Investments (Credit quality indicator) (Details) - Mortgage loans $ in Millions	Mar. 31, 2024 USD ($)
Debt Securities, Available-for-sale [Line Items]
2024	$ 12
2023	126
2022	248
2021	76
2020	134
Prior	468
Total	1,064
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	283
Total	424
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	63
Total	109
DSCR 1.2x - 1.6x \| LTV 55% to 65%
Debt Securities, Available-for-sale [Line Items]
2024	12
2023	21
2022	36
2021	36
2020	24
Prior	31
Total	160
DSCR 1.2x - 1.6x \| LTV greater than 65%
Debt Securities, Available-for-sale [Line Items]
2024	0
2023	12
2022	65
2021	0
2020	0
Prior	0
Total	77
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	43
Total	150
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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