Reinsurance (Earned Life Insurance Premiums On Ceded Business) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Direct premiums earned	$ 5,681	$ 5,251	$ 5,052
Ceded earned premiums	(276)	(230)	(230)
Life Insurance Segment
Direct premiums earned	341	320	300
Ceded earned premiums	(71)	(70)	(68)
Net earned premiums	270	250	232
Ceded contract holders' benefits incurred	359	328	319
Ceded contract holders' benefits incurred	(73)	(61)	(67)
Contract holders' benefits incurred	$ 286	$ 267	$ 252

Amount of earned premiums ceded to other entities.

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