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Investments (Tables) | 12 Months Ended
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Dec. 31, 2014
Investment [Line Items] |
Schedule of Unrealized Gains On Investments |
($ in thousands) |  | 2014 |  | 2013 |  | 2012
AFS securities: |  |  |  |  |  |  |  |  |
Fixed income securities |  | $ | 90,336 |  |  | 39,559 |  |  | 165,330 |
Equity securities |  | 32,389 |  |  | 37,421 |  |  | 18,941 |
Total AFS securities |  | 122,725 |  |  | 76,980 |  |  | 184,271 |
HTM securities: |  |  |  |  |  |  |  |  |
Fixed income securities |  | 958 |  |  | 2,257 |  |  | 3,926 |
Total HTM securities |  | 958 |  |  | 2,257 |  |  | 3,926 |
Total net unrealized gains |  | 123,683 |  |  | 79,237 |  |  | 188,197 |
Deferred income tax expense |  | (43,289 | ) |  | (27,733 | ) |  | (65,869 | )
Net unrealized gains, net of deferred income tax |  | 80,394 |  |  | 51,504 |  |  | 122,328 |
Increase (decrease) in net unrealized gains in OCI, net of deferred income tax |  | $ | 28,890 |  |  | (70,824 | ) |  | 25,080 |
Schedule of Held-to-maturity Securities |
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 |
December 31, 2013 |  |  |  | Net |  |  |  |  |  |  |  |
|  |  |  | Unrealized |  |  |  | Unrecognized |  | Unrecognized |  |
|  | Amortized |  | Gains |  | Carrying |  | Holding |  | Holding |  | Fair
($ in thousands) |  | Cost |  | (Losses) |  | Value |  | Gains |  | Losses |  | Value
Foreign government |  | $ | 5,292 |  |  | 131 |  |  | 5,423 |  |  | 168 |  |  | — |  |  | 5,591 |
Obligations of state and political subdivisions |  | 348,109 |  |  | 4,013 |  |  | 352,122 |  |  | 17,634 |  |  | — |  |  | 369,756 |
Corporate securities |  | 28,174 |  |  | (346 | ) |  | 27,828 |  |  | 2,446 |  |  | — |  |  | 30,274 |
ABS |  | 3,413 |  |  | (655 | ) |  | 2,758 |  |  | 657 |  |  | — |  |  | 3,415 |
CMBS |  | 5,634 |  |  | (886 | ) |  | 4,748 |  |  | 3,197 |  |  | — |  |  | 7,945 |
Total HTM fixed income securities |  | $ | 390,622 |  |  | 2,257 |  |  | 392,879 |  |  | 24,102 |  |  | — |  |  | 416,981 |
Schedule of Available For Sale Securities |
December 31, 2014 |  |  |  |  |  |  |  |
|  | Cost/ |  |  |  |  |  |
|  | Amortized |  | Unrealized |  | Unrealized |  | Fair
($ in thousands) |  | Cost |  | Gains |  | Losses |  | Value
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 |
CMBS 1 |  | 177,932 |  |  | 2,438 |  |  | (777 | ) |  | 179,593 |
RMBS 2 |  | 505,113 |  |  | 8,587 |  |  | (2,426 | ) |  | 511,274 |
AFS fixed income securities |  | 3,975,786 |  |  | 100,578 |  |  | (10,242 | ) |  | 4,066,122 |
AFS equity securities |  | 159,011 |  |  | 32,721 |  |  | (332 | ) |  | 191,400 |
Total AFS securities |  | $ | 4,134,797 |  |  | 133,299 |  |  | (10,574 | ) |  | 4,257,522 |
December 31, 2013 |  |  |  |  |  |  |  |
|  | Cost/ |  |  |  |  |  |
|  | Amortized |  | Unrealized |  | Unrealized |  | Fair
($ in thousands) |  | Cost |  | Gains |  | Losses |  | Value
U.S. government and government agencies |  | $ | 163,218 |  |  | 10,661 |  |  | (504 | ) |  | 173,375 |
Foreign government |  | 29,781 |  |  | 906 |  |  | (72 | ) |  | 30,615 |
Obligations of states and political subdivisions |  | 946,455 |  |  | 25,194 |  |  | (20,025 | ) |  | 951,624 |
Corporate securities |  | 1,707,928 |  |  | 44,004 |  |  | (17,049 | ) |  | 1,734,883 |
ABS |  | 140,430 |  |  | 934 |  |  | (468 | ) |  | 140,896 |
CMBS 1 |  | 172,288 |  |  | 2,462 |  |  | (3,466 | ) |  | 171,284 |
RMBS 2 |  | 515,877 |  |  | 7,273 |  |  | (10,291 | ) |  | 512,859 |
AFS fixed income securities |  | 3,675,977 |  |  | 91,434 |  |  | (51,875 | ) |  | 3,715,536 |
AFS equity securities |  | 155,350 |  |  | 37,517 |  |  | (96 | ) |  | 192,771 |
Total AFS securities |  | $ | 3,831,327 |  |  | 128,951 |  |  | (51,971 | ) |  | 3,908,307 |
1 CMBS includes government guaranteed agency securities with a fair value of $13.2 million at December 31, 2014 and $30.0 million at December 31, 2013. 2 RMBS includes government guaranteed agency securities with a fair value of $32.4 million at December 31, 2014 and $55.2 million at December 31, 2013.
Schedule of Fair Value and Gross Pre-Tax Net Unrealized/Unrecognized Loss of Securities by Length of Time |
December 31, 2014 |  | Less than 12 months |  | 12 months or longer
($ in thousands) |  | Fair Value |  | Unrealized Losses 1 |  | Fair Value |  | Unrealized Losses 1
AFS 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 fixed income securities |  | 461,125 |  |  | (2,072 | ) |  | 442,058 |  |  | (8,170 | )
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 Losses 1 |  | Unrecognized Gains 2 |  | Fair Value |  | Unrealized Losses 1 |  | Unrecognized Gains 2
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 |
December 31, 2013 |  | Less than 12 months |  | 12 months or longer
($ in thousands) |  | Fair Value |  | Unrealized Losses 1 |  | Fair Value |  | Unrealized Losses 1
AFS securities: |  |  |  |  |  |  |  |  |  |  |  |
U.S. government and government agencies |  | $ | 16,955 |  |  | (500 | ) |  | 507 |  |  | (4 | )
Foreign government |  | 2,029 |  |  | (30 | ) |  | 2,955 |  |  | (42 | )
Obligations of states and political subdivisions |  | 442,531 |  |  | (19,120 | ) |  | 13,530 |  |  | (905 | )
Corporate securities |  | 511,100 |  |  | (15,911 | ) |  | 14,771 |  |  | (1,138 | )
ABS |  | 68,725 |  |  | (468 | ) |  | — |  |  | — |
CMBS |  | 100,396 |  |  | (2,950 | ) |  | 6,298 |  |  | (516 | )
RMBS |  | 268,943 |  |  | (10,031 | ) |  | 2,670 |  |  | (260 | )
Total fixed income securities |  | 1,410,679 |  |  | (49,010 | ) |  | 40,731 |  |  | (2,865 | )
Equity securities |  | 1,124 |  |  | (96 | ) |  | — |  |  | — |
Subtotal |  | $ | 1,411,803 |  |  | (49,106 | ) |  | 40,731 |  |  | (2,865 | )
|  | Less than 12 months |  | 12 months or longer
($ in thousands) |  | Fair Value |  | Unrealized Losses 1 |  | Unrecognized Gains 2 |  | Fair Value |  | Unrealized Losses 1 |  | Unrecognized Gains 2
HTM securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Obligations of states and political subdivisions |  | $ | 65 |  |  | (5 | ) |  | 5 |  |  | 441 |  |  | (20 | ) |  | 14 |
ABS |  | — |  |  | — |  |  | — |  |  | 2,490 |  |  | (655 | ) |  | 621 |
Subtotal |  | $ | 65 |  |  | (5 | ) |  | 5 |  |  | 2,931 |  |  | (675 | ) |  | 635 |
Total AFS and HTM |  | $ | 1,411,868 |  |  | (49,111 | ) |  | 5 |  |  | 43,662 |  |  | (3,540 | ) |  | 635 |
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, 2014 |  | December 31, 2013
Number of Issues |  | % of Market/Book |  | Unrealized/Unrecognized Loss |  | Number of Issues |  | % of Market/Book |  | Unrealized/ Unrecognized Loss
350 |  |  | 80% - 99% |  | $ | 10,596 |  |  | 556 |  |  | 80% - 99% |  | $ | 51,835 |
— |  |  | 60% - 79% |  | — |  |  | 1 |  |  | 60% - 79% |  | 176 |
— |  |  | 40% - 59% |  | — |  |  | — |  |  | 40% - 59% |  | — |
— |  |  | 20% - 39% |  | — |  |  | — |  |  | 20% - 39% |  | — |
— |  |  | 0% - 19% |  | — |  |  | — |  |  | 0% - 19% |  | — |
|  |  |  |  | $ | 10,596 |  |  |  |  |  |  |  | $ | 52,011 |
Schedule of Other Investment Portfolio by Strategy and the Remaining Commitment Amount Associated With Each Strategy |
Other Investments |  | Carrying Value |  | 2014
|  | December 31, |  | December 31, |  | Remaining
($ in thousands) |  | 2014 |  | 2013 |  | Commitment
Alternative Investments |  |  |  |  |  |  |  |  |
Secondary private equity |  | $ | 21,807 |  |  | 25,618 |  |  | 7,001 |
Private equity |  | 20,126 |  |  | 20,192 |  |  | 8,890 |
Energy/power generation |  | 14,445 |  |  | 17,361 |  |  | 21,905 |
Real estate |  | 11,452 |  |  | 11,698 |  |  | 10,051 |
Mezzanine financing |  | 9,853 |  |  | 12,738 |  |  | 13,541 |
Distressed debt |  | 8,679 |  |  | 11,579 |  |  | 2,982 |
Venture capital |  | 6,606 |  |  | 7,025 |  |  | 350 |
Total alternative investments |  | 92,968 |  |  | 106,211 |  |  | 64,720 |
Other securities |  | 6,235 |  |  | 1,664 |  |  | 3,711 |
Total other investments |  | $ | 99,203 |  |  | 107,875 |  |  | 68,431 |
Schedule of Aggregated Summarized Balance Sheet Financial Information For Partnerhips In Our Alternative Investment Portfolio |
Balance Sheet Information |  |  |  |
September 30, |  |  |  |
($ in millions) |  | 2014 |  | 2013
Investments |  | $ | 10,096 |  |  | 11,020 |
Total assets |  | 10,695 |  |  | 11,727 |
Total liabilities |  | 545 |  |  | 573 |
Partners’ capital |  | 10,150 |  |  | 11,154 |
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) |  | 2014 |  | 2013 |  | 2012
Net investment income |  | $ | 226 |  |  | 406 |  |  | 226 |
Realized gains |  | 581 |  |  | 913 |  |  | 1,015 |
Net change in unrealized appreciation (depreciation) |  | 1,098 |  |  | 382 |  |  | (100 | )
Net income |  | $ | 1,905 |  |  | 1,701 |  |  | 1,141 |
Insurance Subsidiaries' other investments income |  | 13.6 |  |  | 15.2 |  |  | 9.0 |
Schedule Of Securities Pledged As Collateral | The following table summarizes the market value of these securities at December 31, 2014:
($ in millions) |  | FHLBI Collateral |  | Reinsurance Collateral |  | State and Regulatory Deposits |  | Total
U.S. government and government agencies |  | $ | 7.7 |  |  | — |  |  | 25.3 |  |  | 33.0 |
Obligations of states and political subdivisions |  | — |  |  | 5.7 |  |  | — |  |  | 5.7 |
Corporate securities |  | — |  |  | 5.3 |  |  | — |  |  | 5.3 |
ABS |  | — |  |  | 1.1 |  |  | — |  |  | 1.1 |
CMBS |  | 2.2 |  |  | — |  |  | — |  |  | 2.2 |
RMBS |  | 50.8 |  |  | 2.3 |  |  | — |  |  | 53.1 |
Total pledged as collateral |  | $ | 60.7 |  |  | 14.4 |  |  | 25.3 |  |  | 100.4 |
Schedule of Components of Net Investment Income Earned |
($ in thousands) |  | 2014 |  | 2013 |  | 2012
Fixed income securities |  | $ | 126,489 |  |  | 121,582 |  |  | 124,687 |
Equity securities, dividend income |  | 7,449 |  |  | 6,140 |  |  | 6,215 |
Short-term investments |  | 66 |  |  | 117 |  |  | 151 |
Other investments |  | 13,580 |  |  | 15,208 |  |  | 8,996 |
Investment expenses |  | (8,876 | ) |  | (8,404 | ) |  | (8,172 | )
Net investment income earned |  | $ | 138,708 |  |  | 134,643 |  |  | 131,877 |
Schedule of OTTI by Asset Type |
2014 |  |  |  |  |  | Recognized in
($ in thousands) |  | Gross |  | Included in OCI |  | Earnings
AFS fixed income securities: |  |  |  |  |  |
RMBS |  | $ | 7 |  |  | — |  |  | 7 |
Total AFS fixed income securities |  | 7 |  |  | — |  |  | 7 |
Equity securities |  | 10,517 |  |  | — |  |  | 10,517 |
Total AFS securities |  | 10,524 |  |  | — |  |  | 10,524 |
Other investments |  | 580 |  |  | — |  |  | 580 |
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 |
Equity securities |  | 3,747 |  |  | — |  |  | 3,747 |
Total AFS securities |  | 3,763 |  |  | (30 | ) |  | 3,793 |
Other investments |  | 1,847 |  |  | — |  |  | 1,847 |
OTTI losses |  | $ | 5,566 |  |  | (77 | ) |  | 5,643 |
2012 |  |  |  |  |  | Recognized in
($ in thousands) |  | Gross |  | Included in OCI |  | Earnings
AFS fixed income securities: |  |  |  |  |  |  |  |  |
ABS |  | $ | 98 |  |  | — |  |  | 98 |
CMBS |  | (1,525 | ) |  | (2,335 | ) |  | 810 |
RMBS |  | (35 | ) |  | (218 | ) |  | 183 |
Total AFS fixed income securities |  | (1,462 | ) |  | (2,553 | ) |  | 1,091 |
Equity securities |  | 3,173 |  |  | — |  |  | 3,173 |
OTTI losses |  | $ | 1,711 |  |  | (2,553 | ) |  | 4,264 |
Schedule of Gross Credit Loss Impairments on Fixed Maturity Securities for Which a Portion of the OTTI Charge Was Recognized In OCI |
($ in thousands) |  | 2014 |  | 2013 |  | 2012
Balance, beginning of year |  | $ | 7,488 |  |  | 7,477 |  |  | 6,602 |
Addition for the amount related to credit loss for which an OTTI was not previously recognized |  | — |  |  | — |  |  | — |
Reductions for securities sold during the period |  | (2,044 | ) |  | — |  |  | — |
Reductions for securities for which the amount previously recognized in OCI was recognized in earnings because of intention or potential requirement to sell before recovery of amortized cost |  | — |  |  | — |  |  | — |
Reductions for securities for which the entire amount previously recognized in OCI was recognized in earnings due to a decrease in cash flows expected |  | — |  |  | — |  |  | — |
Additional increases to the amount related to credit loss for which an OTTI was previously recognized |  | — |  |  | 11 |  |  | 875 |
Accretion of credit loss impairments previously recognized due to an increase in cash flows expected to be collected |  | — |  |  | — |  |  | — |
Balance, end of year |  | $ | 5,444 |  |  | 7,488 |  |  | 7,477 |
Schedule of Components of Net Realized Gains Excluding OTTI Charges |
($ in thousands) |  | 2014 |  | 2013 |  | 2012
HTM fixed income securities |  |  |  |  |  |  |  |  |
Gains |  | $ | 2 |  |  | 195 |  |  | 194 |
Losses |  | (20 | ) |  | (95 | ) |  | (217 | )
AFS fixed income securities |  |  |  |  |  |  |  |  |
Gains |  | 1,945 |  |  | 3,340 |  |  | 4,452 |
Losses |  | (392 | ) |  | (373 | ) |  | (472 | )
AFS equity securities |  |  |  |  |  |  |  |  |
Gains |  | 36,871 |  |  | 24,776 |  |  | 10,901 |
Losses |  | (704 | ) |  | (408 | ) |  | (1,205 | )
Short-term investments |  |  |  |  |  |
Losses |  | — |  |  | — |  |  | (2 | )
Other investments |  |  |  |  |  |  |  |  |
Gains |  | 1 |  |  | — |  |  | 1 |
Losses |  | — |  |  | (1,060 | ) |  | (400 | )
Total other net realized investment gains |  | $ | 37,703 |  |  | 26,375 |  |  | 13,252 |
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 |  | $ | 113,266 |  |  | 114,795 |
Due after one year through five years |  | 193,983 |  |  | 206,188 |
Due after five years through 10 years |  | 10,888 |  |  | 12,978 |
Total HTM fixed income securities |  | $ | 318,137 |  |  | $ | 333,961 |
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 |  | $ | 435,190 |
Due after one year through five years |  | 1,961,179 |
Due after five years through 10 years |  | 1,593,287 |
Due after 10 years |  | 76,466 |
Total AFS fixed income securities |  | $ | 4,066,122 |

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