Schedule II - Aflac Incorporated - Aggregate Contractual Maturities of Notes Payable (Detail) $ in Millions	Dec. 31, 2021 USD ($)
Condensed Financial Statements, Captions [Line Items]
2022	$ 0
2023	0
2024	750
2025	558
2026	743
Thereafter	5,847
Total	7,898
Parent Company
Condensed Financial Statements, Captions [Line Items]
2022	0
2023	0
2024	750
2025	558
2026	743
Thereafter	5,586
Total	$ 7,637

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