Equity Equity (Stock Repurchases) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended	114 Months Ended
	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Equity, Class of Treasury Stock [Line Items]
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 264	$ 264
Treasury Stock, Shares	153,891,260	153,891,260	154,905,595
Acquisition of treasury stock (shares)	0	154,300,000
Treasury Stock Acquired, Average Cost Per Share		$ 12.12
Treasury Stock, Value, Acquired, Cost Method		$ 1,900