INCOME TAXES - Income Tax Effects of Temporary Differences that Gave Rise to Deferred Income Tax Assets and Liabilities (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Deferred income tax liabilities:
Deferred policy acquisition costs	$ 2,484	$ 2,731
Unrealized gains on investment securities	1,034	1,522
Policyholder protection corporation obligation	15	10
Difference in tax basis of investment in Aflac Japan	188	288
Premiums receivable	153	164
Policy benefit reserves	1,859	1,995
Total deferred income tax liabilities	5,733	6,710
Deferred income tax assets:
Depreciation	85	124
Other basis differences in investment securities	1,629	1,471
Unfunded retirement benefits	42	45
Other accrued expenses	65	60
Policy and contract claims	73	67
Unrealized exchange loss on yen-denominated notes payable	41	36
Deferred compensation	149	203
Capital loss carryforwards	502	716
Other	383	438
Total deferred income tax assets	2,969	3,160
Deferred Tax Assets, Net, Noncurrent	(2,764)	(3,550)
Current income tax liability	954	308
Total income tax liability	$ 3,718	$ 3,858