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Investments (Tables)

9 Months Ended

Sep. 30, 2025

Investments [Abstract]

Schedule of Available-for-Sale Securities

Information regarding our AFS securities as of September 30, 2025 and December 31, 2024, were as follows:

September 30, 2025						Cost/ Amortized Cost						Allowance for Credit Losses						Unrealized Gains						Unrealized Losses						Fair Value
($ in thousands)
AFS fixed income securities:
U.S. government and government agencies						$	158,593					—						134						(15,329)						143,398
Foreign government						10,784						(19)						49						(829)						9,985
Obligations of states and political subdivisions						580,895						(326)						5,977						(25,586)						560,960
Corporate securities						3,366,977						(8,020)						74,035						(73,730)						3,359,262
Collateralized loan obligations ("CLO") and other asset-backed securities ("ABS")						2,495,028						(9,234)						29,936						(36,989)						2,478,741
Residential mortgage-backed securities ("RMBS")						2,060,837						(11,368)						18,184						(68,720)						1,998,933
Commercial mortgage-backed securities ("CMBS")						736,239						(109)						5,272						(17,257)						724,145
Total AFS fixed income securities						$	9,409,353					(29,076)						133,587						(238,440)						9,275,424

December 31, 2024						Cost/ Amortized Cost						Allowance for Credit Losses						Unrealized Gains						Unrealized Losses						Fair Value
($ in thousands)
AFS fixed income securities:
U.S. government and government agencies						$	139,906					—						2						(19,753)						120,155
Foreign government						10,656						(21)						—						(1,333)						9,302
Obligations of states and political subdivisions						483,609						(570)						550						(32,359)						451,230
Corporate securities						3,181,046						(14,924)						25,259						(123,201)						3,068,180
CLO and other ABS						2,065,611						(4,889)						22,116						(49,689)						2,033,149
RMBS						1,812,744						(11,544)						3,880						(112,722)						1,692,358
CMBS						782,506						—						1,478						(31,024)						752,960
Total AFS fixed income securities						$	8,476,078					(31,948)						53,285						(370,081)						8,127,334

Schedule of Debt Securities, Available-for-Sale, Allowance for Credit Loss

The following tables provide a roll forward of the allowance for credit losses on our AFS fixed income securities for the indicated periods:

Quarter ended September 30, 2025						Beginning Balance						Current Provision for Securities without Prior Allowance						Initial Allowance for Purchased Credit Deteriorated Assets with Credit Deterioration						Increase (Decrease) on Securities with Prior Allowance, excluding intent (or Requirement) to Sell Securities						Reductions for Securities Sold						Reductions for Securities Identified as Intent (or Requirement) to Sell during the Period						Ending Balance
($ in thousands)
Foreign government						$	21					—						—						(2)						—						—						19
Obligations of states and political subdivisions						390						13						—						(77)						—						—						326
Corporate securities						9,571						369						—						(1,568)						(352)						—						8,020
CLO and other ABS						7,230						333						1,938						68						(335)						—						9,234
RMBS						11,422						—						—						25						(79)						—						11,368
CMBS						99						—						—						10						—						—						109
Total AFS fixed income securities						$	28,733					715						1,938						(1,544)						(766)						—						29,076

Quarter ended September 30, 2024						Beginning Balance						Current Provision for Securities without Prior Allowance						Initial Allowance for Purchased Credit Deteriorated Assets with Credit Deterioration						Increase (Decrease) on Securities with Prior Allowance, excluding intent (or Requirement) to Sell Securities						Reductions for Securities Sold						Reductions for Securities Identified as Intent (or Requirement) to Sell during the Period						Ending Balance
($ in thousands)
Foreign government						$	26					—						—						(2)						—						—						24
Obligations of states and political subdivisions						639						107						—						(266)						(8)						—						472
Corporate securities						15,950						747						—						(4,231)						(432)						—						12,034
CLO and other ABS						3,022						1,575						—						(49)						(86)						—						4,462
RMBS						11,660						—						—						(63)						(88)						—						11,509
CMBS						12						—						—						(9)						—						—						3
Total AFS fixed income securities						$	31,309					2,429						—						(4,620)						(614)						—						28,504

Nine Months ended September 30, 2025						Beginning Balance						Current Provision for Securities without Prior Allowance						Initial Allowance for Purchased Credit Deteriorated Assets with Credit Deterioration						Increase (Decrease) on Securities with Prior Allowance, excluding intent (or Requirement) to Sell Securities						Reductions for Securities Sold						Reductions for Securities Identified as Intent (or Requirement) to Sell during the Period						Ending Balance
($ in thousands)
Foreign government						$	21					—						—						(2)						—						—						19
Obligations of states and political subdivisions						570						18						—						(156)						(106)						—						326
Corporate securities						14,924						957						—						(6,363)						(1,498)						—						8,020
CLO and other ABS						4,889						2,177						1,938						752						(522)						—						9,234
RMBS						11,544						—						—						163						(339)						—						11,368
CMBS						—						109						—						—						—						—						109
Total AFS fixed income securities						$	31,948					3,261						1,938						(5,606)						(2,465)						—						29,076

Nine Months ended September 30, 2024						Beginning Balance						Current Provision for Securities without Prior Allowance						Initial Allowance for Purchased Credit Deteriorated Assets with Credit Deterioration						Increase (Decrease) on Securities with Prior Allowance, excluding intent (or Requirement) to Sell Securities						Reductions for Securities Sold						Reductions for Securities Identified as Intent (or Requirement) to Sell during the Period						Ending Balance
($ in thousands)
Foreign government						$	35					—						—						(4)						(7)						—						24
Obligations of states and political subdivisions						669						118						—						(299)						(16)						—						472
Corporate securities						12,999						1,325						—						(1,282)						(999)						(9)						12,034
CLO and other ABS						2,854						1,886						—						(188)						(90)						—						4,462
RMBS						11,649						—						—						139						(279)						—						11,509
CMBS						6						—						—						(3)						—						—						3
Total AFS fixed income securities						$	28,212					3,329						—						(1,637)						(1,391)						(9)						28,504

Schedule of Quantitative Information about Unrealized Losses on AFS

Quantitative information about unrealized losses on our AFS portfolio follows:

September 30, 2025						Less than 12 months												12 months or longer												Total
($ in thousands)						Fair Value						Unrealized Losses						Fair Value						Unrealized Losses						Fair Value						Unrealized Losses
AFS fixed income securities:
U.S. government and government agencies						$	14,800					(200)						110,360						(15,129)						125,160						(15,329)
Foreign government						—						—						9,040						(829)						9,040						(829)
Obligations of states and political subdivisions						70,170						(1,158)						225,951						(24,428)						296,121						(25,586)
Corporate securities						186,603						(3,200)						841,224						(70,530)						1,027,827						(73,730)
CLO and other ABS						312,803						(6,383)						491,315						(30,606)						804,118						(36,989)
RMBS						284,520						(2,875)						710,469						(65,845)						994,989						(68,720)
CMBS						46,613						(1,476)						326,468						(15,781)						373,081						(17,257)
Total AFS fixed income securities						$	915,509					(15,292)						2,714,827						(223,148)						3,630,336						(238,440)

December 31, 2024						Less than 12 months												12 months or longer												Total
($ in thousands)						Fair Value						Unrealized Losses						Fair Value						Unrealized Losses						Fair Value						Unrealized Losses
AFS fixed income securities:
U.S. government and government agencies						$	14,708					(70)						105,326						(19,683)						120,034						(19,753)
Foreign government						—						—						9,302						(1,333)						9,302						(1,333)
Obligations of states and political subdivisions						153,996						(3,539)						247,735						(28,820)						401,731						(32,359)
Corporate securities						684,999						(11,699)						1,083,392						(111,502)						1,768,391						(123,201)
CLO and other ABS						349,786						(6,296)						601,057						(43,393)						950,843						(49,689)
RMBS						714,061						(21,206)						677,574						(91,516)						1,391,635						(112,722)
CMBS						184,394						(2,870)						417,472						(28,154)						601,866						(31,024)
Total AFS fixed income securities						$	2,101,944					(45,680)						3,141,858						(324,401)						5,243,802						(370,081)

Schedule of Fixed Maturity Securities by Contractual Maturities

AFS and held-to-maturity ("HTM") fixed income securities at September 30, 2025, by contractual maturity are shown below. The maturities of RMBS, CMBS, CLO and other ABS securities were calculated using each security's expected maturities. Expected maturities may differ from contractual maturities because issuers may have the right to call or prepay obligations with or without call or prepayment penalties.

						AFS						HTM
($ in thousands)						Fair Value						Carrying Value						Fair Value
Due in one year or less						$	560,606					68						68
Due after one year through five years						3,627,688						15,840						15,649
Due after five years through 10 years						3,922,594						8,335						8,537
Due after 10 years						1,164,536						—						—
Total fixed income securities						$	9,275,424					24,243						24,254

Schedule of Alternative Investment Portfolio by Strategy and Remaining Commitment Amount and Maximum Exposure to Loss Associated with Each Strategy

The following table summarizes our alternative investment portfolio by strategy:

						September 30, 2025																		December 31, 2024
($ in thousands)						Carrying Value						Remaining Commitment						Maximum Exposure to Loss						Carrying Value						Remaining Commitment						Maximum Exposure to Loss
Alternative Investments
Private equity						$	334,659					161,065						495,724						346,020						182,355						528,375
Private credit						36,928						134,693						171,621						52,100						99,185						151,285
Real assets						45,479						50,352						95,831						42,776						38,950						81,726
Total alternative investments						$	417,066					346,110						763,176						440,896						320,490						761,386

Schedule of Aggregated Summarized Income Statement Financial Information for Partnerships in Alternative Investment Portfolio

The following table shows gross summarized financial information for our alternative investments portfolio, including the portion we do not own. As the majority of these investments report results to us on a one-quarter lag, the summarized financial statement information is for the 3- and 9-month periods ended June 30:

Income Statement Information						Quarter ended September 30,												Nine Months ended September 30,
($ in millions)						2025						2024						2025						2024
Net investment income (loss)						$	(192.1)					230.6						$	460.0					127.0
Realized gains						4,429.6						1,878.3						5,992.2						5,263.4
Net change in unrealized appreciation (depreciation)						(1,919.7)						607.7						935.7						7,277.0
Net income						$	2,317.8					2,716.6						$	7,387.9					12,667.4
Alternative investment income included in "Net investment income earned" on our Consolidated Statements of Income						$	11.8					9.0						$	22.9					26.4

Schedule of Securities Pledged as Collateral

The following table summarizes the market value of these securities at September 30, 2025:

($ in millions)						FHLBI Collateral						FHLBNY Collateral												State and Regulatory Deposits						Total
U.S. government and government agencies						$	—					—												24.5						24.5
Obligations of states and political subdivisions						—						—												1.8						1.8
RMBS						65.4						20.4												0.5						86.3
CMBS						—						6.1												—						6.1
Total pledged as collateral						$	65.4					26.5												26.8						118.7

Schedule of Pre-Tax Net Investment Income Earned

The components of pre-tax net investment income earned were as follows:

						Quarter ended September 30,												Nine Months ended September 30,
($ in thousands)						2025						2024						2025						2024
Fixed income securities						$	117,242					98,464						$	338,057					286,501
CMLs						3,999						3,238						11,375						9,177
Equity securities						5,164						5,362						13,639						12,147
Short-term investments						5,712						6,457						17,212						14,656
Alternative investments						11,769						9,031						22,852						26,429
Other investments						171						251						565						632
Investment expenses						(5,402)						(5,044)						(16,386)						(15,292)
Net investment income earned						$	138,655					117,759						$	387,314					334,250

Schedule of Realized and Unrealized Gains (Losses) on Securities

The following table summarizes net realized and unrealized investment gains and losses for the periods indicated:

						Quarter ended September 30,												Nine Months ended September 30,
($ in thousands)						2025						2024						2025						2024
Gross gains on sales						$	8,311					4,159						$	12,192					10,681
Gross losses on sales						(8,886)						(2,012)						(13,663)						(5,228)
Net realized gains (losses) on disposals						(575)						2,147						(1,471)						5,453
Net unrealized gains (losses) on equity securities						7,802						2,407						12,492						3,006
Net credit loss benefit (expense) on fixed income securities, AFS						829						2,191						2,345						(1,692)
Net credit loss benefit (expense) on CMLs						1						(2)						(149)						134
Losses on securities for which we have the intent to sell						—						(752)						(759)						(1,248)
Other realized gains (losses)						—						(602)						—						(602)
Net realized and unrealized investment gains (losses)						$	8,057					5,389						$	12,458					5,051

Schedule of Unrealized Gain (Loss) on Equity Securities

Net unrealized gains and losses recognized in income on equity securities, as reflected in the table above, included the following:

						Quarter ended September 30,												Nine Months ended September 30,
($ in thousands)						2025						2024						2025						2024
Unrealized gains (losses) recognized in income on equity securities:
On securities remaining in our portfolio at end of period						$	7,802					1,997						$	11,341					4,904
On securities sold in period						—						410						1,151						(1,898)
Total unrealized gains (losses) recognized in income on equity securities						$	7,802					2,407						$	12,492					3,006

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