RESERVE FOR LOSSES AND LOSS EXPENSES - Summary of Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance (Details) $ in Thousands	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 ($)	Dec. 31, 2013 USD ($)
Insurance | Property
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 3,940,350
Insurance | Property | Accident Year 2013
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	239,662	$ 239,749	$ 239,742	$ 240,025	$ 241,593	$ 231,357	$ 232,389	$ 236,276	$ 263,335	$ 269,749
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 608
Cumulative number of reported claims | claim	3,455
Insurance | Property | Accident Year 2014
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 252,842	252,918	255,612	259,507	261,928	262,345	276,777	287,038	288,993
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 846
Cumulative number of reported claims | claim	4,128
Insurance | Property | Accident Year 2015
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 180,614	178,338	188,334	186,403	189,724	191,987	199,738	207,460
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 322
Cumulative number of reported claims | claim	4,168
Insurance | Property | Accident Year 2016
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 258,432	259,012	258,563	264,244	278,599	286,359	263,277
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 1,763
Cumulative number of reported claims | claim	6,589
Insurance | Property | Accident Year 2017
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 674,955	674,642	679,272	688,738	696,217	790,282
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 16,736
Cumulative number of reported claims | claim	10,037
Insurance | Property | Accident Year 2018
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 619,470	620,745	628,383	648,546	601,920
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 8,696
Cumulative number of reported claims | claim	9,586
Insurance | Property | Accident Year 2019
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 356,278	344,865	354,498	365,895
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 3,174
Cumulative number of reported claims | claim	9,470
Insurance | Property | Accident Year 2020
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 574,412	625,403	639,024
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 45,011
Cumulative number of reported claims | claim	12,282
Insurance | Property | Accident Year 2021
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 371,684	375,903
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 22,282
Cumulative number of reported claims | claim	7,562
Insurance | Property | Accident Year 2022
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 412,001
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 168,886
Cumulative number of reported claims | claim	5,412
Insurance | Accident and health
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 777,271
Insurance | Accident and health | Accident Year 2013
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	35,353	33,916	32,794	33,026	35,245	35,045	34,383	34,413	34,160	38,763
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 1,220
Cumulative number of reported claims | claim	49,549
Insurance | Accident and health | Accident Year 2014
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 61,479	62,846	63,645	64,420	63,685	64,057	65,588	66,137	70,803
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 656
Cumulative number of reported claims | claim	58,081
Insurance | Accident and health | Accident Year 2015
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 62,958	62,298	62,966	63,278	62,720	64,511	67,991	69,643
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 1,495
Cumulative number of reported claims | claim	44,138
Insurance | Accident and health | Accident Year 2016
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 85,738	85,938	84,921	85,247	84,118	83,697	84,024
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 1,597
Cumulative number of reported claims | claim	87,001
Insurance | Accident and health | Accident Year 2017
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 114,738	114,855	114,782	116,690	118,736	112,583
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 160
Cumulative number of reported claims | claim	688,000
Insurance | Accident and health | Accident Year 2018
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 111,865	110,861	112,819	113,711	109,900
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 170
Cumulative number of reported claims | claim	738,139
Insurance | Accident and health | Accident Year 2019
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 68,074	64,586	74,084	72,971
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ (482)
Cumulative number of reported claims | claim	668,008
Insurance | Accident and health | Accident Year 2020
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 66,975	63,476	69,316
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 1,475
Cumulative number of reported claims | claim	713,198
Insurance | Accident and health | Accident Year 2021
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 71,672	69,349
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 1,695
Cumulative number of reported claims | claim	418,260
Insurance | Accident and health | Accident Year 2022
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 98,419
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 46,362
Cumulative number of reported claims | claim	227,274
Insurance | Marine and aviation
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 1,717,347
Insurance | Marine and aviation | Accident Year 2013
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	94,037	95,315	94,661	95,565	95,389	95,998	110,382	109,330	115,403	94,098
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 618
Cumulative number of reported claims | claim	3,401
Insurance | Marine and aviation | Accident Year 2014
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 52,696	53,409	56,132	64,264	66,228	64,952	71,356	66,912	79,979
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 922
Cumulative number of reported claims | claim	3,550
Insurance | Marine and aviation | Accident Year 2015
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 146,338	146,411	146,923	141,433	154,835	162,516	166,614	187,548
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 1,083
Cumulative number of reported claims | claim	4,292
Insurance | Marine and aviation | Accident Year 2016
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 101,331	100,428	101,293	101,880	109,445	111,852	115,466
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 1,236
Cumulative number of reported claims | claim	4,821
Insurance | Marine and aviation | Accident Year 2017
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 219,134	219,372	227,315	229,379	228,267	260,951
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 13,765
Cumulative number of reported claims | claim	8,537
Insurance | Marine and aviation | Accident Year 2018
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 234,514	241,156	247,886	261,748	236,572
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 22,650
Cumulative number of reported claims | claim	8,699
Insurance | Marine and aviation | Accident Year 2019
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 221,420	208,657	205,829	211,337
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 9,334
Cumulative number of reported claims | claim	7,566
Insurance | Marine and aviation | Accident Year 2020
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 161,972	178,479	206,992
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 24,006
Cumulative number of reported claims | claim	6,741
Insurance | Marine and aviation | Accident Year 2021
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 221,510	240,192
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 68,116
Cumulative number of reported claims | claim	6,354
Insurance | Marine and aviation | Accident Year 2022
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 264,395
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 179,643
Cumulative number of reported claims | claim	5,240
Insurance | Cyber
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 675,374
Insurance | Cyber | Accident Year 2013
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	35,564	32,557	32,591	33,537	34,399	42,557	47,310	65,870	66,409	67,211
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 5,447
Cumulative number of reported claims | claim	1,335
Insurance | Cyber | Accident Year 2014
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 39,832	43,576	39,516	42,887	47,342	57,876	69,955	69,690	70,557
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 1,733
Cumulative number of reported claims | claim	1,114
Insurance | Cyber | Accident Year 2015
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 49,795	52,526	50,758	50,357	51,250	63,066	63,595	65,231
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 5,857
Cumulative number of reported claims | claim	1,337
Insurance | Cyber | Accident Year 2016
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 27,873	29,929	37,322	40,266	58,261	56,565	58,741
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 4,478
Cumulative number of reported claims | claim	1,532
Insurance | Cyber | Accident Year 2017
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 49,327	51,050	52,058	56,910	50,794	53,187
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 6,722
Cumulative number of reported claims | claim	1,623
Insurance | Cyber | Accident Year 2018
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 27,332	31,009	34,151	32,155	33,429
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 5,745
Cumulative number of reported claims | claim	1,966
Insurance | Cyber | Accident Year 2019
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 81,402	81,757	58,702	54,671
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 16,951
Cumulative number of reported claims | claim	2,796
Insurance | Cyber | Accident Year 2020
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 102,606	105,868	113,744
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 22,194
Cumulative number of reported claims | claim	2,821
Insurance | Cyber | Accident Year 2021
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 133,673	124,596
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 50,583
Cumulative number of reported claims | claim	2,356
Insurance | Cyber | Accident Year 2022
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 127,970
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 110,682
Cumulative number of reported claims | claim	1,341
Insurance | Professional lines
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 3,575,139
Insurance | Professional lines | Accident Year 2013
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	290,531	295,366	298,702	294,284	315,038	305,212	311,998	326,531	327,011	314,230
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 23,664
Cumulative number of reported claims | claim	8,148
Insurance | Professional lines | Accident Year 2014
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 299,310	301,754	302,187	304,932	317,641	327,693	344,642	335,403	335,549
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 39,805
Cumulative number of reported claims | claim	8,759
Insurance | Professional lines | Accident Year 2015
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 281,916	269,672	270,904	287,955	301,324	314,890	307,995	307,130
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 24,939
Cumulative number of reported claims | claim	9,211
Insurance | Professional lines | Accident Year 2016
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 338,634	335,757	325,816	313,363	295,253	291,012	286,248
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 32,529
Cumulative number of reported claims | claim	10,424
Insurance | Professional lines | Accident Year 2017
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 389,053	388,973	371,589	371,629	338,031	335,706
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 72,532
Cumulative number of reported claims | claim	12,380
Insurance | Professional lines | Accident Year 2018
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 445,652	417,600	387,583	338,625	322,911
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 93,119
Cumulative number of reported claims | claim	14,996
Insurance | Professional lines | Accident Year 2019
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 408,585	373,074	358,459	342,656
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 121,148
Cumulative number of reported claims | claim	14,335
Insurance | Professional lines | Accident Year 2020
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 299,008	317,999	319,015
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 166,308
Cumulative number of reported claims | claim	9,128
Insurance | Professional lines | Accident Year 2021
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 366,258	374,828
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 305,139
Cumulative number of reported claims | claim	7,766
Insurance | Professional lines | Accident Year 2022
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 456,192
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 436,877
Cumulative number of reported claims | claim	6,263
Insurance | Credit and political risk
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 377,579
Insurance | Credit and political risk | Accident Year 2013
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	12,151	12,614	12,739	12,377	14,067	14,942	9,880	9,759	25,684	26,439
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 0
Cumulative number of reported claims | claim	2
Insurance | Credit and political risk | Accident Year 2014
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 69,677	69,112	70,748	71,274	69,589	68,323	67,109	70,712	38,825
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 0
Cumulative number of reported claims | claim	6
Insurance | Credit and political risk | Accident Year 2015
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 23,309	24,189	24,851	25,930	26,012	27,524	30,368	30,329
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 0
Cumulative number of reported claims | claim	2
Insurance | Credit and political risk | Accident Year 2016
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 25,291	26,371	27,352	43,566	42,995	45,485	44,175
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 0
Cumulative number of reported claims | claim	1
Insurance | Credit and political risk | Accident Year 2017
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 11,993	16,952	19,234	27,007	32,612	47,934
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 4,283
Cumulative number of reported claims | claim	3
Insurance | Credit and political risk | Accident Year 2018
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 22,577	26,231	34,240	35,296	42,588
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 9,191
Cumulative number of reported claims | claim	2
Insurance | Credit and political risk | Accident Year 2019
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 70,888	72,450	77,987	50,079
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 7,985
Cumulative number of reported claims | claim	20
Insurance | Credit and political risk | Accident Year 2020
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 59,519	68,347	59,758
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 25,535
Cumulative number of reported claims | claim	39
Insurance | Credit and political risk | Accident Year 2021
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 36,943	42,229
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 30,912
Cumulative number of reported claims | claim	17
Insurance | Credit and political risk | Accident Year 2022
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 45,231
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 40,828
Cumulative number of reported claims | claim	13
Insurance | Liability
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 2,009,958
Insurance | Liability | Accident Year 2013
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	97,047	94,196	89,897	91,938	95,978	93,677	88,237	95,170	95,304	93,230
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 12,187
Cumulative number of reported claims | claim	3,737
Insurance | Liability | Accident Year 2014
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 132,659	132,029	132,551	131,461	132,006	130,659	129,725	124,264	107,115
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 12,691
Cumulative number of reported claims | claim	5,531
Insurance | Liability | Accident Year 2015
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 188,577	186,853	187,927	182,612	164,915	137,385	127,236	128,435
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 22,972
Cumulative number of reported claims | claim	6,574
Insurance | Liability | Accident Year 2016
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 125,644	120,101	120,116	127,366	128,782	130,127	124,307
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 21,537
Cumulative number of reported claims | claim	7,417
Insurance | Liability | Accident Year 2017
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 215,101	204,612	200,470	184,847	165,415	166,717
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 21,746
Cumulative number of reported claims | claim	8,629
Insurance | Liability | Accident Year 2018
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 216,530	204,879	190,809	167,808	166,973
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 29,705
Cumulative number of reported claims | claim	8,473
Insurance | Liability | Accident Year 2019
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 236,959	221,266	191,683	190,645
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 43,102
Cumulative number of reported claims | claim	7,936
Insurance | Liability | Accident Year 2020
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 230,421	223,996	223,579
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 113,650
Cumulative number of reported claims | claim	5,848
Insurance | Liability | Accident Year 2021
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 244,972	231,189
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 150,924
Cumulative number of reported claims | claim	5,965
Insurance | Liability | Accident Year 2022
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 322,048
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 282,198
Cumulative number of reported claims | claim	4,657
Reinsurance | Accident and health
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	$ 1,777,335
Reinsurance | Accident and health | Accident Year 2013
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	111,294	111,277	111,198	111,162	111,162	111,155	111,623	113,009	113,631	108,977
Total of incurred-but-not-reported liabilities plus expected development on reported claims	757
Reinsurance | Accident and health | Accident Year 2014
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	87,906	88,021	87,734	86,774	86,772	86,765	89,238	102,354	101,383
Total of incurred-but-not-reported liabilities plus expected development on reported claims	1,106
Reinsurance | Accident and health | Accident Year 2015
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	92,313	92,350	93,341	93,007	93,722	93,964	100,434	93,792
Total of incurred-but-not-reported liabilities plus expected development on reported claims	(1,876)
Reinsurance | Accident and health | Accident Year 2016
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	190,356	190,426	189,403	189,929	188,320	191,188	170,644
Total of incurred-but-not-reported liabilities plus expected development on reported claims	(613)
Reinsurance | Accident and health | Accident Year 2017
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	183,077	183,120	182,097	183,286	189,430	183,817
Total of incurred-but-not-reported liabilities plus expected development on reported claims	1,528
Reinsurance | Accident and health | Accident Year 2018
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	200,190	200,854	198,105	200,269	193,667
Total of incurred-but-not-reported liabilities plus expected development on reported claims	4,693
Reinsurance | Accident and health | Accident Year 2019
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	204,951	207,347	211,896	217,320
Total of incurred-but-not-reported liabilities plus expected development on reported claims	5,896
Reinsurance | Accident and health | Accident Year 2020
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	213,230	220,334	226,549
Total of incurred-but-not-reported liabilities plus expected development on reported claims	(7,052)
Reinsurance | Accident and health | Accident Year 2021
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	226,659	231,754
Total of incurred-but-not-reported liabilities plus expected development on reported claims	26,816
Reinsurance | Accident and health | Accident Year 2022
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	267,359
Total of incurred-but-not-reported liabilities plus expected development on reported claims	146,819
Reinsurance | Marine and aviation
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	381,834
Reinsurance | Marine and aviation | Accident Year 2013
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	6,599	6,575	6,558	6,226	6,523	6,560	6,487	6,676	12,441	11,961
Total of incurred-but-not-reported liabilities plus expected development on reported claims	(565)
Reinsurance | Marine and aviation | Accident Year 2014
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	9,505	9,003	8,764	8,514	9,166	7,182	7,990	9,142	10,183
Total of incurred-but-not-reported liabilities plus expected development on reported claims	423
Reinsurance | Marine and aviation | Accident Year 2015
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	11,968	12,016	12,251	12,620	14,979	10,806	9,217	10,363
Total of incurred-but-not-reported liabilities plus expected development on reported claims	418
Reinsurance | Marine and aviation | Accident Year 2016
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	36,238	35,834	35,511	36,996	35,605	35,330	32,280
Total of incurred-but-not-reported liabilities plus expected development on reported claims	625
Reinsurance | Marine and aviation | Accident Year 2017
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	40,887	43,230	46,608	41,360	42,760	55,072
Total of incurred-but-not-reported liabilities plus expected development on reported claims	844
Reinsurance | Marine and aviation | Accident Year 2018
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	47,522	44,042	27,609	28,072	18,830
Total of incurred-but-not-reported liabilities plus expected development on reported claims	443
Reinsurance | Marine and aviation | Accident Year 2019
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	80,976	79,146	81,480	69,056
Total of incurred-but-not-reported liabilities plus expected development on reported claims	5,760
Reinsurance | Marine and aviation | Accident Year 2020
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	38,273	42,071	40,548
Total of incurred-but-not-reported liabilities plus expected development on reported claims	4,380
Reinsurance | Marine and aviation | Accident Year 2021
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	40,968	43,886
Total of incurred-but-not-reported liabilities plus expected development on reported claims	15,886
Reinsurance | Marine and aviation | Accident Year 2022
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	68,898
Total of incurred-but-not-reported liabilities plus expected development on reported claims	54,268
Reinsurance | Professional lines
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	1,876,315
Reinsurance | Professional lines | Accident Year 2013
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	168,014	164,383	168,466	180,269	204,246	212,039	212,750	214,632	213,826	208,838
Total of incurred-but-not-reported liabilities plus expected development on reported claims	5,422
Reinsurance | Professional lines | Accident Year 2014
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	233,317	225,276	227,327	228,865	232,493	218,251	218,600	218,664	218,770
Total of incurred-but-not-reported liabilities plus expected development on reported claims	5,973
Reinsurance | Professional lines | Accident Year 2015
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	240,255	234,298	227,545	230,650	224,028	213,463	211,312	211,463
Total of incurred-but-not-reported liabilities plus expected development on reported claims	12,860
Reinsurance | Professional lines | Accident Year 2016
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	266,249	254,339	254,459	226,932	199,369	195,775	194,725
Total of incurred-but-not-reported liabilities plus expected development on reported claims	28,900
Reinsurance | Professional lines | Accident Year 2017
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	209,111	186,713	176,930	161,029	154,910	154,457
Total of incurred-but-not-reported liabilities plus expected development on reported claims	31,256
Reinsurance | Professional lines | Accident Year 2018
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	172,749	164,966	154,366	147,533	145,212
Total of incurred-but-not-reported liabilities plus expected development on reported claims	37,223
Reinsurance | Professional lines | Accident Year 2019
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	144,336	140,144	136,277	136,846
Total of incurred-but-not-reported liabilities plus expected development on reported claims	48,864
Reinsurance | Professional lines | Accident Year 2020
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	134,318	140,003	139,748
Total of incurred-but-not-reported liabilities plus expected development on reported claims	82,908
Reinsurance | Professional lines | Accident Year 2021
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	139,493	147,961
Total of incurred-but-not-reported liabilities plus expected development on reported claims	112,421
Reinsurance | Professional lines | Accident Year 2022
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	168,473
Total of incurred-but-not-reported liabilities plus expected development on reported claims	154,252
Reinsurance | Liability
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	2,641,014
Reinsurance | Liability | Accident Year 2013
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	157,106	154,142	155,720	156,816	176,171	182,782	183,051	181,007	175,116	171,362
Total of incurred-but-not-reported liabilities plus expected development on reported claims	9,769
Reinsurance | Liability | Accident Year 2014
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	188,328	182,375	186,489	195,959	198,098	199,379	203,470	201,764	198,852
Total of incurred-but-not-reported liabilities plus expected development on reported claims	16,201
Reinsurance | Liability | Accident Year 2015
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	205,594	202,698	212,908	212,574	214,736	214,899	213,954	213,612
Total of incurred-but-not-reported liabilities plus expected development on reported claims	19,016
Reinsurance | Liability | Accident Year 2016
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	273,312	265,953	262,011	252,359	249,096	244,275	239,071
Total of incurred-but-not-reported liabilities plus expected development on reported claims	33,727
Reinsurance | Liability | Accident Year 2017
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	305,418	296,174	286,761	278,111	268,712	273,964
Total of incurred-but-not-reported liabilities plus expected development on reported claims	46,899
Reinsurance | Liability | Accident Year 2018
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	305,168	285,643	272,753	267,501	262,831
Total of incurred-but-not-reported liabilities plus expected development on reported claims	61,173
Reinsurance | Liability | Accident Year 2019
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	271,247	273,061	271,050	262,191
Total of incurred-but-not-reported liabilities plus expected development on reported claims	88,379
Reinsurance | Liability | Accident Year 2020
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	277,697	283,457	282,871
Total of incurred-but-not-reported liabilities plus expected development on reported claims	146,037
Reinsurance | Liability | Accident Year 2021
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	310,759	303,482
Total of incurred-but-not-reported liabilities plus expected development on reported claims	196,806
Reinsurance | Liability | Accident Year 2022
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	346,385
Total of incurred-but-not-reported liabilities plus expected development on reported claims	298,804
Reinsurance | Credit and surety
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	938,595
Reinsurance | Credit and surety | Accident Year 2013
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	124,760	123,641	124,850	122,035	121,824	132,814	136,726	140,520	149,561	162,254
Total of incurred-but-not-reported liabilities plus expected development on reported claims	1,647
Reinsurance | Credit and surety | Accident Year 2014
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	119,216	118,853	120,171	123,854	125,086	136,104	139,686	132,589	132,954
Total of incurred-but-not-reported liabilities plus expected development on reported claims	133
Reinsurance | Credit and surety | Accident Year 2015
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	131,093	136,667	135,496	134,568	152,946	156,701	161,881	157,589
Total of incurred-but-not-reported liabilities plus expected development on reported claims	1,530
Reinsurance | Credit and surety | Accident Year 2016
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	108,856	111,192	113,526	120,945	146,132	138,424	139,437
Total of incurred-but-not-reported liabilities plus expected development on reported claims	1,206
Reinsurance | Credit and surety | Accident Year 2017
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	112,383	112,679	115,202	123,877	129,727	136,280
Total of incurred-but-not-reported liabilities plus expected development on reported claims	2,461
Reinsurance | Credit and surety | Accident Year 2018
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	103,324	108,388	111,340	117,215	109,771
Total of incurred-but-not-reported liabilities plus expected development on reported claims	9,933
Reinsurance | Credit and surety | Accident Year 2019
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	63,943	66,175	66,316	73,090
Total of incurred-but-not-reported liabilities plus expected development on reported claims	9,256
Reinsurance | Credit and surety | Accident Year 2020
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	68,410	83,053	76,516
Total of incurred-but-not-reported liabilities plus expected development on reported claims	16,290
Reinsurance | Credit and surety | Accident Year 2021
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	43,485	51,721
Total of incurred-but-not-reported liabilities plus expected development on reported claims	21,500
Reinsurance | Credit and surety | Accident Year 2022
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	63,125
Total of incurred-but-not-reported liabilities plus expected development on reported claims	50,105
Reinsurance | Motor
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	2,207,122
Reinsurance | Motor | Accident Year 2013
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	107,772	107,275	111,011	113,999	122,196	125,052	128,421	137,357	148,570	154,629
Total of incurred-but-not-reported liabilities plus expected development on reported claims	5,350
Reinsurance | Motor | Accident Year 2014
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	152,730	152,080	152,566	155,735	159,020	163,297	166,277	171,207	174,534
Total of incurred-but-not-reported liabilities plus expected development on reported claims	2,906
Reinsurance | Motor | Accident Year 2015
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	196,266	196,003	198,653	199,861	210,117	208,365	204,962	214,064
Total of incurred-but-not-reported liabilities plus expected development on reported claims	6,881
Reinsurance | Motor | Accident Year 2016
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	231,759	228,144	230,691	238,949	248,315	246,951	236,330
Total of incurred-but-not-reported liabilities plus expected development on reported claims	3,531
Reinsurance | Motor | Accident Year 2017
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	337,372	342,097	341,108	340,571	350,773	347,985
Total of incurred-but-not-reported liabilities plus expected development on reported claims	12,195
Reinsurance | Motor | Accident Year 2018
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	330,259	342,114	345,746	335,555	343,073
Total of incurred-but-not-reported liabilities plus expected development on reported claims	12,092
Reinsurance | Motor | Accident Year 2019
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	317,512	325,792	325,918	328,062
Total of incurred-but-not-reported liabilities plus expected development on reported claims	23,908
Reinsurance | Motor | Accident Year 2020
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	205,512	207,767	205,885
Total of incurred-but-not-reported liabilities plus expected development on reported claims	38,657
Reinsurance | Motor | Accident Year 2021
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	173,409	173,077
Total of incurred-but-not-reported liabilities plus expected development on reported claims	36,756
Reinsurance | Motor | Accident Year 2022
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	154,531
Total of incurred-but-not-reported liabilities plus expected development on reported claims	69,678
Reinsurance | Agriculture
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	1,175,230
Reinsurance | Agriculture | Accident Year 2013
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	121,752	120,853	121,805	120,919	120,799	120,807	120,795	121,107	117,467	107,068
Total of incurred-but-not-reported liabilities plus expected development on reported claims	(330)
Reinsurance | Agriculture | Accident Year 2014
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	162,756	162,061	162,239	162,321	162,308	162,382	162,814	164,334	183,242
Total of incurred-but-not-reported liabilities plus expected development on reported claims	437
Reinsurance | Agriculture | Accident Year 2015
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	95,621	95,490	95,504	95,326	95,320	95,334	95,592	103,172
Total of incurred-but-not-reported liabilities plus expected development on reported claims	(33)
Reinsurance | Agriculture | Accident Year 2016
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	108,599	108,647	109,457	109,218	110,630	117,507	123,798
Total of incurred-but-not-reported liabilities plus expected development on reported claims	(227)
Reinsurance | Agriculture | Accident Year 2017
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	137,431	138,898	139,427	138,357	144,281	151,649
Total of incurred-but-not-reported liabilities plus expected development on reported claims	(238)
Reinsurance | Agriculture | Accident Year 2018
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	139,907	140,538	140,806	147,271	140,936
Total of incurred-but-not-reported liabilities plus expected development on reported claims	1,412
Reinsurance | Agriculture | Accident Year 2019
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	183,289	187,685	185,218	184,177
Total of incurred-but-not-reported liabilities plus expected development on reported claims	1,679
Reinsurance | Agriculture | Accident Year 2020
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	63,778	62,738	62,593
Total of incurred-but-not-reported liabilities plus expected development on reported claims	3,775
Reinsurance | Agriculture | Accident Year 2021
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	61,225	69,759
Total of incurred-but-not-reported liabilities plus expected development on reported claims	9,475
Reinsurance | Agriculture | Accident Year 2022
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	100,872
Total of incurred-but-not-reported liabilities plus expected development on reported claims	77,550
Reinsurance | Run Off Lines
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	3,972,281
Reinsurance | Run Off Lines | Accident Year 2013
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	251,472	252,736	254,589	256,433	259,488	260,012	265,575	282,546	308,714	$ 339,293
Total of incurred-but-not-reported liabilities plus expected development on reported claims	927
Reinsurance | Run Off Lines | Accident Year 2014
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	217,746	218,620	218,807	222,835	223,003	226,620	235,489	245,246	$ 241,052
Total of incurred-but-not-reported liabilities plus expected development on reported claims	1,354
Reinsurance | Run Off Lines | Accident Year 2015
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	244,839	246,716	248,890	243,963	245,175	254,344	254,255	$ 265,915
Total of incurred-but-not-reported liabilities plus expected development on reported claims	4,350
Reinsurance | Run Off Lines | Accident Year 2016
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	279,384	279,338	278,910	275,463	280,767	284,044	$ 284,047
Total of incurred-but-not-reported liabilities plus expected development on reported claims	5,861
Reinsurance | Run Off Lines | Accident Year 2017
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	732,026	741,329	743,340	742,280	703,287	$ 703,634
Total of incurred-but-not-reported liabilities plus expected development on reported claims	22,110
Reinsurance | Run Off Lines | Accident Year 2018
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	604,626	618,695	632,623	617,378	$ 523,856
Total of incurred-but-not-reported liabilities plus expected development on reported claims	14,356
Reinsurance | Run Off Lines | Accident Year 2019
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	401,170	419,002	439,421	$ 454,804
Total of incurred-but-not-reported liabilities plus expected development on reported claims	30,117
Reinsurance | Run Off Lines | Accident Year 2020
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	542,837	548,722	$ 517,487
Total of incurred-but-not-reported liabilities plus expected development on reported claims	60,793
Reinsurance | Run Off Lines | Accident Year 2021
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	434,809	$ 425,525
Total of incurred-but-not-reported liabilities plus expected development on reported claims	54,826
Reinsurance | Run Off Lines | Accident Year 2022
Claims Development [Line Items]
Incurred claims and allocated claim adjustment expenses	263,372
Total of incurred-but-not-reported liabilities plus expected development on reported claims	$ 139,192