Investments (Changes In Allowance For Credit Losses On AFS) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Line Items]
Balance as of beginning-of-period	$ 19.0
Balance as of end-of-period	22.0	$ 19.0
Fixed Maturity AFS Securities [Member]
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Line Items]
Balance as of beginning-of-period	19.0	13.0
Additions for securities for which credit losses were not previously recognized	8.0	9.0	$ 45.0
Additions (reductions) for securities for which credit losses were previously recognized	9.0	5.0	(2.0)
Reductions for securities disposed	(2.0)	(2.0)	(17.0)
Reductions for securities charged-off	(12.0)	(6.0)	(13.0)
Balance as of end-of-period	22.0	19.0	13.0
Accrued interest receivable on fixed maturity AFS securities	1,100.0	972.0	1,000.0
Fixed Maturity AFS Securities [Member] \| Corporate Bonds [Member]
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Line Items]
Balance as of beginning-of-period	17.0	12.0
Additions for securities for which credit losses were not previously recognized	4.0	8.0	43.0
Additions (reductions) for securities for which credit losses were previously recognized	2.0	5.0	(1.0)
Reductions for securities disposed	(2.0)	(2.0)	(17.0)
Reductions for securities charged-off	(12.0)	(6.0)	(13.0)
Balance as of end-of-period	9.0	17.0	12.0
Fixed Maturity AFS Securities [Member] \| RMBS [Member]
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Line Items]
Balance as of beginning-of-period	1.0	1.0
Additions for securities for which credit losses were not previously recognized	3.0		1.0
Additions (reductions) for securities for which credit losses were previously recognized	3.0
Balance as of end-of-period	7.0	1.0	1.0
Fixed Maturity AFS Securities [Member] \| ABS [Member]
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Line Items]
Balance as of end-of-period	5.0
Fixed Maturity AFS Securities [Member] \| Other [Member]
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Line Items]
Balance as of beginning-of-period	1.0
Additions for securities for which credit losses were not previously recognized	1.0	1.0	1.0
Additions (reductions) for securities for which credit losses were previously recognized	4.0		$ (1.0)
Balance as of end-of-period	$ 6.0	$ 1.0

Amount of writeoff of accrued interest on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized by reversing interest income.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 3D
-URI https://asc.fasb.org/extlink&oid=124269663&loc=SL120267862-210455

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Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=124269663&loc=SL82922900-210455

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 9
-Subparagraph (i)
-URI https://asc.fasb.org/extlink&oid=124269663&loc=SL82922900-210455

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
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-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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