Investments - Schedule of Residential Loans Segregated by Risk Rating Exposure and Non-accrual Loans by Amortized Cost (Details) - Residential mortgage - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Credit Quality Indicator Current Year [Abstract]
2024	$ 614	$ 373
2023	376	995
2022	928	877
2021	840	208
2020	176	204
Prior	340	195
Total	3,274	2,852
Credit Quality Indicator Prior Year [Abstract]
2023	614	373
2022	376	995
2021	928	877
2020	840	208
2019	176	204
Prior	340	195
Total	3,274	2,852
Current (less than 30 days past due)
Credit Quality Indicator Current Year [Abstract]
2024	610	373
2023	368	985
2022	911	854
2021	805	192
2020	162	183
Prior	312	192
Total	3,168	2,779
Credit Quality Indicator Prior Year [Abstract]
2023	610	373
2022	368	985
2021	911	854
2020	805	192
2019	162	183
Prior	312	192
Total	3,168	2,779
30-89 days past due
Credit Quality Indicator Current Year [Abstract]
2024	1	0
2023	6	4
2022	4	7
2021	6	3
2020	1	0
Prior	3	2
Total	21	16
Credit Quality Indicator Prior Year [Abstract]
2023	1	0
2022	6	4
2021	4	7
2020	6	3
2019	1	0
Prior	3	2
Total	21	16
90 days or more past due
Credit Quality Indicator Current Year [Abstract]
2024	3	0
2023	2	6
2022	13	16
2021	29	13
2020	13	21
Prior	25	1
Total	85	57
Credit Quality Indicator Prior Year [Abstract]
2023	3	0
2022	2	6
2021	13	16
2020	29	13
2019	13	21
Prior	25	1
Total	$ 85	$ 57

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Credit Quality Indicator Prior Year

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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
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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-Section 50
-Paragraph 3B
-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Publisher FASB
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Amortized cost excluding accrued interest, of financing receivable originated more than five years prior to current fiscal year. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 79
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479294/326-20-55-79

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-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

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Amortized cost excluding accrued interest, of financing receivable originated four years prior to current fiscal year. Excludes net investment in lease.

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Amortized cost excluding accrued interest, of financing receivable originated three years prior to current fiscal year. Excludes net investment in lease.

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Amortized cost excluding accrued interest, of financing receivable originated in current fiscal year. Excludes net investment in lease.

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Amortized cost excluding accrued interest, of financing receivable originated two years prior to current fiscal year. Excludes net investment in lease.

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Amortized cost excluding accrued interest of financing receivable originated in fiscal year prior to current fiscal year. Excludes net investment in lease.

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