Investments (Mortgage Loans - Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums	$ (736)	$ (744)
Financing Receivable, Purchase	1,500	3,100	$ 1,800
Mortgage Loans Contributed To Joint Ventures	15	489
Amortized Cost Of Mortgage Loans Foreclosed	37	467
Gain On Mortgage Loans Foreclosure		34
Mortgage Loans, Gross	$ 93,227	$ 84,290
Percentage of mortgage loans with LTV ratio in excess of 100%	2.00%
Percentage of Mortgage Loans Classified as Performing	99.00%	99.00%
Commercial Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	$ 277	$ 219
Mortgage Loans, Gross	60,326	52,502
Commercial Mortgage Loans \| Reinsurance Risk Transfer Transaction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Sale	254
Gain (Loss) on Sale of Financing Receivable	58
Residential Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	95	81
Mortgage Loans, Gross	13,096	12,482
Agricultural Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	204	176
Mortgage Loans, Gross	19,805	$ 19,306
Mortgage Loans with LTV ratio in excess of 100% [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	$ 1,600

Amortized Cost Of Mortgage Loans Foreclosed By Joint Venture

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Gain On Mortgage Loans Foreclosure

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Mortgage Loans Contributed To Joint Ventures

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Amount of decrease in financing receivable from sale. Excludes net investment in lease.

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