Investments - Amortized Cost Basis of Mortgage Loans for Each Credit Quality Indicator by Year of Origination (Details) - Commercial mortgage-backed $ in Millions	Jun. 30, 2026 USD ($)
Credit Quality Information [Abstract]
2026	$ 11
2025	226
2024	101
2023	132
2022	165
Prior	417
Total	1,052
DSCR Greater than or Equal to 1.6x, LTV Less than 55%
Credit Quality Information [Abstract]
2026
2025	38
2024
2023	33
2022	15
Prior	229
Total	315
DSCR Greater than or Equal to 1.6x, LTV 55% to 65%
Credit Quality Information [Abstract]
2026
2025	37
2024
2023	12
2022	12
Prior
Total	61
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	47
2022	4
Prior	89
Total	214
DSCR Between 1.2 to 1.6x, LTV 55% to 65%
Credit Quality Information [Abstract]
2026
2025	107
2024	33
2023	18
2022	52
Prior	19
Total	229
DSCR Between 1.2 to 1.6x, LTV Greater than 65%
Credit Quality Information [Abstract]
2026	5
2025	7
2024
2023
2022	15
Prior
Total	27
DSCR Less than or Equal to 1.2x, LTV Less than 55%
Credit Quality Information [Abstract]
2026
2025	37
2024
2023	22
2022
Prior	21
Total	80
DSCR Less than or Equal to 1.2x, LTV 55% to 65%
Credit Quality Information [Abstract]
2026
2025
2024
2023
2022	45
Prior
Total	45
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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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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-Topic 326
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