Investments - Narrative (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022 USD ($) swap	Jun. 30, 2022 USD ($) security swap	Dec. 31, 2021 USD ($)
Schedule of Investments [Line Items]
Unfunded commitments to limited partnerships	$ 369	$ 369	$ 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		93.00%
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]
Number of interest rate swaps designated and qualifying as a cash flow hedges \| swap	11	11
Derivative, notional amount	$ 658	$ 658
Derivative asset	1	1
Derivative liability	11	11
Gain (loss) reclassified from AOCI into net investment income	1	2
Receivable for collateral posted related to swaps	$ 30	$ 30
Multifamily
Schedule of Investments [Line Items]
Percent of real-estate related investments by property type	91.00%	91.00%	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	8.00%	8.00%	11.00%
Fixed maturities
Schedule of Investments [Line Items]
Gross unrealized losses on fixed maturities	$ 454	$ 454	$ 28
Number of available for sale securities in an unrealized loss position \| security		1,600,000,000

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