XML 52 R60.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

INVESTMENTS - Net Effect on Shareholders' Equity of Unrealized Gains and Losses from Investment Securities (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Investments [Abstract] |  |
Unrealized gains (losses) on securities available for sale | $ 11,891 | $ 6,039
Deferred income taxes | (3,343) | (1,805)
Shareholders' equity, unrealized gains (losses) on investment securities | $ 8,548 | $ 4,234

X
- Definition Accumulated other comprehensive income loss, deferred income tax on investment securities. + References No definition available. + Details
Name: | afl_AccumulatedOtherComprehensiveIncomeLossDeferredIncomeTaxOnInvestmentSecurities
Namespace Prefix: | afl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount, after tax, of accumulated unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e681-108580 + Details
Name: | us-gaap_AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References No definition available. + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleUnrealizedGainLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_InvestmentsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration