Investments (Composition Of Current And Past Due Mortgage Loans On Real Estate) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Mortgage Loans On Real Estate Aging [Abstract]
Allowance for credit losses	$ (95)	$ (203)	$ (2)
Unamortized premium (discount)	16	8
Mark-to-market gains (losses)	(3)	(5)
Total carrying value	17,893	16,681
Financial Asset Not Past Due [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Carrying amount of mortgages	17,905	16,772
30 to 59 Days Past Due [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Carrying amount of mortgages	36	32
60 to 89 Days Past Due [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Carrying amount of mortgages	5	8
90 Or More Days Past Due [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Carrying amount of mortgages	29	69
Commercial [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Carrying amount of mortgages	17,072	16,152
Allowance for credit losses	(78)	(186)
Unamortized premium (discount)	(11)	(14)
Mark-to-market gains (losses)	(3)	(5)
Total carrying value	16,991	15,961
Commercial [Member] \| Financial Asset Not Past Due [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Carrying amount of mortgages	17,068	16,162
Commercial [Member] \| 30 to 59 Days Past Due [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Carrying amount of mortgages	15	4
Residential [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Carrying amount of mortgages	919	737
Allowance for credit losses	(17)	(17)	$ (2)
Unamortized premium (discount)	27	22
Total carrying value	902	720
Residential [Member] \| Financial Asset Not Past Due [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Carrying amount of mortgages	837	610
Residential [Member] \| 30 to 59 Days Past Due [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Carrying amount of mortgages	21	28
Residential [Member] \| 60 to 89 Days Past Due [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Carrying amount of mortgages	5	8
Residential [Member] \| 90 Or More Days Past Due [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Carrying amount of mortgages	$ 29	$ 69

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- Definition

The amount of premium (net of discount) that was originally recognized at the issuance of the mortgage loan that has yet to be amortized.

+ References

No definition available.

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- Definition

This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of loans and long-term receivables (other than securities categorized as trading, available-for-sale or held-to-maturity) that have contractual principal amounts and for which the fair value option has been elected.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount, before allowance for credit loss, of financing receivable.

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Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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