
Ending balance		32,714	31,954	42,720
Net liability for future policy benefits		25,311	24,469
Less: reinsurance		0	0
Net liability for future policy benefits after reinsurance recoverable		25,311	24,469
Life insurance | Aflac U.S.
Present value of expected premiums:
Beginning balance		724	834
Beginning balance at original discount rate		799	780
Effect of changes in cash flow assumptions			0	(1)
Effect of actual variances from expected experience			(4)	(16)
Adjusted beginning of period balance			795	763
Issuances		49	146
Interest accrual		7	27
Net premium earned	[1]	(33)	(131)
Foreign currency translation		0	0
Other		4	(6)
Ending balance at original discount rate		822	799	780
Effect of change in discount rate assumptions		(60)	(75)
Ending balance		762	724	834
Present value of expected future policy benefits:
Beginning balance		1,526	1,843
Beginning balance at original discount rate		1,778	1,694
Effect of changes in cash flow assumptions			0	(1)
Effect of actual variances from expected experience			(6)	(21)
Adjusted beginning of period balance			1,772	1,672
Issuances		53	149
Interest accrual		16	62
Benefit payments		(29)	(103)
Foreign currency translation		0	0
Other		4	(2)
Ending balance at original discount rate		1,816	1,778	1,694
Effect of change in discount rate assumptions		(210)	(252)
Ending balance		1,606	1,526	1,843
Net liability for future policy benefits		844	802
Less: reinsurance		10	9
Net liability for future policy benefits after reinsurance recoverable		834	793
Accident | Aflac U.S.
Present value of expected premiums:
Beginning balance		2,534	3,283
Beginning balance at original discount rate		2,760	2,999
Effect of changes in cash flow assumptions			0	(52)
Effect of actual variances from expected experience			(48)	(152)
Adjusted beginning of period balance			2,712	2,795
Issuances		117	355
Interest accrual		25	105
Net premium earned	[1]	(118)	(496)
Foreign currency translation		0	0
Other		0	1
Ending balance at original discount rate		2,736	2,760	2,999
Effect of change in discount rate assumptions		(173)	(226)
Ending balance		2,563	2,534	3,283
Present value of expected future policy benefits:
Beginning balance		3,098	3,949
Beginning balance at original discount rate		3,391	3,594
Effect of changes in cash flow assumptions			0	(70)
Effect of actual variances from expected experience			(55)	(177)
Adjusted beginning of period balance			3,336	3,347
Issuances		124	364
Interest accrual		31	128
Benefit payments		(115)	(456)
Foreign currency translation		0	0
Other		0	8
Ending balance at original discount rate		3,376	3,391	3,594
Effect of change in discount rate assumptions		(227)	(293)
Ending balance		3,149	3,098	3,949
Net liability for future policy benefits		586	564
Less: reinsurance		0	0
Net liability for future policy benefits after reinsurance recoverable		586	564
Disability | Aflac U.S.
Present value of expected premiums:
Beginning balance		1,635	1,862
Beginning balance at original discount rate		1,775	1,760
Effect of changes in cash flow assumptions			0	5
Effect of actual variances from expected experience			(20)	(43)
Adjusted beginning of period balance			1,755	1,722
Issuances		120	384
Interest accrual		15	57
Net premium earned	[1]	(95)	(382)
Foreign currency translation		0	0
Other		0	(6)
Ending balance at original discount rate		1,795	1,775	1,760
Effect of change in discount rate assumptions		(112)	(140)
Ending balance		1,683	1,635	1,862
Present value of expected future policy benefits:
Beginning balance		2,445	2,871
Beginning balance at original discount rate		2,636	2,670
Effect of changes in cash flow assumptions			0	5
Effect of actual variances from expected experience			(24)	(48)
Adjusted beginning of period balance			2,612	2,627
Issuances		127	397
Interest accrual		23	94
Benefit payments		(118)	(483)
Foreign currency translation		0	0
Other		0	1
Ending balance at original discount rate		2,644	2,636	2,670
Effect of change in discount rate assumptions		(149)	(191)
Ending balance		2,495	2,445	2,871
Net liability for future policy benefits		812	810
Less: reinsurance		0	0
Net liability for future policy benefits after reinsurance recoverable		812	810
Critical Care | Aflac U.S.
Present value of expected premiums:
Beginning balance		4,486	6,023
Beginning balance at original discount rate		5,050	5,391
Effect of changes in cash flow assumptions			0	(38)
Effect of actual variances from expected experience			(104)	(421)
Adjusted beginning of period balance			4,946	4,932
Issuances		192	537
Interest accrual		46	193
Net premium earned	[1]	(147)	(612)
Foreign currency translation		0	0
Other		0	0
Ending balance at original discount rate		5,037	5,050	5,391
Effect of change in discount rate assumptions		(444)	(564)
Ending balance		4,593	4,486	6,023
Present value of expected future policy benefits:
Beginning balance		11,489	15,388
Beginning balance at original discount rate		12,846	13,079
Effect of changes in cash flow assumptions			0	(43)
Effect of actual variances from expected experience			(120)	(465)
Adjusted beginning of period balance			12,726	12,571
Issuances		201	550
Interest accrual		133	539
Benefit payments		(224)	(823)
Foreign currency translation		0	0
Other		0	9
Ending balance at original discount rate		12,836	12,846	13,079
Effect of change in discount rate assumptions		(1,019)	(1,357)
Ending balance		11,817	11,489	15,388
Net liability for future policy benefits		7,224	7,003
Less: reinsurance		0	0
Net liability for future policy benefits after reinsurance recoverable		7,224	7,003
Hospital Indemnity | Aflac U.S.
Present value of expected premiums:
Beginning balance		1,220	1,467
Beginning balance at original discount rate		1,365	1,380
Effect of changes in cash flow assumptions			0	42
Effect of actual variances from expected experience			(39)	(111)
Adjusted beginning of period balance			1,326	1,311
Issuances		103	273
Interest accrual		11	45
Net premium earned	[1]	(62)	(261)
Foreign currency translation		0	0
Other		0	(3)
Ending balance at original discount rate		1,378	1,365	1,380
Effect of change in discount rate assumptions		(117)	(145)
Ending balance		1,261	1,220	1,467
Present value of expected future policy benefits:
Beginning balance		2,074	2,552
Beginning balance at original discount rate		2,300	2,300
Effect of changes in cash flow assumptions			0	40
Effect of actual variances from expected experience			(48)	(130)
Adjusted beginning of period balance			2,252	2,210
Issuances		111	282
Interest accrual		21	85
Benefit payments		(69)	(277)
Foreign currency translation		0	0
Other		0	0
Ending balance at original discount rate		2,315	2,300	2,300
Effect of change in discount rate assumptions		(176)	(226)
Ending balance		2,139	2,074	2,552
Net liability for future policy benefits		878	854
Less: reinsurance		0	0
Net liability for future policy benefits after reinsurance recoverable		878	854
Dental/Vision | Aflac U.S.
Present value of expected premiums:
Beginning balance		211	264
Beginning balance at original discount rate		231	241
Effect of changes in cash flow assumptions			0	10
Effect of actual variances from expected experience			(7)	(20)
Adjusted beginning of period balance			224	231
Issuances		10	33
Interest accrual		2	9
Net premium earned	[1]	(10)	(42)
Foreign currency translation		0	0
Other		2	0
Ending balance at original discount rate		228	231	241
Effect of change in discount rate assumptions		(15)	(20)
Ending balance		213	211	264
Present value of expected future policy benefits:
Beginning balance		488	616
Beginning balance at original discount rate		532	549
Effect of changes in cash flow assumptions			0	13
Effect of actual variances from expected experience			(9)	(23)
Adjusted beginning of period balance			523	539
Issuances		12	34
Interest accrual		5	21
Benefit payments		(15)	(62)
Foreign currency translation		0	0
Other		2	0
Ending balance at original discount rate		527	532	549
Effect of change in discount rate assumptions		(33)	(44)
Ending balance		494	488	616
Net liability for future policy benefits		281	277
Less: reinsurance		0	0
Net liability for future policy benefits after reinsurance recoverable		281	277
Other | Aflac Japan
Present value of expected premiums:
Beginning balance		1,256	1,586
Beginning balance at original discount rate		1,242	1,461
Effect of changes in cash flow assumptions			0	25
Effect of actual variances from expected experience			(2)	(10)
Adjusted beginning of period balance			1,240	1,476
Issuances		8	62
Interest accrual		5	22
Net premium earned	[1]	(31)	(123)
Foreign currency translation		(8)	(195)
Other		0	0
Ending balance at original discount rate		1,214	1,242	1,461
Effect of change in discount rate assumptions		42	14
Ending balance		1,256	1,256	1,586
Present value of expected future policy benefits:
Beginning balance		5,582	7,322
Beginning balance at original discount rate		5,940	6,787
Effect of changes in cash flow assumptions			0	96
Effect of actual variances from expected experience			0	(10)
Adjusted beginning of period balance			5,940	6,873
Issuances		9	68
Interest accrual		27	106
Benefit payments		(61)	(202)
Foreign currency translation		(35)	(905)
Other		0	0
Ending balance at original discount rate		5,880	5,940	6,787
Effect of change in discount rate assumptions		(110)	(358)
Ending balance		5,770	5,582	7,322
Net liability for future policy benefits		4,514	4,326
Less: reinsurance		0	0
Net liability for future policy benefits after reinsurance recoverable		4,514	4,326
Other | Aflac U.S.
Present value of expected premiums:
Beginning balance		110	153
Beginning balance at original discount rate		118	135
Effect of changes in cash flow assumptions			0	(12)
Effect of actual variances from expected experience			(1)	6
Adjusted beginning of period balance			117	129
Issuances		14	0
Interest accrual		1	5
Net premium earned	[1]	(4)	(17)
Foreign currency translation		0	0
Other		9	1
Ending balance at original discount rate		137	118	135
Effect of change in discount rate assumptions		(6)	(8)
Ending balance		131	110	153
Present value of expected future policy benefits:
Beginning balance		622	837
Beginning balance at original discount rate		624	645
Effect of changes in cash flow assumptions			0	(15)
Effect of actual variances from expected experience			(2)	7
Adjusted beginning of period balance			622	637
Issuances		13	0
Interest accrual		8	32
Benefit payments		(11)	(45)
Foreign currency translation		0	0
Other		9	0
Ending balance at original discount rate		641	624	645
Effect of change in discount rate assumptions		15	(2)
Ending balance		656	622	$ 837
Net liability for future policy benefits		525	512
Less: reinsurance		0	0
Net liability for future policy benefits after reinsurance recoverable		$ 525	$ 512

[1] Net premiums earned represent the portion of gross premiums collected from policyholders that is used to fund expected benefit payments.