Investments (Credit quality indicator) (Details) - Mortgage loans $ in Millions	Sep. 30, 2022 USD ($)
Debt Securities, Available-for-sale [Line Items]
2022	$ 129
2021	94
2020	150
2019	208
2018	64
Prior	332
Total	977
DSCR ≥1.6x | LTV less than 55%
Debt Securities, Available-for-sale [Line Items]
2022	9
2021	13
2020	112
2019	29
2018	54
Prior	275
Total	492
DSCR ≥1.6x | LTV 55% to 65%
Debt Securities, Available-for-sale [Line Items]
2022	0
2021	0
2020	0
2019	0
2018	0
Prior	0
Total	0
DSCR ≥1.6x | LTV greater than 65%
Debt Securities, Available-for-sale [Line Items]
2022	18
2021	11
2020	0
2019	0
2018	0
Prior	0
Total	29
DSCR 1.2x - 1.6x | LTV less than 55%
Debt Securities, Available-for-sale [Line Items]
2022	5
2021	49
2020	18
2019	56
2018	10
Prior	42
Total	180
DSCR 1.2x - 1.6x | LTV 55% to 65%
Debt Securities, Available-for-sale [Line Items]
2022	87
2021	0
2020	20
2019	0
2018	0
Prior	8
Total	115
DSCR 1.2x - 1.6x | LTV greater than 65%
Debt Securities, Available-for-sale [Line Items]
2022	0
2021	0
2020	0
2019	0
2018	0
Prior	0
Total	0
DSCR ≤1.2 | LTV less than 55%
Debt Securities, Available-for-sale [Line Items]
2022	0
2021	0
2020	0
2019	57
2018	0
Prior	0
Total	57
DSCR ≤1.2 | LTV 55% to 65%
Debt Securities, Available-for-sale [Line Items]
2022	0
2021	21
2020	0
2019	44
2018	0
Prior	0
Total	65
DSCR ≤1.2 | LTV greater than 65%
Debt Securities, Available-for-sale [Line Items]
2022	10
2021	0
2020	0
2019	22
2018	0
Prior	7
Total	$ 39