INVESTMENTS - Commercial Mortgage Loans by Key Credit Quality Indicators (Details) $ in Millions	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
Total Financing Receivable	$ 13,223	$ 11,960
Commercial mortgage loans
Financing Receivable, Credit Quality Indicator [Line Items]
2022	54
2021	333
2020	46
2019	602
2018	153
Prior	688
Total Financing Receivable	$ 1,876
Weighted Average Debt Service Coverage Ratio	2.43
Commercial mortgage loans \| 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average Debt Service Coverage Ratio	0.00
Commercial mortgage loans \| 2021
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average Debt Service Coverage Ratio	2.84
Commercial mortgage loans \| 2020
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average Debt Service Coverage Ratio	1.94
Commercial mortgage loans \| 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average Debt Service Coverage Ratio	2.55
Commercial mortgage loans \| 2018
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average Debt Service Coverage Ratio	2.08
Commercial mortgage loans \| Prior
Financing Receivable, Credit Quality Indicator [Line Items]
Weighted Average Debt Service Coverage Ratio	2.25
Commercial mortgage loans \| Loan to Value Ratio, 0.00% to 59.99%
Financing Receivable, Credit Quality Indicator [Line Items]
2022	$ 54
2021	299
2020	46
2019	516
2018	153
Prior	586
Total Financing Receivable	$ 1,654
Weighted Average Debt Service Coverage Ratio	2.52
Commercial mortgage loans \| Loan to Value Ratio, 60.00% to 69.99%
Financing Receivable, Credit Quality Indicator [Line Items]
2022	$ 0
2021	34
2020	0
2019	46
2018	0
Prior	77
Total Financing Receivable	$ 157
Weighted Average Debt Service Coverage Ratio	2.08
Commercial mortgage loans \| Loan to Value Ratio, 70.00% to 79.99%
Financing Receivable, Credit Quality Indicator [Line Items]
2022	$ 0
2021	0
2020	0
2019	40
2018	0
Prior	25
Total Financing Receivable	$ 65
Weighted Average Debt Service Coverage Ratio	1.18
Commercial mortgage loans \| Loan-to-Value Ratio, 80.00% or greater
Financing Receivable, Credit Quality Indicator [Line Items]
2022	$ 0
2021	0
2020	0
2019	0
2018	0
Prior	0
Total Financing Receivable	$ 0
Weighted Average Debt Service Coverage Ratio	0.00

Weighted Average Debt Service Coverage Ratio

No definition available.

Name:	afl_WeightedAverageDebtServiceCoverageRatio
Namespace Prefix:	afl_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Definition

Amortized cost of financing receivable originated more than five years prior to current fiscal year. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 55
-Paragraph 79
-URI https://asc.fasb.org/extlink&oid=124267575&loc=SL82922352-210448

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 6
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919232-210447

+ Details

Name:	us-gaap_FinancingReceivableOriginatedFiveOrMoreYearsBeforeLatestFiscalYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amortized cost of financing receivable originated four years prior to current fiscal year. Excludes net investment in lease.

+ References

+ Details

Name:	us-gaap_FinancingReceivableOriginatedFourYearsBeforeLatestFiscalYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amortized cost of financing receivable originated in current fiscal year. Excludes net investment in lease.

+ References

+ Details

Name:	us-gaap_FinancingReceivableOriginatedInCurrentFiscalYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amortized cost of financing receivable originated in fiscal year prior to current fiscal year. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 6
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919232-210447

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 55
-Paragraph 79
-URI https://asc.fasb.org/extlink&oid=124267575&loc=SL82922352-210448

+ Details

Name:	us-gaap_FinancingReceivableOriginatedInFiscalYearBeforeLatestFiscalYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amortized cost of financing receivable originated three years prior to current fiscal year. Excludes net investment in lease.

+ References

+ Details

Name:	us-gaap_FinancingReceivableOriginatedThreeYearsBeforeLatestFiscalYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amortized cost of financing receivable originated two years prior to current fiscal year. Excludes net investment in lease.

+ References

+ Details

Name:	us-gaap_FinancingReceivableOriginatedTwoYearsBeforeLatestFiscalYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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

No definition available.

+ Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953401-111524

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 55
-Paragraph 79
-URI https://asc.fasb.org/extlink&oid=124267575&loc=SL82922352-210448

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3)(b))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 14
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919253-210447

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919230-210447

Reference 7: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 55
-Paragraph 80
-URI https://asc.fasb.org/extlink&oid=124267575&loc=SL82922355-210448

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (1)

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (2)

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1404
-Paragraph (a)

+ Details

Name:	us-gaap_NotesReceivableGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=afl_CommercialmortgageloansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	afl_YearofOriginationAxis=afl_CurrentFiscalYearMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	afl_YearofOriginationAxis=afl_OriginatedinFiscalYearbeforeLatestFiscalYearMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	afl_YearofOriginationAxis=afl_OriginatedTwoYearsbeforeLatestFiscalYearMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	afl_YearofOriginationAxis=afl_OriginatedThreeYearsbeforeLatestFiscalYearMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	afl_YearofOriginationAxis=afl_OriginatedFourYearsbeforeLatestFiscalYearMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	afl_YearofOriginationAxis=afl_OriginatedFiveorMoreYearsbeforeLatestFiscalYearMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LoanToValueAxis=afl_LoantoValueRatioZerotoFiftyninePointNineninePercentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LoanToValueAxis=afl_LoantoValueRatioSixtytoSixtyninePointNineNinePercentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LoanToValueAxis=afl_LoantoValueRatioSeventytoSeventyninePointNineninePercentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LoanToValueAxis=afl_LoantoValueRatioEightyPercentandAboveMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: