Investments (Mortgage Loans by Portfolio Segment) (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	$ 83,394	$ 84,344
Allowance for Credit Loss	(528)	(590)
Subtotal mortgage loans, net	82,866	83,754
Residential mortgage loans — FVO	$ 83,015	$ 83,919
Percentage Of mortgage total recorded investment To Mortgage Loans On Real Estate Commercial And Consumer Net	100.40%	100.50%
Percentage of Allowance for Credit Losses for Financing Receivables	(0.60%)	(0.70%)
Percentage Of Mortgage Loans Held For Investment Net To Mortgage Loans On Real Estate Commercial And Consumer Net	99.80%	99.80%
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]
Residential mortgage loans — FVO	$ 149	$ 165
Commercial Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	$ 52,300	$ 52,434
Percentage Of Mortgage Loans, Gross	63.00%	62.50%
Residential Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	$ 13,043	$ 13,782
Percentage Of Mortgage Loans, Gross	15.70%	16.40%
Agricultural Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	$ 18,051	$ 18,128
Percentage Of Mortgage Loans, Gross	21.70%	21.60%

Percentage Of Financing Receivable, Gross

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- Definition

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

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- Definition

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

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