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Short Duration Contracts (Tables)

12 Months Ended

Dec. 31, 2025

Short Duration Contracts Disclosure [Abstract]

Levels of disaggregation

The Company’s reserves for losses and loss adjustment expenses primarily relate to short-duration contracts with various characteristics (e.g., type of coverage, geography, claims duration). The Company considered such information in determining the level of disaggregation for disclosures related to its short-duration contracts, as detailed in the table below:

Reportable segment

Level of disaggregation

Included lines of business

Insurance

Property energy, marine and aviation

Property energy, marine and aviation

Third party occurrence business

Excess and surplus casualty (excluding contract binding); construction and national accounts; and other (including alternative market risks, excess workers’ compensation and employer’s liability insurance coverages)

Third party claims-made business

Professional lines

Multi-line and other specialty

Programs; contract binding (part of excess and surplus casualty); travel, accident and health; warranty and lenders solutions; and other (contract and commercial surety coverages); MCE business1

Reinsurance

Casualty

Casualty

Property catastrophe

Property catastrophe

Property excluding property catastrophe

Property excluding property catastrophe

Marine and aviation

Marine and aviation

Specialty

Specialty

Mortgage

Direct mortgage insurance in the U.S.

Mortgage insurance on U.S. primary exposures

(1) Includes business underwritten under a new business reinsurance agreement related to the MCE Acquisition. See note 2.

Reconciliation of claims development to liability

The following table represents a reconciliation of the disclosures of net incurred and paid loss development tables to the reserve for losses and loss adjustment expenses at December 31, 2025:

			December 31, 2025
Net outstanding liabilities
Insurance
Property, energy, marine and aviation			$	975
Third party occurrence business			4,454
Third party claims-made business			2,814
Multi-line and other specialty			2,827
Reinsurance
Casualty			3,785
Property catastrophe			920
Property excluding property catastrophe			2,103
Marine and aviation			612
Specialty			3,669
Mortgage
U.S. primary			311
Other short duration lines not included in disclosures (1)			1,436
Total for short duration lines			23,906
Unpaid losses and loss adjustment expenses recoverable
Insurance
Property, energy, marine and aviation			456
Third party occurrence business			2,893
Third party claims-made business			907
Multi-line and other specialty			436
Reinsurance
Casualty			861
Property catastrophe			911
Property excluding property catastrophe			362
Marine and aviation			549
Specialty			1,386
Mortgage
U.S. primary			42
Other short duration lines not included in disclosures (2)			271
Intercompany eliminations			(20)
Total for short duration lines			9,054
Lines other than short duration			136
Discounting			(78)
Unallocated claims adjustment expenses			529
			587
Reserve for losses and loss adjustment expenses			$	33,547

(1)    Includes amounts primarily associated with the loss portfolio reinsurance agreement related to the MCE Acquisition. See note 2.

(2)    Includes unpaid loss and loss adjustment expenses recoverable of $121 million related to the loss portfolio transfer reinsurance agreements.

Insurance

Claims Development [Line Items]

Claims development tables

The following tables present information on the insurance segment’s short-duration insurance contracts:

Property, energy, marine and aviation (in millions except claim count)
Incurred losses and allocated loss adjustment expenses, net of reinsurance																																																																		December 31, 2025
																																																																		Total of IBNR liabilities plus expected development on reported claims						Cumulative number of reported claims
						Year ended December 31,
Accident year						2016 unaudited						2017 unaudited						2018 unaudited						2019 unaudited						2020 unaudited						2021 unaudited						2022 unaudited						2023 unaudited						2024 unaudited						2025
2016						$	104					$	101					$	105					$	100					$	96					$	92					$	87					$	87					$	86					$	86					$	—					6,189
2017												281						246						236						230						231						225						225						224						225						—						6,512
2018																		181						186						174						170						170						172						170						171						—						5,091
2019																								179						179						165						161						159						156						156						(2)						7,518
2020																														359						329						336						333						337						335						1						8,558
2021																																				427						429						423						421						420						12						10,380
2022																																										522						495						576						679						91						16,853
2023																																																571						510						483						48						22,016
2024																																																						703						607						142						25,054
2025																																																												693						327						21,693
																																																						Total						$	3,855
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance
2016						$	25					$	83					$	98					$	97					$	94					$	91					$	87					$	87					$	86					$	86
2017												30						140						195						212						216						218						220						221						223
2018																		30						102						135						143						150						154						157						162
2019																								26						105						134						139						148						153						155
2020																														56						194						251						293						306						317
2021																																				90						268						343						365						396
2022																																										100						276						337						547
2023																																																146						271						378
2024																																																						195						363
2025																																																												267
																														Total																														2,894
																														All outstanding liabilities before 2016, net of reinsurance																														14
																								Liabilities for losses and loss adjustment expenses, net of reinsurance																																				$	975

Third party occurrence business (in millions except claim count)
						Incurred losses and allocated loss adjustment expenses, net of reinsurance																																																												December 31, 2025
																																																																		Total of IBNR liabilities plus expected development on reported claims						Cumulative number of reported claims
						Year ended December 31,
Accident year						2016 unaudited						2017 unaudited						2018 unaudited						2019 unaudited						2020 unaudited						2021 unaudited						2022 unaudited						2023 unaudited						2024 unaudited						2025
2016						$	389					$	394					$	406					$	399					$	375					$	367					$	363					$	352					$	345					$	331					$	49					78,399
2017												417						417						422						412						407						406						404						408						398						72						84,591
2018																		430						453						450						451						459						461						448						435						84						79,101
2019																								456						487						480						471						470						451						439						80						87,700
2020																														606						616						640						632						606						594						91						92,035
2021																																				622						662						659						671						688						66						94,124
2022																																										687						726						735						737						300						95,570
2023																																																877						936						936						482						100,702
2024																																																						1,001						1,038						756						103,711
2025																																																												1,153						1,022						79,110
																																																						Total						$	6,749
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance
2016						$	12					$	42					$	87					$	137					$	164					$	195					$	215					$	230					$	246					$	252
2017												13						52						100						135						165						221						247						271						289
2018																		17						64						115						154						200						247						271						289
2019																								18						73						122						173						214						255						282
2020																														24						76						155						235						318						374
2021																																				26						91						174						323						444
2022																																										24						85						186						294
2023																																																32						156						264
2024																																																						37						136
2025																																																												46
																														Total																														2,670
																														All outstanding liabilities before 2016, net of reinsurance																														375
																								Liabilities for losses and loss adjustment expenses, net of reinsurance																																				$	4,454

Third party claims-made business (in millions except claim count)
Incurred losses and allocated loss adjustment expenses, net of reinsurance																																																																		December 31, 2025
																																																																		Total of IBNR liabilities plus expected development on reported claims						Cumulative number of reported claims
						Year ended December 31,
Accident year						2016 unaudited						2017 unaudited						2018 unaudited						2019 unaudited						2020 unaudited						2021 unaudited						2022 unaudited						2023 unaudited						2024 unaudited						2025
2016						$	275					$	291					$	308					$	314					$	322					$	327					$	329					$	327					$	329					$	325					$	8					15,135
2017												270						285						311						308						323						316						337						339						326						23						15,712
2018																		272						314						319						335						347						366						366						362						22						17,304
2019																								288						317						317						321						329						329						326						34						17,428
2020																														383						412						423						445						432						419						54						17,580
2021																																				514						517						498						461						446						119						19,120
2022																																										668						654						589						570						186						21,348
2023																																																809						895						901						375						26,037
2024																																																						736						777						432						29,857
2025																																																												882						736						29,188
																																																						Total						$	5,334
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance
2016						$	11					$	68					$	127					$	158					$	205					$	242					$	257					$	295					$	296					$	304
2017												9						67						113						143						196						232						257						276						284
2018																		12						68						118						158						208						258						285						305
2019																								12						65						122						154						196						235						254
2020																														17						87						151						214						265						309
2021																																				23						90						162						223						269
2022																																										25						100						218						307
2023																																																64						200						332
2024																																																						56						196
2025																																																												49
																														Total																														2,609
																														All outstanding liabilities before 2016, net of reinsurance																														89
																								Liabilities for losses and loss adjustment expenses, net of reinsurance																																				$	2,814

Multi-line and other specialty (in millions except claim count)
Incurred losses and allocated loss adjustment expenses, net of reinsurance																																																																		December 31, 2025
																																																																		Total of IBNR liabilities plus expected development on reported claims						Cumulative number of reported claims
						Year ended December 31,
Accident year						2016 unaudited						2017 unaudited						2018 unaudited						2019 unaudited						2020 unaudited						2021 unaudited						2022 unaudited						2023 unaudited						2024 unaudited						2025
2016						$	408					$	430					$	427					$	416					$	410					$	408					$	408					$	406					$	404					$	403					$	3					196,531
2017												482						500						491						500						504						512						515						514						516						4						235,002
2018																		512						564						562						564						564						564						564						566						6						265,421
2019																								566						611						639						650						656						670						666						8						247,961
2020																														616						567						513						515						519						519						22						170,515
2021																																				634						618						613						634						643						33						137,791
2022																																										677						640						639						624						64						156,572
2023																																																815						809						823						133						176,315
2024																																																						1,419						1,442						508						200,279
2025																																																												1,987						1,195						140,332
																																																						Total						$	8,189
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance
2016						$	176					$	304					$	341					$	362					$	379					$	385					$	390					$	391					$	396					$	397
2017												181						342						380						423						446						472						479						493						499
2018																		211						388						442						479						508						526						543						550
2019																								212						385						486						548						576						611						629
2020																														171						308						358						405						450						469
2021																																				157						334						427						511						557
2022																																										177						370						439						491
2023																																																253						489						588
2024																																																						336						727
2025																																																												493
																														Total																														5,400
																														All outstanding liabilities before 2016, net of reinsurance																														38
																								Liabilities for losses and loss adjustment expenses, net of reinsurance																																				$	2,827

Percentage annual payout by age

The following table presents the average annual percentage payout of incurred losses and allocated loss adjustment expenses by age, net of reinsurance, as of December 31, 2025:

						Average annual percentage payout of incurred losses and allocated loss adjustment expenses by age, net of reinsurance
						Year 1						Year 2						Year 3						Year 4						Year 5						Year 6						Year 7						Year 8						Year 9						Year 10
Property, energy, marine and aviation						23.0		%				41.4		%				18.2		%				8.9		%				3.3		%				1.0		%				—		%				1.1		%				(0.1)		%				0.1		%
Third party occurrence business						3.7		%				10.1		%				12.4		%				13.4		%				11.3		%				10.5		%				6.1		%				5.0		%				4.6		%				2.0		%
Third party claims-made business						4.7		%				16.1		%				16.3		%				12.0		%				13.3		%				11.8		%				6.4		%				7.7		%				1.3		%				2.4		%
Multi-line and other specialty						31.2		%				29.0		%				11.0		%				8.5		%				5.6		%				3.7		%				2.1		%				1.4		%				1.1		%				0.4		%

Reinsurance

Claims Development [Line Items]

Claims development tables

The following tables present information on the reinsurance segment’s short-duration insurance contracts:

Casualty (in millions)
Incurred losses and allocated loss adjustment expenses, net of reinsurance																																																																		December 31, 2025
																																																																		Total of IBNR liabilities plus expected development on reported claims						Cumulative number of reported claims
						Year ended December 31,
Accident year						2016 unaudited						2017 unaudited						2018 unaudited						2019 unaudited						2020 unaudited						2021 unaudited						2022 unaudited						2023 unaudited						2024 unaudited						2025
2016						$	216					$	228					$	252					$	267					$	274					$	273					$	277					$	285					$	287					$	289					$	45					N/A
2017												271						258						274						302						314						321						336						343						346						55						N/A
2018																		281						295						286						291						304						314						328						332						53						N/A
2019																								336						346						372						384						406						405						402						65						N/A
2020																														389						377						360						379						399						365						108						N/A
2021																																				444						438						428						428						464						163						N/A
2022																																										552						533						546						539						241						N/A
2023																																																664						669						695						385						N/A
2024																																																						734						776						624						N/A
2025																																																												1,002						928						N/A
																																																						Total						$	5,210
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance
2016						$	6					$	26					$	52					$	87					$	114					$	133					$	158					$	174					$	188					$	197
2017												6						30						64						113						138						165						190						224						239
2018																		8						31						107						129						155						183						207						224
2019																								16						58						97						131						220						258						287
2020																														18						51						90						132						178						202
2021																																				15						54						103						191						236
2022																																										18						62						114						182
2023																																																19						88						173
2024																																																						14						66
2025																																																												25
																																																						Total						1,831
																														All outstanding liabilities before 2016, net of reinsurance																														406
																								Liabilities for losses and loss adjustment expenses, net of reinsurance																																				$	3,785

Property catastrophe (in millions)
Incurred losses and allocated loss adjustment expenses, net of reinsurance																																																																		December 31, 2025
																																																																		Total of IBNR liabilities plus expected development on reported claims						Cumulative number of reported claims
						Year ended December 31,
Accident year						2016 unaudited						2017 unaudited						2018 unaudited						2019 unaudited						2020 unaudited						2021 unaudited						2022 unaudited						2023 unaudited						2024 unaudited						2025
2016						$	23					$	16					$	12					$	9					$	6					$	6					$	5					$	4					$	4					$	4					$	—					N/A
2017												86						54						50						36						24						21						21						21						20						—						N/A
2018																		69						44						25						12						3						—						(2)						(4)						—						N/A
2019																								12						4						4						(4)						(11)						(7)						(8)						1						N/A
2020																														272						337						341						330						319						321						5						N/A
2021																																				323						318						305						307						302						11						N/A
2022																																										306						298						273						262						30						N/A
2023																																																272						272						227						18						N/A
2024																																																						512						441						67						N/A
2025																																																												415						84						N/A
																																																						Total						$	1,980
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance
2016						$	(7)					$	2					$	2					$	3					$	2					$	2					$	2					$	2					$	2					$	3
2017												31						32						37						27						14						16						17						17						17
2018																		27						2						12						(17)						(14)						(13)						(11)						(12)
2019																								4						4						8						(17)						(16)						(25)						(26)
2020																														57						158						208						251						262						271
2021																																				66						177						230						239						243
2022																																										70						169						211						219
2023																																																8						84						120
2024																																																						60						145
2025																																																												82
																																																						Total						1,062
																														All outstanding liabilities before 2016, net of reinsurance																														2
																								Liabilities for losses and loss adjustment expenses, net of reinsurance																																				$	920

Property excluding property catastrophe (in millions)
Incurred losses and allocated loss adjustment expenses, net of reinsurance																																																																		December 31, 2025
																																																																		Total of IBNR liabilities plus expected development on reported claims						Cumulative number of reported claims
						Year ended December 31,
Accident year						2016 unaudited						2017 unaudited						2018 unaudited						2019 unaudited						2020 unaudited						2021 unaudited						2022 unaudited						2023 unaudited						2024 unaudited						2025
2016						$	174					$	144					$	136					$	135					$	138					$	135					$	129					$	130					$	127					$	124					$	3					N/A
2017												267						250						237						230						213						205						202						201						197						6						N/A
2018																		223						239						235						212						202						203						203						197						3						N/A
2019																								216						206						195						190						190						196						193						11						N/A
2020																														368						339						319						320						322						313						(1)						N/A
2021																																				546						497						491						499						500						14						N/A
2022																																										745						670						660						656						70						N/A
2023																																																839						740						744						117						N/A
2024																																																						1,212						1,056						325						N/A
2025																																																												1,170						648						N/A
																																																						Total						$	5,150
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance
2016						$	33					$	94					$	98					$	103					$	111					$	113					$	114					$	114					$	117					$	116
2017												28						124						155						164						178						182						186						186						186
2018																		30						107						151						167						175						177						177						181
2019																								43						124						150						162						169						170						174
2020																														101						207						243						266						280						291
2021																																				136						269						363						424						457
2022																																										142						360						468						526
2023																																																151						382						489
2024																																																						144						445
2025																																																												190
																																																						Total						3,055
																														All outstanding liabilities before 2016, net of reinsurance																														8
																								Liabilities for losses and loss adjustment expenses, net of reinsurance																																				$	2,103

Marine and aviation (in millions)
Incurred losses and allocated loss adjustment expenses, net of reinsurance																																																																		December 31, 2025
																																																																		Total of IBNR liabilities plus expected development on reported claims						Cumulative number of reported claims
						Year ended December 31,
Accident year						2016 unaudited						2017 unaudited						2018 unaudited						2019 unaudited						2020 unaudited						2021 unaudited						2022 unaudited						2023 unaudited						2024 unaudited						2025
2016						$	27					$	23					$	23					$	19					$	17					$	15					$	12					$	11					$	11					$	10					$	2					N/A
2017												29						26						24						21						20						17						15						15						15						2						N/A
2018																		27						25						24						24						21						21						20						19						2						N/A
2019																								48						55						60						61						62						63						60						6						N/A
2020																														83						76						80						80						82						81						4						N/A
2021																																				110						96						82						79						86						8						N/A
2022																																										126						138						134						167						38						N/A
2023																																																161						170						156						44						N/A
2024																																																						233						220						100						N/A
2025																																																												227						172						N/A
																																																						Total						$	1,041
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance
2016						$	(7)					$	(2)					$	—					$	3					$	6					$	7					$	7					$	7					$	7					$	8
2017												2						7						9						11						12						12						12						12						12
2018																		2						7						11						13						14						15						16						16
2019																								11						22						29						35						43						49						49
2020																														9						26						42						60						66						71
2021																																				8						24						45						53						68
2022																																										12						37						63						86
2023																																																13						43						77
2024																																																						18						44
2025																																																												16
																																																						Total						447
																														All outstanding liabilities before 2016, net of reinsurance																														18
																								Liabilities for losses and loss adjustment expenses, net of reinsurance																																				$	612

Specialty (in millions)
Incurred losses and allocated loss adjustment expenses, net of reinsurance																																																																		December 31, 2025
																																																																		Total of IBNR liabilities plus expected development on reported claims						Cumulative number of reported claims
						Year ended December 31,
Accident year						2016 unaudited						2017 unaudited						2018 unaudited						2019 unaudited						2020 unaudited						2021 unaudited						2022 unaudited						2023 unaudited						2024 unaudited						2025
2016						$	338					$	335					$	328					$	319					$	326					$	321					$	318					$	319					$	312					$	315					$	6					N/A
2017												412						405						385						386						384						379						376						372						378						11						N/A
2018																		431						423						417						442						438						438						431						425						16						N/A
2019																								441						418						412						408						418						413						398						25						N/A
2020																														607						536						531						551						543						532						36						N/A
2021																																				628						629						630						637						638						33						N/A
2022																																										962						942						991						950						108						N/A
2023																																																1,303						1,230						1,321						330						N/A
2024																																																						1,696						1,647						623						N/A
2025																																																												1,960						1,275						N/A
																																																						Total						$	8,564
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance
2016						$	113					$	213					$	251					$	271					$	288					$	295					$	301					$	305					$	304					$	305
2017												141						266						309						325						339						350						360						361						362
2018																		135						286						326						348						366						389						393						392
2019																								126						217						286						313						335						355						354
2020																														138						299						377						413						453						471
2021																																				156						319						443						508						546
2022																																										186						465						627						698
2023																																																207						502						714
2024																																																						331						705
2025																																																												383
																																																						Total						4,930
																														All outstanding liabilities before 2016, net of reinsurance																														35
																								Liabilities for losses and loss adjustment expenses, net of reinsurance																																				$	3,669

Percentage annual payout by age

The following table presents the average annual percentage payout of incurred losses and allocated loss adjustment expenses by age, net of reinsurance, as of December 31, 2025:

						Average annual percentage payout of incurred losses and allocated loss adjustment expenses by age, net of reinsurance
						Year 1						Year 2						Year 3						Year 4						Year 5						Year 6						Year 7						Year 8						Year 9						Year 10
Casualty						2.9		%				8.2		%				11.8		%				12.1		%				11.5		%				7.8		%				7.6		%				6.8		%				4.7		%				3.0		%
Property catastrophe						(62.4)		%				110.1		%				(23.8)		%				138.8		%				(24.8)		%				17.4		%				(4.8)		%				1.0		%				2.2		%				5.7		%
Property excluding property catastrophe						20.9		%				37.0		%				14.5		%				7.3		%				5.4		%				1.8		%				1.2		%				0.7		%				1.1		%				(0.7)		%
Marine and aviation						1.8		%				24.3		%				19.8		%				15.0		%				12.2		%				6.4		%				2.0		%				1.1		%				1.1		%				6.2		%
Specialty						26.2		%				28.2		%				14.6		%				6.7		%				5.4		%				3.8		%				1.2		%				0.5		%				—		%				0.1		%

Mortgage

Claims Development [Line Items]

Claims development tables

The following table presents information on the mortgage segment’s short-duration insurance contracts:

U.S. primary mortgage insurance (in millions except claim count)
Incurred losses and allocated loss adjustment expenses, net of reinsurance																																																																		December 31, 2025
																																																																					Total of IBNR liabilities plus expected development on reported claims						Cumulative number of paid claims
Year ended December 31,
Accident year						2016 unaudited						2017 unaudited						2018 unaudited						2019 unaudited						2020 unaudited						2021 unaudited						2022 unaudited						2023 unaudited									2024 unaudited						2025
2016						$	184					$	171					$	149					$	141					$	142					$	142					$	137					$	136								$	136					$	136					—						3,564
2017												179						132						107						108						109						102						99									99						97						—						2,723
2018																		132						96						89						88						72						69									69						66						—						1,990
2019																								108						119						110						63						51									52						48						—						1,491
2020																														420						374						78						33									31						26						—						904
2021																																				144						77						20									17						13						—						443
2022																																										173						55									30						22						—						604
2023																																																182									71						36						—						727
2024																																																									180						86						—						509
2025																																																															191						1						87
																																																									Total						$	721
Cumulative paid losses and allocated loss adjustment expenses, net of reinsurance
2016						11						72						113						127						131						132						132						133									134						135
2017												9						48						79						87						90						92						93									95						95
2018																		4						31						50						56						59						60									63						64
2019																								3						20						29						34						39									42						44
2020																														1						4						8						13									19						21
2021																																				—						2						5									8						10
2022																																										—						3									10						14
2023																																																—									7						18
2024																																																									1						16
2025																																																															2
																																																									Total						419
																														All outstanding liabilities before 2016, net of reinsurance																														9
																								Liabilities for losses and loss adjustment expenses, net of reinsurance																																				$	311

Percentage annual payout by age

The following table presents the average annual percentage payout of incurred losses and allocated loss adjustment expenses by age, net of reinsurance, as of December 31, 2025:

Average annual percentage payout of incurred losses and allocated loss adjustment expenses by age, net of reinsurance
						Year 1						Year 2						Year 3						Year 4						Year 5						Year 6						Year 7						Year 8						Year 9						Year 10
U.S. Primary						4.1		%				26.0		%				26.0		%				14.3		%				9.6		%				4.2		%				2.6		%				1.3		%				0.7		%				0.5		%

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