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Investments (Tables)

12 Months Ended

Dec. 31, 2015

Investment [Line Items]

Schedule of Unrealized Gains On Investments

($ in thousands)		2015				2014			2013
AFS securities:
Fixed income securities		$	55,689			90,336			39,559
Equity securities		13,235				32,389			37,421
Total AFS securities		68,924				122,725			76,980
HTM securities:
Fixed income securities		300				958			2,257
Total HTM securities		300				958			2,257
Total net unrealized gains		69,224				123,683			79,237
Deferred income tax expense		(24,228		)		(43,289	)		(27,733	)
Net unrealized gains, net of deferred income tax		44,996				80,394			51,504
(Decrease) increase in net unrealized gains in OCI, net of deferred income tax		$	(35,398	)		28,890			(70,824	)

Schedule of Held-to-maturity Securities

December 31, 2015						Net
						Unrealized						Unrecognized			Unrecognized
		Amortized				Gains			Carrying			Holding			Holding			Fair
($ in thousands)		Cost				(Losses)			Value			Gains			Losses			Value
Obligations of state and political subdivisions		$	175,269			848			176,117			5,763			—			181,880
Corporate securities		20,228				(185	)		20,043			1,972			—			22,015
ABS		1,030				(120	)		910			118			—			1,028
CMBS		4,527				(243	)		4,284			337			—			4,621
Total HTM fixed income securities		$	201,054			300			201,354			8,190			—			209,544

December 31, 2014						Net
						Unrealized						Unrecognized			Unrecognized
		Amortized				Gains			Carrying			Holding			Holding			Fair
($ in thousands)		Cost				(Losses)			Value			Gains			Losses			Value
Foreign government		$	5,292			47			5,339			55			—			5,394
Obligations of state and political subdivisions		285,301				2,071			287,372			11,760			—			299,132
Corporate securities		18,899				(273	)		18,626			2,796			—			21,422
ABS		2,818				(455	)		2,363			460			—			2,823
CMBS		4,869				(432	)		4,437			753			—			5,190
Total HTM fixed income securities		$	317,179			958			318,137			15,824			—			333,961

Schedule of Available For Sale Securities

December 31, 2015
		Cost/
		Amortized				Unrealized			Unrealized			Fair
($ in thousands)		Cost				Gains			Losses			Value
AFS fixed income securities:
U.S. government and government agencies		$	99,485			4,721			(91	)		104,115
Foreign government		14,885				298			(2	)		15,181
Obligations of states and political subdivisions		1,314,779				44,523			(160	)		1,359,142
Corporate securities		1,892,296				23,407			(15,521	)		1,900,182
ABS		244,541				531			(918	)		244,154
CMBS1		245,252				750			(2,410	)		243,592
RMBS2		541,276				4,274			(3,713	)		541,837
Total AFS fixed income securities		4,352,514				78,504			(22,815	)		4,408,203
AFS equity securities:
Common stock		181,991				14,796			(1,998	)		194,789
Preferred stock		11,825				477			(40	)		12,262
Total AFS equity securities		193,816				15,273			(2,038	)		207,051
Total AFS securities		$	4,546,330			93,777			(24,853	)		4,615,254

December 31, 2014
		Cost/
		Amortized				Unrealized			Unrealized			Fair
($ in thousands)		Cost				Gains			Losses			Value
AFS fixed income securities:
U.S. government and government agencies		$	116,666			7,592			(128	)		124,130
Foreign government		27,035				796			—			27,831
Obligations of states and political subdivisions		1,208,776				38,217			(729	)		1,246,264
Corporate securities		1,763,427				42,188			(5,809	)		1,799,806
ABS		176,837				760			(373	)		177,224
CMBS1		177,932				2,438			(777	)		179,593
RMBS2		505,113				8,587			(2,426	)		511,274
Total AFS fixed income securities		3,975,786				100,578			(10,242	)		4,066,122
AFS equity securities:
Common stock		159,011				32,721			(332	)		191,400
Total AFS equity securities		159,011				32,721			(332	)		191,400
Total AFS securities		$	4,134,797			133,299			(10,574	)		4,257,522

¹ CMBS includes government guaranteed agency securities with a fair value of $4.5 million at December 31, 2015 and $13.2 million at December 31, 2014.

² RMBS includes government guaranteed agency securities with a fair value of $19.7 million at December 31, 2015 and $32.4 million at December 31, 2014.

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

December 31, 2015		Less than 12 months							12 months or longer
($ in thousands)		Fair  Value				Unrealized Losses1			Fair Value			Unrealized Losses1
AFS fixed income securities:
U.S. government and government agencies		$	16,006			(87	)		396			(4	)
Foreign government		1,067				(2	)		—			—
Obligations of states and political subdivisions		28,617				(160	)		—			—
Corporate securities		761,479				(12,671	)		50,382			(2,850	)
ABS		197,477				(807	)		12,022			(111	)
CMBS		146,944				(2,196	)		15,385			(214	)
RMBS		264,914				(1,992	)		63,395			(1,721	)
Total AFS fixed income securities		1,416,504				(17,915	)		141,580			(4,900	)
AFS equity securities:
Common stock		31,148				(1,998	)		—			—
Preferred stock		1,531				(40	)		—			—
Total AFS equity securities		32,679				(2,038	)		—			—
Subtotal		$	1,449,183			(19,953	)		141,580			(4,900	)

		Less than 12 months										12 months or longer
($ in thousands)		Fair Value				Unrealized Losses1			Unrecognized Gains2			Fair Value			Unrealized Losses1			Unrecognized Gains2
HTM securities:
ABS		$	—			—			—			805			(122	)		116
Subtotal		—				—			—			805			(122	)		116
Total AFS and HTM		$	1,449,183			(19,953	)		—			142,385			(5,022	)		116

December 31, 2014		Less than 12 months							12 months or longer
($ in thousands)		Fair  Value				Unrealized Losses1			Fair Value			Unrealized Losses1
AFS fixed income securities:
U.S. government and government agencies		$	7,567			(13	)		10,866			(115	)
Obligations of states and political subdivisions		47,510				(105	)		64,018			(624	)
Corporate securities		276,648				(1,734	)		153,613			(4,075	)
ABS		113,202				(178	)		15,618			(195	)
CMBS		12,799				(34	)		59,219			(743	)
RMBS		3,399				(8	)		138,724			(2,418	)
Total AFS fixed income securities		461,125				(2,072	)		442,058			(8,170	)
AFS equity securities:
Common stock		5,262				(336	)		—			—
Total AFS equity securities		5,262				(336	)		—			—
Subtotal		$	466,387			(2,408	)		442,058			(8,170	)

		Less than 12 months										12 months or longer
($ in thousands)		Fair Value				Unrealized Losses1			Unrecognized Gains2			Fair Value			Unrealized Losses1			Unrecognized Gains2
HTM securities:
Obligations of states and political subdivisions		$	196			(3	)		1			—			—			—
ABS		—				—			—			2,235			(455	)		439
Subtotal		196				(3	)		1			2,235			(455	)		439
Total AFS and HTM		$	466,583			(2,411	)		1			444,293			(8,625	)		439

¹ Gross unrealized losses include non-OTTI unrealized amounts and OTTI losses recognized in AOCI. In addition, this column includes remaining unrealized gain or loss amounts on securities that were transferred to an HTM designation in the first quarter of 2009 for those securities that are in a net unrealized/unrecognized loss position.

² Unrecognized holding gains represent fair value fluctuations from the later of: (i) the date a security is designated as HTM; or (ii) the date that an OTTI charge is recognized on an HTM security.

Schedule of the Number of Securities in an Unrealized Unrecognized Loss Position

($ in thousands)
December 31, 2015									December 31, 2014
Number of Issues			% of  Market/Book		Unrealized/Unrecognized Loss				Number of Issues			% of Market/Book		Unrealized/ Unrecognized Loss
606			80% - 99%		$	22,971			350			80% - 99%		$	10,596
3			60% - 79%		1,888				—			60% - 79%		—
—			40% - 59%		—				—			40% - 59%		—
—			20% - 39%		—				—			20% - 39%		—
—			0% - 19%		—				—			0% - 19%		—
					$	24,859								$	10,596

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

Other Investments		Carrying Value							2015
		December 31,				December 31,			Remaining
($ in thousands)		2015				2014			Commitment
Alternative Investments
Private equity		$	35,088			48,538			30,204
Private credit		13,246				18,533			15,129
Real assets		19,500				25,897			25,820
Total alternative investments		67,834				92,968			71,153
Other securities		10,008				6,235			3,200
Total other investments		$	77,842			99,203			74,353

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

Balance Sheet Information
September 30,
($ in millions)		2015				2014
Investments		$	7,527			10,096
Total assets		8,515				10,695
Total liabilities		316				545
Total partners’ capital		8,199				10,150

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

Income Statement Information
12 months ended September 30,
($ in millions)		2015				2014			2013
Net investment income		$	129			226			406
Realized gains		1,187				581			913
Net change in unrealized (depreciation) appreciation		(1,364		)		1,098			382
Net income		$	(48	)		1,905			1,701
Insurance Subsidiaries' other investments income		(1.9		)		13.6			15.2

Schedule Of Securities Pledged As Collateral

The following table summarizes the market value of these securities at December 31, 2015:

($ in millions)		FHLBI Collateral				Reinsurance Collateral			State and Regulatory Deposits			Total
U.S. government and government agencies		$	7.5			—			24.0			31.5
Obligations of states and political subdivisions		—				5.0			—			5.0
Corporate securities		—				4.7			—			4.7
CMBS		1.2				—			—			1.2
RMBS		55.0				1.8			—			56.8
Total pledged as collateral		$	63.7			11.5			24.0			99.2

Schedule of Components of Net Investment Income Earned

($ in thousands)		2015				2014			2013
Fixed income securities		$	123,230			126,489			121,582
Equity securities, dividend income		9,161				7,449			6,140
Short-term investments		112				66			117
Other investments		(1,890		)		13,580			15,208
Investment expenses		(9,297		)		(8,876	)		(8,404	)
Net investment income earned		$	121,316			138,708			134,643

Schedule of OTTI by Asset Type

2015									Recognized in
($ in thousands)		Gross				Included in OCI			Earnings
AFS fixed income securities:
Corporate securities		$	2,188			—			2,188
RMBS		1				—			1
Total AFS fixed income securities		2,189				—			2,189
AFS equity securities:
Common stock		15,996				—			15,996
Preferred stock		181				—			181
Total AFS equity securities		16,177				—			16,177
Total OTTI losses		$	18,366			—			18,366

2014									Recognized in
($ in thousands)		Gross				Included in OCI			Earnings
AFS fixed income securities:
RMBS		$	7			—			7
Total AFS fixed income securities		7				—			7
AFS equity securities:
Common stock		10,517				—			10,517
Total AFS equity securities		10,517				—			10,517
Other investments		580				—			580
Total OTTI losses		$	11,104			—			11,104

2013									Recognized in
($ in thousands)		Gross				Included in OCI			Earnings
HTM fixed income securities:
ABS		$	(44	)		(47	)		3
Total HTM fixed income securities		(44		)		(47	)		3
AFS fixed income securities:
RMBS		16				(30	)		46
Total AFS fixed income securities		16				(30	)		46
AFS equity securities:
Common stock		3,747				—			3,747
Total AFS equity securities		3,747				—			3,747
Other investments		1,847				—			1,847
Total OTTI losses		$	5,566			(77	)		5,643

Schedule of Gross Credit Loss Impairments on Fixed Maturity Securities for Which a Portion of the OTTI Charge Was Recognized In OCI

Schedule of Components of Net Realized Gains Excluding OTTI Charges

($ in thousands)		2015				2014			2013
HTM fixed income securities
Gains		$	5			2			195
Losses		(1		)		(20	)		(95	)
AFS fixed income securities
Gains		4,515				1,945			3,340
Losses		(312		)		(392	)		(373	)
AFS equity securities
Gains		29,168				36,871			24,776
Losses		(1,347		)		(704	)		(408	)
Other investments
Gains		162				1			—
Losses		(653		)		—			(1,060	)
Total other net realized investment gains		$	31,537			37,703			26,375

Held-to-maturity Securities [Member]

Investment [Line Items]

Schedule Of Fixed Maturity Securities By Contractual Maturities

($ in thousands)		Carrying Value				Fair Value
Due in one year or less		$	98,601			99,872
Due after one year through five years		89,231				94,358
Due after five years through 10 years		13,522				15,314
Total HTM fixed income securities		$	201,354			209,544

AFS Fixed Income Securities [Member]

Investment [Line Items]

Schedule Of Fixed Maturity Securities By Contractual Maturities

($ in thousands)		Fair Value
Due in one year or less		$	472,331
Due after one year through five years		2,135,301
Due after five years through 10 years		1,733,858
Due after 10 years		66,713
Total AFS fixed income securities		$	4,408,203

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