Investments (Mortgage Loans by Portfolio Segment) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	$ 84,904		$ 85,751
Allowance for Credit Loss	(1,213)	$ (981)	(1,193)	$ (800)
Total mortgage loans held-for-investment	83,691		84,558
Financing Receivable, Held-for-Sale	35	0	35
Total mortgage loans	$ 83,726		$ 84,593
Percentage Of mortgage total recorded investment To Mortgage Loans On Real Estate Commercial And Consumer Net	101.40%		101.40%
Percentage of Allowance for Credit Losses for Financing Receivables	(1.40%)		(1.40%)
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%
Other Liabilities	$ 57,989		$ 57,582
Financing Receivable, Sale	19
Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums	(759)		(789)
Financing Receivable, Purchase	1,400	912
Real Estate Acquired Through Foreclosure Of Mortgage Loans	82
Loans Originated For Third Party
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	6,100		6,500
Other Liabilities	6,100		6,500
Commercial Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	48,029		49,400
Allowance for Credit Loss	$ (885)	(697)	$ (807)	(537)
Percentage Of Mortgage Loans, Gross	57.40%		58.40%
Interest Receivable	$ 164		$ 172
Residential Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	17,520		16,800
Allowance for Credit Loss	$ (220)	(189)	$ (271)	(179)
Percentage Of Mortgage Loans, Gross	20.90%		19.90%
Interest Receivable	$ 155		$ 140
Agricultural Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	19,355		19,551
Allowance for Credit Loss	$ (108)	$ (95)	$ (115)	$ (84)
Percentage Of Mortgage Loans, Gross	23.10%		23.10%
Interest Receivable	$ 170		$ 206

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Real Estate Acquired Through Foreclosure Of Mortgage Loans

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