BUSINESS SEGMENT AND FOREIGN INFORMATION - Operations by Segment - Assets (Detail) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 157,542	$ 165,086
Aflac Japan
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	128,536	137,271
Aflac U.S.
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	23,106	22,864
Corporate and other
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 5,900	$ 4,951

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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+ Details