Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Equity, Class of Treasury Stock [Line Items]
Stock Issued During Period, Shares, New Issues			6,172,840
Entity Listing, Par Value Per Share			$ 0.01
Shares Issued, Price Per Share	$ 81.00		$ 81.00
Document Period End Date			Jun. 30, 2020
Treasury Stock, Value, Acquired, Cost Method	$ (6)	$ (19)	$ (162)	$ (68)
Stock Repurchase Program, Authorized Amount	400		400
Proceeds from Issuance of Common Stock	$ 481		$ 481	$ 0
Underwriter Option Additional Shares			925,926
RGA Share Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Treasury Stock, Shares, Acquired			1,074,413	344,237
Treasury Stock, Value, Acquired, Cost Method			$ 153	$ 50