Fair Value (Schedule Of Realized Gains (Losses) Using Level 3 Inputs) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other Assets, Fair Value Disclosure	$ 95		$ 91
Other Liabilities, Fair Value Disclosure	95		$ 91
Level 3 Equity Securities Gains (Losses), Net [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Realized gains (losses) from Level 3 inputs	$ 3	$ 0