Historical Loss And LAE Development (Tables)

12 Months Ended

Dec. 31, 2023

Historical Loss And L A E Development Disclosure [Abstract]

Schedule of Reconciliation of Unpaid Losses and Settlement Expenses (LAE)

The following table is a reconciliation of our unpaid losses and settlement expenses (LAE) for the years 2023, 2022 and 2021:

(in thousands)	2023		2022		2021
Unpaid losses and LAE at beginning of year:
Gross	$	2,315,637	$	2,043,555	$	1,750,049
Ceded		(740,089)		(608,086)		(443,729)
Net	$	1,575,548	$	1,435,469	$	1,306,320
Increase (decrease) in incurred losses and LAE:
Current accident year	$	712,960	$	636,955	$	582,065
Prior accident years		(108,547)		(122,579)		(125,463)
Total incurred	$	604,413	$	514,376	$	456,602
Loss and LAE payments for claims incurred:
Current accident year	$	(165,364)	$	(97,525)	$	(101,590)
Prior accident year		(325,921)		(276,772)		(225,863)
Total paid	$	(491,285)	$	(374,297)	$	(327,453)
Net unpaid losses and LAE at end of year	$	1,688,676	$	1,575,548	$	1,435,469
Unpaid losses and LAE at end of year:
Gross	$	2,446,025	$	2,315,637	$	2,043,555
Ceded		(757,349)		(740,089)		(608,086)
Net	$	1,688,676	$	1,575,548	$	1,435,469

Schedule of Incurred and Paid Claims Development

Casualty - Primary Occurrence
(in thousands, except number of claims)
	Incurred Losses and Loss Adjustment Expenses, Net of Reinsurance																				As of December 31, 2023
	For the Years Ended December 31,																						Cumulative
																							Number of
																							Reported
AY	2014*		2015*		2016*		2017*		2018*		2019*		2020*		2021*		2022*		2023		Total IBNR		Claims
2014	$	88,092	$	79,497	$	71,592	$	67,237	$	66,389	$	66,702	$	65,636	$	63,727	$	64,449	$	64,160	$	1,844	4,303
2015				94,835		84,975		83,579		78,675		76,398		75,470		75,438		77,110		75,958		3,048	4,416
2016						101,950		96,753		90,611		85,449		83,374		79,440		77,729		78,358		5,321	4,349
2017								119,741		111,391		102,583		95,513		90,759		90,344		90,744		8,014	4,550
2018										141,513		130,281		125,731		115,076		114,414		115,793		13,981	4,902
2019												146,011		135,209		120,570		109,051		111,156		24,277	5,334
2020														145,171		137,439		122,785		117,962		42,852	4,697
2021																142,797		128,483		125,672		59,412	4,581
2022																		155,203		144,861		88,355	4,557
2023																				152,443		115,076	3,770
																		Total	$	1,077,107

	Cumulative Paid Loss and Loss Adjustment Expenses, Net of Reinsurance
	For the Years Ended December 31,
AY	2014*		2015*		2016*		2017*		2018*		2019*		2020*		2021*		2022*		2023
2014	$	11,436	$	18,771	$	29,545	$	40,270	$	47,343	$	52,387	$	55,965	$	56,784	$	58,361	$	59,783
2015				10,157		19,902		33,020		45,056		54,270		58,866		62,997		68,650		69,635
2016						10,142		24,186		35,764		48,042		56,152		60,349		65,517		69,968
2017								13,154		25,933		38,783		52,823		62,236		71,419		76,283
2018										15,066		32,365		48,424		63,980		78,103		93,504
2019												15,698		30,673		41,911		57,750		74,380
2020														17,096		30,596		45,267		60,764
2021																14,428		29,633		43,951
2022																		17,714		38,712
2023																				17,707
		* Presented as unaudited required supplementary information.																Total	$	604,687
										All outstanding liabilities before 2014, net of reinsurance										10,149
								Liabilities for losses and loss adjustment expenses, net of reinsurance											$	482,569

	Average Annual Percentage Payout of Incurred Losses by Age, Net of Reinsurance*
Years	1		2		3		4		5		6		7		8		9		10
		13.6%		13.6%		13.9%		14.9%		11.8%		8.5%		5.7%		4.8%		1.9%		2.2%

Casualty - Excess Occurrence
(in thousands, except number of claims)
	Incurred Losses and Loss Adjustment Expenses, Net of Reinsurance																				As of December 31, 2023
	For the Years Ended December 31,																						Cumulative
																							Number of
																							Reported
AY	2014*		2015*		2016*		2017*		2018*		2019*		2020*		2021*		2022*		2023		Total IBNR		Claims
2014	$	50,889	$	39,095	$	35,119	$	32,274	$	33,372	$	33,458	$	35,128	$	35,683	$	35,918	$	37,804	$	1,811	932
2015				53,672		50,857		47,392		42,840		43,328		42,446		41,690		41,471		40,580		2,287	707
2016						56,341		49,385		37,676		33,125		30,251		29,671		29,940		27,733		3,281	656
2017								62,863		55,868		48,363		44,737		43,249		41,620		39,600		9,045	656
2018										69,362		62,646		54,626		51,023		49,861		47,949		17,886	622
2019												88,078		89,691		79,083		80,147		77,185		29,498	694
2020														107,579		98,409		90,274		81,284		48,145	635
2021																136,433		136,354		125,028		64,648	820
2022																		153,895		156,822		90,640	866
2023																				178,887		120,637	540
																		Total	$	812,872

	Cumulative Paid Loss and Loss Adjustment Expenses, Net of Reinsurance
	For the Years Ended December 31,
AY	2014*		2015*		2016*		2017*		2018*		2019*		2020*		2021*		2022*		2023
2014	$	1,899	$	4,006	$	11,002	$	18,852	$	22,541	$	23,376	$	26,068	$	28,963	$	30,484	$	33,423
2015				2,048		10,127		19,571		23,184		28,756		31,352		32,752		35,958		36,559
2016						1,068		3,396		7,441		10,054		12,703		14,400		17,807		20,603
2017								17		5,679		9,275		15,441		18,470		22,835		25,328
2018										2,506		5,823		10,801		17,294		22,016		23,958
2019												4,213		19,044		25,389		33,375		38,291
2020														2,901		13,856		20,988		24,657
2021																5,317		23,841		38,977
2022																		7,479		28,764
2023																				7,091
		* Presented as unaudited required supplementary information.																Total	$	277,651
										All outstanding liabilities before 2014, net of reinsurance										21,757
								Liabilities for losses and loss adjustment expenses, net of reinsurance											$	556,978

	Average Annual Percentage Payout of Incurred Losses by Age, Net of Reinsurance*
Years	1		2		3		4		5		6		7		8		9		10
		4.1%		12.9%		13.1%		11.9%		9.5%		6.0%		7.3%		8.5%		2.8%		7.8%

Casualty - Claims Made
(in thousands, except number of claims)
	Incurred Losses and Loss Adjustment Expenses, Net of Reinsurance																				As of December 31, 2023
	For the Years Ended December 31,																						Cumulative
																							Number of
																							Reported
AY	2014*		2015*		2016*		2017*		2018*		2019*		2020*		2021*		2022*		2023		Total IBNR		Claims
2014	$	53,929	$	55,386	$	58,152	$	55,350	$	51,554	$	53,841	$	53,783	$	52,619	$	52,796	$	52,557	$	1,335	1,306
2015				55,006		47,831		42,206		39,906		39,653		39,619		38,609		37,578		37,332		935	1,338
2016						59,992		67,760		69,493		67,728		64,730		65,078		61,876		61,881		1,452	1,507
2017								60,572		62,450		62,714		57,450		59,907		61,546		60,340		3,053	1,648
2018										66,128		62,416		56,468		48,457		47,692		43,912		4,611	1,394
2019												62,918		61,712		52,224		46,500		43,969		10,846	1,513
2020														60,278		56,785		46,853		40,878		18,725	1,297
2021																51,219		45,854		38,946		22,443	1,224
2022																		58,289		55,316		34,438	1,139
2023																				54,679		40,398	1,077
																		Total	$	489,810

	Cumulative Paid Loss and Loss Adjustment Expenses, Net of Reinsurance
	For the Years Ended December 31,
AY	2014*		2015*		2016*		2017*		2018*		2019*		2020*		2021*		2022*			2023
2014	$	1,705	$	9,775	$	27,923	$	35,755	$	40,080	$	44,127	$	46,122	$	50,714	$	51,063	$		51,078
2015				2,215		10,738		16,774		20,920		28,795		32,241		33,529		34,671			35,408
2016						2,060		14,558		27,465		39,370		47,999		52,846		53,737			56,342
2017								2,455		11,350		22,728		36,522		42,918		47,087			50,623
2018										1,964		11,965		18,840		24,918		27,351			31,002
2019												1,839		8,123		14,117		19,930			27,133
2020														1,488		5,687		10,412			16,537
2021																999		5,615			8,661
2022																		2,088			8,836
2023																					1,421
		* Presented as unaudited required supplementary information.																Total		$	287,041
										All outstanding liabilities before 2014, net of reinsurance											4,795
								Liabilities for losses and loss adjustment expenses, net of reinsurance												$	207,564

	Average Annual Percentage Payout of Incurred Losses by Age, Net of Reinsurance*
Years	1		2		3		4		5		6		7		8		9		10
		3.8%		16.1%		17.4%		15.7%		12.6%		8.0%		3.6%		5.3%		1.3%		0.0%

Casualty - Transportation
(in thousands, except number of claims)
	Incurred Losses and Loss Adjustment Expenses, Net of Reinsurance																				As of December 31, 2023
	For the Years Ended December 31,																						Cumulative
																							Number of
																							Reported
AY	2014*		2015*		2016*		2017*		2018*		2019*		2020*		2021*		2022*		2023		Total IBNR		Claims
2014	$	38,361	$	33,015	$	36,452	$	38,590	$	40,202	$	40,508	$	41,156	$	41,974	$	42,067	$	41,940	$	274	3,099
2015				38,561		46,258		47,021		46,395		45,162		45,525		45,807		46,685		47,466		570	3,188
2016						50,430		53,519		54,105		52,277		52,818		53,915		55,718		56,515		959	3,944
2017								55,640		53,641		45,017		43,764		45,351		46,742		47,619		1,075	3,640
2018										57,597		54,592		38,719		36,468		35,442		35,776		1,538	3,405
2019												58,297		56,129		43,976		41,925		44,236		2,996	3,318
2020														43,573		35,524		27,665		28,856		4,251	1,647
2021																51,322		51,581		47,913		6,990	2,318
2022																		60,862		53,680		14,840	2,708
2023																				66,863		16,584	2,488
																		Total	$	470,864

		Cumulative Paid Loss and Loss Adjustment Expenses, Net of Reinsurance
		For the Years Ended December 31,
AY	2014*		2015*		2016*		2017*		2018*		2019*		2020*		2021*		2022*		2023
2014	$	7,125	$	13,933	$	19,676	$	27,457	$	33,190	$	38,282	$	40,006	$	40,427	$	41,528	$	41,564
2015				6,984		20,709		29,554		37,222		39,339		41,345		42,626		45,002		46,159
2016						8,923		18,354		30,354		38,001		43,564		47,488		52,555		54,245
2017								7,979		17,070		24,090		30,260		36,141		41,064		43,891
2018										6,980		12,827		19,216		24,503		28,844		30,916
2019												7,148		15,852		21,120		26,422		35,546
2020														3,986		7,876		12,035		20,749
2021																5,341		15,345		25,886
2022																		6,442		18,296
2023																				7,407
		* Presented as unaudited required supplementary information.																Total	$	324,659
										All outstanding liabilities before 2014, net of reinsurance										2,021
								Liabilities for losses and loss adjustment expenses, net of reinsurance											$	148,226

	Average Annual Percentage Payout of Incurred Losses by Age, Net of Reinsurance*
Years	1		2		3		4		5		6		7		8		9		10
		14.8%		19.3%		16.8%		16.9%		12.2%		7.9%		5.4%		3.0%		2.5%		0.1%

Property
(in thousands, except number of claims)
	Incurred Losses and Loss Adjustment Expenses, Net of Reinsurance																				As of December 31, 2023
	For the Years Ended December 31,																						Cumulative
																							Number of
																							Reported
AY	2014*		2015*		2016*		2017*		2018*		2019*		2020*		2021*		2022*		2023		Total IBNR		Claims
2014	$	56,587	$	49,441	$	48,801	$	48,761	$	49,217	$	49,444	$	49,479	$	49,520	$	49,468	$	49,413	$	2	4,564
2015				59,863		56,103		53,958		52,720		53,111		52,781		52,878		53,359		54,065		6	4,077
2016						62,900		55,594		55,384		55,930		55,424		55,383		55,536		55,385		34	3,379
2017								90,803		83,273		84,961		82,671		82,319		81,912		81,677		517	2,893
2018										89,091		83,457		79,961		80,470		79,093		79,234		1,177	2,339
2019												71,232		65,189		61,116		59,901		61,185		975	2,458
2020														118,247		110,466		108,546		108,363		6,190	2,861
2021																135,447		116,424		115,587		7,512	3,103
2022																		138,756		119,877		18,613	2,940
2023																				184,252		51,040	2,881
																		Total	$	909,038

	Cumulative Paid Loss and Loss Adjustment Expenses, Net of Reinsurance
	For the Years Ended December 31,
AY	2014*		2015*		2016*		2017*		2018*		2019*		2020*		2021*		2022*		2023
2014	$	30,550	$	43,380	$	46,148	$	46,528	$	47,799	$	49,027	$	49,259	$	49,317	$	49,339	$	49,400
2015				32,184		49,348		50,197		51,290		52,078		52,342		52,400		53,208		53,369
2016						33,134		46,921		51,371		53,006		54,328		54,747		55,215		55,247
2017								41,314		66,818		74,415		78,360		80,581		80,958		80,965
2018										37,048		68,264		72,357		75,253		76,378		77,696
2019												30,703		51,740		55,092		57,038		59,015
2020														43,192		79,660		88,401		96,350
2021																57,272		89,174		99,671
2022																		44,667		84,235
2023																				111,137
		* Presented as unaudited required supplementary information.																Total	$	767,085
										All outstanding liabilities before 2014, net of reinsurance										923
								Liabilities for losses and loss adjustment expenses, net of reinsurance											$	142,876

	Average Annual Percentage Payout of Incurred Losses by Age, Net of Reinsurance*
Years	1		2		3		4		5		6		7		8		9		10
		51.6%		31.3%		6.5%		3.5%		2.3%		1.2%		0.4%		0.6%		0.2%		0.1%

Surety
(in thousands, except number of claims)
	Incurred Losses and Loss Adjustment Expenses, Net of Reinsurance																				As of December 31, 2023
	For the Years Ended December 31,																						Cumulative
																							Number of
																							Reported
AY	2014*		2015*		2016*		2017*		2018*		2019*		2020*		2021*		2022*		2023		Total IBNR		Claims
2014	$	16,450	$	8,106	$	5,225	$	4,427	$	4,267	$	4,319	$	4,266	$	4,227	$	4,230	$	4,219	$	2	1,364
2015				16,958		12,957		11,113		10,456		9,792		9,521		9,275		8,580		8,586		27	1,253
2016						18,928		11,062		9,351		8,895		8,391		7,948		8,134		7,963		53	1,392
2017								16,127		8,641		8,798		8,116		8,034		7,769		7,644		67	1,869
2018										16,765		7,227		4,564		3,947		3,996		3,760		85	1,373
2019												14,785		7,205		5,053		4,062		3,453		390	1,205
2020														19,241		14,840		12,378		11,516		3,158	954
2021																18,540		11,724		12,127		7,411	907
2022																		20,185		11,490		6,192	951
2023																				21,242		19,993	468
																		Total	$	92,000

	Cumulative Paid Loss and Loss Adjustment Expenses, Net of Reinsurance
	For the Years Ended December 31,
AY	2014*		2015*		2016*		2017*		2018*		2019*		2020*		2021*		2022*		2023
2014	$	722	$	4,283	$	4,166	$	4,059	$	4,131	$	4,234	$	4,214	$	4,197	$	4,218	$	4,213
2015				3,192		6,719		7,695		9,436		9,183		9,186		9,168		8,462		8,575
2016						3,087		5,817		6,299		7,640		8,086		7,673		7,946		7,795
2017								979		2,862		7,062		7,221		7,362		7,372		7,342
2018										1,835		2,588		2,368		2,536		3,020		2,079
2019												336		2,433		2,765		3,039		3,093
2020														835		2,719		3,828		3,907
2021																1,197		3,229		3,075
2022																		(241)		4,161
2023																				841
		* Presented as unaudited required supplementary information.																Total	$	45,081
										All outstanding liabilities before 2014, net of reinsurance										(106)
								Liabilities for losses and loss adjustment expenses, net of reinsurance											$	46,813

	Average Annual Percentage Payout of Incurred Losses by Age, Net of Reinsurance*
Years	1		2		3		4		5		6		7		8		9		10
		18.3%		37.4%		10.2%		7.1%		3.4%		(5.5)%		0.6%		(3.5)%		0.9%		(0.1)%

Schedule of Reconciliation of the Net Incurred and Paid Loss Development Tables to the Liability for Unpaid Losses and Settlement Expenses in the Consolidated Balance Sheet

The following is a reconciliation of the net incurred and paid loss development tables to the liability for unpaid losses and settlement expenses in the consolidated balance sheet:

(in thousands)	December 31, 2023		December 31, 2022
Net outstanding liabilities:
Casualty - Primary Occurrence	$	482,569	$	461,527
Casualty - Excess Occurrence		556,978		467,592
Casualty - Claims Made		207,564		211,296
Casualty - Transportation		148,226		141,737
Property		142,876		149,901
Surety		46,813		40,116
Unallocated loss adjustment expenses		66,111		61,752
Allowance for uncollectible reinsurance balances recoverable on unpaid losses and settlement expenses		10,608		11,250
Other		26,931		30,377
Liabilities for unpaid loss and settlement expenses, net of reinsurance	$	1,688,676	$	1,575,548
Reinsurance recoverable on unpaid claims:
Casualty - Primary Occurrence	$	53,177	$	46,674
Casualty - Excess Occurrence		149,502		138,822
Casualty - Claims Made		292,803		298,930
Casualty - Transportation		68,126		78,456
Property		152,714		137,613
Surety		51,526		50,737
Allowance for uncollectible reinsurance balances recoverable on unpaid losses and settlement expenses		(10,608)		(11,250)
Other		109		107
Total reinsurance balances recoverable on unpaid losses and settlement expenses	$	757,349	$	740,089
Total gross liability for unpaid loss and settlement expenses	$	2,446,025	$	2,315,637

Schedule of Prior Accident Years' Loss Reserve Development by Segment

The following table summarizes our prior accident years’ loss reserve development by segment for 2023, 2022 and 2021:

(in thousands)	2023		2022		2021
Casualty	$	(78,498)	$	(87,225)	$	(108,632)
Property		(21,196)		(24,927)		(10,981)
Surety		(8,853)		(10,427)		(5,850)
Total	$	(108,547)	$	(122,579)	$	(125,463)

Schedule of Paid and Unpaid Environmental, Asbestos and Mass Tort Claims Data (Including Incurred but not Reported Losses)

The following table represents paid and unpaid environmental, asbestos and mass tort claims data (including incurred but not reported losses) as of December 31, 2023, 2022 and 2021:

(in thousands)	2023		2022		2021
Loss and LAE Payments (Cumulative):
Gross	$	144,882	$	142,377	$	141,768
Ceded		(70,130)		(69,696)		(69,576)
Net	$	74,752	$	72,681	$	72,192
Unpaid Losses and LAE at End of Year:
Gross	$	25,180	$	26,871	$	25,747
Ceded		(5,490)		(5,786)		(5,718)
Net	$	19,690	$	21,085	$	20,029