Investments - Reconciliation of Available-for-Sale Securities from Cost Basis to Fair Value (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	$ 92,842	$ 88,978
Gross Unrealized Gains	1,118	754
Gross Unrealized Losses	6,264	7,786
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	110	46	$ 19	$ 21
Fair Value	87,586	81,900
Corporate bonds
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	68,479	67,991
Gross Unrealized Gains	837	560
Gross Unrealized Losses	5,540	6,704
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	53	14	8	9
Fair Value	63,723	61,833
U.S. government bonds
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	890	427
Gross Unrealized Gains	9	3
Gross Unrealized Losses	32	40
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0	0
Fair Value	867	390
State and municipal bonds
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	2,161	2,391
Gross Unrealized Gains	35	27
Gross Unrealized Losses	231	270
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0	0
Fair Value	1,965	2,148
Foreign government bonds
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	256	277
Gross Unrealized Gains	17	12
Gross Unrealized Losses	50	56
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0	0
Fair Value	223	233
RMBS
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	2,034	1,849
Gross Unrealized Gains	45	23
Gross Unrealized Losses	108	162
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	6	7	6	7
Fair Value	1,965	1,703
CMBS
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	2,493	1,713
Gross Unrealized Gains	17	5
Gross Unrealized Losses	87	135
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0	0
Fair Value	2,423	1,583
ABS
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	16,301	14,103
Gross Unrealized Gains	137	99
Gross Unrealized Losses	210	409
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	50	24	$ 4	$ 4
Fair Value	16,178	13,769
Hybrid and redeemable preferred securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	228	227
Gross Unrealized Gains	21	25
Gross Unrealized Losses	6	10
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	1	1
Fair Value	$ 242	$ 241

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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