Financial Condition and Net Income on a Statutory Basis - Significant Subsidiaries (Reconciliation of NAIC SAP and Prescribed Practice) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Statutory Basis [Abstract]
Prescribed Practice Surplus Note	$ 515,399rga_PrescribedPracticeSurplusNote	$ 343,780rga_PrescribedPracticeSurplusNote
Prescribed Practice Letters Of Credit	(642,200)rga_PrescribedPracticeLettersOfCredit	(436,200)rga_PrescribedPracticeLettersOfCredit
Surplus Deficit NAIC SAP	$ (126,801)rga_SurplusDeficitNaicSap	$ (92,420)rga_SurplusDeficitNaicSap

Represents surplus of the reporting company, including accrued surplus note interest that is reported as a reduction in surplus under prescribed practices but not under NAIC SAP.

No definition available.

Name:	rga_PrescribedPracticeSurplusNote
Namespace Prefix:	rga_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant