Investments - Principal geographic distribution of commercial real estate exceeding 5% of the mortgage loans portfolio (Details) $ in Millions	Dec. 31, 2021 USD ($) loan	Dec. 31, 2020 USD ($)
Schedule of Available for Sale Securities
Number of loans | loan	53
Mortgage loans, net | $	$ 821	$ 746
Mortgage loans on real estate, carrying value (percentage)	100.00%	100.00%
2022 | Mortgage loans
Schedule of Available for Sale Securities
Number of loans | loan	5
Mortgage loans, net | $	$ 98
Mortgage loans on real estate, carrying value (percentage)	11.90%
2023 | Mortgage loans
Schedule of Available for Sale Securities
Number of loans | loan	6
Mortgage loans, net | $	$ 44
Mortgage loans on real estate, carrying value (percentage)	5.40%
2024 | Mortgage loans
Schedule of Available for Sale Securities
Number of loans | loan	5
Mortgage loans, net | $	$ 89
Mortgage loans on real estate, carrying value (percentage)	10.80%
2025 | Mortgage loans
Schedule of Available for Sale Securities
Number of loans | loan	7
Mortgage loans, net | $	$ 115
Mortgage loans on real estate, carrying value (percentage)	14.00%
Thereafter | Mortgage loans
Schedule of Available for Sale Securities
Number of loans | loan	30
Mortgage loans, net | $	$ 475
Mortgage loans on real estate, carrying value (percentage)	57.90%
Apartment complex
Schedule of Available for Sale Securities
Mortgage loans on real estate, carrying value (percentage)	35.30%	53.20%
Retail
Schedule of Available for Sale Securities
Mortgage loans on real estate, carrying value (percentage)	23.80%	7.90%
Office
Schedule of Available for Sale Securities
Mortgage loans on real estate, carrying value (percentage)	18.50%	21.80%
Warehouse
Schedule of Available for Sale Securities
Mortgage loans on real estate, carrying value (percentage)	11.00%	14.20%
Other
Schedule of Available for Sale Securities
Mortgage loans on real estate, carrying value (percentage)	11.40%	2.90%
Texas
Schedule of Available for Sale Securities
Mortgage loans on real estate, carrying value (percentage)	20.40%	22.00%
California
Schedule of Available for Sale Securities
Mortgage loans on real estate, carrying value (percentage)	19.60%	15.60%
Illinois
Schedule of Available for Sale Securities
Mortgage loans on real estate, carrying value (percentage)	6.70%	2.40%
Florida
Schedule of Available for Sale Securities
Mortgage loans on real estate, carrying value (percentage)	6.00%	8.60%
Massachusetts
Schedule of Available for Sale Securities
Mortgage loans on real estate, carrying value (percentage)	5.70%	3.60%
Tennessee
Schedule of Available for Sale Securities
Mortgage loans on real estate, carrying value (percentage)	5.70%	4.70%
Ohio
Schedule of Available for Sale Securities
Mortgage loans on real estate, carrying value (percentage)	5.30%	7.20%
Missouri
Schedule of Available for Sale Securities
Mortgage loans on real estate, carrying value (percentage)	4.40%	5.70%