Investments (Narrative) (Details) $ in Millions	9 Months Ended	12 Months Ended	21 Months Ended
Sep. 30, 2022 USD ($) loan item	Dec. 31, 2021 USD ($) loan item	Sep. 30, 2022 USD ($) loan item
Schedule of Investments [Line Items]
Decrease in gross AFS securities unrealized gains (losses)	$ 13,400
Number of partnerships in alternative investment portfolio \| item	323	305	323
Alternative investments as a percentage of overall invested assets	2.00%	2.00%
Fair value of collateral received that we are permitted to sell or re-pledge	$ 25		$ 25
Investment commitments	2,700		2,700
Investment commitments for limited partnerships	1,600		1,600
Investment commitments for private placements	339		339
Investment commitments for mortgage loans on real estate	$ 690		$ 690
Minimum [Member]
Schedule of Investments [Line Items]
Percentage of the fair value of securities obtained as collateral under reverse repurchase agreements.	80.00%		80.00%
Maximum [Member]
Schedule of Investments [Line Items]
Percentage of the fair value of securities obtained as collateral under reverse repurchase agreements.	95.00%		95.00%
Financial Service [Member] \| Investments [Member]
Schedule of Investments [Line Items]
Fair value	$ 18,900	$ 21,700	$ 18,900
Consumer Non-Cyclical Industry [Member] \| Investments [Member]
Schedule of Investments [Line Items]
Fair value	$ 14,100	$ 18,600	$ 14,100
Mortgage Loans On Real Estate [Member] \| Geographic Concentration [Member] \| Commercial [Member] \| California [Member]
Schedule of Investments [Line Items]
Concentration risk, percentage	27.00%	26.00%
Mortgage Loans On Real Estate [Member] \| Geographic Concentration [Member] \| Commercial [Member] \| Texas [Member]
Schedule of Investments [Line Items]
Concentration risk, percentage			9.00%
Mortgage Loans On Real Estate [Member] \| Geographic Concentration [Member] \| Residential [Member] \| California [Member]
Schedule of Investments [Line Items]
Concentration risk, percentage	18.00%	22.00%
Mortgage Loans On Real Estate [Member] \| Geographic Concentration [Member] \| Residential [Member] \| Florida [Member]
Schedule of Investments [Line Items]
Concentration risk, percentage		14.00%
Mortgage Loans On Real Estate [Member] \| Geographic Concentration [Member] \| Residential [Member] \| NEW JERSEY
Schedule of Investments [Line Items]
Concentration risk, percentage	11.00%
Corporate Bonds [Member]
Schedule of Investments [Line Items]
Percentage of fair value rated as investment grade	96.00%	96.00%	96.00%
Amortized cost of portfolio rated below investment grade	$ 3,600	$ 3,500	$ 3,600
Fair value of portfolio rated below investment grade	3,300	3,700	3,300
Mortgage Loans On Real Estate [Member] \| Commercial [Member]
Schedule of Investments [Line Items]
Impaired financing receivable, principal balance	$ 1	$ 1	$ 1
Mortgage Loans On Real Estate [Member] \| Residential [Member]
Schedule of Investments [Line Items]
Number of loans past due \| loan	64	65	64
Financing Receivable, Number of Loans In Foreclosure \| loan	42	34	42
Financing Receivable, 90 Days or More Past Due, Still Accruing	$ 19	$ 15	$ 19
Number of impaired loans \| loan	36	50	36
Impaired financing receivable, principal balance	$ 14	$ 22	$ 14
Fixed Maturity AFS Securities [Member] \| Federal Home Loan Mortgage Corporation [Member] \| Investments [Member]
Schedule of Investments [Line Items]
Fair value	$ 995	$ 910	995
Concentration risk, percentage	1.00%	1.00%
Fixed Maturity AFS Securities [Member] \| White Chapel LLC [Member] \| Investments [Member]
Schedule of Investments [Line Items]
Fair value	$ 1,000	$ 709	$ 1,000
Concentration risk, percentage	1.00%	1.00%
Fixed Maturity AFS Securities [Member] \| Financial Service [Member] \| Investments [Member]
Schedule of Investments [Line Items]
Concentration risk, percentage	15.00%	14.00%
Fixed Maturity AFS Securities [Member] \| Consumer Non-Cyclical Industry [Member] \| Investments [Member]
Schedule of Investments [Line Items]
Concentration risk, percentage	11.00%	12.00%

Alternative investments as a percentage of overall invested assets.

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Amortized cost of portfolio rated below investment grade.

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This item represents the change in gross unrealized holding gain or loss on available-for-sale securities that has been included in accumulated other comprehensive income, a separate component of shareholders' equity, during the period.

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Percentage of the fair value of portfolio that was rated investment grade as of balance sheet date.

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This item represents the percentage of the fair value of securities obtained as collateral under reverse repurchase agreements

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Fair value of portfolio rated below investment grade.

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Financing Receivable, Number of Loans In Foreclosure

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Financing receivable, Number of loans past due

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This item represents total investment commitments as of the balance sheet date for fixed maturity available-for-sale securities, limited partnerships, real estate and mortgage loans on real estate.

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This item represents investment commitments as of the balance sheet date for mortgage loans.

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Number of partnerships represented in alternative investment portfolio.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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This item represents disclosure of all significant concentrations of credit risk or market risk arising from the subject financial instrument (as defined), whether from an individual counterparty or groups of counterparties.

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Fair value of collateral permitted, by contact or custom, to be sold or re-pledged.

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Amortized cost of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease.

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Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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