STATUTORY ACCOUNTING AND DIVIDEND RESTRICTIONS - Reconciliation of Capital and Surplus Between Sap and Practices Permitted by the State of Nebraska (Detail) (Aflac, USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Statutory Accounting Practices [Line Items]
Capital and surplus, Nebraska state basis	$ 9,630	$ 8,892
Capital and surplus, NAIC basis	9,624	8,889
Refundable lease deposits - Japan
Statutory Accounting Practices [Line Items]
State permitted practice amount	(41)	(49)
Separate Account Funding Agreements
Statutory Accounting Practices [Line Items]
State permitted practice amount	$ 35	$ 46