Investments - Schedule of Residential Loans Segregated by Risk Rating Exposure and Non-accrual Loans by Amortized Cost (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Amortized Cost of Non-Accrual Loans
Amortized cost of loans on non-accrual	$ 136	$ 79
Residential Mortgages
Credit Quality Indicator Current Year
2026	1,834	1,585
2025	1,916	742
2024	617	348
2023	324	839
2022	765	756
Prior	1,081	447
Total	6,537	4,717
Credit Quality Indicator Prior Year [Abstract]
2025	1,834	1,585
2024	1,916	742
2023	617	348
2022	324	839
2021	765	756
Prior	1,081	447
Total	6,537	4,717
Amortized Cost of Non-Accrual Loans
Amortized cost of loans on non-accrual	127	67
Commercial Mortgages
Credit Quality Indicator Current Year
Total	3,829	3,260
Credit Quality Indicator Prior Year [Abstract]
Total	3,829	3,260
Amortized Cost of Non-Accrual Loans
Amortized cost of loans on non-accrual	9	12
Current (less than 30 days past due) \| Residential Mortgages
Credit Quality Indicator Current Year
2026	1,792	1,568
2025	1,885	736
2024	589	327
2023	301	798
2022	723	731
Prior	1,013	419
Total	6,303	4,579
Credit Quality Indicator Prior Year [Abstract]
2025	1,792	1,568
2024	1,885	736
2023	589	327
2022	301	798
2021	723	731
Prior	1,013	419
Total	6,303	4,579
30-89 days past due \| Residential Mortgages
Credit Quality Indicator Current Year
2026	42	15
2025	24	2
2024	7	17
2023	4	29
2022	6	4
Prior	24	3
Total	107	70
Credit Quality Indicator Prior Year [Abstract]
2025	42	15
2024	24	2
2023	7	17
2022	4	29
2021	6	4
Prior	24	3
Total	107	70
90 days or more past due \| Residential Mortgages
Credit Quality Indicator Current Year
2026	0	2
2025	7	4
2024	21	4
2023	19	12
2022	36	21
Prior	44	25
Total	127	68
Credit Quality Indicator Prior Year [Abstract]
2025	0	2
2024	7	4
2023	21	4
2022	19	12
2021	36	21
Prior	44	25
Total	$ 127	$ 68

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