Investments - Amortized Cost Basis of Mortgage Loans for Each Credit Quality Indicator by Year of Origination (Details) - Commercial mortgage-backed $ in Millions	Dec. 31, 2024 USD ($)
Credit Quality Information [Abstract]
2024	$ 102
2023	127
2022	236
2021	76
2020	133
Prior	380
Total	1,054
DSCR Greater than or Equal to 1.6x, LTV Less than 55%
Credit Quality Information [Abstract]
2024
2023	34
2022	9
2021
2020	60
Prior	169
Total	272
DSCR Greater than or Equal to 1.6x, LTV 55% to 65%
Credit Quality Information [Abstract]
2024
2023
2022	15
2021	11
2020	4
Prior	12
Total	42
DSCR Greater than or Equal to 1.6x, LTV Greater than 65%
Credit Quality Information [Abstract]
2024
2023	13
2022	30
2021	12
2020
Prior
Total	55
DSCR Between 1.2 to 1.6x, LTV Less than 55%
Credit Quality Information [Abstract]
2024	49
2023	28
2022	5
2021	2
2020	49
Prior	71
Total	204
DSCR Between 1.2 to 1.6x, LTV 55% to 65%
Credit Quality Information [Abstract]
2024	53
2023	30
2022	21
2021	30
2020	20
Prior	39
Total	193
DSCR Between 1.2 to 1.6x, LTV Greater than 65%
Credit Quality Information [Abstract]
2024
2023
2022	46
2021
2020
Prior
Total	46
DSCR Less than or Equal to 1.2x, LTV Less than 55%
Credit Quality Information [Abstract]
2024
2023
2022
2021
2020
Prior	21
Total	21
DSCR Three, LTV 55 to 65%
Credit Quality Information [Abstract]
2024
2023	22
2022	75
2021
2020
Prior	20
Total	117
DSCR Less than or Equal to 1.2x, LTV Greater than 65%
Credit Quality Information [Abstract]
2024
2023
2022	35
2021	21
2020
Prior	48
Total	$ 104

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- Definition

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

+ References

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-Topic 326
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Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
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