Financial Condition and Net Income on a Statutory Basis - Significant Subsidiaries (Statutory Accounting Practices Disclosure) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
RGA Reinsurance [Member]
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	$ 2,368	$ 2,131
Statutory Accounting Practices, Statutory Net Income Amount	(98)	(133)	$ 280
RGA Canada [Member]
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	903	886
Statutory Accounting Practices, Statutory Net Income Amount	25	152	(225)
RGA Barbados [Member]
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	1,781	1,835
Statutory Accounting Practices, Statutory Net Income Amount	52	268	234
RGA Australia [Member]
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	485	535
Statutory Accounting Practices, Statutory Net Income Amount	(22)	42	15
RGA Atlantic [Member]
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	1,137	1,441
Statutory Accounting Practices, Statutory Net Income Amount	(226)	175	243
RGA International Reinsurance Company dac [Member]
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	1,121	1,460
Statutory Accounting Practices, Statutory Net Income Amount	43	52	37
RGA Americas [Member]
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	6,812	8,249
Statutory Accounting Practices, Statutory Net Income Amount	(241)	879	1,049
Other Reinsurance Subsidiaries [Member]
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	1,015	1,298
Statutory Accounting Practices, Statutory Net Income Amount	(152)	194	114
RGA Reinsurance Company Of Missouri
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	2,362	2,136
Statutory Accounting Practices, Statutory Net Income Amount	(13)	4	75
RGA Worldwide Reinsurance Company
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	702	703
Statutory Accounting Practices, Statutory Net Income Amount	10	104	106
RGA Global Reinsurance Company
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Capital and Surplus, Balance	565	495
Statutory Accounting Practices, Statutory Net Income Amount	$ 93	$ 59	$ 71