XML 14 R1.htm IDEA: XBRL DOCUMENT v3.10.0.1
Document and Entity Information - shares
 6 Months Ended
Jun. 30, 2018
Jul. 31, 2018
Document And Entitiy Information [Abstract]    
Document Type 10-Q  
Document period end date Jun. 30, 2018  
Amendment flag false  
Entity registrant name REINSURANCE GROUP OF AMERICA INC  
Entity central index key 0000898174  
Entity current reporting status Yes  
Entity voluntary filers No  
Current fiscal year end date --12-31  
Entity filer category Large Accelerated Filer  
Entity well-known seasoned issuer Yes  
Common Shares Outstanding   63,656,444
Document Fiscal Year Focus 2018  
Document Fiscal Period Focus Q2