Investments (Credit quality indicator) (Details) - Mortgage loans $ in Millions	Sep. 30, 2025 USD ($)
Debt Securities, Available-for-sale [Line Items]
2025	$ 133
2024	101
2023	134
2022	230
2021	66
Prior	431
Total	1,095
DSCR ≥1.6x \| LTV less than 55%
Debt Securities, Available-for-sale [Line Items]
2025	18
2024	0
2023	33
2022	6
2021	5
Prior	210
Total	272
DSCR ≥1.6x \| LTV 55% to 65%
Debt Securities, Available-for-sale [Line Items]
2025	0
2024	0
2023	12
2022	15
2021	6
Prior	16
Total	49
DSCR ≥1.6x \| LTV greater than 65%
Debt Securities, Available-for-sale [Line Items]
2025	0
2024	0
2023	0
2022	30
2021	12
Prior	0
Total	42
DSCR 1.2x - 1.6x \| LTV less than 55%
Debt Securities, Available-for-sale [Line Items]
2025	0
2024	68
2023	28
2022	5
2021	2
Prior	93
Total	196
DSCR 1.2x - 1.6x \| LTV 55% to 65%
Debt Securities, Available-for-sale [Line Items]
2025	55
2024	33
2023	38
2022	21
2021	19
Prior	28
Total	194
DSCR 1.2x - 1.6x \| LTV greater than 65%
Debt Securities, Available-for-sale [Line Items]
2025	23
2024	0
2023	0
2022	46
2021	0
Prior	0
Total	69
DSCR ≤1.2 \| LTV less than 55%
Debt Securities, Available-for-sale [Line Items]
2025	0
2024	0
2023	6
2022	34
2021	0
Prior	21
Total	61
DSCR ≤1.2 \| LTV 55% to 65%
Debt Securities, Available-for-sale [Line Items]
2025	37
2024	0
2023	17
2022	39
2021	0
Prior	15
Total	108
DSCR ≤1.2 \| LTV greater than 65%
Debt Securities, Available-for-sale [Line Items]
2025	0
2024	0
2023	0
2022	34
2021	22
Prior	48
Total	$ 104

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

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