Investments (Credit quality indicator) (Details) - Mortgage loans $ in Millions	Mar. 31, 2026 USD ($)
Debt Securities, Available-for-sale [Line Items]
2026	$ 11
2025	226
2024	101
2023	134
2022	164
Prior	434
Total	1,070
DSCR ≥1.6x \| LTV less than 55%
Debt Securities, Available-for-sale [Line Items]
2026	0
2025	38
2024	0
2023	33
2022	0
Prior	219
Total	290
DSCR ≥1.6x \| LTV 55% to 65%
Debt Securities, Available-for-sale [Line Items]
2026	0
2025	37
2024	0
2023	12
2022	26
Prior	12
Total	87
DSCR ≥1.6x \| LTV greater than 65%
Debt Securities, Available-for-sale [Line Items]
2026	0
2025	0
2024	0
2023	0
2022	0
Prior	13
Total	13
DSCR 1.2x - 1.6x \| LTV less than 55%
Debt Securities, Available-for-sale [Line Items]
2026	6
2025	0
2024	68
2023	29
2022	4
Prior	80
Total	187
DSCR 1.2x - 1.6x \| LTV 55% to 65%
Debt Securities, Available-for-sale [Line Items]
2026	0
2025	107
2024	33
2023	38
2022	21
Prior	28
Total	227
DSCR 1.2x - 1.6x \| LTV greater than 65%
Debt Securities, Available-for-sale [Line Items]
2026	5
2025	7
2024	0
2023	0
2022	46
Prior	0
Total	58
DSCR ≤1.2 \| LTV less than 55%
Debt Securities, Available-for-sale [Line Items]
2026	0
2025	0
2024	0
2023	22
2022	0
Prior	21
Total	43
DSCR ≤1.2 \| LTV 55% to 65%
Debt Securities, Available-for-sale [Line Items]
2026	0
2025	37
2024	0
2023	0
2022	45
Prior	15
Total	97
DSCR ≤1.2 \| LTV greater than 65%
Debt Securities, Available-for-sale [Line Items]
2026	0
2025	0
2024	0
2023	0
2022	22
Prior	46
Total	$ 68

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

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