Investments - Schedule of Residential Loans Segregated by Aging of Loans (By Year of Origination) (Details) - Residential Mortgage - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Credit Quality Indicator Current Year [Abstract]
Year one	$ 195	$ 1,585
Year two	1,777	742
Year three	734	348
Year four	335	839
Year five	821	756
Prior	1,156	447
Total	5,018	4,717
Credit Quality Indicator Prior Year [Abstract]
Year one	195	1,585
Year two	1,777	742
Year three	734	348
Year four	335	839
Year five	821	756
Prior	1,156	447
Total	5,018	4,717
Current (less than 30 days past due)
Credit Quality Indicator Current Year [Abstract]
Year one	195	1,568
Year two	1,758	736
Year three	715	327
Year four	313	798
Year five	746	731
Prior	1,099	419
Total	4,826	4,579
Credit Quality Indicator Prior Year [Abstract]
Year one	195	1,568
Year two	1,758	736
Year three	715	327
Year four	313	798
Year five	746	731
Prior	1,099	419
Total	4,826	4,579
30-89 days past due
Credit Quality Indicator Current Year [Abstract]
Year one	0	15
Year two	14	2
Year three	6	17
Year four	0	29
Year five	38	4
Prior	10	3
Total	68	70
Credit Quality Indicator Prior Year [Abstract]
Year one	0	15
Year two	14	2
Year three	6	17
Year four	0	29
Year five	38	4
Prior	10	3
Total	68	70
90 days or more past due
Credit Quality Indicator Current Year [Abstract]
Year one	0	2
Year two	5	4
Year three	13	4
Year four	22	12
Year five	37	21
Prior	47	25
Total	124	68
Credit Quality Indicator Prior Year [Abstract]
Year one	0	2
Year two	5	4
Year three	13	4
Year four	22	12
Year five	37	21
Prior	47	25
Total	$ 124	$ 68

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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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-5

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- Definition

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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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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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