Investments (Schedule Of Average Carrying Value Of Impaired Mortgage Loans On Real Estate) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Information about impaired mortgage loans on real estate
Average carrying value for impaired commercial mortgage loans on real estate		$ 5		$ 6
Interest income recognized on impaired commercial mortgage loans on real estate
Interest income collected on impaired commercial mortgage loans on real estate