Equity (Narrative) (Details) - USD ($) shares in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Class of Stock [Line Items]
Cost of Treasury Stock Acquired	$ 485,000,000	$ 484,000,000
Under December 2018 Board Of Directors Authorization
Class of Stock [Line Items]
Amount of Stock Repurchases Authorized by the Board of Directors			$ 2,000,000,000.0
Under December 2018 Board Of Directors Authorization | Common Stock
Class of Stock [Line Items]
Number of Treasury Stock Shares Acquired	6.7
Cost of Treasury Stock Acquired	$ 500,000,000