BUSINESS SEGMENT INFORMATION - Operations by Segment - Assets (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Segment Reporting [Line Items]
Assets	$ 113,511	$ 116,470
Aflac Japan
Segment Reporting [Line Items]
Assets	87,598	88,537
Aflac U.S.
Segment Reporting [Line Items]
Assets	21,927	22,317
Corporate and other
Segment Reporting [Line Items]
Assets	$ 3,986	$ 5,616

Amount of asset recognized for present right to economic benefit.

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+ Details

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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+ Details