Investments - Narrative (Details) $ in Millions	3 Months Ended
Mar. 31, 2022 USD ($) swap security	Dec. 31, 2021 USD ($)
Schedule of Investments [Line Items]
Unfunded commitments to limited partnerships	$ 354	$ 366
Percentage (based on amount of unrealized loss) of available for sale fixed maturities that are in an unrealized loss position and rated investment grade	94.00%
Percentage (based on fair value) of available for sale fixed maturities that are in an unrealized loss position and rated investment grade	95.00%
Interest rate swaps \| Cash flow hedging \| Designated as hedging instrument
Schedule of Investments [Line Items]
Number of interest rate swaps designated and qualifying as a cash flow hedges \| swap	5
Derivative, notional amount	$ 408
Derivative fair value	(5)
Gain (loss) reclassified from AOCI into net investment income	1
Receivable for collateral posted related to swaps	$ 15
Multifamily
Schedule of Investments [Line Items]
Percent of real-estate related investments by property type	88.00%	88.00%
Single Family
Schedule of Investments [Line Items]
Percent of real-estate related investments by property type	1.00%	1.00%
Other Property
Schedule of Investments [Line Items]
Percent of real-estate related investments by property type	11.00%	11.00%
Fixed maturities
Schedule of Investments [Line Items]
Gross unrealized losses on fixed maturities	$ 220	$ 28
Number of available for sale securities in an unrealized loss position \| security	1,128,000,000

Number of available-for-sale securities in an unrealized loss position.

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Receivable for collateral posted related to swaps

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

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