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RESERVE FOR LOSSES AND LOSS EXPENSES - Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Claims Development [Line Items]
Liabilities for claims and claim adjustment expenses, net of reinsurance	$ 10,436,507
Insurance
Claims Development [Line Items]
Liabilities for claims and claim adjustment expenses, net of reinsurance	5,166,419
Insurance | Property
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	3,460,155
All outstanding liabilities before 2014, net of reinsurance	14,248
Liabilities for claims and claim adjustment expenses, net of reinsurance	662,936
Insurance | Property | Accident Year 2014
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	252,526	$ 252,787	$ 252,772	$ 251,701	$ 254,858	$ 254,051	$ 250,321	$ 244,372	$ 201,931	$ 100,736
Insurance | Property | Accident Year 2015
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	181,716	182,038	177,227	186,010	179,409	179,727	166,211	145,027	67,621
Insurance | Property | Accident Year 2016
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	260,115	253,891	256,476	250,822	250,662	243,050	206,979	82,583
Insurance | Property | Accident Year 2017
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	647,610	635,493	645,841	650,218	622,040	513,044	190,861
Insurance | Property | Accident Year 2018
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	577,000	590,739	573,034	563,191	468,431	221,345
Insurance | Property | Accident Year 2019
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	332,848	343,463	306,415	257,515	148,181
Insurance | Property | Accident Year 2020
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	531,448	481,646	425,893	182,611
Insurance | Property | Accident Year 2021
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	323,656	286,801	134,273
Insurance | Property | Accident Year 2022
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	262,381	97,622
Insurance | Property | Accident Year 2023
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	90,855
Insurance | Accident and health
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	816,331
All outstanding liabilities before 2014, net of reinsurance	(238)
Liabilities for claims and claim adjustment expenses, net of reinsurance	114,493
Insurance | Accident and health | Accident Year 2014
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	62,660	61,996	61,588	62,716	62,844	62,513	61,855	60,682	56,693	31,662
Insurance | Accident and health | Accident Year 2015
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	60,575	62,677	62,584	61,926	62,065	61,051	60,168	56,988	31,518
Insurance | Accident and health | Accident Year 2016
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	85,272	86,123	85,413	85,010	83,929	83,077	79,237	41,583
Insurance | Accident and health | Accident Year 2017
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	118,138	116,280	117,100	115,981	114,555	109,312	63,285
Insurance | Accident and health | Accident Year 2018
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	114,595	113,787	112,884	109,194	106,748	61,849
Insurance | Accident and health | Accident Year 2019
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	68,030	68,088	63,046	61,526	45,133
Insurance | Accident and health | Accident Year 2020
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	59,240	60,804	52,290	36,317
Insurance | Accident and health | Accident Year 2021
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	69,661	61,593	39,185
Insurance | Accident and health | Accident Year 2022
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	82,209	46,568
Insurance | Accident and health | Accident Year 2023
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	95,951
Insurance | Marine and aviation
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	1,230,094
All outstanding liabilities before 2014, net of reinsurance	13,750
Liabilities for claims and claim adjustment expenses, net of reinsurance	678,482
Insurance | Marine and aviation | Accident Year 2014
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	50,383	50,255	48,435	53,941	52,793	48,583	39,439	36,805	22,874	10,336
Insurance | Marine and aviation | Accident Year 2015
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	142,432	142,437	142,268	135,881	133,087	130,290	125,369	69,563	29,498
Insurance | Marine and aviation | Accident Year 2016
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	97,951	97,274	94,184	92,239	90,273	83,039	50,976	22,886
Insurance | Marine and aviation | Accident Year 2017
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	196,724	184,824	180,904	172,205	140,126	106,527	35,415
Insurance | Marine and aviation | Accident Year 2018
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	197,961	185,455	173,667	159,948	123,434	47,525
Insurance | Marine and aviation | Accident Year 2019
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	178,967	171,372	145,927	103,253	54,028
Insurance | Marine and aviation | Accident Year 2020
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	119,063	106,403	84,391	44,655
Insurance | Marine and aviation | Accident Year 2021
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	108,772	69,687	26,924
Insurance | Marine and aviation | Accident Year 2022
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	101,228	30,101
Insurance | Marine and aviation | Accident Year 2023
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	36,613
Insurance | Cyber
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	428,268
All outstanding liabilities before 2014, net of reinsurance	9,471
Liabilities for claims and claim adjustment expenses, net of reinsurance	322,071
Insurance | Cyber | Accident Year 2014
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	38,043	36,070	35,440	33,732	33,819	31,260	29,962	23,330	12,162	3,136
Insurance | Cyber | Accident Year 2015
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	45,432	43,635	42,515	39,470	30,865	28,501	25,544	15,333	5,572
Insurance | Cyber | Accident Year 2016
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	24,054	23,207	23,136	21,333	18,502	14,141	4,637	1,348
Insurance | Cyber | Accident Year 2017
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	39,995	40,557	38,031	35,897	28,331	19,165	9,354
Insurance | Cyber | Accident Year 2018
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	18,334	19,267	14,810	9,874	7,327	2,171
Insurance | Cyber | Accident Year 2019
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	57,318	60,961	32,608	20,950	2,787
Insurance | Cyber | Accident Year 2020
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	82,625	63,813	50,344	17,732
Insurance | Cyber | Accident Year 2021
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	75,369	65,577	24,108
Insurance | Cyber | Accident Year 2022
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	37,861	7,830
Insurance | Cyber | Accident Year 2023
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	9,237
Insurance | Professional lines
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	1,979,153
All outstanding liabilities before 2014, net of reinsurance	131,134
Liabilities for claims and claim adjustment expenses, net of reinsurance	1,930,348
Insurance | Professional lines | Accident Year 2014
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	253,033	244,776	238,969	216,811	206,982	190,560	160,677	105,155	57,536	20,263
Insurance | Professional lines | Accident Year 2015
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	249,916	225,062	213,465	200,892	171,000	139,574	111,149	51,709	14,353
Insurance | Professional lines | Accident Year 2016
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	290,732	276,175	235,136	210,701	172,360	131,831	66,048	14,428
Insurance | Professional lines | Accident Year 2017
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	291,943	269,668	198,859	167,645	109,107	51,823	11,515
Insurance | Professional lines | Accident Year 2018
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	336,329	265,501	204,941	143,248	74,859	18,446
Insurance | Professional lines | Accident Year 2019
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	289,475	206,462	133,453	76,711	25,061
Insurance | Professional lines | Accident Year 2020
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	125,713	97,847	44,076	8,729
Insurance | Professional lines | Accident Year 2021
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	83,605	38,605	9,781
Insurance | Professional lines | Accident Year 2022
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	46,224	10,983
Insurance | Professional lines | Accident Year 2023
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	12,183
Insurance | Credit and political risk
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	278,317
All outstanding liabilities before 2014, net of reinsurance	592
Liabilities for claims and claim adjustment expenses, net of reinsurance	125,355
Insurance | Credit and political risk | Accident Year 2014
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	69,677	69,677	70,224	70,224	64,050	57,857	57,857	61,108	39,952	1,924
Insurance | Credit and political risk | Accident Year 2015
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	23,309	23,309	23,309	23,309	23,309	23,309	23,309	23,309	0
Insurance | Credit and political risk | Accident Year 2016
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	24,885	24,885	24,885	24,885	24,885	24,885	24,885	0
Insurance | Credit and political risk | Accident Year 2017
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	8,666	10,394	10,925	11,710	9,251	4,035	403
Insurance | Credit and political risk | Accident Year 2018
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	23,841	19,963	11,851	15,517	13,488	5,370
Insurance | Credit and political risk | Accident Year 2019
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	55,067	56,956	53,750	46,456	16,026
Insurance | Credit and political risk | Accident Year 2020
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	53,786	58,492	90,299	9,825
Insurance | Credit and political risk | Accident Year 2021
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	8,228	(370)	2,769
Insurance | Credit and political risk | Accident Year 2022
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	8,115	2,796
Insurance | Credit and political risk | Accident Year 2023
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	2,743
Insurance | Liability
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	1,239,193
All outstanding liabilities before 2014, net of reinsurance	49,217
Liabilities for claims and claim adjustment expenses, net of reinsurance	1,332,734
Insurance | Liability | Accident Year 2014
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	116,384	113,150	106,205	103,041	93,569	84,369	71,589	49,829	18,633	1,411
Insurance | Liability | Accident Year 2015
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	162,656	159,004	150,640	140,809	120,136	92,598	39,581	22,353	5,438
Insurance | Liability | Accident Year 2016
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	102,773	95,787	79,519	66,290	56,403	36,356	23,260	6,315
Insurance | Liability | Accident Year 2017
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	190,475	168,615	143,440	115,568	58,988	29,432	5,463
Insurance | Liability | Accident Year 2018
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	188,910	158,622	119,152	72,219	34,860	9,374
Insurance | Liability | Accident Year 2019
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	192,435	139,077	83,692	39,846	7,833
Insurance | Liability | Accident Year 2020
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	118,306	75,907	25,174	8,148
Insurance | Liability | Accident Year 2021
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	103,892	51,859	13,397
Insurance | Liability | Accident Year 2022
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	53,507	13,212
Insurance | Liability | Accident Year 2023
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	9,855
Reinsurance
Claims Development [Line Items]
Liabilities for claims and claim adjustment expenses, net of reinsurance	5,270,088
Reinsurance | Accident and health
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	1,686,952
All outstanding liabilities before 2014, net of reinsurance	(213)
Liabilities for claims and claim adjustment expenses, net of reinsurance	194,150
Reinsurance | Accident and health | Accident Year 2014
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	87,202	86,771	86,384	87,302	86,622	86,534	86,332	85,931	79,974	36,571
Reinsurance | Accident and health | Accident Year 2015
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	92,468	93,735	93,921	92,497	92,036	91,935	88,728	77,316	23,409
Reinsurance | Accident and health | Accident Year 2016
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	189,409	189,815	188,836	189,234	187,251	181,072	149,959	50,046
Reinsurance | Accident and health | Accident Year 2017
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	179,889	180,121	179,462	178,943	172,111	157,157	79,252
Reinsurance | Accident and health | Accident Year 2018
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	195,018	194,524	191,400	191,832	165,323	72,899
Reinsurance | Accident and health | Accident Year 2019
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	194,800	196,694	195,954	169,608	67,810
Reinsurance | Accident and health | Accident Year 2020
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	192,491	210,665	172,178	81,875
Reinsurance | Accident and health | Accident Year 2021
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	210,115	179,626	68,652
Reinsurance | Accident and health | Accident Year 2022
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	214,611	101,596
Reinsurance | Accident and health | Accident Year 2023
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	130,949
Reinsurance | Marine and aviation
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	268,825
All outstanding liabilities before 2014, net of reinsurance	1,923
Liabilities for claims and claim adjustment expenses, net of reinsurance	138,264
Reinsurance | Marine and aviation | Accident Year 2014
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	8,477	7,563	7,370	7,003	6,499	6,320	5,256	4,388	2,307	1,121
Reinsurance | Marine and aviation | Accident Year 2015
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	11,058	10,925	10,843	11,017	10,220	8,662	6,443	2,665	416
Reinsurance | Marine and aviation | Accident Year 2016
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	35,256	35,044	34,450	33,399	30,619	26,673	19,544	2,765
Reinsurance | Marine and aviation | Accident Year 2017
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	37,996	37,091	36,978	33,912	28,954	23,620	2,803
Reinsurance | Marine and aviation | Accident Year 2018
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	37,829	34,435	30,763	24,325	10,880	1,783
Reinsurance | Marine and aviation | Accident Year 2019
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	67,800	52,763	34,317	27,167	10,763
Reinsurance | Marine and aviation | Accident Year 2020
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	29,862	24,006	16,730	4,024
Reinsurance | Marine and aviation | Accident Year 2021
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	20,486	12,341	5,478
Reinsurance | Marine and aviation | Accident Year 2022
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	18,588	7,817
Reinsurance | Marine and aviation | Accident Year 2023
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	1,473
Reinsurance | Professional lines
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	989,284
All outstanding liabilities before 2014, net of reinsurance	113,403
Liabilities for claims and claim adjustment expenses, net of reinsurance	1,054,117
Reinsurance | Professional lines | Accident Year 2014
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	196,444	189,874	178,058	158,388	146,917	109,048	74,479	48,791	13,062	2,019
Reinsurance | Professional lines | Accident Year 2015
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	184,073	170,555	152,328	131,543	111,743	79,208	41,512	13,504	3,134
Reinsurance | Professional lines | Accident Year 2016
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	202,925	181,141	153,575	124,881	95,084	52,540	20,487	1,765
Reinsurance | Professional lines | Accident Year 2017
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	137,492	116,293	88,791	62,723	39,857	14,871	2,813
Reinsurance | Professional lines | Accident Year 2018
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	113,771	81,729	56,882	31,198	2,572	271
Reinsurance | Professional lines | Accident Year 2019
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	76,094	53,221	33,628	13,614	368
Reinsurance | Professional lines | Accident Year 2020
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	40,718	26,926	13,969	3,823
Reinsurance | Professional lines | Accident Year 2021
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	22,619	11,366	4,337
Reinsurance | Professional lines | Accident Year 2022
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	11,713	3,234
Reinsurance | Professional lines | Accident Year 2023
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	3,435
Reinsurance | Liability
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	1,416,642
All outstanding liabilities before 2014, net of reinsurance	130,039
Liabilities for claims and claim adjustment expenses, net of reinsurance	1,738,680
Reinsurance | Liability | Accident Year 2014
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	156,421	148,342	137,103	129,802	109,859	89,328	70,069	48,397	28,652	7,075
Reinsurance | Liability | Accident Year 2015
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	166,842	151,919	141,519	130,767	108,857	80,822	54,486	27,451	7,269
Reinsurance | Liability | Accident Year 2016
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	216,534	189,536	166,645	142,837	111,698	69,445	37,666	11,868
Reinsurance | Liability | Accident Year 2017
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	224,655	193,274	158,653	120,747	78,574	42,144	12,449
Reinsurance | Liability | Accident Year 2018
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	207,016	166,378	127,946	85,207	49,938	19,357
Reinsurance | Liability | Accident Year 2019
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	159,068	120,266	79,728	45,269	19,311
Reinsurance | Liability | Accident Year 2020
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	119,678	82,389	49,059	16,940
Reinsurance | Liability | Accident Year 2021
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	99,228	58,540	10,931
Reinsurance | Liability | Accident Year 2022
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	52,197	18,066
Reinsurance | Liability | Accident Year 2023
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	15,003
Reinsurance | Credit and surety
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	641,282
All outstanding liabilities before 2014, net of reinsurance	26,307
Liabilities for claims and claim adjustment expenses, net of reinsurance	278,501
Reinsurance | Credit and surety | Accident Year 2014
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	98,533	107,713	106,519	106,708	106,267	101,859	94,274	85,266	60,597	35,450
Reinsurance | Credit and surety | Accident Year 2015
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	118,116	120,617	121,975	121,115	117,462	115,549	98,709	81,001	32,863
Reinsurance | Credit and surety | Accident Year 2016
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	102,558	100,426	100,682	102,149	101,065	91,490	72,691	41,937
Reinsurance | Credit and surety | Accident Year 2017
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	103,252	102,390	99,463	101,337	89,715	73,362	37,246
Reinsurance | Credit and surety | Accident Year 2018
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	87,073	85,505	83,736	72,096	67,839	38,868
Reinsurance | Credit and surety | Accident Year 2019
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	49,050	46,835	44,702	30,985	19,301
Reinsurance | Credit and surety | Accident Year 2020
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	43,888	39,495	34,050	25,339
Reinsurance | Credit and surety | Accident Year 2021
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	17,175	9,170	4,471
Reinsurance | Credit and surety | Accident Year 2022
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	11,302	6,883
Reinsurance | Credit and surety | Accident Year 2023
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	10,335
Reinsurance | Motor
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	1,582,237
All outstanding liabilities before 2014, net of reinsurance	255,320
Liabilities for claims and claim adjustment expenses, net of reinsurance	1,020,952
Reinsurance | Motor | Accident Year 2014
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	141,456	138,281	135,455	114,654	119,355	109,989	100,071	92,183	73,129	43,148
Reinsurance | Motor | Accident Year 2015
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	175,479	173,373	168,295	145,593	144,878	129,175	112,128	92,382	57,638
Reinsurance | Motor | Accident Year 2016
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	198,144	189,563	182,077	158,004	145,160	127,404	103,868	60,689
Reinsurance | Motor | Accident Year 2017
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	262,741	244,440	221,060	198,778	163,724	133,447	72,143
Reinsurance | Motor | Accident Year 2018
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	260,818	240,535	215,988	205,874	141,391	83,831
Reinsurance | Motor | Accident Year 2019
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	242,207	223,167	201,210	183,841	90,328
Reinsurance | Motor | Accident Year 2020
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	127,881	115,689	96,208	43,752
Reinsurance | Motor | Accident Year 2021
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	94,500	76,338	41,869
Reinsurance | Motor | Accident Year 2022
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	52,971	35,213
Reinsurance | Motor | Accident Year 2023
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	26,040
Reinsurance | Agriculture
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	998,232
All outstanding liabilities before 2014, net of reinsurance	(463)
Liabilities for claims and claim adjustment expenses, net of reinsurance	147,622
Reinsurance | Agriculture | Accident Year 2014
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	162,194	162,068	161,167	160,516	162,011	161,498	161,575	162,349	133,137	15,615
Reinsurance | Agriculture | Accident Year 2015
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	96,224	95,612	95,457	95,468	94,873	94,535	92,979	65,870	1,716
Reinsurance | Agriculture | Accident Year 2016
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	109,762	109,211	109,172	109,410	109,922	108,378	62,530	9,489
Reinsurance | Agriculture | Accident Year 2017
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	136,605	137,429	137,482	138,640	137,502	124,528	7,444
Reinsurance | Agriculture | Accident Year 2018
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	144,070	138,398	141,768	135,674	127,577	5,115
Reinsurance | Agriculture | Accident Year 2019
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	177,760	178,264	174,250	154,533	28,854
Reinsurance | Agriculture | Accident Year 2020
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	55,359	54,269	47,377	17,454
Reinsurance | Agriculture | Accident Year 2021
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	46,117	32,846	2,953
Reinsurance | Agriculture | Accident Year 2022
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	55,508	15,347
Reinsurance | Agriculture | Accident Year 2023
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	14,633
Reinsurance | Run-off lines
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	3,069,216
All outstanding liabilities before 2014, net of reinsurance	37,075
Liabilities for claims and claim adjustment expenses, net of reinsurance	697,802
Reinsurance | Run-off lines | Accident Year 2014
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	213,063	211,708	210,435	203,726	206,234	202,114	197,284	180,580	136,404	$ 49,217
Reinsurance | Run-off lines | Accident Year 2015
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	235,258	234,318	232,671	218,469	213,978	203,661	178,596	119,103	$ 46,199
Reinsurance | Run-off lines | Accident Year 2016
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	257,802	258,939	253,543	246,602	232,366	201,290	141,975	$ 65,343
Reinsurance | Run-off lines | Accident Year 2017
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	657,803	646,826	611,106	586,833	528,640	417,693	$ 163,254
Reinsurance | Run-off lines | Accident Year 2018
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	548,005	526,746	479,911	427,126	331,848	$ 116,816
Reinsurance | Run-off lines | Accident Year 2019
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	335,546	310,612	274,503	214,066	$ 54,985
Reinsurance | Run-off lines | Accident Year 2020
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	392,613	324,105	240,193	$ 105,245
Reinsurance | Run-off lines | Accident Year 2021
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	302,383	235,617	$ 87,860
Reinsurance | Run-off lines | Accident Year 2022
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	103,881	$ 50,250
Reinsurance | Run-off lines | Accident Year 2023
Claims Development [Line Items]
Cumulative paid claims and allocated claim adjustment expenses	$ 22,862

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