Investments - Amortized Cost Basis of Mortgage Loans for Each Credit Quality Indicator by Year of Origination (Details) - Commercial mortgage-backed $ in Millions	Dec. 31, 2022 USD ($)
Credit Quality Information [Abstract]
2022	$ 249
2021	94
2020	150
2019	201
2018	63
Prior	307
Total	1,064
DSCR Greater than or Equal to 1.6x, LTV Less than 55%
Credit Quality Information [Abstract]
2022	9
2021	13
2020	112
2019	41
2018	53
Prior	255
Total	483
DSCR Greater than or Equal to 1.6x, LTV 55% to 65%
Credit Quality Information [Abstract]
2022	13
2021
2020
2019
2018
Prior
Total	13
DSCR Greater than or Equal to 1.6x, LTV Greater than 65%
Credit Quality Information [Abstract]
2022	18
2021	11
2020
2019
2018
Prior
Total	29
DSCR Between 1.2 to 1.6x, LTV Less than 55%
Credit Quality Information [Abstract]
2022	5
2021	49
2020	18
2019	43
2018	10
Prior	37
Total	162
DSCR Between 1.2 to 1.6x, LTV 55% to 65%
Credit Quality Information [Abstract]
2022	86
2021
2020	20
2019
2018
Prior	8
Total	114
DSCR Between 1.2 to 1.6x, LTV Greater than 65%
Credit Quality Information [Abstract]
2022	15
2021
2020
2019
2018
Prior
Total	15
DSCR Less than or Equal to 1.2x, LTV Less than 55%
Credit Quality Information [Abstract]
2022	35
2021
2020
2019	57
2018
Prior
Total	92
DSCR Three, LTV 55 to 65%
Credit Quality Information [Abstract]
2022	41
2021	21
2020
2019	38
2018
Prior
Total	100
DSCR Less than or Equal to 1.2x, LTV Greater than 65%
Credit Quality Information [Abstract]
2022	27
2021
2020
2019	22
2018
Prior	7
Total	$ 56