Investments (Composition Of Current And Past Due Mortgage Loans On Real Estate) (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Mortgage Loans On Real Estate Aging [Abstract]
Allowance for credit losses	$ (96,000,000)	$ (204,000,000)
Unamortized premium (discount)	16,000,000	8,000,000
Mark-to-market gains (losses)	(3,000,000)	(5,000,000)
Total carrying value	17,991,000,000	16,763,000,000
Current [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Mortgage loans on real estate, gross	18,004,000,000	16,855,000,000
30 to 59 Days Past Due [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Mortgage loans on real estate, gross	36,000,000	32,000,000
60 to 89 Days Past Due [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Mortgage loans on real estate, gross	5,000,000	8,000,000
90 Or More Days Past Due [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Mortgage loans on real estate, gross	29,000,000	69,000,000
Commercial [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Mortgage loans on real estate, gross	17,171,000,000	16,235,000,000
Allowance for credit losses	(79,000,000)	(187,000,000)
Unamortized premium (discount)	(11,000,000)	(14,000,000)
Mark-to-market gains (losses)	(3,000,000)	(5,000,000)
Total carrying value	17,089,000,000	16,043,000,000
Commercial [Member] \| Current [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Mortgage loans on real estate, gross	17,167,000,000	16,245,000,000
Commercial [Member] \| 30 to 59 Days Past Due [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Mortgage loans on real estate, gross	15,000,000	4,000,000
Residential [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Mortgage loans on real estate, gross	919,000,000	737,000,000
Allowance for credit losses	(17,000,000)	(17,000,000)
Unamortized premium (discount)	27,000,000	22,000,000
Total carrying value	902,000,000	720,000,000
Residential [Member] \| Current [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Mortgage loans on real estate, gross	837,000,000	610,000,000
Residential [Member] \| 30 to 59 Days Past Due [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Mortgage loans on real estate, gross	21,000,000	28,000,000
Residential [Member] \| 60 to 89 Days Past Due [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Mortgage loans on real estate, gross	5,000,000	8,000,000
Residential [Member] \| 90 Or More Days Past Due [Member]
Mortgage Loans On Real Estate Aging [Abstract]
Mortgage loans on real estate, gross	$ 29,000,000	$ 69,000,000

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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.

+ References

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- Definition

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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