Commercial Mortgage Loans, Percentage of Investments

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Debt Securities, Available-For-Sale, Unrealized Loss Position, Allowance For Credit Loss, Excluding Accrued Interest

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Debt Service Coverage Ratio, Amortization Period

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Financing Receivable, Allowance For Credit Loss, Probability of Loss, Default, Model, Using Reasonable And Supportable Projected Loss, Forecast Period

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Financing Receivable, Allowance For Credit Loss, Probability of Projected Loss, Default, Projection Model, Using Market Historical Loss, Period

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Investment, Non-Income Producing, Greater Than Twelve Months, Fair Value Disclosure

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Number of Loans Delinquent In Principal Or Interest Payments

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Reinsurance Agreement, Recognized Gains (Losses)

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Residential Mortgage Loans, Location Percentage

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Percentage of the total residential loan portfolio

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- Definition

Carrying amount of cash and investment securities on deposit with state regulatory authorities in connection with capital requirements.

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Amount, after allowance for credit loss, of accrued interest on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Indicates line item in statement of financial position that includes accrued interest, after allowance for credit loss, on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount excluding accrued interest, of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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- Definition

Amount, excluding accrued interest, of decrease (increase) in allowance for credit loss on financing receivable from writeoff (recovery). Excludes net investment in lease.

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- Definition

Amortized cost excluding accrued interest, of financing receivable on nonaccrual status. Excludes net investment in lease.

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- Definition

Amount, before investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Investments - Narrative (Details)	12 Months Ended
Investments - Narrative (Details)	Dec. 31, 2023 USD ($) loan	Dec. 31, 2022 USD ($) loan	Dec. 31, 2021 USD ($)
Debt Securities, Available-for-sale [Line Items]
Non-income producing investment fair value	$ 47,000,000	$ 27,000,000
Accrued interest receivable	481,000,000	365,000,000
FHLB collateral pledged	4,345,000,000	3,387,000,000
Available for sale securities, allowance for credit losses	42,000,000	39,000,000
Available-for-sale, securities in unrealized loss position, allowance for credit loss	$ 0
Commercial mortgage loans, percentage of investments	6.00%
DSC ratio, amortization period	25 years
Mortgage loans past due 90 days	$ 57,000,000	71,000,000
Gross investment income	2,864,000,000	2,088,000,000	$ 2,128,000,000
Reinsurance agreement, recognized gains (losses)	$ (123,000,000)	381,000,000	15,000,000
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Prepaid expenses and other assets
Funds Withheld for Reinsurance
Debt Securities, Available-for-sale [Line Items]
Gross investment income	$ 339,000,000	$ 109,000,000	$ 53,000,000
90 days or more past due
Debt Securities, Available-for-sale [Line Items]
Mortgage loans in process of foreclosure	$ 41,000,000
Residential Mortgage
Debt Securities, Available-for-sale [Line Items]
Percentage of total investments	7.00%	5.00%
Loan charge offs	$ 0
Mortgage loans past due 90 days	57,000,000	$ 62,000,000
Commercial Mortgage
Debt Securities, Available-for-sale [Line Items]
Mortgage loans past due 90 days	$ 0	$ 9,000,000
United States
Debt Securities, Available-for-sale [Line Items]
Residential mortgage loans, location percentage	100.00%
Commercial mortgage loans
Debt Securities, Available-for-sale [Line Items]
Number of loans delinquent in principal or interest payments \| loan	0	0
Mortgage loans \| 90 days or more past due
Debt Securities, Available-for-sale [Line Items]
Mortgage loans in process of foreclosure		$ 38,000,000
Mortgage loans \| Residential Mortgage
Debt Securities, Available-for-sale [Line Items]
Allowance for expected credit loss, probability of loss/default model, projected loss, forecast period	2 years
Allowance for credit loss, probability of loss/default, using market historical loss experience, period	3 years
Mortgage loans \| Commercial Mortgage
Debt Securities, Available-for-sale [Line Items]
Allowance for expected credit loss, probability of loss/default model, projected loss, forecast period	2 years
Allowance for credit loss, probability of loss/default, using market historical loss experience, period	3 years
Fixed maturity securities, available-for-sale
Debt Securities, Available-for-sale [Line Items]
Assets held by insurance regulators	$ 141,000,000	$ 17,870,000,000