Investments (Mortgage Loans by Portfolio Segment) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	$ 56,176	$ 56,564
Allowance for Credit Loss	(711)	(701)	$ (629)	$ (503)
Total mortgage loans held-for-investment	55,465	55,863
Financing Receivable, Held-for-Sale	7	7	0
Total mortgage loans	$ 55,472	$ 55,870
Percentage Of mortgage total recorded investment To Mortgage Loans On Real Estate Commercial And Consumer Net	101.30%	101.30%
Percentage of Allowance for Credit Losses for Financing Receivables	(1.30%)	(1.30%)
Percentage of total mortgage loans held-for-investments	100.00%	100.00%
Percentage Of Mortgage Loans On Real Estate To Mortgage Loans On Real Estate Commercial And Consumer Net	100.00%	100.00%
Real Estate Acquired Through Foreclosure Of Mortgage Loans	$ 21
Commercial Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	28,884	$ 29,546
Allowance for Credit Loss	$ (492)	$ (436)	(425)	(312)
Percentage Of Mortgage Loans, Gross	52.10%	52.90%
Residential Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	$ 12,313	$ 11,815
Allowance for Credit Loss	$ (144)	$ (184)	(134)	(128)
Percentage Of Mortgage Loans, Gross	22.20%	21.20%
Agricultural Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	$ 14,979	$ 15,203
Allowance for Credit Loss	$ (75)	$ (81)	$ (70)	$ (63)
Percentage Of Mortgage Loans, Gross	27.00%	27.20%

Percentage Of Financing Receivable, Gross

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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 total mortgage loans held-for-investments

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Percentage Of Allowance for Credit Losses for Financing Receivables

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Real Estate Acquired Through Foreclosure Of Mortgage Loans

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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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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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