Financial Condition and Net Income on a Statutory Basis - Significant Subsidiaries (Statutory Accounting Practices Disclosure) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
RGA Reinsurance [Member]
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	$ 2,262	$ 2,368
Statutory Accounting Practices, Statutory Net Income Amount	(332)	(98)	$ (133)
RGA Canada [Member]
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	938	903
Statutory Accounting Practices, Statutory Net Income Amount	108	25	152
RGA Barbados [Member]
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	1,074	1,781
Statutory Accounting Practices, Statutory Net Income Amount	(353)	52	268
RGA Australia [Member]
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	387	485
Statutory Accounting Practices, Statutory Net Income Amount	(68)	(22)	42
RGA Atlantic [Member]
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	759	1,137
Statutory Accounting Practices, Statutory Net Income Amount	36	(226)	175
RGA International Reinsurance Company dac [Member]
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	214	1,121
Statutory Accounting Practices, Statutory Net Income Amount	31	43	52
RGA Americas [Member]
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	1,607	6,812
Statutory Accounting Practices, Statutory Net Income Amount	(441)	(241)	879
Other Reinsurance Subsidiaries [Member]
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	1,038	1,015
Statutory Accounting Practices, Statutory Net Income Amount	300	(152)	194
RGA Worldwide Reinsurance Company
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	639	702
Statutory Accounting Practices, Statutory Net Income Amount	8	10	104
RGA Global Reinsurance Company
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	382	565
Statutory Accounting Practices, Statutory Net Income Amount	0	93	59
RGA Life and Annuity Insurance Company
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	2,516	2,362
Statutory Accounting Practices, Statutory Net Income Amount	$ 5	$ (13)	$ 4