Investments (Mortgage Loans by Portfolio Segment) (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	$ 84,290	$ 79,860
Allowance for Credit Loss	(527)	(634)	$ (590)	$ (353)
Subtotal mortgage loans, net	83,763	79,226
Mortgage loans (net of allowance for credit loss of $527 and $634, respectively; includes $0 and $127, respectively, under the fair value option)	$ 83,763	$ 79,353
Percentage Of mortgage total recorded investment To Mortgage Loans On Real Estate Commercial And Consumer Net	100.60%	100.60%
Percentage of Allowance for Credit Losses for Financing Receivables	0.60%	0.80%
Percentage Of Mortgage Loans Held For Investment Net To Mortgage Loans On Real Estate Commercial And Consumer Net	100.00%	99.80%
Percentage Of Loans And Leases Receivable Consumer Other To Mortgage Loans On Real Estate Commercial And Consumer Net	0.00%	0.20%
Percentage Of Mortgage Loans On Real Estate To Mortgage Loans On Real Estate Commercial And Consumer Net	100.00%	100.00%
Residential mortgage loans - FVO
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential — FVO	$ 0	$ 127
Mortgage loans (net of allowance for credit loss of $527 and $634, respectively; includes $0 and $127, respectively, under the fair value option)	0	127
Commercial Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	52,502	50,553
Allowance for Credit Loss	$ (218)	$ (340)	(252)	(246)
Percentage Of Mortgage Loans, Gross	62.70%	63.70%
Residential Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	$ 12,482	$ 11,196
Allowance for Credit Loss	$ (190)	$ (206)	(232)	(55)
Percentage Of Mortgage Loans, Gross	14.90%	14.10%
Agricultural Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	$ 19,306	$ 18,111
Allowance for Credit Loss	$ (119)	$ (88)	$ (106)	$ (52)
Percentage Of Mortgage Loans, Gross	23.00%	22.80%

Percentage Of Allowance for Credit Losses for Financing Receivables

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Percentage Of Financing Receivable, Gross

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Percentage of loans and leases receivable consumer other to total mortgage loans on real estate.

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Percentage of Mortgage Loans Held-for-investment, net to total Mortgage Loans on Real Estate.

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Percentage of Mortgage Loans Held For Investment to total Mortgage Loans on Real Estate.

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Percentage of Mortgage Loans On Real Estate to total Mortgage Loans on Real Estate.

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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 after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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