Equity (Common Stock Repurchase Authorization) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Aug. 04, 2021	Dec. 11, 2020	Jul. 31, 2019
Equity, Class of Treasury Stock [Line Items]
Stock Repurchase Program, Authorized Amount		$ 3,000	$ 3,000	$ 2,000
July2019Authorization [Member]
Equity, Class of Treasury Stock [Line Items]
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 0
December2020Authorization
Equity, Class of Treasury Stock [Line Items]
Stock Repurchase Program, Remaining Authorized Repurchase Amount	0
August2021Authorization
Equity, Class of Treasury Stock [Line Items]
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 2,708