Investments - Schedule of Information About Credit Quality and Vintage Year of Commercial Mortgage Loans (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	$ 2,626	$ 1,833
Year two	1,726	866
Year three	793	641
Year four	547	826
Year five	667	796
Prior	4,909	5,249
Revolving Loans	0	0
Total with ACL	$ 11,268	$ 10,211
% of Total	100.00%	100.00%
Commercial mortgage loans
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	$ 1,767	$ 1,346
Year two	1,325	639
Year three	633	608
Year four	537	789
Year five	652	722
Prior	4,499	4,853
Revolving Loans	0	0
Total with ACL	$ 9,413	$ 8,957
% of Total	100.00%	100.00%
Commercial mortgage loans \| Non-income producing properties
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	$ 0
Year two	44
Year three	0
Year four	0
Year five	0
Prior	26
Revolving Loans	0
Total with ACL	$ 70
% of Total	1.00%
Residential mortgage loans
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	$ 859	$ 487
Year two	401	227
Year three	160	33
Year four	10	37
Year five	15	74
Prior	410	396
Revolving Loans	0	0
Total with ACL	$ 1,855	$ 1,254
% of Total	100.00%	100.00%
Residential mortgage loans \| Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	$ 857	$ 487
Year two	396	223
Year three	157	17
Year four	4	17
Year five	10	71
Prior	386	375
Revolving Loans	0	0
Total with ACL	$ 1,810	$ 1,190
% of Total	98.00%	95.00%
Residential mortgage loans \| Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	$ 2	$ 0
Year two	5	4
Year three	3	16
Year four	6	20
Year five	5	3
Prior	24	21
Revolving Loans	0	0
Total with ACL	$ 45	$ 64
% of Total	2.00%	5.00%
Greater than 1.20x \| Commercial mortgage loans
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	$ 1,404	$ 1,313
Year two	1,246	615
Year three	633	538
Year four	431	594
Year five	519	434
Prior	3,942	4,591
Revolving Loans	0	0
Total with ACL	$ 8,175	$ 8,085
% of Total	87.00%	90.00%
1.00x - 1.20x \| Commercial mortgage loans
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	$ 236	$ 33
Year two	35	24
Year three	0	70
Year four	90	145
Year five	44	174
Prior	366	231
Revolving Loans	0	0
Total with ACL	$ 771	$ 677
% of Total	8.00%	8.00%
Less than 1.00x \| Commercial mortgage loans
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	$ 127	$ 0
Year two	0	0
Year three	0	0
Year four	16	50
Year five	89	114
Prior	165	31
Revolving Loans	0	0
Total with ACL	$ 397	$ 195
% of Total	4.00%	2.00%
Less than 70% \| Commercial mortgage loans
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	$ 1,737	$ 1,140
Year two	1,322	508
Year three	633	521
Year four	523	466
Year five	441	345
Prior	3,937	4,296
Revolving Loans	0	0
Total with ACL	$ 8,593	$ 7,276
% of Total	91.00%	81.00%
70% - 80% \| Commercial mortgage loans
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	$ 30	$ 206
Year two	0	129
Year three	0	62
Year four	14	221
Year five	132	353
Prior	397	316
Revolving Loans	0	0
Total with ACL	$ 573	$ 1,287
% of Total	6.00%	14.00%
80% - 100% \| Commercial mortgage loans
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	$ 0	$ 0
Year two	0	0
Year three	0	25
Year four	0	46
Year five	34	24
Prior	91	151
Revolving Loans	0	0
Total with ACL	$ 125	$ 246
% of Total	2.00%	3.00%
Greater than 100% \| Commercial mortgage loans
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	$ 0	$ 0
Year two	3	2
Year three	0	0
Year four	0	56
Year five	45	0
Prior	74	90
Revolving Loans	0	0
Total with ACL	$ 122	$ 148
% of Total	1.00%	2.00%

Percentage, before allowance for credit loss, of financing receivable to total financing receivable.

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