INVESTMENTS - Securities Lending (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Investments [Abstract]
Securities loaned total	$ 2,558afl_SecuritiesLoanedTotal	$ 2,149afl_SecuritiesLoanedTotal
Securities loaned collateral obligation to return cash	$ 2,615	$ 2,193

Amount of obligation to return cash collateral under master netting arrangements that has not been offset against securities loaned.

No definition available.

Name:	afl_SecuritiesLoanedCollateralObligationToReturnCash
Namespace Prefix:	afl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant