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Reserve for Unpaid Losses and Loss Adjustment Expenses - Historical Loss Development Triangles, P&C (Details) claim in Millions, $ in Millions	Dec. 31, 2022 USD ($) claim	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Workers’ compensation | Segment Reconciling Items
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 17,911
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	9,516
Workers’ compensation | 2013
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,809	$ 1,811	$ 1,831	$ 1,850	$ 1,861	$ 1,861	$ 1,883	$ 1,920	$ 1,981	$ 2,020
IBNR Reserves	$ 337
Claims Reported | claim	151,592
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,382	1,361	1,339	1,304	1,260	1,175	1,071	917	675	304
Workers’ compensation | 2014
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,637	1,654	1,679	1,692	1,713	1,761	1,789	1,838	1,869
IBNR Reserves	$ 353
Claims Reported | claim	126,371
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,191	1,167	1,137	1,099	1,041	960	811	598	275
Workers’ compensation | 2015
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,645	1,667	1,699	1,714	1,724	1,801	1,835	1,873
IBNR Reserves	$ 376
Claims Reported | claim	114,224
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,151	1,117	1,068	1,004	909	778	576	261
Workers’ compensation | 2016
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,670	1,708	1,748	1,767	1,780	1,772	1,772
IBNR Reserves	$ 419
Claims Reported | claim	112,486
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,110	1,064	1,003	908	779	579	255
Workers’ compensation | 2017
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,665	1,757	1,822	1,840	1,869	1,862
IBNR Reserves	$ 504
Claims Reported | claim	112,070
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,035	977	900	778	575	261
Workers’ compensation | 2018
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,870	1,904	1,915	1,917	1,916
IBNR Reserves	$ 608
Claims Reported | claim	119,284
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,090	983	837	624	283
Workers’ compensation | 2019
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,934	1,934	1,935	1,937
IBNR Reserves	$ 722
Claims Reported | claim	120,104
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,007	856	637	291
Workers’ compensation | 2020
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,849	1,864	1,865
IBNR Reserves	$ 937
Claims Reported | claim	91,187
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 695	507	223
Workers’ compensation | Short-Duration Insurance Contract, Accident Year 2021 [Member]
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,832	1,831
IBNR Reserves	$ 1,012
Claims Reported | claim	100,954
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 562	254
Workers’ compensation | Short-Duration Insurance Contract, Accident Year 2022
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	2,000
IBNR Reserves	$ 1,414
Claims Reported | claim	105,013
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 293
General liability | Segment Reconciling Items
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	7,509
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	3,486
General liability | 2013
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	503	500	508	505	502	488	484	456	442	455
IBNR Reserves	$ 36
Claims Reported | claim	15,217
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 457	442	422	398	372	320	233	141	53	13
General liability | 2014
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	510	505	515	522	513	494	481	475	506
IBNR Reserves	$ 50
Claims Reported | claim	16,445
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 437	423	402	358	304	214	130	42	15
General liability | 2015
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	647	637	647	633	594	554	560	556
IBNR Reserves	$ 67
Claims Reported | claim	16,621
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 547	524	477	409	278	156	55	10
General liability | 2016
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	636	620	632	632	607	583	613
IBNR Reserves	$ 58
Claims Reported | claim	17,666
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 513	446	368	283	131	52	12
General liability | 2017
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	615	613	615	613	614	626
IBNR Reserves	$ 105
Claims Reported | claim	17,168
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 441	344	255	156	67	15
General liability | 2018
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	728	703	697	669	692
IBNR Reserves	$ 212
Claims Reported | claim	18,502
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 409	288	177	83	21
General liability | 2019
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	840	822	827	822
IBNR Reserves	$ 379
Claims Reported | claim	17,914
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 339	192	100	29
General liability | 2020
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	923	923	938
IBNR Reserves	$ 625
Claims Reported | claim	13,204
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 202	110	45
General liability | Short-Duration Insurance Contract, Accident Year 2021 [Member]
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	991	1,002
IBNR Reserves	$ 804
Claims Reported | claim	10,791
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 115	34
General liability | Short-Duration Insurance Contract, Accident Year 2022
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,116
IBNR Reserves	$ 1,045
Claims Reported | claim	8,186
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 26
Marine [Member] | Segment Reconciling Items
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,476
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,192
Marine [Member] | 2013
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	137	137	138	136	133	138	134	133	151	147
IBNR Reserves	$ (2)
Claims Reported | claim	7,362
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 133	132	131	124	119	117	110	99	81	41
Marine [Member] | 2014
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	167	168	164	166	161	162	155	158	162
IBNR Reserves	$ 3
Claims Reported | claim	7,493
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 162	159	157	154	149	129	115	80	40
Marine [Member] | 2015
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	140	137	136	131	146	144	144	157
IBNR Reserves	$ 1
Claims Reported | claim	10,353
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 140	139	138	132	124	114	84	39
Marine [Member] | 2016
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	146	144	147	145	136	141	138
IBNR Reserves	$ (15)
Claims Reported | claim	13,592
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 141	138	130	120	104	79	35
Marine [Member] | 2017
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	180	177	171	172	185	159
IBNR Reserves	$ (5)
Claims Reported | claim	16,109
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 172	160	151	140	109	47
Marine [Member] | 2018
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	165	159	152	159	143
IBNR Reserves	$ (16)
Claims Reported | claim	14,165
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 154	146	137	103	36
Marine [Member] | 2019
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	134	139	141	143
IBNR Reserves	$ 3
Claims Reported | claim	8,562
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 110	100	82	35
Marine [Member] | 2020
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	137	141	149
IBNR Reserves	$ 12
Claims Reported | claim	5,019
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 90	68	31
Marine [Member] | Short-Duration Insurance Contract, Accident Year 2021 [Member]
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	128	129
IBNR Reserves	$ 40
Claims Reported | claim	4,847
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 63	25
Marine [Member] | Short-Duration Insurance Contract, Accident Year 2022
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	142
IBNR Reserves	$ 83
Claims Reported | claim	3,549
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 27
Package business | Segment Reconciling Items
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	7,218
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	5,288
Package business | 2013
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	582	583	587	586	592	586	585	573	565	579
IBNR Reserves	$ 20
Claims Reported | claim	43,716
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 556	552	549	541	522	504	467	414	339	225
Package business | 2014
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	576	581	593	603	603	602	601	578	566
IBNR Reserves	$ 24
Claims Reported | claim	43,483
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 545	542	535	525	507	468	416	345	226
Package business | 2015
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	564	567	581	588	583	585	588	582
IBNR Reserves	$ 22
Claims Reported | claim	42,330
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 530	513	505	486	445	383	332	212
Package business | 2016
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	591	595	611	625	632	638	655
IBNR Reserves	$ 36
Claims Reported | claim	44,224
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 540	521	500	465	410	353	225
Package business | 2017
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	637	644	657	692	702	695
IBNR Reserves	$ 48
Claims Reported | claim	46,771
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 561	534	496	447	372	235
Package business | 2018
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	655	667	688	724	719
IBNR Reserves	$ 78
Claims Reported | claim	45,088
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 537	498	451	402	237
Package business | 2019
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	744	749	769	813
IBNR Reserves	$ 116
Claims Reported | claim	43,573
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 571	488	413	254
Package business | 2020
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	877	893	915
IBNR Reserves	$ 245
Claims Reported | claim	62,208
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 573	493	326
Package business | Short-Duration Insurance Contract, Accident Year 2021 [Member]
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	954	946
IBNR Reserves	$ 309
Claims Reported | claim	46,012
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 556	368
Package business | Short-Duration Insurance Contract, Accident Year 2022
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,038
IBNR Reserves	$ 532
Claims Reported | claim	37,966
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 319
Property | P&C Commercial Lines | Segment Reconciling Items
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	3,922
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	3,383
Property | P&C Commercial Lines | 2013
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	247	247	247	247	247	249	252	254	252	267
IBNR Reserves	$ 0
Claims Reported | claim	21,690
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 244	244	245	245	244	242	243	238	223	161
Property | P&C Commercial Lines | 2014
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	279	279	280	280	279	279	282	281	293
IBNR Reserves	$ (1)
Claims Reported | claim	21,119
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 280	280	279	279	279	279	270	250	170
Property | P&C Commercial Lines | 2015
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	301	301	303	305	301	302	301	298
IBNR Reserves	$ 1
Claims Reported | claim	21,143
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 301	301	303	301	295	284	257	178
Property | P&C Commercial Lines | 2016
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	404	407	407	405	398	418	405
IBNR Reserves	$ 0
Claims Reported | claim	24,085
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 405	405	400	394	377	341	214
Property | P&C Commercial Lines | 2017
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	437	440	438	455	515	576
IBNR Reserves	$ 2
Claims Reported | claim	24,719
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 438	432	426	411	377	228
Property | P&C Commercial Lines | 2018
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	400	403	423	436	450
IBNR Reserves	$ 4
Claims Reported | claim	21,907
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 393	385	378	344	187
Property | P&C Commercial Lines | 2019
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	420	418	439	480
IBNR Reserves	$ (3)
Claims Reported | claim	21,098
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 405	383	351	215
Property | P&C Commercial Lines | 2020
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	439	468	501
IBNR Reserves	$ 64
Claims Reported | claim	20,511
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 355	336	221
Property | P&C Commercial Lines | Short-Duration Insurance Contract, Accident Year 2021 [Member]
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	499	530
IBNR Reserves	$ 74
Claims Reported | claim	18,188
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 382	241
Property | P&C Commercial Lines | Short-Duration Insurance Contract, Accident Year 2022
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	496
IBNR Reserves	$ 183
Claims Reported | claim	15,326
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 180
Automobile liability | P&C Commercial Lines | Segment Reconciling Items
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	4,025
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	2,824
Automobile liability | P&C Commercial Lines | 2013
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	332	333	334	336	339	340	341	334	318	311
IBNR Reserves	$ 5
Claims Reported | claim	34,172
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 326	324	323	320	311	295	259	202	130	62
Automobile liability | P&C Commercial Lines | 2014
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	332	332	333	334	341	337	331	317	309
IBNR Reserves	$ 5
Claims Reported | claim	30,096
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 325	320	318	309	299	252	197	131	59
Automobile liability | P&C Commercial Lines | 2015
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	358	360	359	356	356	372	358	308
IBNR Reserves	$ 7
Claims Reported | claim	28,587
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 348	344	335	314	267	207	142	62
Automobile liability | P&C Commercial Lines | 2016
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	395	395	391	391	390	393	385
IBNR Reserves	$ 7
Claims Reported | claim	29,201
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 379	357	339	303	232	147	65
Automobile liability | P&C Commercial Lines | 2017
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	394	381	383	379	383	372
IBNR Reserves	$ 4
Claims Reported | claim	26,384
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 368	328	285	211	134	60
Automobile liability | P&C Commercial Lines | 2018
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	424	406	405	396	349
IBNR Reserves	$ 27
Claims Reported | claim	24,733
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 360	305	238	153	62
Automobile liability | P&C Commercial Lines | 2019
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	460	450	439	425
IBNR Reserves	$ 61
Claims Reported | claim	28,473
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 327	247	160	67
Automobile liability | P&C Commercial Lines | 2020
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	419	424	428
IBNR Reserves	$ 149
Claims Reported | claim	21,963
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 200	119	55
Automobile liability | P&C Commercial Lines | Short-Duration Insurance Contract, Accident Year 2021 [Member]
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	443	440
IBNR Reserves	$ 252
Claims Reported | claim	19,623
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 127	55
Automobile liability | P&C Commercial Lines | Short-Duration Insurance Contract, Accident Year 2022
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	468
IBNR Reserves	$ 341
Claims Reported | claim	17,849
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 64
Automobile liability | P&C Personal Lines | Segment Reconciling Items
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	10,887
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	9,584
Automobile liability | P&C Personal Lines | 2013
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,155	1,155	1,156	1,157	1,153	1,152	1,153	1,144	1,145	1,131
IBNR Reserves	$ 5
Claims Reported | claim	205,487
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,149	1,148	1,144	1,142	1,135	1,121	1,091	1,002	816	442
Automobile liability | P&C Personal Lines | 2014
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,199	1,199	1,201	1,202	1,199	1,200	1,198	1,153	1,146
IBNR Reserves	$ 5
Claims Reported | claim	209,024
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,192	1,190	1,186	1,182	1,165	1,125	1,032	843	430
Automobile liability | P&C Personal Lines | 2015
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,320	1,324	1,328	1,331	1,330	1,338	1,340	1,195
IBNR Reserves	$ 3
Claims Reported | claim	216,901
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,313	1,310	1,304	1,292	1,243	1,142	935	475
Automobile liability | P&C Personal Lines | 2016
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,384	1,386	1,395	1,397	1,393	1,402	1,407
IBNR Reserves	$ 5
Claims Reported | claim	215,855
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,373	1,363	1,345	1,308	1,188	968	505
Automobile liability | P&C Personal Lines | 2017
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,198	1,200	1,214	1,228	1,275	1,277
IBNR Reserves	$ 9
Claims Reported | claim	187,545
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,180	1,161	1,123	1,033	836	441
Automobile liability | P&C Personal Lines | 2018
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,056	1,058	1,072	1,104	1,108
IBNR Reserves	$ 28
Claims Reported | claim	156,258
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 1,011	965	888	710	359
Automobile liability | P&C Personal Lines | 2019
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	986	991	1,010	1,018
IBNR Reserves	$ 52
Claims Reported | claim	139,641
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 897	816	654	323
Automobile liability | P&C Personal Lines | 2020
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	775	782	805
IBNR Reserves	$ 106
Claims Reported | claim	96,438
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 615	486	238
Automobile liability | P&C Personal Lines | Short-Duration Insurance Contract, Accident Year 2021 [Member]
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	886	881
IBNR Reserves	$ 224
Claims Reported | claim	100,945
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 553	247
Automobile liability | P&C Personal Lines | Short-Duration Insurance Contract, Accident Year 2022
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	928
IBNR Reserves	$ 423
Claims Reported | claim	99,686
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 301
Commercial automobile physical damage | P&C Commercial Lines | Segment Reconciling Items
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	181
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	169
Commercial automobile physical damage | P&C Commercial Lines | 2020
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	50	51	51
IBNR Reserves	$ 1
Claims Reported | claim	14,727
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 49	50	45
Commercial automobile physical damage | P&C Commercial Lines | Short-Duration Insurance Contract, Accident Year 2021 [Member]
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	62	58
IBNR Reserves	$ 1
Claims Reported | claim	15,436
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 61	51
Commercial automobile physical damage | P&C Commercial Lines | Short-Duration Insurance Contract, Accident Year 2022
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	69
IBNR Reserves	$ 4
Claims Reported | claim	15,100
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 59
Professional liability | Segment Reconciling Items
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	2,609
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,403
Professional liability | 2013
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	165	168	170	171	173	173	174	186	195	207
IBNR Reserves	$ 11
Claims Reported | claim	5,983
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 148	147	142	137	131	116	87	67	44	10
Professional liability | 2014
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	168	172	181	181	178	177	181	183	187
IBNR Reserves	$ 9
Claims Reported | claim	6,740
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 150	145	146	134	130	107	74	38	7
Professional liability | 2015
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	195	198	205	212	189	179	174	164
IBNR Reserves	$ (3)
Claims Reported | claim	7,254
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 174	163	140	124	107	85	40	9
Professional liability | 2016
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	192	194	193	195	202	176	183
IBNR Reserves	$ 13
Claims Reported | claim	8,421
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 165	146	123	110	88	50	8
Professional liability | 2017
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	242	238	224	230	202	205
IBNR Reserves	$ 37
Claims Reported | claim	9,527
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 179	150	122	87	48	11
Professional liability | 2018
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	269	274	274	278	247
IBNR Reserves	$ 24
Claims Reported | claim	10,138
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 197	163	128	72	15
Professional liability | 2019
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	350	333	315	297
IBNR Reserves	$ 115
Claims Reported | claim	9,809
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 199	148	77	21
Professional liability | 2020
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	337	364	369
IBNR Reserves	$ 185
Claims Reported | claim	7,945
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 118	71	19
Professional liability | Short-Duration Insurance Contract, Accident Year 2021 [Member]
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	343	339
IBNR Reserves	$ 262
Claims Reported | claim	6,728
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 55	15
Professional liability | Short-Duration Insurance Contract, Accident Year 2022
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	348
IBNR Reserves	$ 306
Claims Reported | claim	5,896
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 18
Bond | Segment Reconciling Items
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	635
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	260
Bond | 2013
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	29	34	34	35	39	49	48	55	58	64
IBNR Reserves	$ 9
Claims Reported | claim	1,470
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 20	20	20	20	19	19	19	17	9	3
Bond | 2014
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	64	60	60	59	59	67	66	67	71
IBNR Reserves	$ 12
Claims Reported | claim	1,389
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 52	47	46	44	43	43	40	31	18
Bond | 2015
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	42	47	48	54	60	63	67	67
IBNR Reserves	$ 17
Claims Reported | claim	1,404
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 25	30	32	34	31	24	20	9
Bond | 2016
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	37	45	51	55	61	61	61
IBNR Reserves	$ 16
Claims Reported | claim	1,341
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 22	22	22	20	15	12	2
Bond | 2017
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	70	79	94	101	90	63
IBNR Reserves	$ 26
Claims Reported | claim	1,775
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 43	42	54	55	46	5
Bond | 2018
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	70	71	72	68	68
IBNR Reserves	$ 40
Claims Reported | claim	1,714
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 29	24	23	16	6
Bond | 2019
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	73	74	73	72
IBNR Reserves	$ 57
Claims Reported | claim	1,860
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 16	15	13	3
Bond | 2020
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	79	84	83
IBNR Reserves	$ 54
Claims Reported | claim	2,101
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 21	12	4
Bond | Short-Duration Insurance Contract, Accident Year 2021 [Member]
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	85	85
IBNR Reserves	$ 67
Claims Reported | claim	2,561
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 21	8
Bond | Short-Duration Insurance Contract, Accident Year 2022
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	86
IBNR Reserves	$ 73
Claims Reported | claim	1,991
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 11
Assumed Reinsurance [Member] | Segment Reconciling Items
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,541
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,133
Assumed Reinsurance [Member] | 2013
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	103	103	103	103	102	102	105	102	119	115
IBNR Reserves	$ 0
Claims Reported | claim	1,668
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 103	103	102	102	101	100	98	91	83	53
Assumed Reinsurance [Member] | 2014
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	115	115	116	116	115	118	121	142	119
IBNR Reserves	$ (1)
Claims Reported | claim	1,814
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 115	115	114	113	112	109	106	119	66
Assumed Reinsurance [Member] | 2015
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	95	95	96	95	94	94	91	102
IBNR Reserves	$ 0
Claims Reported | claim	1,585
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 95	94	93	91	83	77	64	42
Assumed Reinsurance [Member] | 2016
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	102	101	101	100	98	90	88
IBNR Reserves	$ (5)
Claims Reported | claim	1,766
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 98	97	95	90	84	66	36
Assumed Reinsurance [Member] | 2017
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	155	152	156	161	153	129
IBNR Reserves	$ (2)
Claims Reported | claim	2,213
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 149	147	144	135	116	44
Assumed Reinsurance [Member] | 2018
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	135	133	128	126	128
IBNR Reserves	$ (14)
Claims Reported | claim	2,412
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 141	138	132	111	25
Assumed Reinsurance [Member] | 2019
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	189	185	188	181
IBNR Reserves	$ 19
Claims Reported | claim	2,804
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 158	152	131	62
Assumed Reinsurance [Member] | 2020
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	186	180	183
IBNR Reserves	$ 55
Claims Reported | claim	2,157
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 113	89	49
Assumed Reinsurance [Member] | Short-Duration Insurance Contract, Accident Year 2021 [Member]
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	195	191
IBNR Reserves	$ 49
Claims Reported | claim	1,484
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 101	46
Assumed Reinsurance [Member] | Short-Duration Insurance Contract, Accident Year 2022
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	266
IBNR Reserves	$ 154
Claims Reported | claim	712
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 60
Personal automobile physical damage | Segment Reconciling Items
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,288
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	1,250
Personal automobile physical damage | 2020
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	342	346	349
IBNR Reserves	$ 1
Claims Reported | claim	211,066
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 341	341	333
Personal automobile physical damage | Short-Duration Insurance Contract, Accident Year 2021 [Member]
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	413	412
IBNR Reserves	$ 2
Claims Reported | claim	225,425
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 411	388
Personal automobile physical damage | Short-Duration Insurance Contract, Accident Year 2022
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	533
IBNR Reserves	$ (5)
Claims Reported | claim	224,117
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 498
Homeowners | Segment Reconciling Items
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	6,063
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	5,728
Homeowners | 2013
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	629	629	630	629	630	632	634	637	638	673
IBNR Reserves	$ 1
Claims Reported | claim	113,556
Homeowners | 2014
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 698	698	698	698	698	700	702	707	710
IBNR Reserves	$ 0
Claims Reported | claim	121,927
Homeowners | 2015
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 684	684	684	684	684	690	703	690
IBNR Reserves	$ 1
Claims Reported | claim	120,010
Homeowners | 2016
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 658	658	658	658	663	673	669
IBNR Reserves	$ 1
Claims Reported | claim	119,810
Homeowners | 2017
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 774	775	783	884	889	866
IBNR Reserves	$ 7
Claims Reported | claim	124,761
Homeowners | 2018
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 639	642	673	910	903
IBNR Reserves	$ (1)
Claims Reported | claim	102,870
Homeowners | 2019
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 468	470	475	501
IBNR Reserves	$ 6
Claims Reported | claim	84,721
Homeowners | 2020
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 513	512	525
IBNR Reserves	$ 20
Claims Reported | claim	88,347
Homeowners | Short-Duration Insurance Contract, Accident Year 2021 [Member]
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 501	502
IBNR Reserves	$ 28
Claims Reported | claim	76,720
Homeowners | Short-Duration Insurance Contract, Accident Year 2022
Claims Development [Line Items]
Incurred Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 499
IBNR Reserves	$ 113
Claims Reported | claim	57,936
Homeowners | P&C Personal Lines | Segment Reconciling Items
Claims Development [Line Items]
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 5,728
Homeowners | P&C Personal Lines | 2013
Claims Development [Line Items]
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	629	628	628	628	627	626	622	611	590	$ 467
Homeowners | P&C Personal Lines | 2014
Claims Development [Line Items]
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	698	698	697	697	695	691	684	663	$ 526
Homeowners | P&C Personal Lines | 2015
Claims Development [Line Items]
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	682	681	681	680	674	665	645	$ 487
Homeowners | P&C Personal Lines | 2016
Claims Development [Line Items]
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	656	655	653	649	640	621	$ 481
Homeowners | P&C Personal Lines | 2017
Claims Development [Line Items]
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	762	761	757	795	747	$ 538
Homeowners | P&C Personal Lines | 2018
Claims Development [Line Items]
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	627	619	616	712	$ 484
Homeowners | P&C Personal Lines | 2019
Claims Development [Line Items]
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	458	445	425	$ 318
Homeowners | P&C Personal Lines | 2020
Claims Development [Line Items]
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	478	454	$ 335
Homeowners | P&C Personal Lines | Short-Duration Insurance Contract, Accident Year 2021 [Member]
Claims Development [Line Items]
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	440	$ 305
Homeowners | P&C Personal Lines | Short-Duration Insurance Contract, Accident Year 2022
Claims Development [Line Items]
Cumulative Paid Losses & Allocated Loss Adjustment Expenses, Net of Reinsurance	$ 298

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