Investments (Credit quality indicator) (Details) - Mortgage loans $ in Millions	Sep. 30, 2024 USD ($)
Debt Securities, Available-for-sale [Line Items]
2024	$ 43
2023	126
2022	247
2021	76
2020	134
Prior	412
Total	1,038
DSCR ≥1.6x \| LTV less than 55%
Debt Securities, Available-for-sale [Line Items]
2024	0
2023	33
2022	9
2021	2
2020	97
Prior	242
Total	383
DSCR ≥1.6x \| LTV 55% to 65%
Debt Securities, Available-for-sale [Line Items]
2024	0
2023	0
2022	0
2021	5
2020	0
Prior	0
Total	5
DSCR ≥1.6x \| LTV greater than 65%
Debt Securities, Available-for-sale [Line Items]
2024	0
2023	0
2022	30
2021	12
2020	0
Prior	0
Total	42
DSCR 1.2x - 1.6x \| LTV less than 55%
Debt Securities, Available-for-sale [Line Items]
2024	0
2023	28
2022	5
2021	0
2020	13
Prior	50
Total	96
DSCR 1.2x - 1.6x \| LTV 55% to 65%
Debt Securities, Available-for-sale [Line Items]
2024	43
2023	20
2022	36
2021	36
2020	4
Prior	31
Total	170
DSCR 1.2x - 1.6x \| LTV greater than 65%
Debt Securities, Available-for-sale [Line Items]
2024	0
2023	13
2022	64
2021	0
2020	20
Prior	0
Total	97
DSCR ≤1.2 \| LTV less than 55%
Debt Securities, Available-for-sale [Line Items]
2024	0
2023	0
2022	0
2021	0
2020	0
Prior	0
Total	0
DSCR ≤1.2 \| LTV 55% to 65%
Debt Securities, Available-for-sale [Line Items]
2024	0
2023	32
2022	75
2021	0
2020	0
Prior	41
Total	148
DSCR ≤1.2 \| LTV greater than 65%
Debt Securities, Available-for-sale [Line Items]
2024	0
2023	0
2022	28
2021	21
2020	0
Prior	48
Total	$ 97

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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