Investments (Mortgage Loans by Portfolio Segment) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	$ 81,628	$ 80,635
Allowance for Credit Loss	464	353
Subtotal mortgage loans, net	81,164	80,282
Mortgage Loans on Real Estate, Commercial and Consumer, Net	81,344	80,529
Total mortgage loans held-for-investment, net	81,344	80,470
Mortgage loans held-for-sale	$ 0	$ 59
Percentage Of mortgage total recorded investment To Mortgage Loans On Real Estate Commercial And Consumer Net	100.40%	100.10%
Percentage of Allowance for Credit Losses for Financing Receivables	(0.60%)	(0.40%)
Percentage Of Mortgage Loans Held For Investment Net To Mortgage Loans On Real Estate Commercial And Consumer Net	99.80%	99.70%
Percentage Of Loans And Leases Receivable Consumer Other To Mortgage Loans On Real Estate Commercial And Consumer Net	0.20%	0.20%
Percentage of total mortgage loans held-for-investments	100.00%	99.90%
Percentage of mortgage loans held-for-sale	0.00%	0.10%
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]
Mortgage Loans on Real Estate, Commercial and Consumer, Net	$ 180	$ 188
Commercial Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	$ 50,077	$ 49,624
Percentage Of Mortgage Loans, Gross	61.60%	61.60%
Residential Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	$ 14,763	$ 14,316
Percentage Of Mortgage Loans, Gross	18.20%	17.80%
Agricultural Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	$ 16,788	$ 16,695
Percentage Of Mortgage Loans, Gross	20.60%	20.70%

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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Percentage of mortgage loans held-for-sale

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Percentage of total mortgage loans held-for-investments

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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 face amount of loans that will be sold to other entities.

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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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Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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