Derivative Instruments And Hedging Activities (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Derivative Instruments, Gain Reclassified from Accumulated OCI into Income, Effective Portion	$ 5,000,000
Derivatives designated for hedges of investments in foreign operations	0
Fair values of derivative assets reduced (increased) by net credit valuation adjustments	3,000,000	$ 2,000,000
Notional amount of bank and insurance trust preferred CDOs	7,481,000,000	6,824,000,000
Cash collateral pledged for derivative liabilities	45,000,000
Derivative Credit Risk Valuation Adjustment, Derivative Liabilities	1,000,000	1,000,000
Other Liabilities [Member]
Derivative [Line Items]
Derivative Liability, Fair Value, Gross Liability	39,000,000	40,000,000
Other Liabilities [Member] | Derivative Financial Instruments, Liabilities [Member]
Derivative [Line Items]
Gross amounts recognized	$ 39,000,000	$ 40,000,000