Insurance - Short-duration insurance contracts, claims development (Details) - Property and casualty insurance $ in Millions		Dec. 31, 2018 USD ($) claim	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2011 USD ($)	Dec. 31, 2010 USD ($)	Dec. 31, 2009 USD ($)
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 19,905
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		14,960
Unpaid losses and LAE — 11th year and prior (excluding unallocated LAE)		561
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE)		5,506
Accident Year 2009
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		1,519	$ 1,529	$ 1,539	$ 1,543	$ 1,545	$ 1,552	$ 1,566	$ 1,596	$ 1,607	$ 1,624
Total IBNR Plus Expected Development on Reported Claims		$ 43
Cumulative Number of Reported Claims | claim		222,664
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 1,445	1,435	1,424	1,404	1,370	1,308	1,216	1,079	871	509
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[1]	95.10%
Accident Year 2010
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 1,676	1,690	1,698	1,698	1,710	1,690	1,705	1,710	1,724
Total IBNR Plus Expected Development on Reported Claims		$ 54
Cumulative Number of Reported Claims | claim		216,568
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 1,595	1,580	1,562	1,536	1,485	1,387	1,220	1,005	576
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[1]	95.20%
Accident Year 2011
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 1,843	1,859	1,866	1,861	1,871	1,849	1,848	1,840
Total IBNR Plus Expected Development on Reported Claims		$ 67
Cumulative Number of Reported Claims | claim		209,098
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 1,734	1,711	1,682	1,629	1,534	1,389	1,181	609
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[1]	94.10%
Accident Year 2012
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 1,906	1,941	1,955	1,947	1,946	1,952	1,970
Total IBNR Plus Expected Development on Reported Claims		$ 89
Cumulative Number of Reported Claims | claim		218,585
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 1,785	1,735	1,675	1,579	1,418	1,214	824
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[1]	93.70%
Accident Year 2013
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 1,982	2,000	1,996	2,000	2,011	2,036
Total IBNR Plus Expected Development on Reported Claims		$ 128
Cumulative Number of Reported Claims | claim		221,362
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 1,774	1,714	1,617	1,443	1,214	697
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[1]	89.50%
Accident Year 2014
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 2,004	2,038	2,040	2,050	2,083
Total IBNR Plus Expected Development on Reported Claims		$ 186
Cumulative Number of Reported Claims | claim		220,164
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 1,705	1,588	1,422	1,174	594
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[1]	85.10%
Accident Year 2015
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 2,038	2,041	2,047	2,114
Total IBNR Plus Expected Development on Reported Claims		$ 245
Cumulative Number of Reported Claims | claim		227,435
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 1,592	1,404	1,129	619
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[1]	78.10%
Accident Year 2016
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 2,082	2,083	2,117
Total IBNR Plus Expected Development on Reported Claims		$ 432
Cumulative Number of Reported Claims | claim		220,481
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 1,350	1,099	577
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[1]	64.80%
Accident Year 2017
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 2,348	2,375
Total IBNR Plus Expected Development on Reported Claims		$ 737
Cumulative Number of Reported Claims | claim		240,542
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 1,250	709
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[1]	53.20%
Accident Year 2018
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 2,507
Total IBNR Plus Expected Development on Reported Claims		$ 1,123
Cumulative Number of Reported Claims | claim		205,419
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 730
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[1]	29.10%
Excludes short-duration insurance contracts detail for accident years not separately presented
Claims Development [Line Items]
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE)		$ 4,945
Property and transportation
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		7,957
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		6,863
Unpaid losses and LAE — 11th year and prior (excluding unallocated LAE)		23
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE)		1,117
Property and transportation | Accident Year 2009
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		490	491	491	491	494	494	498	505	487	503
Total IBNR Plus Expected Development on Reported Claims		$ 2
Cumulative Number of Reported Claims | claim		138,248
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 485	484	481	480	476	462	440	397	333	219
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[2]	99.00%
Property and transportation | Accident Year 2010
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 657	659	661	657	656	654	646	640	680
Total IBNR Plus Expected Development on Reported Claims		$ 3
Cumulative Number of Reported Claims | claim		138,235
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 650	648	643	638	627	597	536	487	316
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[2]	98.90%
Property and transportation | Accident Year 2011
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 850	853	856	844	833	819	803	816
Total IBNR Plus Expected Development on Reported Claims		$ 6
Cumulative Number of Reported Claims | claim		139,345
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 839	836	828	810	777	732	670	367
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[2]	98.70%
Property and transportation | Accident Year 2012
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 897	900	905	892	880	866	875
Total IBNR Plus Expected Development on Reported Claims		$ 13
Cumulative Number of Reported Claims | claim		145,636
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 892	866	852	826	780	715	574
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[2]	99.40%
Property and transportation | Accident Year 2013
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 890	890	890	884	881	894
Total IBNR Plus Expected Development on Reported Claims		$ 18
Cumulative Number of Reported Claims | claim		141,293
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 859	843	814	769	710	440
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[2]	96.50%
Property and transportation | Accident Year 2014
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 831	834	831	842	856
Total IBNR Plus Expected Development on Reported Claims		$ 25
Cumulative Number of Reported Claims | claim		136,259
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 784	756	702	638	332
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[2]	94.30%
Property and transportation | Accident Year 2015
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 789	789	794	831
Total IBNR Plus Expected Development on Reported Claims		$ 36
Cumulative Number of Reported Claims | claim		134,484
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 717	675	587	361
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[2]	90.90%
Property and transportation | Accident Year 2016
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 733	730	762
Total IBNR Plus Expected Development on Reported Claims		$ 74
Cumulative Number of Reported Claims | claim		122,623
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 590	528	296
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[2]	80.50%
Property and transportation | Accident Year 2017
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 868	904
Total IBNR Plus Expected Development on Reported Claims		$ 128
Cumulative Number of Reported Claims | claim		140,963
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 648	383
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[2]	74.70%
Property and transportation | Accident Year 2018
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 952
Total IBNR Plus Expected Development on Reported Claims		$ 277
Cumulative Number of Reported Claims | claim		119,817
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 399
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[2]	41.90%
Property and transportation | Excludes short-duration insurance contracts detail for accident years not separately presented
Claims Development [Line Items]
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE)		$ 1,094
Specialty casualty
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		9,776
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		6,369
Unpaid losses and LAE — 11th year and prior (excluding unallocated LAE)		477
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE)		3,884
Specialty casualty | Accident Year 2009
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		811	820	824	829	828	833	844	864	887	888
Total IBNR Plus Expected Development on Reported Claims		$ 34
Cumulative Number of Reported Claims | claim		56,985
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 748	740	731	715	691	653	591	510	381	170
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[3]	92.20%
Specialty casualty | Accident Year 2010
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 853	864	867	868	879	865	887	886	870
Total IBNR Plus Expected Development on Reported Claims		$ 47
Cumulative Number of Reported Claims | claim		56,411
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 782	770	756	735	699	644	559	411	191
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[3]	91.70%
Specialty casualty | Accident Year 2011
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 811	819	822	827	842	833	845	847
Total IBNR Plus Expected Development on Reported Claims		$ 52
Cumulative Number of Reported Claims | claim		53,385
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 725	707	687	655	606	517	380	172
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[3]	89.40%
Specialty casualty | Accident Year 2012
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 838	867	872	876	876	883	890
Total IBNR Plus Expected Development on Reported Claims		$ 64
Cumulative Number of Reported Claims | claim		51,885
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 735	713	674	611	508	378	171
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[3]	87.70%
Specialty casualty | Accident Year 2013
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 913	933	928	933	938	956
Total IBNR Plus Expected Development on Reported Claims		$ 99
Cumulative Number of Reported Claims | claim		51,620
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 754	717	656	545	388	180
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[3]	82.60%
Specialty casualty | Accident Year 2014
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 966	992	994	994	1,023
Total IBNR Plus Expected Development on Reported Claims		$ 139
Cumulative Number of Reported Claims | claim		54,494
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 741	668	565	406	187
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[3]	76.70%
Specialty casualty | Accident Year 2015
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 1,030	1,031	1,033	1,068
Total IBNR Plus Expected Development on Reported Claims		$ 185
Cumulative Number of Reported Claims | claim		55,468
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 692	569	406	176
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[3]	67.20%
Specialty casualty | Accident Year 2016
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 1,097	1,108	1,115
Total IBNR Plus Expected Development on Reported Claims		$ 313
Cumulative Number of Reported Claims | claim		53,038
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 571	411	184
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[3]	52.10%
Specialty casualty | Accident Year 2017
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 1,200	1,196
Total IBNR Plus Expected Development on Reported Claims		$ 539
Cumulative Number of Reported Claims | claim		52,658
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 414	196
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[3]	34.50%
Specialty casualty | Accident Year 2018
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 1,257
Total IBNR Plus Expected Development on Reported Claims		$ 705
Cumulative Number of Reported Claims | claim		48,996
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 207
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[3]	16.50%
Specialty casualty | Excludes short-duration insurance contracts detail for accident years not separately presented
Claims Development [Line Items]
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE)		$ 3,407
Specialty financial
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		1,623
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		1,397
Unpaid losses and LAE — 11th year and prior (excluding unallocated LAE)		(1)
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE)		225
Specialty financial | Accident Year 2009
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		186	185	186	187	186	188	184	186	192	192
Total IBNR Plus Expected Development on Reported Claims		$ 1
Cumulative Number of Reported Claims | claim		27,431
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 185	186	186	185	181	171	166	157	145	112
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[4]	99.50%
Specialty financial | Accident Year 2010
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 126	127	130	133	135	132	132	145	138
Total IBNR Plus Expected Development on Reported Claims		$ 1
Cumulative Number of Reported Claims | claim		21,922
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 126	126	128	130	132	122	104	93	61
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[4]	100.00%
Specialty financial | Accident Year 2011
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 139	143	144	147	153	155	157	138
Total IBNR Plus Expected Development on Reported Claims		$ 6
Cumulative Number of Reported Claims | claim		16,368
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 132	131	131	130	123	115	111	58
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[4]	95.00%
Specialty financial | Accident Year 2012
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 132	135	137	139	151	163	163
Total IBNR Plus Expected Development on Reported Claims		$ 6
Cumulative Number of Reported Claims | claim		21,064
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 128	126	121	117	109	104	71
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[4]	97.00%
Specialty financial | Accident Year 2013
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 126	127	131	137	145	140
Total IBNR Plus Expected Development on Reported Claims		$ 9
Cumulative Number of Reported Claims | claim		28,449
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 117	117	113	107	100	70
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[4]	92.90%
Specialty financial | Accident Year 2014
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 147	153	156	157	146
Total IBNR Plus Expected Development on Reported Claims		$ 9
Cumulative Number of Reported Claims | claim		29,411
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 137	128	125	109	62
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[4]	93.20%
Specialty financial | Accident Year 2015
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 153	158	160	156
Total IBNR Plus Expected Development on Reported Claims		$ 16
Cumulative Number of Reported Claims | claim		37,483
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 133	129	110	72
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[4]	86.90%
Specialty financial | Accident Year 2016
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 187	184	179
Total IBNR Plus Expected Development on Reported Claims		$ 24
Cumulative Number of Reported Claims | claim		44,820
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 158	141	88
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[4]	84.50%
Specialty financial | Accident Year 2017
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 215	212
Total IBNR Plus Expected Development on Reported Claims		$ 34
Cumulative Number of Reported Claims | claim		46,921
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 169	120
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[4]	78.60%
Specialty financial | Accident Year 2018
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 212
Total IBNR Plus Expected Development on Reported Claims		$ 79
Cumulative Number of Reported Claims | claim		36,606
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 112
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[4]	52.80%
Specialty financial | Excludes short-duration insurance contracts detail for accident years not separately presented
Claims Development [Line Items]
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE)		$ 226
Other specialty
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		549
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		331
Unpaid losses and LAE — 11th year and prior (excluding unallocated LAE)		62
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE)		280
Other specialty | Accident Year 2009
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		32	33	38	36	37	37	40	41	41	41
Total IBNR Plus Expected Development on Reported Claims		$ 6
Cumulative Number of Reported Claims | claim	[5]	0
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 27	25	26	24	22	22	19	15	12	$ 8
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[6]	84.40%
Other specialty | Accident Year 2010
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 40	40	40	40	40	39	40	39	36
Total IBNR Plus Expected Development on Reported Claims		$ 3
Cumulative Number of Reported Claims | claim	[5]	0
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 37	36	35	33	27	24	21	14	$ 8
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[6]	92.50%
Other specialty | Accident Year 2011
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 43	44	44	43	43	42	43	39
Total IBNR Plus Expected Development on Reported Claims		$ 3
Cumulative Number of Reported Claims | claim	[5]	0
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 38	37	36	34	28	25	20	$ 12
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[6]	88.40%
Other specialty | Accident Year 2012
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 39	39	41	40	39	40	42
Total IBNR Plus Expected Development on Reported Claims		$ 6
Cumulative Number of Reported Claims | claim	[5]	0
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 30	30	28	25	21	17	$ 8
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[6]	76.90%
Other specialty | Accident Year 2013
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 53	50	47	46	47	46
Total IBNR Plus Expected Development on Reported Claims		$ 2
Cumulative Number of Reported Claims | claim	[5]	0
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 44	37	34	22	16	$ 7
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[6]	83.00%
Other specialty | Accident Year 2014
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 60	59	59	57	58
Total IBNR Plus Expected Development on Reported Claims		$ 13
Cumulative Number of Reported Claims | claim	[5]	0
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 43	36	30	21	$ 13
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[6]	71.70%
Other specialty | Accident Year 2015
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 66	63	60	59
Total IBNR Plus Expected Development on Reported Claims		$ 8
Cumulative Number of Reported Claims | claim	[5]	0
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 50	31	26	$ 10
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[6]	75.80%
Other specialty | Accident Year 2016
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 65	61	61
Total IBNR Plus Expected Development on Reported Claims		$ 21
Cumulative Number of Reported Claims | claim	[5]	0
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 31	19	$ 9
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[6]	47.70%
Other specialty | Accident Year 2017
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 65	63
Total IBNR Plus Expected Development on Reported Claims		$ 36
Cumulative Number of Reported Claims | claim	[5]	0
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 19	$ 10
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[6]	29.20%
Other specialty | Accident Year 2018
Claims Development [Line Items]
Incurred Claims and Allocated LAE, Net of Reinsurance		$ 86
Total IBNR Plus Expected Development on Reported Claims		$ 62
Cumulative Number of Reported Claims | claim	[5]	0
Cumulative Paid Claims and Allocated LAE, Net of Reinsurance		$ 12
Cumulative Percentage Paid of Incurred Claims and Allocated LAE, Net of Reinsurance	[6]	14.00%
Other specialty | Excludes short-duration insurance contracts detail for accident years not separately presented
Claims Development [Line Items]
Unpaid losses and LAE, net of reinsurance (excluding unallocated LAE)		$ 218

[1] Represents the cumulative percentage paid of incurred claims and allocated LAE (net of reinsurance, as estimated at December 31, 2018).

[2] Represents the cumulative percentage paid of incurred claims and allocated LAE (net of reinsurance, as estimated at December 31, 2018).

[3] Represents the cumulative percentage paid of incurred claims and allocated LAE (net of reinsurance, as estimated at December 31, 2018).

[4] Represents the cumulative percentage paid of incurred claims and allocated LAE (net of reinsurance, as estimated at December 31, 2018).

[5] The amounts shown in Other specialty represent business assumed by AFG’s internal reinsurance program from the operations that make up AFG’s other Specialty property and casualty insurance sub-segments. Accordingly, the liability for incurred claims and allocated LAE represents additional reserves held on claims counted in the tables provided for the other sub-segments (above).

[6] Represents the cumulative percentage paid of incurred claims and allocated LAE (net of reinsurance, as estimated at December 31, 2018).