Investments (Mortgage Loans - Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums	$ (828)		$ (736)
Financing Receivable, Purchase	484	$ 823
Mortgage Loans, Gross	$ 92,272		$ 93,227
Percentage of Mortgage Loans Classified as Performing	99.00%		99.00%
Commercial Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	$ 279		$ 277
Mortgage Loans, Gross	59,359		60,326
Commercial Mortgage Loans \| Extended Maturity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortized Cost of Mortgage Loans Delinquent during the period	182
Residential Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	99		95
Mortgage Loans, Gross	13,201		13,096
Agricultural Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	167		204
Mortgage Loans, Gross	$ 19,712		$ 19,805

Amortized Cost of Mortgage Loans Delinquent during the period

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The percentage of all mortgage loans that are classified as performing.

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Amount of increase in financing receivable from purchase. Excludes net investment in lease.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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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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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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