Investments (Summary Of Components Of Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Schedule of Available-for-sale Securities [Line Items]
Gross investment income before adjustments	$ 132	$ 208	$ 482	$ 617
Funds held interest income (expense)	1	1	5	7
Interest income from Parent	3	2	7	4
Gross investment income	137	210	494	629
Investment expenses	(13)	(13)	(37)	(36)
Net investment income	124	197	457	593
Fixed Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Gross investment income before adjustments	129	83	339	260
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Gross investment income before adjustments	7	4	15	10
Short-Term Investments and Cash [Member]
Schedule of Available-for-sale Securities [Line Items]
Gross investment income before adjustments	4		4
Limited Partnerships [Member]
Schedule of Available-for-sale Securities [Line Items]
Gross investment income before adjustments	(25)	82	63	260
Dividends From Preferred Shares Of Affiliate [Member]
Schedule of Available-for-sale Securities [Line Items]
Gross investment income before adjustments	8	8	23	23
Other [Member]
Schedule of Available-for-sale Securities [Line Items]
Gross investment income before adjustments	$ 11	$ 31	$ 37	$ 63

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