Investments (Schedule Of Average Carrying Value Of Impaired Mortgage Loans On Real Estate) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
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	1
Interest income collected on impaired commercial mortgage loans on real estate	$ 1

Interest income recognized on impaired mortgage loans on real estate.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration