STATUTORY ACCOUNTING AND DIVIDEND RESTRICTIONS - Additional Information (Detail)			12 Months Ended							1 Months Ended
	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2013 Aflac USD ($)	Dec. 31, 2012 Aflac USD ($)	Dec. 31, 2011 Aflac USD ($)	Dec. 31, 2013 Aflac Separate Account Funding Agreements USD ($)	Dec. 31, 2012 Aflac Separate Account Funding Agreements USD ($)	Dec. 31, 2013 Aflac Japan USD ($)	Dec. 31, 2012 Aflac Japan USD ($)	Jul. 31, 2013 2013 profit repatriation USD ($)	Jul. 31, 2013 Foreign currency forwards and options 2013 profit repatriation JPY (¥)	Dec. 31, 2013 Foreign currency forwards and options 2014 profit repatriation JPY (¥)	Jan. 31, 2014 Subsequent Event Foreign currency forwards 2014 profit repatriation JPY (¥)
Statutory Accounting Practices [Line Items]
Guaranteed separate account funding agreements, unrealized gain (loss)						$ 35,000,000	$ 46,000,000
Statutory Accounting Practices, Statutory Capital and Surplus Required	1,300,000,000
Net Income, Nebraska state basis			2,400,000,000	2,300,000,000	444,000,000
Capital and surplus, statutory accounting practices of the state or country basis			9,630,000,000	8,892,000,000				4,200,000,000	3,900,000,000
Amount available for dividend distribution without prior approval from regulatory agency			2,400,000,000
Dividends declared			962,000,000
Net Derivatives Notional Amount	22,475,000,000	13,370,000,000									65,000,000,000	47,500,000,000
Foreign Currency Transaction Gain (Loss), before Tax										24,000,000
Derivative notional amount, restructured hedging strategy													¥ 52,500,000,000