Investments (Mortgage Loans - Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums	$ (759)	$ (946)
Financing Receivable, Purchase	1,800	3,300	$ 4,800
Mortgage Loans, Gross	$ 79,860	$ 84,344
Percentage of Mortgage Loans Classified as Performing	99.00%	99.00%
Financing Receivable, Nonaccrual	$ 822	$ 1,117
Certain Loans Acquired in Transfer Accounted for as Available-for-sale Debt Securities, Outstanding Balance			3,300
Certain Loans Acquired in Transfer Accounted for as Available-for-sale Debt Securities, Carrying Amount, Net			2,700
Certain Loans Acquired in Transfer Accounted for as Debt Securities, Accretable Yield, Accretion			178
Commercial Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	180	209
Deferred mortgage loan interest and principal payments due to COVID-19	27
Mortgage Loans, Gross	50,553	52,434
Financing Receivable, Nonaccrual	155	317	176
Financing Receivable, Nonaccrual, No Allowance	0	168
Residential Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	86	108
Deferred mortgage loan interest and principal payments due to COVID-19	18
Mortgage Loans, Gross	11,196	13,782
Financing Receivable, Nonaccrual	442	534	418
Financing Receivable, Nonaccrual, No Allowance	0	0
Agricultural Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	161	174
Deferred mortgage loan interest and principal payments due to COVID-19	4
Mortgage Loans, Gross	18,111	18,128
Financing Receivable, Nonaccrual	225	266	$ 137
Financing Receivable, Nonaccrual, No Allowance	$ 134	$ 178
Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of mortgage loans with LTV ratio in excess of 100%	1.00%
Mortgage Loans with LTV ratio in excess of 100% [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans, Gross	$ 809

Deferred commercial mortgage loan interest and principal payments due to COVID-19

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

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Percentage of commercial and agricultural mortgage loans with LTV ratio in excess of 100%

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The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and other-than-temporary impairments), for certain contractual rights to receive money on demand or on fixed or determinable dates. This relates to loans accounted for as available-for-sale debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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Current period recognition due to accretion of the excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan for loans accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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Amount of financing receivable on nonaccrual status with no allowance for credit loss.

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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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