Document and Entity Information Document Information - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2019	Jan. 31, 2020	Jun. 30, 2019
Document And Entitiy Information [Abstract]
Entity Incorporation, State or Country Code	MO
Document type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2019
Amendment flag	false
Entity registrant name	REINSURANCE GROUP OF AMERICA, INCORPORATED
Entity central index key	0000898174
Entity current reporting status	Yes
Entity Interactive Data Current	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		62,583,958
Entity public float			$ 9.8
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Document Transition Report	false
Entity File Number	1-11848
Entity Tax Identification Number	43-1627032