XML 64 R47.htm IDEA: XBRL DOCUMENT v3.8.0.1
BUSINESS SEGMENT AND FOREIGN INFORMATION - Additional Information (Details)
$ in Millions
12 Months Ended
Dec. 31, 2017
USD ($)
segment
Dec. 31, 2016
USD ($)
Segment Reporting Information [Line Items]    
Reportable insurance business segments | segment 2  
Total receivables related to Aflac Japan's operations $ 827 $ 669
Aflac Japan    
Segment Reporting Information [Line Items]    
Total receivables related to Aflac Japan's operations $ 334 $ 207
Percentage of total receivables related to Aflac Japan's operations 40.40% 30.90%
Maximum | Machinery and equipment    
Segment Reporting Information [Line Items]    
Property, Plant and Equipment, Useful Life 20 years  
Maximum | Building    
Segment Reporting Information [Line Items]    
Property, Plant and Equipment, Useful Life 50 years  
Maximum | Furniture and fixtures    
Segment Reporting Information [Line Items]    
Property, Plant and Equipment, Useful Life 20 years