Investments - Narrative (Details)	6 Months Ended
Jun. 30, 2021 USD ($) investment shares	Dec. 31, 2020 USD ($) shares
Debt Securities, Available-for-sale [Line Items]
Non-income producing investment fair value	$ 0	$ 0
Accrued interest receivable		235,000,000
FHLB collateral pledged	$ 2,256,000,000	$ 1,622,000,000
Commercial mortgage loans, percentage of investments	5.00%
DSC ratio, amortization period	25 years
Number of investments \| investment	1
Cannae Holdings Inc. \| Equity securities
Debt Securities, Available-for-sale [Line Items]
Investment owned, (in shares) \| shares	5,706,134	5,706,134
Investment owned, at fair value	$ 193,000,000	$ 253,000,000
Residential mortgage loans
Debt Securities, Available-for-sale [Line Items]
Percentage of total investments	100.00%	100.00%
% of Total	100.00%	100.00%
Limited Partnerships
Debt Securities, Available-for-sale [Line Items]
Maximum loss exposure, amount	$ 1,667,000,000
Over 90 days past due \| Residential mortgage loans
Debt Securities, Available-for-sale [Line Items]
Loans in process of foreclosure	$ 54,000,000	$ 24,400,000
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]
Loan to value, threshold (less than)	75.00%
Available-for-sale Securities
Debt Securities, Available-for-sale [Line Items]
Assets held by insurance regulators	$ 17,979,000,000	$ 16,714,000,000
Residential Mortgage
Debt Securities, Available-for-sale [Line Items]
Percentage of total investments	3.00%
% of Total	3.00%

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Highest loan to value ratio present in the loan portfolio.

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Number of investments

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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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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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The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

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