Document and Entity Information Document Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Jan. 31, 2022	Jun. 30, 2021
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, 2021
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
Entity filer category	Large Accelerated Filer
Entity well known seasoned issuer	Yes
Entity public float			$ 7,800
Document Fiscal Year Focus	2021
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
ICFR Auditor Attestation Flag	true
Common Shares Outstanding		67,189,921
Auditor Name	DELOITTE & TOUCHE LLP
Auditor Location	St. Louis, Missouri
Auditor Firm ID	34
Current fiscal year end date	--12-31