POLICY LIABILITIES - Liability for Future Policy Benefits (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	$ 69,136	$ 76,463
Percentage of advanced premiums to unearned premiums	82.00%	82.00%
Aflac U.S.
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	5.80%	6.00%	6.00%
Aflac U.S. | Health insurance | 2013
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	124	0
Aflac U.S. | Health insurance | 2012
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	3.75%
Interest Rates In 20 Years	3.75%
Liability amounts	221	127
Aflac U.S. | Health insurance | 2011
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	4.75%
Interest Rates In 20 Years	4.75%
Liability amounts	243	202
Aflac U.S. | Health insurance | 2005-2010
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	5.50%
Interest Rates In 20 Years	5.50%
Liability amounts	2,897	2,775
Aflac U.S. | Health insurance | 1988-2004
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	8.00%
Interest Rates In 20 Years	6.00%
Liability amounts	725	748
Aflac U.S. | Health insurance | 1986-2004
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	6.00%
Interest Rates In 20 Years	6.00%
Liability amounts	1,301	1,317
Aflac U.S. | Health insurance | 1981-1986
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	190	198
Aflac U.S. | Health insurance | 1998-2004
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	7.00%
Interest Rates In 20 Years	7.00%
Liability amounts	1,237	1,200
Aflac U.S. | Health insurance | Other years
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	22	23
Aflac U.S. | Life insurance | 1956-2013
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	396	343
Aflac Japan
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	3.90%	4.00%	4.00%
Aflac Japan | Health insurance | 2002-2013
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	3,370	2,518
Aflac Japan | Health insurance | 1974-2013
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	3,889	4,624
Aflac Japan | Health insurance | 1998-2013
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	3.00%
Interest Rates In 20 Years	3.00%
Liability amounts	11,763	13,685
Aflac Japan | Health insurance | 1997-1999
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	3.50%
Interest Rates In 20 Years	3.50%
Liability amounts	2,842	3,482
Aflac Japan | Health insurance | 1994-1996
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	3,483	4,261
Aflac Japan | Health insurance | 1987-1994
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	5.50%
Interest Rates In 20 Years	5.50%
Liability amounts	16,727	20,635
Aflac Japan | Health insurance | 1985-1991
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	2,262	2,824
Aflac Japan | Health insurance | 1978-1984
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	6.50%
Interest Rates In 20 Years	5.50%
Liability amounts	2,699	3,416
Aflac Japan | Life insurance | 2013
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	59	0
Aflac Japan | Life insurance | 2001-2013
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	3,009	2,238
Aflac Japan | Life insurance | 2011-2013
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	2.00%
Interest Rates In 20 Years	2.00%
Liability amounts	1,584	733
Aflac Japan | Life insurance | 2009-2011
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	2.25%
Interest Rates In 20 Years	2.25%
Liability amounts	1,648	1,374
Aflac Japan | Life insurance | 2005-2011
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	2.50%
Interest Rates In 20 Years	2.50%
Liability amounts	1,211	1,231
Aflac Japan | Life insurance | 1985-2006
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	2.70%
Interest Rates In 20 Years	2.25%
Liability amounts	2,303	2,791
Aflac Japan | Life insurance | 2007-2011
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	2.75%
Interest Rates In 20 Years	2.75%
Liability amounts	1,025	1,049
Aflac Japan | Life insurance | 1999-2011
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	3.00%
Interest Rates In 20 Years	3.00%
Liability amounts	2,164	2,547
Aflac Japan | Life insurance | 1996-2009
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	3.50%
Interest Rates In 20 Years	3.50%
Liability amounts	721	872
Aflac Japan | Life insurance | 1994-1996
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability amounts	$ 1,021	$ 1,250
Health insurance | Aflac U.S. | 2013 | Lower Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	3.00%
Interest Rates In 20 Years	3.00%
Health insurance | Aflac U.S. | 2013 | Upper Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	3.50%
Interest Rates In 20 Years	3.50%
Health insurance | Aflac U.S. | 1981-1986 | Lower Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	6.50%
Interest Rates In 20 Years	5.50%
Health insurance | Aflac U.S. | 1981-1986 | Upper Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	7.00%
Interest Rates In 20 Years	6.50%
Health insurance | Aflac Japan | 2002-2013 | Lower Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	1.25%
Interest Rates In 20 Years	1.25%
Health insurance | Aflac Japan | 2002-2013 | Upper Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	2.50%
Interest Rates In 20 Years	2.50%
Health insurance | Aflac Japan | 1974-2013 | Lower Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	2.70%
Interest Rates In 20 Years	2.25%
Health insurance | Aflac Japan | 1974-2013 | Upper Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	2.75%
Interest Rates In 20 Years	2.75%
Health insurance | Aflac Japan | 1994-1996 | Lower Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	4.00%
Interest Rates In 20 Years	4.00%
Health insurance | Aflac Japan | 1994-1996 | Upper Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	4.50%
Interest Rates In 20 Years	4.50%
Health insurance | Aflac Japan | 1987-1994 | Lower Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	5.25%
Health insurance | Aflac Japan | 1987-1994 | Upper Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	6.75%
Health insurance | Aflac Japan | 1985-1991 | Lower Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates In 20 Years	5.25%
Health insurance | Aflac Japan | 1985-1991 | Upper Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates In 20 Years	5.50%
Life insurance | Aflac U.S. | 1956-2013 | Lower Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	4.00%
Interest Rates In 20 Years	4.00%
Life insurance | Aflac U.S. | 1956-2013 | Upper Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	6.00%
Interest Rates In 20 Years	6.00%
Life insurance | Aflac Japan | 2013 | Lower Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	1.50%
Interest Rates In 20 Years	1.50%
Life insurance | Aflac Japan | 2013 | Upper Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	1.75%
Interest Rates In 20 Years	1.75%
Life insurance | Aflac Japan | 2001-2013 | Lower Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	1.65%
Interest Rates In 20 Years	1.65%
Life insurance | Aflac Japan | 2001-2013 | Upper Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	1.85%
Interest Rates In 20 Years	1.85%
Life insurance | Aflac Japan | 1994-1996 | Lower Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	4.00%
Interest Rates In 20 Years	4.00%
Life insurance | Aflac Japan | 1994-1996 | Upper Limit
Liability for Future Policy Benefit, by Product Segment [Line Items]
Interest Rates Year of Issue	4.50%
Interest Rates In 20 Years	4.50%