SUBSEQUENT EVENTS - Additional Information (Details) - Aflac Life Insurance Japan (ALIJ) - Aflac Re Bermuda ¥ in Billions, $ in Billions	1 Months Ended	3 Months Ended
Jan. 31, 2023 USD ($)	Dec. 31, 2023 JPY (¥)
Subsequent Event [Line Items]
Ceded reinsurance, percentage	28.00%
Ceded reinsurance, amount of reserves transferred \| $	$ 2.1
Subsequent Event
Subsequent Event [Line Items]
Ceded reinsurance, percentage		30.00%
Ceded reinsurance, amount of reserves transferred \| ¥		¥ 286

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481674/830-30-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483399/855-10-50-2

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Balance Type:	na
Period Type:	duration