Property Casualty Loss and Loss Expenses (Tables)

12 Months Ended

Dec. 31, 2023

Insurance [Abstract]

Consolidated Property Casualty Loss And Loss Expense Reserves

This table summarizes activity for our consolidated property casualty loss and loss expense reserves:

(Dollars in millions)	Years ended December 31,
	2023		2022		2021
Gross loss and loss expense reserves, January 1	$	8,336	$	7,229	$	6,677
Less reinsurance recoverable	405		327		277
Net loss and loss expense reserves, January 1	7,931		6,902		6,400
Net incurred loss and loss expenses related to:
Current accident year	5,173		4,875		4,024
Prior accident years	(215)		(159)		(428)
Total incurred	4,958		4,716		3,596
Net paid loss and loss expenses related to:
Current accident year	1,875		1,592		1,379
Prior accident years	2,401		2,095		1,715
Total paid	4,276		3,687		3,094
Net loss and loss expense reserves, December 31	8,613		7,931		6,902
Plus reinsurance recoverable	362		405		327
Gross loss and loss expense reserves, December 31	$	8,975	$	8,336	$	7,229

Reconciliation of Property casualty Incurred Losses and ALAE and Paid Losses and ALAE Development Information

The following table provides a reconciliation of the property casualty incurred losses and allocated loss adjustment expenses (ALAE) development and paid losses and ALAE development information at December 31, 2023.

(Dollars in millions)	Cumulative incurred losses and ALAE as reported within the triangles, net of reinsurance		Cumulative paid losses and ALAE as reported within the triangles, net of reinsurance		Liabilities for loss and ALAE for accident years not presented in the triangles, net of reinsurance		Total liabilities for loss and ALAE, net of reinsurance		Reinsurance recoverable on unpaid losses		Total liabilities for gross loss and loss expense reserves
Commercial casualty	$	6,497	$	3,680	$	91	$	2,908	$	19	$	2,927
Workers' compensation	1,826		1,160		316		982		54		1,036
Commercial auto	2,432		1,657		32		807		4		811
Commercial property	3,496		3,033		12		475		50		525
Personal auto	1,884		1,594		12		302		25		327
Homeowner	2,576		2,231		6		351		(3)		348
Excess and surplus	1,545		707		4		842		33		875
Other lines											1,686
Total liabilities for loss and ALAE reserves											8,535
Unallocated loss adjustment expense reserves											440
Gross loss and loss expense reserves											$	8,975

Schedule of Incurred and Paid Losses and ALAE Development by Accident Year

The following table shows the commercial casualty incurred and paid losses and ALAE development by accident year. The table also shows the IBNR reserves plus expected development on reported losses and claim frequency:

(Dollars in millions, reported claims in thousands)																					As of December 31, 2023
Incurred losses and ALAE, net of reinsurance for the years ended December 31,																						Total of incurred but not reported liabilities plus expected development on reported losses		Cumulative number of reported claims
Accident	Unaudited
Year	2014		2015		2016		2017		2018		2019		2020		2021		2022		2023
2014	$	503	$	496	$	479	$	476	$	479	$	465	$	469	$	466	$	462	$	464		$	10	21
2015			533		526		529		516		508		502		504		496		513			14		22
2016					563		574		557		555		554		538		531		525			19		22
2017							610		597		577		571		555		554		553			29		21
2018									650		641		622		588		612		618			55		22
2019											672		643		607		669		682			80		21
2020													674		629		606		593			112		15
2021															714		697		697			265		14
2022																	924		902			453		13
2023																			950			729		8
Total																			$	6,497
Cumulative paid losses and ALAE, net of reinsurance
2014	$	34	$	97	$	172	$	287	$	338	$	390	$	409	$	421	$	437	$	447
2015			38		108		200		287		362		404		424		453		471
2016					46		126		228		331		395		434		466		485
2017							48		122		234		320		392		437		486
2018									44		148		253		345		441		505
2019											39		134		259		394		503
2020													33		102		242		345
2021															31		123		251
2022																	37		141
2023																			46
Total																			3,680
All outstanding liabilities before 2014, net of reinsurance																			91
Liabilities for loss and ALAE, net of reinsurance																			$	2,908

The following table shows the workers’ compensation incurred and paid losses and ALAE development by accident year. The table also shows the IBNR reserves plus expected development on reported losses and claim frequency:

(Dollars in millions, reported claims in thousands)																					As of December 31, 2023
Incurred losses and ALAE, net of reinsurance for the years ended December 31,																						Total of incurred but not reported liabilities plus expected development on reported losses		Cumulative number of reported claims
Accident	Unaudited
Year	2014		2015		2016		2017		2018		2019		2020		2021		2022		2023
2014	$	261	$	233	$	214	$	203	$	201	$	198	$	197	$	202	$	202	$	203		$	15	19
2015			246		220		208		195		179		173		173		171		167			20		17
2016					230		218		206		188		183		183		183		181			22		16
2017							218		208		190		183		172		167		160			21		15
2018									222		207		199		186		179		175			26		15
2019											224		215		202		188		178			31		14
2020													204		190		172		153			39		11
2021															202		190		183			42		11
2022																	209		205			65		11
2023																			221			106		9
Total																			$	1,826
Cumulative paid losses and ALAE, net of reinsurance
2014	$	56	$	110	$	134	$	148	$	157	$	162	$	165	$	168	$	171	$	172
2015			47		93		115		129		134		137		139		139		140
2016					46		97		119		131		141		146		148		150
2017							45		88		106		114		119		122		126
2018									48		95		115		127		133		135
2019											49		94		115		122		129
2020													37		68		82		96
2021															37		82		100
2022																	37		76
2023																			36
Total																			1,160
All outstanding liabilities before 2014, net of reinsurance																			316
Liabilities for loss and ALAE, net of reinsurance																			$	982

The following table shows the commercial auto incurred and paid losses and ALAE development by accident year. The table also shows the IBNR reserves plus expected development on reported losses and claim frequency:

(Dollars in millions, reported claims in thousands)											As of December 31, 2023
Incurred losses and ALAE, net of reinsurance for the years ended December 31,												Total of incurred but not reported liabilities plus expected development on reported losses		Cumulative number of reported claims
Accident	Unaudited
Year	2019		2020		2021		2022		2023
2019	$	452	$	451	$	453	$	469	$	471		$	7	46
2020			424		391		384		377			16		36
2021					470		477		465			51		39
2022							558		569			105		41
2023									550			203		34
Total									$	2,432
Cumulative paid losses and ALAE, net of reinsurance
2019	$	183	$	268	$	333	$	395	$	435
2020			154		214		280		328
2021					179		278		346
2022							217		332
2023									216
Total									1,657
All outstanding liabilities before 2019, net of reinsurance									32
Liabilities for loss and ALAE, net of reinsurance									$	807

The following table shows the commercial property incurred and paid losses and ALAE development by accident year. The table also shows the IBNR reserves plus expected development on reported losses and claim frequency:

(Dollars in millions, reported claims in thousands)											As of December 31, 2023
Incurred losses and ALAE, net of reinsurance for the years ended December 31,												Total of incurred but not reported liabilities plus expected development on reported losses		Cumulative number of reported claims
Accident	Unaudited
Year	2019		2020		2021		2022		2023
2019	$	621	$	606	$	600	$	598	$	592		$	3	17
2020			855		742		719		716			22		24
2021					607		586		576			5		14
2022							813		779			24		16
2023									833			92		12
Total									$	3,496
Cumulative paid losses and ALAE, net of reinsurance
2019	$	413	$	561	$	579	$	590	$	591
2020			489		637		672		687
2021					326		527		558
2022							393		691
2023									506
Total									3,033
All outstanding liabilities before 2019, net of reinsurance									12
Liabilities for loss and ALAE, net of reinsurance									$	475

The following table shows the personal auto incurred and paid losses and ALAE development by accident year. The table also shows the IBNR reserves plus expected development on reported losses and claim frequency:

(Dollars in millions, reported claims in thousands)											As of December 31, 2023
Incurred losses and ALAE, net of reinsurance for the years ended December 31,												Total of incurred but not reported liabilities plus expected development on reported losses		Cumulative number of reported claims
Accident	Unaudited
Year	2019		2020		2021		2022		2023
2019	$	399	$	383	$	380	$	383	$	381		$	2	102
2020			305		281		277		277			3		71
2021					350		343		342			6		80
2022							427		418			15		86
2023									466			72		86
Total									$	1,884
Cumulative paid losses and ALAE, net of reinsurance
2019	$	250	$	314	$	346	$	363	$	373
2020			186		225		248		264
2021					219		278		304
2022							277		349
2023									304
Total									1,594
All outstanding liabilities before 2019, net of reinsurance									12
Liabilities for loss and ALAE, net of reinsurance									$	302

The following table shows the homeowner incurred and paid losses and ALAE development by accident year. The table also shows the IBNR reserves plus expected development on reported losses and claim frequency:

(Dollars in millions, reported claims in thousands)											As of December 31, 2023
Incurred losses and ALAE, net of reinsurance for the years ended December 31,												Total of incurred but not reported liabilities plus expected development on reported losses		Cumulative number of reported claims
Accident	Unaudited
Year	2019		2020		2021		2022		2023
2019	$	432	$	421	$	422	$	418	$	418		$	2	22
2020			497		475		470		471			3		23
2021					495		449		440			4		19
2022							552		505			21		20
2023									742			116		21
Total									$	2,576
Cumulative paid losses and ALAE, net of reinsurance
2019	$	303	$	391	$	407	$	411	$	414
2020			326		434		453		464
2021					285		405		424
2022							299		461
2023									468
Total									2,231
All outstanding liabilities before 2019, net of reinsurance									6
Liabilities for loss and ALAE, net of reinsurance									$	351

The following table shows the excess and surplus lines incurred and paid losses and ALAE development by accident year. The table also shows the IBNR reserves plus expected development on reported losses and claim frequency:

(Dollars in millions, reported claims in thousands)																			As of December 31, 2023
Incurred losses and ALAE, net of reinsurance for the years ended December 31,																						Total of incurred but not reported liabilities plus expected development on reported losses		Cumulative number of reported claims
Accident	Unaudited
Year	2014		2015		2016		2017		2018		2019		2020		2021		2022			2023
2014	$	95	$	82	$	75	$	64	$	60	$	59	$	59	$	58	$	56		$	57	$	—	2
2015			96		81		73		67		65		66		65		61			65		—		2
2016					93		87		84		82		90		91		88			89		2		3
2017							104		95		95		94		94		91			94		4		3
2018									116		109		110		108		107			105		6		3
2019											137		135		141		139			142		16		3
2020													172		172		160			152		26		4
2021															217		235			233		66		4
2022																	294			280		134		3
2023																				328		251		2
Total																				$	1,545
Cumulative paid losses and ALAE, net of reinsurance
2014	$	9	$	17	$	27	$	37	$	43	$	48	$	51	$	53	$	55		$	55
2015			8		19		29		41		51		54		56		58			62
2016					10		21		39		51		62		75		81			83
2017							11		23		41		57		68		77			88
2018									11		26		50		62		75			88
2019											13		34		55		79			102
2020													16		37		56			86
2021															17		45			82
2022																	21			46
2023																				15
Total																				707
All outstanding liabilities before 2014, net of reinsurance																				4
Liabilities for loss and ALAE, net of reinsurance																				$	842

Schedule of Average Annual Percentage Payout of Incurred Claims

The following table shows the average annual percentage payout of incurred losses for the commercial casualty line of business:

Average annual percentage payout of incurred losses by age, net of reinsurance (unaudited)
Years	1	2	3	4	5	6	7	8	9	10
Average annual percentage payout	6.4%	13.7%	18.9%	18.4%	13.8%	9.1%	5.7%	4.0%	3.5%	2.1%

The following table shows the average annual percentage payout of incurred losses for the workers’ compensation line of business:

Average annual percentage payout of incurred losses by age, net of reinsurance (unaudited)
Years	1	2	3	4	5	6	7	8	9	10
Average annual percentage payout	24.3%	25.2%	11.3%	6.6%	3.9%	2.1%	1.6%	0.8%	0.8%	0.9%

The following table shows the average annual percentage payout of incurred losses for the commercial auto line of business. Commercial auto includes both physical damage and liability losses. A majority of the incurred losses paid after year 2 are the result of liability losses.

Average annual percentage payout of incurred losses by age, net of reinsurance (unaudited)
Years	1	2	3	4	5
Average annual percentage payout	39.1%	18.9%	15.3%	12.8%	8.6%

The following table shows the average annual percentage payout of incurred losses for the commercial property line of business:

Average annual percentage payout of incurred losses by age, net of reinsurance (unaudited)
Years	1	2	3	4	5
Average annual percentage payout	61.1%	29.7%	4.5%	2.0%	—%

The following table shows the average annual percentage payout of incurred losses for the personal auto line of business. Personal auto includes both physical damage and liability losses. A majority of the incurred losses paid after year 2 are the result of liability losses.

Average annual percentage payout of incurred losses by age, net of reinsurance (unaudited)
Years	1	2	3	4	5
Average annual percentage payout	65.6%	16.4%	8.2%	5.0%	2.4%

The following table shows the average annual percentage payout of incurred losses for the homeowner line of business:

Average annual percentage payout of incurred losses by age, net of reinsurance (unaudited)
Years	1	2	3	4	5
Average annual percentage payout	65.8%	25.8%	4.1%	1.6%	0.6%

The following table shows the average annual percentage payout of incurred losses for the excess and surplus lines insurance segment. Excess and surplus lines consist mostly of commercial casualty and commercial property coverages. A majority of the incurred losses paid after year 2 are the result of commercial casualty losses.

Average annual percentage payout of incurred losses by age, net of reinsurance (unaudited)
Years	1	2	3	4	5	6	7	8	9	10
Average annual percentage payout	10.1%	13.2%	17.4%	16.2%	13.1%	10.4%	6.3%	2.7%	4.3%	1.1%