Investments - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Non-income producing investment fair value	$ 0	$ 0
Accrued interest receivable	253	235
FHLB collateral pledged	$ 2,469	$ 1,622
Commercial mortgage loans, percentage of investments	7.00%
DSC ratio, amortization period	25 years
Percentage of total investments		100.00%
Residential Mortgage
Debt Securities, Available-for-sale [Line Items]
Percentage of total investments	100.00%	100.00%
Residential Mortgage \| Over 90 days past due
Debt Securities, Available-for-sale [Line Items]
Mortgage loans over 90 days past due	$ 72	$ 99
Mortgage loans in process of foreclosure	$ 39	$ 24
Cannae Holdings Inc. \| Equity securities
Debt Securities, Available-for-sale [Line Items]
Investment owned, (in shares)	5,775,598	5,706,134
Investment owned, at fair value	$ 203	$ 253
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]
Loan to value, threshold (less than)	75.00%
Available-for-sale Securities
Debt Securities, Available-for-sale [Line Items]
Assets held by insurance regulators	$ 22,343	$ 16,714
Residential mortgage loans
Debt Securities, Available-for-sale [Line Items]
Percentage of total investments	4.00%

Commercial Mortgage Loans, Percentage of Investments

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Investment, Non-Income Producing, Fair Value Disclosure

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Highest loan to value ratio present in the loan portfolio.

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Residential Mortgage Loans, Location Percentage

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Percentage of the total residential loan portfolio

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

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

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Amount excluding accrued interest, before allowance for credit loss, of financing receivable.

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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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Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

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Balance held at close of period in number of shares.

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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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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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