BUSINESS SEGMENT AND SELECTED FOREIGN CURRENCY TRANSLATION ITEMS - Information on Transfers of Funds from Aflac Japan (Detail) $ in Millions, ¥ in Billions	12 Months Ended
	Dec. 31, 2024 USD ($)	Dec. 31, 2024 JPY (¥)	Dec. 31, 2023 USD ($)	Dec. 31, 2023 JPY (¥)	Dec. 31, 2022 USD ($)	Dec. 31, 2022 JPY (¥)
Segment Reporting [Abstract]
Management fees	$ 69		$ 67		$ 61
Profit remittances	2,865	¥ 441.6	2,623	¥ 374.7	2,412	¥ 324.2
Total transfers from Aflac Japan	$ 2,934		$ 2,690		$ 2,473