Claim and Claim Adjustment Expense Reserves (International - Net Incurred Claims and Allocated Claim Adjustment Expenses) (Details) - International $ in Millions	Dec. 31, 2025 USD ($) claim	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items]
Incurred claims and allocated claim adjustment expense, net	$ 6,426
IBNR	1,914
2016
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items]
Incurred claims and allocated claim adjustment expense, net	550	$ 540	$ 543	$ 520	$ 518	$ 508	$ 516	$ 530	$ 556	$ 519
IBNR	$ 41
Cumulative Number of Claims | claim	26,135
2017
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items]
Incurred claims and allocated claim adjustment expense, net	$ 668	665	644	620	632	630	636	626	$ 551
IBNR	$ 29
Cumulative Number of Claims | claim	27,478
2018
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items]
Incurred claims and allocated claim adjustment expense, net	$ 745	746	747	719	706	701	693	$ 646
IBNR	$ 34
Cumulative Number of Claims | claim	34,444
2019
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items]
Incurred claims and allocated claim adjustment expense, net	$ 605	600	594	595	580	588	$ 572
IBNR	$ 59
Cumulative Number of Claims | claim	31,242
2020
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items]
Incurred claims and allocated claim adjustment expense, net	$ 537	549	552	570	584	$ 602
IBNR	$ 103
Cumulative Number of Claims | claim	23,395
2021
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items]
Incurred claims and allocated claim adjustment expense, net	$ 516	520	538	574	$ 595
IBNR	$ 139
Cumulative Number of Claims | claim	20,159
2022
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items]
Incurred claims and allocated claim adjustment expense, net	$ 608	633	635	$ 628
IBNR	$ 211
Cumulative Number of Claims | claim	16,985
2023
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items]
Incurred claims and allocated claim adjustment expense, net	$ 658	679	$ 691
IBNR	$ 318
Cumulative Number of Claims | claim	15,977
2024
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items]
Incurred claims and allocated claim adjustment expense, net	$ 780	$ 743
IBNR	$ 436
Cumulative Number of Claims | claim	14,380
2025
Short-duration Insurance Contracts, Net Incurred Claim and Claim Adjustment Expenses [Line Items]
Incurred claims and allocated claim adjustment expense, net	$ 759
IBNR	$ 544
Cumulative Number of Claims | claim	9,708