Investments - Amortized Cost Basis of Mortgage Loans for Each Credit Quality Indicator by Year of Origination (Details) - Commercial mortgage-backed $ in Millions	Mar. 31, 2026 USD ($)
Credit Quality Information [Abstract]
2026	$ 11
2025	226
2024	101
2023	134
2022	164
Prior	434
Total	1,070
DSCR Greater than or Equal to 1.6x, LTV Less than 55%
Credit Quality Information [Abstract]
2026
2025	38
2024
2023	33
2022
Prior	219
Total	290
DSCR Greater than or Equal to 1.6x, LTV 55% to 65%
Credit Quality Information [Abstract]
2026
2025	37
2024
2023	12
2022	26
Prior	12
Total	87
DSCR Greater than or Equal to 1.6x, LTV Greater than 65%
Credit Quality Information [Abstract]
2026
2025
2024
2023
2022
Prior	13
Total	13
DSCR Between 1.2 to 1.6x, LTV Less than 55%
Credit Quality Information [Abstract]
2026	6
2025
2024	68
2023	29
2022	4
Prior	80
Total	187
DSCR Between 1.2 to 1.6x, LTV 55% to 65%
Credit Quality Information [Abstract]
2026
2025	107
2024	33
2023	38
2022	21
Prior	28
Total	227
DSCR Between 1.2 to 1.6x, LTV Greater than 65%
Credit Quality Information [Abstract]
2026	5
2025	7
2024
2023
2022	46
Prior
Total	58
DSCR Less than or Equal to 1.2x, LTV Less than 55%
Credit Quality Information [Abstract]
2026
2025
2024
2023	22
2022
Prior	21
Total	43
DSCR Less than or Equal to 1.2x, LTV 55% to 65%
Credit Quality Information [Abstract]
2026
2025	37
2024
2023
2022	45
Prior	15
Total	97
DSCR Less than or Equal to 1.2x, LTV Greater than 65%
Credit Quality Information [Abstract]
2026
2025
2024
2023
2022	22
Prior	46
Total	$ 68

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
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Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
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