Investments - Narrative (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022 USD ($)	Sep. 30, 2022 USD ($) security	Dec. 31, 2021 USD ($)
Schedule of Investments [Line Items]
Unfunded commitments to limited partnerships	$ 389	$ 389	$ 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		94.00%
Interest rate swaps \| Cash flow hedging \| Designated as hedging instrument
Schedule of Investments [Line Items]
Derivative, notional amount	1,220	$ 1,220
Derivative liability	37	37
Gain (loss) reclassified from AOCI into net investment income	1	3
Receivable for collateral posted related to swaps	63	63
Interest rate swaps \| Cash flow hedging \| Designated as hedging instrument \| Maximum
Schedule of Investments [Line Items]
Derivative asset	$ 1	$ 1
Multifamily
Schedule of Investments [Line Items]
Percent of real-estate related investments by property type	92.00%	92.00%	88.00%
Single Family
Schedule of Investments [Line Items]
Percent of real-estate related investments by property type	1.00%	1.00%	1.00%
Other Property
Schedule of Investments [Line Items]
Percent of real-estate related investments by property type	7.00%	7.00%	11.00%
Fixed maturities
Schedule of Investments [Line Items]
Gross unrealized losses on fixed maturities	$ 728	$ 728	$ 28
Number of available for sale securities in an unrealized loss position \| security		1,900,000,000

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