Investments - Commercial Mortgage Loans Segregated by Aging of Loans and Charge Offs (Details) - Commercial Mortgages - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Credit Quality Indicator Current Year
Year one	$ 683	$ 646
Year two	591	295
Year three	274	194
Year four	195	292
Year five	292	1,252
Prior	1,794	581
Total	3,829	3,260
Credit Quality Indicator Prior Year [Abstract]
Year one	683	646
Year two	591	295
Year three	274	194
Year four	195	292
Year five	292	1,252
Prior	1,794	581
Total	3,829	3,260
Current (less than 30 days past due)
Credit Quality Indicator Current Year
Year one	683	646
Year two	591	295
Year three	274	194
Year four	195	292
Year five	292	1,252
Prior	1,785	569
Total	3,820	3,248
Credit Quality Indicator Prior Year [Abstract]
Year one	683	646
Year two	591	295
Year three	274	194
Year four	195	292
Year five	292	1,252
Prior	1,785	569
Total	3,820	3,248
30-89 days past due
Credit Quality Indicator Current Year
Year one	0	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	0
Prior	0	0
Total	0	0
Credit Quality Indicator Prior Year [Abstract]
Year one	0	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	0
Prior	0	0
Total	0	0
90 days or more past due
Credit Quality Indicator Current Year
Year one	0	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	0
Prior	9	12
Total	9	12
Credit Quality Indicator Prior Year [Abstract]
Year one	0	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	0
Prior	9	12
Total	$ 9	$ 12

Credit Quality Indicator Current Year

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Credit Quality Indicator Prior Year

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- Definition

Financing Receivable, Excluding Loans In Process, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year

+ References

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- Definition

Financing Receivable, Excluding Loans In Process, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year

+ References

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Financing Receivable, Excluding Loans In Process, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year

+ References

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- Definition

Financing Receivable, Excluding Loans In Process, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year

+ References

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- Definition

Financing Receivable, Excluding Loans In Process, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year

+ References

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Financing Receivable, Excluding Loans In Process, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477657/942-210-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478478/942-210-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(7))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

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