INVESTMENTS - Securities Lending (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Investments [Abstract]
Securities loaned total	$ 2,149afl_SecuritiesLoanedTotal	$ 5,656afl_SecuritiesLoanedTotal
Cash collateral on loaned securities	$ 2,193	$ 5,820

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