Investments (Credit quality indicator) (Details) - Mortgage loans $ in Millions	Mar. 31, 2025 USD ($)
Debt Securities, Available-for-sale [Line Items]
2025	$ 37
2024	101
2023	127
2022	234
2021	76
Prior	509
Total	1,084
DSCR ≥1.6x \| LTV less than 55%
Debt Securities, Available-for-sale [Line Items]
2025	0
2024	0
2023	33
2022	9
2021	0
Prior	209
Total	251
DSCR ≥1.6x \| LTV 55% to 65%
Debt Securities, Available-for-sale [Line Items]
2025	0
2024	0
2023	0
2022	15
2021	11
Prior	16
Total	42
DSCR ≥1.6x \| LTV greater than 65%
Debt Securities, Available-for-sale [Line Items]
2025	0
2024	0
2023	12
2022	31
2021	12
Prior	0
Total	55
DSCR 1.2x - 1.6x \| LTV less than 55%
Debt Securities, Available-for-sale [Line Items]
2025	0
2024	60
2023	28
2022	5
2021	2
Prior	137
Total	232
DSCR 1.2x - 1.6x \| LTV 55% to 65%
Debt Securities, Available-for-sale [Line Items]
2025	0
2024	41
2023	31
2022	20
2021	30
Prior	58
Total	180
DSCR 1.2x - 1.6x \| LTV greater than 65%
Debt Securities, Available-for-sale [Line Items]
2025	0
2024	0
2023	0
2022	46
2021	0
Prior	0
Total	46
DSCR ≤1.2 \| LTV less than 55%
Debt Securities, Available-for-sale [Line Items]
2025	0
2024	0
2023	0
2022	0
2021	0
Prior	21
Total	21
DSCR ≤1.2 \| LTV 55% to 65%
Debt Securities, Available-for-sale [Line Items]
2025	37
2024	0
2023	23
2022	73
2021	0
Prior	20
Total	153
DSCR ≤1.2 \| LTV greater than 65%
Debt Securities, Available-for-sale [Line Items]
2025	0
2024	0
2023	0
2022	35
2021	21
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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