Long-Term Debt (Schedule Of Subordinated Notes) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Subordinated Borrowing [Line Items]
Subordinated notes	$ 572	$ 87
Subordinated Notes Par Amount	$ 588
Long-term Debt, Interest Rate 6.95%	6.95%
Long-term Debt, Interest Rate 3.25%	3.25%
Subordinated Notes Interest Rate 6.95 Percent [Member]
Subordinated Borrowing [Line Items]
Subordinated notes	$ 87
Subordinated Notes Par Amount	88
Subordinated Notes Interest Rate 3.25 Percent [Member]
Subordinated Borrowing [Line Items]
Subordinated notes	485
Subordinated Notes Par Amount	$ 500