Insurance Liabilities - Undiscounted, Incurred and Paid Losses and Allocated Loss Adjustment Expenses (Details) $ 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 ($)	Dec. 31, 2016 USD ($)
U.S. Workers' Compensation (before discount)
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	$ 6,075
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 3,004
Year 1 (as a percent)	11.00%
Year 2 (as a percent)	17.00%
Year 3 (as a percent)	10.50%
Year 4 (as a percent)	7.70%
Year 5 (as a percent)	4.80%
Year 6 (as a percent)	3.60%
Year 7 (as a percent)	2.60%
Year 8 (as a percent)	1.10%
Year 9 (as a percent)	1.10%
Year 10 (as a percent)	0.80%
U.S. Workers' Compensation (before discount) | 2016
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	$ 957	$ 986	$ 1,025	$ 1,036	$ 1,075	$ 1,090	$ 1,140	$ 1,318	$ 1,346	$ 1,299
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 137
Cumulative Number of Reported Claims | claim	32,431
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 715	708	694	686	662	630	584	521	378	147
U.S. Workers' Compensation (before discount) | 2017
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	664	673	705	712	731	763	776	850	789
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 158
Cumulative Number of Reported Claims | claim	28,371
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 407	402	395	389	367	333	294	224	93
U.S. Workers' Compensation (before discount) | 2018
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	769	786	875	896	911	961	1,021	998
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 167
Cumulative Number of Reported Claims | claim	22,736
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 459	448	409	388	359	296	215	85
U.S. Workers' Compensation (before discount) | 2019
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	684	730	788	801	812	873	887
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 141
Cumulative Number of Reported Claims | claim	17,596
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 431	417	389	347	301	219	93
U.S. Workers' Compensation (before discount) | 2020
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	421	434	477	521	573	597
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 86
Cumulative Number of Reported Claims | claim	14,305
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 279	259	245	205	159	64
U.S. Workers' Compensation (before discount) | 2021
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	533	514	545	570	597
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 197
Cumulative Number of Reported Claims | claim	11,490
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 241	211	171	128	60
U.S. Workers' Compensation (before discount) | 2022
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	496	464	493	523
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 202
Cumulative Number of Reported Claims | claim	10,079
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 189	143	102	45
U.S. Workers' Compensation (before discount) | 2023
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	476	465	500
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 222
Cumulative Number of Reported Claims | claim	9,332
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 144	103	38
U.S. Workers' Compensation (before discount) | 2024
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	540	567
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 280
Cumulative Number of Reported Claims | claim	7,683
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 104	35
U.S. Workers' Compensation (before discount) | 2025
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	535
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 484
Cumulative Number of Reported Claims | claim	5,476
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 35
U.S. Workers' Compensation (before discount) | Accident Years prior to 2016
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	374
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	10
U.S. Workers' Compensation (before discount) | Short Duration Insurance Contracts Last Ten Accident Years
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	3,071
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	(79)
U.S. Workers' Compensation (before discount) | All Accident Years
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	3,445
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	(69)
Prior Year Development for Unallocated Loss Adjustment Expense, Undiscounted and Net of Reinsurance including ADC, All Accident Years	(44)
Prior Year Development for Loss and Loss Adjustment Expense, Undiscounted and Net of Reinsurance including ADC, All Accident Years	(113)
U.S. Excess Casualty
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	6,215
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 3,517
Year 1 (as a percent)	1.10%
Year 2 (as a percent)	10.60%
Year 3 (as a percent)	8.30%
Year 4 (as a percent)	19.70%
Year 5 (as a percent)	10.90%
Year 6 (as a percent)	6.90%
Year 7 (as a percent)	6.40%
Year 8 (as a percent)	7.60%
Year 9 (as a percent)	3.50%
Year 10 (as a percent)	10.40%
U.S. Excess Casualty | 2016
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	$ 1,305	1,317	1,276	1,263	1,250	1,274	1,171	1,162	1,146	898
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 226
Cumulative Number of Reported Claims | claim	3,064
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 986	851	798	670	566	502	388	204	80	28
U.S. Excess Casualty | 2017
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,270	1,228	1,182	1,200	1,157	1,153	1,097	1,002	856
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 257
Cumulative Number of Reported Claims | claim	2,358
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 898	860	781	676	585	505	156	45	1
U.S. Excess Casualty | 2018
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	762	779	779	769	769	721	646	648
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 110
Cumulative Number of Reported Claims | claim	1,764
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 579	527	494	414	315	227	125	1
U.S. Excess Casualty | 2019
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	584	604	600	612	597	583	577
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 225
Cumulative Number of Reported Claims | claim	1,588
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 282	253	216	157	79	43	7
U.S. Excess Casualty | 2020
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	395	404	420	410	413	406
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 166
Cumulative Number of Reported Claims | claim	1,570
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 209	188	128	33	15	4
U.S. Excess Casualty | 2021
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	383	358	274	277	278
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 113
Cumulative Number of Reported Claims | claim	1,196
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 207	161	62	43	4
U.S. Excess Casualty | 2022
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	369	333	305	305
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 104
Cumulative Number of Reported Claims | claim	824
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 177	96	51	14
U.S. Excess Casualty | 2023
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	373	348	345
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 179
Cumulative Number of Reported Claims | claim	740
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 115	89	1
U.S. Excess Casualty | 2024
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	315	315
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 214
Cumulative Number of Reported Claims | claim	446
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 59	0
U.S. Excess Casualty | 2025
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	459
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 451
Cumulative Number of Reported Claims | claim	185
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 5
U.S. Excess Casualty | Accident Years prior to 2016
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	455
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	(2)
U.S. Excess Casualty | Short Duration Insurance Contracts Last Ten Accident Years
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	2,698
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	70
U.S. Excess Casualty | All Accident Years
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	3,153
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	68
Prior Year Development for Unallocated Loss Adjustment Expense, Undiscounted and Net of Reinsurance including ADC, All Accident Years	14
Prior Year Development for Loss and Loss Adjustment Expense, Undiscounted and Net of Reinsurance including ADC, All Accident Years	82
U.S. Other Casualty
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	8,691
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 4,329
Year 1 (as a percent)	5.30%
Year 2 (as a percent)	9.60%
Year 3 (as a percent)	11.90%
Year 4 (as a percent)	13.20%
Year 5 (as a percent)	12.60%
Year 6 (as a percent)	9.20%
Year 7 (as a percent)	7.10%
Year 8 (as a percent)	4.50%
Year 9 (as a percent)	2.90%
Year 10 (as a percent)	2.30%
U.S. Other Casualty | 2016
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	$ 1,241	1,264	1,297	1,293	1,323	1,340	1,391	1,321	1,343	1,339
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 35
Cumulative Number of Reported Claims | claim	29,467
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,173	1,144	1,074	1,018	938	846	703	489	298	77
U.S. Other Casualty | 2017
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	654	662	654	643	668	674	738	629	602
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 21
Cumulative Number of Reported Claims | claim	21,436
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 615	613	592	527	455	314	216	111	51
U.S. Other Casualty | 2018
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	852	841	810	824	870	837	845	802
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 115
Cumulative Number of Reported Claims | claim	17,192
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 685	636	565	470	360	227	122	43
U.S. Other Casualty | 2019
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,009	1,024	1,039	1,062	1,053	1,058	1,059
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 432
Cumulative Number of Reported Claims | claim	21,479
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 510	474	410	321	226	138	53
U.S. Other Casualty | 2020
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	499	519	540	538	576	524
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 166
Cumulative Number of Reported Claims | claim	11,792
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 301	252	198	139	73	26
U.S. Other Casualty | 2021
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	845	818	790	793	795
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 461
Cumulative Number of Reported Claims | claim	11,552
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 351	265	169	87	32
U.S. Other Casualty | 2022
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	861	827	819	793
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 495
Cumulative Number of Reported Claims | claim	14,193
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 299	195	112	38
U.S. Other Casualty | 2023
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	983	955	933
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 698
Cumulative Number of Reported Claims | claim	14,983
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 205	102	36
U.S. Other Casualty | 2024
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	871	840
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 709
Cumulative Number of Reported Claims | claim	11,999
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 128	37
U.S. Other Casualty | 2025
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	876
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 734
Cumulative Number of Reported Claims | claim	7,487
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 62
U.S. Other Casualty | Accident Years prior to 2016
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	289
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	(62)
U.S. Other Casualty | Short Duration Insurance Contracts Last Ten Accident Years
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	4,362
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	65
U.S. Other Casualty | All Accident Years
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	4,651
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	3
Prior Year Development for Unallocated Loss Adjustment Expense, Undiscounted and Net of Reinsurance including ADC, All Accident Years	19
Prior Year Development for Loss and Loss Adjustment Expense, Undiscounted and Net of Reinsurance including ADC, All Accident Years	22
U.S. Financial Lines
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	15,342
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 10,100
Year 1 (as a percent)	4.00%
Year 2 (as a percent)	14.30%
Year 3 (as a percent)	15.70%
Year 4 (as a percent)	14.80%
Year 5 (as a percent)	12.50%
Year 6 (as a percent)	8.00%
Year 7 (as a percent)	6.50%
Year 8 (as a percent)	5.50%
Year 9 (as a percent)	2.30%
Year 10 (as a percent)	2.30%
U.S. Financial Lines | 2016
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	$ 2,345	2,322	2,308	2,325	2,281	2,139	2,064	1,993	1,855	1,605
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 95
Cumulative Number of Reported Claims | claim	16,143
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 2,169	2,115	2,039	1,903	1,826	1,659	1,358	1,002	499	73
U.S. Financial Lines | 2017
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,966	1,969	1,957	1,987	1,898	1,846	1,756	1,675	1,564
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 108
Cumulative Number of Reported Claims | claim	15,293
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,805	1,777	1,653	1,515	1,396	1,118	761	391	64
U.S. Financial Lines | 2018
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	2,260	2,282	2,322	2,225	2,063	1,882	1,766	1,640
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 291
Cumulative Number of Reported Claims | claim	14,867
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,879	1,776	1,601	1,415	1,126	835	486	86
U.S. Financial Lines | 2019
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,961	1,945	1,912	1,926	1,627	1,536	1,503
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 266
Cumulative Number of Reported Claims | claim	13,406
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,575	1,423	1,204	953	642	367	94
U.S. Financial Lines | 2020
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,480	1,470	1,457	1,408	1,252	1,213
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 162
Cumulative Number of Reported Claims | claim	10,495
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,171	1,063	915	648	356	84
U.S. Financial Lines | 2021
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,244	1,316	1,388	1,408	1,430
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 514
Cumulative Number of Reported Claims | claim	7,280
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 628	468	315	151	43
U.S. Financial Lines | 2022
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,057	1,105	1,108	1,130
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 695
Cumulative Number of Reported Claims | claim	5,985
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 293	177	109	30
U.S. Financial Lines | 2023
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,075	1,041	1,043
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 574
Cumulative Number of Reported Claims | claim	7,100
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 324	150	46
U.S. Financial Lines | 2024
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	955	942
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 636
Cumulative Number of Reported Claims | claim	7,791
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 216	44
U.S. Financial Lines | 2025
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	999
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 927
Cumulative Number of Reported Claims | claim	8,079
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 40
U.S. Financial Lines | Accident Years prior to 2016
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	28
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	20
U.S. Financial Lines | Short Duration Insurance Contracts Last Ten Accident Years
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	5,242
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	(49)
U.S. Financial Lines | All Accident Years
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	5,270
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	(29)
Prior Year Development for Unallocated Loss Adjustment Expense, Undiscounted and Net of Reinsurance including ADC, All Accident Years	(16)
Prior Year Development for Loss and Loss Adjustment Expense, Undiscounted and Net of Reinsurance including ADC, All Accident Years	(45)
U.S. Property and Special Risks
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	27,208
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 23,320
Year 1 (as a percent)	36.40%
Year 2 (as a percent)	30.10%
Year 3 (as a percent)	10.40%
Year 4 (as a percent)	7.10%
Year 5 (as a percent)	4.70%
Year 6 (as a percent)	3.70%
Year 7 (as a percent)	2.40%
Year 8 (as a percent)	1.50%
Year 9 (as a percent)	0.90%
Year 10 (as a percent)	0.30%
U.S. Property and Special Risks | 2016
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	$ 2,731	2,727	2,713	2,700	2,694	2,707	2,697	2,690	2,748	2,674
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 6
Cumulative Number of Reported Claims | claim	54,963
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 2,688	2,679	2,647	2,616	2,539	2,464	2,296	2,076	1,747	821
U.S. Property and Special Risks | 2017
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	4,178	4,187	4,175	4,212	4,173	4,153	4,127	4,239	4,569
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 6
Cumulative Number of Reported Claims | claim	79,982
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 4,151	4,129	4,055	3,999	3,897	3,638	3,281	2,625	1,137
U.S. Property and Special Risks | 2018
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	3,203	3,204	3,210	3,201	3,229	2,992	2,993	2,978
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 10
Cumulative Number of Reported Claims | claim	70,274
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 3,144	3,094	2,994	2,863	2,715	2,509	2,162	977
U.S. Property and Special Risks | 2019
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	2,215	2,198	2,177	2,222	2,211	2,146	2,177
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 24
Cumulative Number of Reported Claims | claim	79,150
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 2,176	2,124	2,083	2,037	1,906	1,673	1,039
U.S. Property and Special Risks | 2020
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	3,289	3,269	3,238	3,280	3,320	3,391
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 464
Cumulative Number of Reported Claims | claim	69,329
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 2,657	2,414	2,190	1,874	1,613	844
U.S. Property and Special Risks | 2021
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	2,180	2,190	2,160	2,213	2,339
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 92
Cumulative Number of Reported Claims | claim	82,535
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 2,061	2,004	1,983	1,743	878
U.S. Property and Special Risks | 2022
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	3,234	3,240	3,281	3,171
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 249
Cumulative Number of Reported Claims | claim	87,066
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 2,769	2,437	2,207	1,208
U.S. Property and Special Risks | 2023
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	2,367	2,440	2,528
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 326
Cumulative Number of Reported Claims | claim	100,257
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,878	1,692	1,173
U.S. Property and Special Risks | 2024
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,714	1,844
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 426
Cumulative Number of Reported Claims | claim	31,463
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,012	667
U.S. Property and Special Risks | 2025
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	2,097
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 739
Cumulative Number of Reported Claims | claim	22,479
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 784
U.S. Property and Special Risks | Accident Years prior to 2016
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	254
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	34
U.S. Property and Special Risks | Short Duration Insurance Contracts Last Ten Accident Years
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	3,888
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	(188)
U.S. Property and Special Risks | All Accident Years
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	4,142
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	(154)
Prior Year Development for Unallocated Loss Adjustment Expense, Undiscounted and Net of Reinsurance including ADC, All Accident Years	4
Prior Year Development for Loss and Loss Adjustment Expense, Undiscounted and Net of Reinsurance including ADC, All Accident Years	(150)
U.S. Personal Insurance
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	10,796
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 10,050
Year 1 (as a percent)	57.40%
Year 2 (as a percent)	24.50%
Year 3 (as a percent)	4.90%
Year 4 (as a percent)	1.80%
Year 5 (as a percent)	2.60%
Year 6 (as a percent)	1.00%
Year 7 (as a percent)	0.70%
Year 8 (as a percent)	0.70%
Year 9 (as a percent)	0.20%
Year 10 (as a percent)	0.10%
U.S. Personal Insurance | 2016
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	$ 1,540	1,541	1,541	1,544	1,544	1,542	1,540	1,533	1,533	1,536
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 16
Cumulative Number of Reported Claims | claim	247,862
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,522	1,521	1,521	1,518	1,512	1,501	1,460	1,422	1,344	857
U.S. Personal Insurance | 2017
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,898	1,899	1,896	1,916	1,924	2,057	2,011	2,137	1,878
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 12
Cumulative Number of Reported Claims | claim	220,439
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,884	1,878	1,861	1,852	1,826	1,789	1,896	1,672	941
U.S. Personal Insurance | 2018
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,924	1,927	1,920	1,936	1,937	2,154	2,193	2,188
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 24
Cumulative Number of Reported Claims | claim	102,585
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,900	1,881	1,849	1,832	1,789	1,973	1,939	1,227
U.S. Personal Insurance | 2019
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,565	1,569	1,578	1,596	1,646	1,664	1,593
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 45
Cumulative Number of Reported Claims | claim	94,184
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,517	1,516	1,491	1,416	1,379	1,295	884
U.S. Personal Insurance | 2020
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	888	890	894	913	906	954
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 37
Cumulative Number of Reported Claims | claim	56,199
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 850	846	824	725	679	667
U.S. Personal Insurance | 2021
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	747	752	762	765	748
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 53
Cumulative Number of Reported Claims | claim	57,895
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 676	662	658	650	488
U.S. Personal Insurance | 2022
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	523	525	529	517
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 51
Cumulative Number of Reported Claims | claim	56,476
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 464	406	401	372
U.S. Personal Insurance | 2023
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	688	668	677
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 53
Cumulative Number of Reported Claims | claim	50,195
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 579	522	400
U.S. Personal Insurance | 2024
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	594	604
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 67
Cumulative Number of Reported Claims | claim	41,541
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 516	273
U.S. Personal Insurance | 2025
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	429
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 216
Cumulative Number of Reported Claims | claim	23,548
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 142
U.S. Personal Insurance | Accident Years prior to 2016
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	(41)
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	(1)
U.S. Personal Insurance | Short Duration Insurance Contracts Last Ten Accident Years
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	746
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	(8)
U.S. Personal Insurance | All Accident Years
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	705
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	(9)
Prior Year Development for Unallocated Loss Adjustment Expense, Undiscounted and Net of Reinsurance including ADC, All Accident Years	(2)
Prior Year Development for Loss and Loss Adjustment Expense, Undiscounted and Net of Reinsurance including ADC, All Accident Years	(11)
UK/Europe Casualty and Financial lines
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	14,600
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 7,339
Year 1 (as a percent)	5.30%
Year 2 (as a percent)	13.40%
Year 3 (as a percent)	10.90%
Year 4 (as a percent)	10.30%
Year 5 (as a percent)	9.00%
Year 6 (as a percent)	9.10%
Year 7 (as a percent)	5.70%
Year 8 (as a percent)	5.70%
Year 9 (as a percent)	3.30%
Year 10 (as a percent)	3.20%
UK/Europe Casualty and Financial lines | 2016
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	$ 1,819	1,766	1,687	1,686	1,674	1,685	1,566	1,561	1,482	1,392
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 194
Cumulative Number of Reported Claims | claim	142,980
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,418	1,359	1,316	1,221	1,108	975	812	616	399	125
UK/Europe Casualty and Financial lines | 2017
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,533	1,520	1,473	1,434	1,449	1,418	1,310	1,349	1,423
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 162
Cumulative Number of Reported Claims | claim	150,034
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,180	1,115	1,007	938	789	631	471	295	102
UK/Europe Casualty and Financial lines | 2018
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,849	1,831	1,742	1,696	1,600	1,569	1,465	1,413
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 263
Cumulative Number of Reported Claims | claim	151,989
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,365	1,275	1,179	944	778	599	392	120
UK/Europe Casualty and Financial lines | 2019
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,480	1,417	1,407	1,420	1,404	1,554	1,297
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 243
Cumulative Number of Reported Claims | claim	143,228
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,023	920	797	691	504	325	103
UK/Europe Casualty and Financial lines | 2020
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,180	1,215	1,266	1,278	1,338	1,319
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 252
Cumulative Number of Reported Claims | claim	86,594
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 720	630	533	385	239	63
UK/Europe Casualty and Financial lines | 2021
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,304	1,357	1,398	1,404	1,443
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 458
Cumulative Number of Reported Claims | claim	78,019
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 610	474	361	244	54
UK/Europe Casualty and Financial lines | 2022
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,293	1,279	1,320	1,370
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 621
Cumulative Number of Reported Claims | claim	75,486
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 404	310	195	60
UK/Europe Casualty and Financial lines | 2023
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,364	1,337	1,361
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 741
Cumulative Number of Reported Claims | claim	71,761
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 335	200	38
UK/Europe Casualty and Financial lines | 2024
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,428	1,389
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 919
Cumulative Number of Reported Claims | claim	73,433
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 222	63
UK/Europe Casualty and Financial lines | 2025
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,350
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 1,132
Cumulative Number of Reported Claims | claim	61,557
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 62
UK/Europe Casualty and Financial lines | Accident Years prior to 2016
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	1,027
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	7
UK/Europe Casualty and Financial lines | Short Duration Insurance Contracts Last Ten Accident Years
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	7,261
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	139
UK/Europe Casualty and Financial lines | All Accident Years
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	8,288
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	146
Prior Year Development for Unallocated Loss Adjustment Expense, Undiscounted and Net of Reinsurance including ADC, All Accident Years	70
Prior Year Development for Loss and Loss Adjustment Expense, Undiscounted and Net of Reinsurance including ADC, All Accident Years	216
UK/Europe Property and Special Risks
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	12,971
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 10,885
Year 1 (as a percent)	20.10%
Year 2 (as a percent)	36.70%
Year 3 (as a percent)	18.70%
Year 4 (as a percent)	15.00%
Year 5 (as a percent)	4.00%
Year 6 (as a percent)	3.20%
Year 7 (as a percent)	0.80%
Year 8 (as a percent)	0.00%
Year 9 (as a percent)	0.40%
Year 10 (as a percent)	(0.30%)
UK/Europe Property and Special Risks | 2016
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	$ 1,629	1,651	1,659	1,663	1,727	1,733	1,737	1,762	1,740	1,645
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 17
Cumulative Number of Reported Claims | claim	57,394
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,616	1,621	1,618	1,643	1,625	1,596	1,550	1,412	1,154	472
UK/Europe Property and Special Risks | 2017
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,601	1,604	1,603	1,605	1,639	1,654	1,648	1,674	1,671
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ (2)
Cumulative Number of Reported Claims | claim	53,611
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,529	1,518	1,512	1,497	1,458	1,399	1,255	968	363
UK/Europe Property and Special Risks | 2018
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,491	1,500	1,514	1,514	1,567	1,580	1,605	1,678
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 7
Cumulative Number of Reported Claims | claim	44,446
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,424	1,407	1,382	1,347	1,331	1,199	1,008	326
UK/Europe Property and Special Risks | 2019
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,112	1,130	1,126	1,122	1,132	1,133	1,172
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 54
Cumulative Number of Reported Claims | claim	34,054
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,007	1,013	981	935	846	672	273
UK/Europe Property and Special Risks | 2020
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,224	1,242	1,247	1,224	1,264	1,324
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ (2)
Cumulative Number of Reported Claims | claim	26,576
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,131	1,048	934	836	683	254
UK/Europe Property and Special Risks | 2021
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	972	987	962	1,011	1,048
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 69
Cumulative Number of Reported Claims | claim	23,384
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 809	779	711	519	194
UK/Europe Property and Special Risks | 2022
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,288	1,282	1,308	1,150
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 272
Cumulative Number of Reported Claims | claim	25,559
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,866	1,145	684	198
UK/Europe Property and Special Risks | 2023
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,060	1,086	1,090
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 135
Cumulative Number of Reported Claims | claim	24,666
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 744	537	161
UK/Europe Property and Special Risks | 2024
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,260	1,177
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 189
Cumulative Number of Reported Claims | claim	24,338
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 554	206
UK/Europe Property and Special Risks | 2025
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,334
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 585
Cumulative Number of Reported Claims | claim	17,987
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 205
UK/Europe Property and Special Risks | Accident Years prior to 2016
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	90
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	(9)
UK/Europe Property and Special Risks | Short Duration Insurance Contracts Last Ten Accident Years
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	2,086
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	(22)
UK/Europe Property and Special Risks | All Accident Years
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	2,176
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	(31)
Prior Year Development for Unallocated Loss Adjustment Expense, Undiscounted and Net of Reinsurance including ADC, All Accident Years	17
Prior Year Development for Loss and Loss Adjustment Expense, Undiscounted and Net of Reinsurance including ADC, All Accident Years	(14)
UK/Europe and Japan Personal Insurance
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	17,828
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 16,632
Year 1 (as a percent)	59.00%
Year 2 (as a percent)	25.90%
Year 3 (as a percent)	6.90%
Year 4 (as a percent)	3.30%
Year 5 (as a percent)	1.70%
Year 6 (as a percent)	1.30%
Year 7 (as a percent)	0.60%
Year 8 (as a percent)	0.30%
Year 9 (as a percent)	0.30%
Year 10 (as a percent)	0.00%
UK/Europe and Japan Personal Insurance | 2016
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	$ 2,128	2,127	2,131	2,130	2,137	2,140	2,143	2,147	2,140	2,146
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 2
Cumulative Number of Reported Claims | claim	1,794,526
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 2,117	2,116	2,111	2,106	2,091	2,066	2,021	1,935	1,760	$ 1,175
UK/Europe and Japan Personal Insurance | 2017
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	2,032	2,028	2,032	2,022	2,039	2,022	2,027	2,041	2,064
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 5
Cumulative Number of Reported Claims | claim	1,719,905
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 2,010	2,003	1,993	1,995	1,974	1,939	1,871	1,718	$ 1,153
UK/Europe and Japan Personal Insurance | 2018
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	2,305	2,306	2,317	2,317	2,295	2,323	2,329	2,423
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ (1)
Cumulative Number of Reported Claims | claim	1,918,168
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 2,293	2,286	2,267	2,219	2,178	2,099	1,946	$ 1,448
UK/Europe and Japan Personal Insurance | 2019
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,884	1,885	1,879	1,888	1,899	1,936	1,981
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 2
Cumulative Number of Reported Claims | claim	1,677,776
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,864	1,849	1,828	1,806	1,746	1,628	$ 1,156
UK/Europe and Japan Personal Insurance | 2020
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,603	1,603	1,613	1,627	1,683	1,815
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 2
Cumulative Number of Reported Claims | claim	1,394,864
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,576	1,560	1,533	1,496	1,396	$ 969
UK/Europe and Japan Personal Insurance | 2021
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,612	1,611	1,613	1,638	1,687
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 11
Cumulative Number of Reported Claims | claim	1,396,679
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,543	1,518	1,457	1,352	$ 952
UK/Europe and Japan Personal Insurance | 2022
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,742	1,747	1,809	1,788
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 19
Cumulative Number of Reported Claims | claim	2,079,335
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,654	1,600	1,485	$ 1,038
UK/Europe and Japan Personal Insurance | 2023
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,566	1,578	1,607
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 36
Cumulative Number of Reported Claims | claim	1,456,046
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,437	1,329	$ 906
UK/Europe and Japan Personal Insurance | 2024
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,511	1,514
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 41
Cumulative Number of Reported Claims | claim	1,422,120
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,278	$ 872
UK/Europe and Japan Personal Insurance | 2025
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred losses and allocated loss adjustment expenses, undiscounted and net of reinsurance	1,445
Total of IBNR Liabilities Plus Expected Development on Reported Losses	$ 217
Cumulative Number of Reported Claims | claim	1,221,216
Cumulative Paid Losses and Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 860
UK/Europe and Japan Personal Insurance | Accident Years prior to 2016
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	44
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	0
UK/Europe and Japan Personal Insurance | Short Duration Insurance Contracts Last Ten Accident Years
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	1,196
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	(16)
UK/Europe and Japan Personal Insurance | All Accident Years
Liability for Claims and Claims Adjustment Expense [Line Items]
Liabilities for losses and loss adjustment expenses and prior year development before accident year 2016, net of reinsurance	1,240
Liabilities for losses and loss adjustment expenses and prior year loss development, net of reinsurance	(16)
Prior Year Development for Unallocated Loss Adjustment Expense, Undiscounted and Net of Reinsurance including ADC, All Accident Years	53
Prior Year Development for Loss and Loss Adjustment Expense, Undiscounted and Net of Reinsurance including ADC, All Accident Years	$ 37