Investments (Mortgage Loans by Portfolio Segment) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	$ 81,393	$ 84,344
Allowance for Credit Loss	(563)	(590)	$ (520)	$ (353)
Subtotal mortgage loans, net	$ 80,830	$ 83,754
Percentage Of mortgage total recorded investment To Mortgage Loans On Real Estate Commercial And Consumer Net	100.50%	100.50%
Percentage of Allowance for Credit Losses for Financing Receivables	(0.70%)	(0.70%)
Percentage Of Mortgage Loans Held For Investment Net To Mortgage Loans On Real Estate Commercial And Consumer Net	99.80%	99.80%
Total mortgage loans held-for-investment, net	$ 80,964	$ 83,919
Percentage Of Loans And Leases Receivable Consumer Other To Mortgage Loans On Real Estate Commercial And Consumer Net	0.20%	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]
Total mortgage loans held-for-investment, net	$ 134	$ 165
Commercial Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	51,336	52,434
Allowance for Credit Loss	$ (274)	$ (252)	(211)	(246)
Percentage Of Mortgage Loans, Gross	63.40%	62.50%
Residential Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	$ 11,704	$ 13,782
Allowance for Credit Loss	$ (196)	$ (232)	(218)	(55)
Percentage Of Mortgage Loans, Gross	14.40%	16.40%
Agricultural Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	$ 18,353	$ 18,128
Allowance for Credit Loss	$ (93)	$ (106)	$ (91)	$ (52)
Percentage Of Mortgage Loans, Gross	22.70%	21.60%

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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Percentage Of Allowance for Credit Losses for Financing Receivables

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

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