Schedule II - Aflac Incorporated - Aggregate Contractual Maturities of Notes Payable (Detail) $ in Millions	Dec. 31, 2019 USD ($)
Condensed Financial Statements, Captions [Line Items]
2020	$ 0
2021	0
2022	350
2023	700
2024	750
Thereafter	4,658
Total	6,458
Parent Company
Condensed Financial Statements, Captions [Line Items]
2020	0
2021	0
2022	350
2023	700
2024	750
Thereafter	4,386
Total	$ 6,186

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04.(a))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

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-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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