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Investments (Tables)

6 Months Ended

Jun. 30, 2025

Investments [Abstract]

Schedule of Available-for-Sale Securities

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

June 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						$	146,074					—						54						(16,687)						129,441
Foreign government						11,520						(21)						35						(1,011)						10,523
Obligations of states and political subdivisions						490,639						(390)						1,271						(32,862)						458,658
Corporate securities						3,356,690						(9,571)						54,889						(87,916)						3,314,092
Collateralized loan obligations ("CLO") and other asset-backed securities ("ABS")						2,294,816						(7,230)						27,345						(38,751)						2,276,180
Residential mortgage-backed securities ("RMBS")						2,029,324						(11,422)						10,438						(84,773)						1,943,567
Commercial mortgage-backed securities ("CMBS")						760,455						(99)						3,936						(20,086)						744,206
Total AFS fixed income securities						$	9,089,518					(28,733)						97,968						(282,086)						8,876,667

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 June 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						$	19					—						—						2						—						—						21
Obligations of states and political subdivisions						419						27						—						(36)						(20)						—						390
Corporate securities						12,616						306						—						(2,979)						(372)						—						9,571
CLO and other ABS						5,499						182						—						1,607						(58)						—						7,230
RMBS						11,342						—						—						185						(105)						—						11,422
CMBS						280						—						—						(181)						—						—						99
Total AFS fixed income securities						$	30,175					515						—						(1,402)						(555)						—						28,733

Quarter ended June 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						$	29					—						—						(3)						—						—						26
Obligations of states and political subdivisions						695						18						—						(74)						—						—						639
Corporate securities						15,442						846						—						(126)						(212)						—						15,950
CLO and other ABS						2,627						271						—						126						(2)						—						3,022
RMBS						11,580						—						—						171						(91)						—						11,660
CMBS						8						—						—						4						—						—						12
Total AFS fixed income securities						$	30,381					1,135						—						98						(305)						—						31,309

Six Months ended June 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					—						—						—						—						—						21
Obligations of states and political subdivisions						570						32						—						(106)						(106)						—						390
Corporate securities						14,924						935						—						(5,142)						(1,146)						—						9,571
CLO and other ABS						4,889						1,652						—						876						(187)						—						7,230
RMBS						11,544						—						—						138						(260)						—						11,422
CMBS						—						99						—						—						—						—						99
Total AFS fixed income securities						$	31,948					2,718						—						(4,234)						(1,699)						—						28,733

Six Months ended June 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					—						—						(3)						(6)						—						26
Obligations of states and political subdivisions						669						37						—						(59)						(8)						—						639
Corporate securities						12,999						2,362						—						1,166						(568)						(9)						15,950
CLO and other ABS						2,854						427						—						(255)						(4)						—						3,022
RMBS						11,649						—						—						202						(191)						—						11,660
CMBS						6						2						—						4						—						—						12
Total AFS fixed income securities						$	28,212					2,828						—						1,055						(777)						(9)						31,309

Schedule of Quantitative Information about Unrealized Losses on AFS

Quantitative information about unrealized losses on our AFS portfolio follows:

June 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						$	6,275					(40)						108,474						(16,647)						114,749						(16,687)
Foreign government						—						—						9,592						(1,011)						9,592						(1,011)
Obligations of states and political subdivisions						155,940						(3,377)						219,996						(29,485)						375,936						(32,862)
Corporate securities						243,575						(3,677)						969,247						(84,239)						1,212,822						(87,916)
CLO and other ABS						330,552						(6,239)						504,728						(32,512)						835,280						(38,751)
RMBS						557,024						(10,152)						647,612						(74,621)						1,204,636						(84,773)
CMBS						58,645						(1,928)						368,295						(18,158)						426,940						(20,086)
Total AFS fixed income securities						$	1,352,011					(25,413)						2,827,944						(256,673)						4,179,955						(282,086)

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 June 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						$	549,570					135						134
Due after one year through five years						3,627,442						16,082						15,985
Due after five years through 10 years						3,664,357						8,335						8,338
Due after 10 years						1,035,298						—						—
Total fixed income securities						$	8,876,667					24,552						24,457

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:

						June 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						$	325,848					170,686						496,534						346,020						182,355						528,375
Private credit						62,133						99,121						161,254						52,100						99,185						151,285
Real assets						47,014						36,270						83,284						42,776						38,950						81,726
Total alternative investments						$	434,995					306,077						741,072						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 6-month periods ended March 31:

Income Statement Information						Quarter ended June 30,												Six Months ended June 30,
($ in millions)						2025						2024						2025						2024
Net investment income (loss)						$	251.4					242.4						$	652.1					(103.6)
Realized gains						950.6						1,554.2						1,562.6						3,385.1
Net change in unrealized appreciation (depreciation)						975.9						2,850.2						2,855.3						6,669.2
Net income						$	2,177.9					4,646.8						$	5,070.0					9,950.7
Alternative investment income included in "Net investment income earned" on our Consolidated Statements of Income						$	4.0					10.5						$	11.1					17.4

Schedule of Securities Pledged as Collateral

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

($ in millions)						FHLBI Collateral						FHLBNY Collateral												State and Regulatory Deposits						Total
U.S. government and government agencies						$	—					—												24.3						24.3
Obligations of states and political subdivisions						—						—												1.8						1.8
RMBS						65.7						20.9												0.5						87.1
CMBS						0.4						7.3												—						7.7
Total pledged as collateral						$	66.1					28.2												26.6						120.9

Schedule of Pre-Tax Net Investment Income Earned

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

						Quarter ended June 30,												Six Months ended June 30,
($ in thousands)						2025						2024						2025						2024
Fixed income securities						$	115,733					93,935						$	220,815					188,037
CMLs						3,761						3,145						7,376						5,939
Equity securities						4,908						1,877						8,475						6,785
Short-term investments						5,267						4,680						11,500						8,199
Alternative investments						4,004						10,517						11,083						17,398
Other investments						163						118						394						381
Investment expenses						(5,868)						(5,630)						(10,984)						(10,248)
Net investment income earned						$	127,968					108,642						$	248,659					216,491

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 June 30,												Six Months ended June 30,
($ in thousands)						2025						2024						2025						2024
Gross gains on sales						$	2,154					4,387						$	3,881					6,522
Gross losses on sales						(2,394)						(1,251)						(4,777)						(3,216)
Net realized gains (losses) on disposals						(240)						3,136						(896)						3,306
Net unrealized gains (losses) on equity securities						3,640						(93)						4,690						599
Net credit loss benefit (expense) on fixed income securities, AFS						887						(1,233)						1,516						(3,883)
Net credit loss benefit (expense) on CMLs						(115)						(32)						(150)						136
Losses on securities for which we have the intent to sell						—						(481)						(759)						(496)
Net realized and unrealized investment gains (losses)						$	4,172					1,297						$	4,401					(338)

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 June 30,												Six Months ended June 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						$	3,018					2,617						$	3,539					2,906
On securities sold in period						622						(2,710)						1,151						(2,307)
Total unrealized gains (losses) recognized in income on equity securities						$	3,640					(93)						$	4,690					599

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