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Investments (Tables)

12 Months Ended

Dec. 31, 2020

Investment [Line Items]

Schedule of Unrealized Gains (Losses) On Investments

($ in thousands)						2020						2019						2018
AFS securities:
Fixed income securities						$	386,380					215,634						2,302
Total AFS securities						386,380						215,634						2,302
HTM securities:
Fixed income securities						7						31						89
Total HTM securities						7						31						89
Short-term securities						6						23						—
Total net unrealized gains						386,393						215,688						2,391
Deferred income tax						(81,142)						(45,294)						(502)
Net unrealized gains, net of deferred income tax						305,251						170,394						1,889
Cumulative effect adjustment due to accounting change for equity unrealized1						—						—						30,726
Cumulative effect adjustment due to accounting changes for stranded tax assets1						—						—						(17,920)
Increase (decrease) in net unrealized gains in OCI, net of deferred income tax						$	134,857					168,505						(65,881)

Schedule of Available For Sale Securities

December 31, 2020
						Cost/
						Amortized						Allowance for						Unrealized						Unrealized						Fair
($ in thousands)						Cost						Credit Losses						Gains						Losses						Value
AFS fixed income securities:
U.S. government and government agencies						$	110,038					—						6,239						(137)						116,140
Foreign government						16,801						(1)						1,569						(3)						18,366
Obligations of states and political subdivisions						1,159,588						(4)						87,564						(11)						1,247,137
Corporate securities						2,152,203						(2,782)						180,971						(2,340)						2,328,052
CLO and other ABS						1,014,820						(592)						20,166						(7,843)						1,026,551
RMBS						999,485						(561)						53,065						(201)						1,051,788
CMBS						620,582						(29)						48,348						(1,007)						667,894
Total AFS fixed income securities						$	6,073,517					(3,969)						397,922						(11,542)						6,455,928

December 31, 2019
						Cost/
						Amortized						Unrealized						Unrealized						Fair
($ in thousands)						Cost						Gains						Losses						Value
AFS fixed income securities:
U.S. government and government agencies						$	112,680					3,506						—						116,186
Foreign government						18,011						533						(2)						18,542
Obligations of states and political subdivisions						1,168,185						62,175						(270)						1,230,090
Corporate securities						1,866,881						81,906						(1,310)						1,947,477
CLO and other ABS						790,517						7,929						(5,434)						793,012
RMBS						1,409,003						43,421						(455)						1,451,969
CMBS						514,709						23,902						(267)						538,344
Total AFS fixed income securities						$	5,879,986					223,372						(7,738)						6,095,620

Schedule of debt securities, available-for-sale, allowance for credit losses

2020
($ in thousands)			Beginning Balance						Current Provisions for Securities without Prior Allowance						Increase (Decrease) on Securities with Prior Allowance, excluding intent (or Requirements) to Sell Securities						Reductions for Securities Sold						Reductions for Securities Identified as Intent (or Requirement) to Sell during the Period						Ending Balance
Foreign Government			$	—					19						—						(18)						—						1
Obligations of states and political subdivisons			—						4						—						—						—						4
Corporate Securities			—						3,645						—						(781)						(82)						2,782
CLO and other ABS			—						722						—						(113)						(17)						592
RMBS			—						623						—						(62)						—						561
CMBS			—						29						—						—						—						29
Total AFS fixed income securities			$	—					5,042						—						(974)						(99)						3,969

Schedule of Fair Value and Gross Pre-Tax Net Unrealized/Unrecognized Loss of Securities by Length of Time

December 31, 2020						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						$	11,519					(137)						—						—						11,519						(137)
Foreign government						1,122						(3)						—						—						1,122						(3)
Obligations of states and political subdivisions						2,223						(11)						—						—						2,223						(11)
Corporate securities						65,187						(2,152)						2,400						(188)						67,587						(2,340)
CLO and other ABS						261,746						(2,995)						165,661						(4,848)						427,407						(7,843)
RMBS						18,227						(194)						1,181						(7)						19,408						(201)
CMBS						55,482						(616)						16,093						(391)						71,575						(1,007)
Total AFS fixed income securities						$	415,506					(6,108)						185,335						(5,434)						600,841						(11,542)

December 31, 2019						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						$	—					—						—						—						—						—
Foreign government						1,416						(2)						—						—						1,416						(2)
Obligations of states and political subdivisions						35,838						(270)						—						—						35,838						(270)
Corporate securities						84,832						(480)						20,182						(830)						105,014						(1,310)
CLO and other ABS						205,191						(1,938)						204,385						(3,496)						409,576						(5,434)
RMBS						126,089						(425)						5,375						(30)						131,464						(455)
CMBS						62,893						(264)						828						(3)						63,721						(267)
Total AFS fixed income securities						$	516,259					(3,379)						230,770						(4,359)						747,029						(7,738)

Schedule of Investments Classified by Contractual Maturity Date

						AFS						HTM
($ in thousands)						Fair Value						Carrying Value						Fair Value
Due in one year or less						$	433,241					1,132						1,149
Due after one year through five years						3,639,658						15,692						16,852
Due after five years through 10 years						1,910,480						—						—
Due after 10 years						472,549						—						—
Total fixed income securities						$	6,455,928					16,824						18,001

Schedule of Other Investment Portfolio by Strategy and the Remaining Commitment Amount Associated With Each Strategy

Other Investments						December 31, 2020																		December 31, 2019
($ in thousands)						Carrying Value						Remaining Commitment						Maximum Exposure to Loss1						Carrying Value						Remaining Commitment						Maximum Exposure to Loss1
Alternative Investments
Private equity						$	157,276					100,905						258,181						118,352						93,138						211,490
Private credit						54,017						98,330						152,347						42,532						105,340						147,872
Real assets						19,659						16,493						36,152						23,256						20,741						43,997
Total alternative investments						230,952						215,728						446,680						184,140						219,219						403,359
Other securities						35,370						—						35,370						32,667						—						32,667
Total other investments						$	266,322					215,728						482,050						216,807						219,219						436,026

Schedule of Aggregated Summarized Balance Sheet Financial Information For Partnerships In Our Alternative Investment Portfolio

Balance Sheet Information
December 31,
($ in millions)						2020						2019
Investments						$	55,145					43,857
Total assets						58,819						45,432
Total liabilities						6,744						5,670
Total partners’ capital						52,075						39,762

Schedule of Aggregated Summarized Income Statement Financial Information For Partnerships In Our Alternative Investment Portfolio

Income Statement Information
12 months ended September 30,
($ in millions)						2020						2019						2018
Net investment (loss) income						$	(26)					(8)						134
Realized gains						1,452						695						1,981
Net change in unrealized appreciation						4,898						5,543						1,303
Net income before tax						$	6,324					6,230						3,418
Alternative investment income included in "Net investment income earned" on our Consolidated Statements of Income						26.5						17.9						17.6

Schedule Of Securities Pledged As Collateral

($ in millions)						FHLBI Collateral						FHLBNY Collateral						State and Regulatory Deposits						Total
U.S. government and government agencies						$	—					—						20.1						20.1
Obligations of states and political subdivisions						—						—						5.1						5.1
RMBS						125.0						178.1						—						303.1
CMBS						7.0						36.3						—						43.3
Total pledged as collateral						$	132.0					214.4						25.2						371.6

Schedule of Components of Pre-Tax Net Investment Income Earned

($ in thousands)						2020						2019						2018
Fixed income securities						$	203,926					203,255						178,104
CMLs						844						—						—
Equity securities						9,286						6,996						7,764
Short-term investments						1,821						6,653						3,472
Other investments						26,922						18,778						17,799
Investment expenses						(15,692)						(13,139)						(11,803)
Net investment income earned						$	227,107					222,543						195,336

Schedule of realized and unrealized gains (losses) on securities

($ in thousands)						2020						2019						2018
Gross gains on sales						$	18,893					31,910						28,672
Gross losses on sales						(9,745)						(5,195)						(47,647)
Net realized gains (losses) on disposals						9,148						26,715						(18,975)
Net unrealized gains (losses) on equity securities						7,939						(8,649)						(29,369)
Net credit loss (expense) benefit on fixed maturities, AFS						(5,042)
Net credit loss benefit (expense) on fixed maturities, HTM						4
Losses on securities for which we have the intent to sell						(16,266)
Net OTTI losses recognized in earnings												(3,644)						(6,579)
Net realized and unrealized gains (losses)						$	(4,217)					14,422						(54,923)

Unrealized Gain (Loss) on Equity Securities

($ in thousands)						2020						2019						2018
Unrealized gains (losses) recognized in income on equity securities:
On securities remaining in our portfolio at end of period						$	7,936					1,219						(3,098)
On securities sold in period						3						(9,868)						(26,271)
Total unrealized (losses) recognized in income on equity securities						$	7,939					(8,649)						(29,369)

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