Fair Value of Financial Instruments - Schedule of Carrying Value and Estimated Fair Value of Financial Instruments (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
ASSETS
Investments in unconsolidated affiliates	$ 256	$ 270
Total Estimated Fair Value
ASSETS
FHLB common stock	188	155
Commercial mortgage loans	3,473	3,025
Residential mortgage loans	5,919	4,424
Investments in unconsolidated affiliates	4,894	4,608
Policy loans	186	147
Company-owned life insurance	883	850
Total	15,543	13,209
Liabilities:
Investment contracts, included in Contractholder funds	53,991	51,027
Notes payable	2,131	2,289
Total	56,122	53,316
Carrying Amount
ASSETS
FHLB common stock	188	155
Commercial mortgage loans	3,799	3,242
Residential mortgage loans	6,447	4,649
Investments in unconsolidated affiliates	4,894	4,608
Policy loans	186	147
Company-owned life insurance	883	850
Total	16,397	13,651
Liabilities:
Investment contracts, included in Contractholder funds	58,613	56,184
Notes payable	2,240	2,237
Total	60,853	58,421
Level 1
ASSETS
FHLB common stock	0	0
Commercial mortgage loans	0	0
Residential mortgage loans	0	0
Investments in unconsolidated affiliates	0	0
Policy loans	0	0
Company-owned life insurance	0	0
Total	0	0
Liabilities:
Investment contracts, included in Contractholder funds	0	0
Notes payable	0	0
Total	0	0
Level 2
ASSETS
FHLB common stock	188	155
Commercial mortgage loans	0	0
Residential mortgage loans	0	0
Investments in unconsolidated affiliates	0	0
Policy loans	0	0
Company-owned life insurance	0	0
Total	188	155
Liabilities:
Investment contracts, included in Contractholder funds	0	0
Notes payable	2,131	2,289
Total	2,131	2,289
Level 3
ASSETS
FHLB common stock	0	0
Commercial mortgage loans	3,473	3,025
Residential mortgage loans	5,919	4,424
Investments in unconsolidated affiliates	0	0
Policy loans	186	147
Company-owned life insurance	883	850
Total	10,461	8,446
Liabilities:
Investment contracts, included in Contractholder funds	53,991	51,027
Notes payable	0	0
Total	53,991	51,027
NAV
ASSETS
Investments in unconsolidated affiliates	4,894	4,608
Total	$ 4,894	$ 4,608

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The carrying amount of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy.

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