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Investments (Tables) | 9 Months Ended
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Sep. 30, 2015
Investments [Line Items] |
Schedule of Held-to-maturity Securities |
September 30, 2015 |  |  |  |  |  |  |  |  |  |  |  |
($ in thousands) |  | Amortized Cost |  | Net Unrealized Gains (Losses) |  | Carrying Value |  | Unrecognized Holding Gains |  | Unrecognized Holding Losses |  | Fair Value
Obligations of states and political subdivisions |  | $ | 205,443 |  |  | 1,108 |  |  | 206,551 |  |  | 7,423 |  |  | — |  |  | 213,974 |
Corporate securities |  | 18,147 |  |  | (241 | ) |  | 17,906 |  |  | 2,467 |  |  | — |  |  | 20,373 |
Asset-backed securities (“ABS”) |  | 1,209 |  |  | (157 | ) |  | 1,052 |  |  | 158 |  |  | — |  |  | 1,210 |
Commercial mortgage-backed securities (“CMBS”) |  | 4,656 |  |  | (296 | ) |  | 4,360 |  |  | 471 |  |  | — |  |  | 4,831 |
Total HTM fixed income securities |  | $ | 229,455 |  |  | 414 |  |  | 229,869 |  |  | 10,519 |  |  | — |  |  | 240,388 |
December 31, 2014 |  |  |  |  |  |  |  |  |  |  |  |
($ in thousands) |  | Amortized Cost |  | Net Unrealized Gains (Losses) |  | Carrying Value |  | Unrecognized Holding Gains |  | Unrecognized Holding Losses |  | Fair Value
Foreign government |  | $ | 5,292 |  |  | 47 |  |  | 5,339 |  |  | 55 |  |  | — |  |  | 5,394 |
Obligations of states 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 |
September 30, 2015 |  |  |  |  |  |  |  |
($ in thousands) |  | Cost/ Amortized Cost |  | Unrealized Gains |  | Unrealized Losses |  | Fair Value
AFS fixed income securities: |  |  |  |  |  |  |  |
U.S. government and government agencies |  | $ | 109,062 |  |  | 6,069 |  |  | (1 | ) |  | 115,130 |
Foreign government |  | 19,030 |  |  | 657 |  |  | — |  |  | 19,687 |
Obligations of states and political subdivisions |  | 1,303,188 |  |  | 35,552 |  |  | (545 | ) |  | 1,338,195 |
Corporate securities |  | 1,859,834 |  |  | 35,222 |  |  | (8,882 | ) |  | 1,886,174 |
ABS |  | 255,716 |  |  | 1,312 |  |  | (105 | ) |  | 256,923 |
CMBS 1 |  | 220,009 |  |  | 2,450 |  |  | (457 | ) |  | 222,002 |
Residential mortgage-backed securities (“RMBS”)2 |  | 506,932 |  |  | 7,400 |  |  | (1,397 | ) |  | 512,935 |
Total AFS fixed income securities |  | 4,273,771 |  |  | 88,662 |  |  | (11,387 | ) |  | 4,351,046 |
AFS equity securities: |  |  |  |  |  |  |  |
Common stock |  | 208,995 |  |  | 13,542 |  |  | (12,340 | ) |  | 210,197 |
Preferred stock |  | 11,825 |  |  | 46 |  |  | (117 | ) |  | 11,754 |
Total AFS equity securities |  | 220,820 |  |  | 13,588 |  |  | (12,457 | ) |  | 221,951 |
Total AFS securities |  | $ | 4,494,591 |  |  | 102,250 |  |  | (23,844 | ) |  | 4,572,997 |
December 31, 2014 |  |  |  |  |  |  |  |
($ in thousands) |  | Cost/ Amortized Cost |  | Unrealized Gains |  | Unrealized Losses |  | Fair 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 |
CMBS 1 |  | 177,932 |  |  | 2,438 |  |  | (777 | ) |  | 179,593 |
RMBS 2 |  | 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 |  |  | 32,725 |  |  | (336 | ) |  | 191,400 |
Total AFS equity securities |  | 159,011 |  |  | 32,725 |  |  | (336 | ) |  | 191,400 |
Total AFS securities |  | $ | 4,134,797 |  |  | 133,303 |  |  | (10,578 | ) |  | 4,257,522 |
1 CMBS includes government guaranteed agency securities with a fair value of $7.4 million at September 30, 2015 and $13.2 million at December 31, 2014. 2 RMBS includes government guaranteed agency securities with a fair value of $22.5 million at September 30, 2015 and $32.4 million at December 31, 2014.
Schedule of Fair Value and Gross Pre-Tax Net Unrealized/Unrecognized Loss of Securities by Length of Time |
September 30, 2015 |  | Less than 12 months |  | 12 months or longer
($ in thousands) |  | Fair Value |  | Unrealized Losses 1 |  | Fair Value |  | Unrealized Losses 1
AFS fixed income securities: |  |  |  |  |  |  |  |  |  |  |  |
U.S. government and government agencies |  | $ | — |  |  | — |  |  | 399 |  |  | (1 | )
Obligations of states and political subdivisions |  | 96,861 |  |  | (545 | ) |  | — |  |  | — |
Corporate securities |  | 430,481 |  |  | (7,187 | ) |  | 50,552 |  |  | (1,695 | )
ABS |  | 55,856 |  |  | (71 | ) |  | 12,530 |  |  | (34 | )
CMBS |  | 59,004 |  |  | (367 | ) |  | 15,561 |  |  | (90 | )
RMBS |  | 95,254 |  |  | (457 | ) |  | 65,417 |  |  | (940 | )
Total AFS fixed income securities |  | 737,456 |  |  | (8,627 | ) |  | 144,459 |  |  | (2,760 | )
AFS equity securities: |  |  |  |  |  |  |  |
Common stock |  | 133,601 |  |  | (12,340 | ) |  | — |  |  | — |
Preferred stock |  | 8,562 |  |  | (117 | ) |  | — |  |  | — |
Total AFS equity securities |  | 142,163 |  |  | (12,457 | ) |  | — |  |  | — |
Subtotal |  | $ | 879,619 |  |  | (21,084 | ) |  | 144,459 |  |  | (2,760 | )
|  | 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: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
ABS |  | $ | — |  |  | — |  |  | — |  |  | 942 |  |  | (157 | ) |  | 153 |
Subtotal |  | $ | — |  |  | — |  |  | — |  |  | 942 |  |  | (157 | ) |  | 153 |
Total AFS and HTM |  | $ | 879,619 |  |  | (21,084 | ) |  | — |  |  | 145,401 |  |  | (2,917 | ) |  | 153 |
December 31, 2014 |  | Less than 12 months |  | 12 months or longer
($ in thousands) |  | Fair Value |  | Unrealized Losses 1 |  | Fair Value |  | Unrealized Losses 1
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 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 |
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 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) |  |
September 30, 2015 |  | December 31, 2014
Number of Issues | % of Market/Book | Unrealized/ Unrecognized Loss |  | Number of Issues | % of Market/Book | Unrealized/ Unrecognized Loss
389 |  | 80% - 99% | $ | 21,841 |  |  | 350 |  | 80% - 99% | $ | 10,596 |
4 |  | 60% - 79% | 2,007 |  |  | — |  | 60% - 79% | — |
— |  | 40% - 59% | — |  |  | — |  | 40% - 59% | — |
— |  | 20% - 39% | — |  |  | — |  | 20% - 39% | — |
— |  | 0% - 19% | — |  |  | — |  | 0% - 19% | — |
|  |  | $ | 23,848 |  |  |  |  |  | $ | 10,596 |
We do not intend to sell any of the securities in the tables above, nor do we believe we will be required to sell any of these securities. We have also reviewed these securities under our OTTI policy, as described in Note 2. “Summary of Significant Accounting Policies” within Item 8. “Financial Statements and Supplementary Data.” of our 2014 Annual Report, and have concluded that they are temporarily impaired. This conclusion reflects our current judgment as to the financial position and future prospects of the entity that issued the investment security and underlying collateral. If our judgment about an individual security changes in the future, we may ultimately record a credit loss after having originally concluded that one did not exist, which could have a material impact on our net income and financial position in future periods.
Schedule of Other Investment Portfolio By Strategy And Remaining Commitment Amount Associated With Each Strategy |
Other Investments |  | Carrying Value |  | September 30, 2015
($ in thousands) |  | September 30, 2015 |  | December 31, 2014 |  | Remaining Commitment
Alternative Investments |  |  |  |  |  |  |  |  |
Secondary private equity |  | $ | 17,503 |  |  | 21,807 |  |  | 7,095 |
Private equity |  | 15,792 |  |  | 20,126 |  |  | 23,826 |
Energy/power generation |  | 11,643 |  |  | 14,445 |  |  | 16,857 |
Real estate |  | 8,854 |  |  | 11,452 |  |  | 9,919 |
Mezzanine financing |  | 6,948 |  |  | 9,853 |  |  | 13,383 |
Distressed debt |  | 6,889 |  |  | 8,679 |  |  | 3,048 |
Venture capital |  | 6,539 |  |  | 6,606 |  |  | 150 |
Total alternative investments |  | 74,168 |  |  | 92,968 |  |  | 74,278 |
Other securities |  | 10,978 |  |  | 6,235 |  |  | 2,269 |
Total other investments |  | $ | 85,146 |  |  | 99,203 |  |  | 76,547 |
Schedule of Aggregated Summarized Income Statement Financial Information For Partnerships In Our Alternative Investment Portfolio |
Income Statement Information |  | Quarter ended June 30, |  | Nine months ended June 30,
($ in millions) |  | 2015 |  | 2014 |  | 2015 |  | 2014
Net investment income |  | $ | 44.1 |  |  | 81.3 |  |  | $ | 139.6 |  |  | 167.0 |
Realized gains (losses) |  | 385.2 |  |  | (26.1 | ) |  | 977.7 |  |  | 171.5 |
Net change in unrealized (depreciation) appreciation |  | (222.2 | ) |  | 628.6 |  |  | (1,089.0 | ) |  | 1,471.0 |
Net income |  | $ | 207.1 |  |  | 683.8 |  |  | $ | 28.3 |  |  | 1,809.5 |
Selective’s insurance subsidiaries’ other investments income (loss) |  | $ | 1.3 |  |  | 3.9 |  |  | $ | (0.8 | ) |  | 12.7 |
Schedule of Securities Pledged As Collateral |
($ in millions) |  | FHLBI Collateral |  | Reinsurance Collateral |  | State and Regulatory Deposits |  | Total
U.S. government and government agencies |  | $ | 7.7 |  |  | — |  |  | 24.4 |  |  | 32.1 |
Obligations of states and political subdivisions |  | — |  |  | 5.0 |  |  | — |  |  | 5.0 |
Corporate securities |  | — |  |  | 4.8 |  |  | — |  |  | 4.8 |
CMBS |  | 1.4 |  |  | — |  |  | — |  |  | 1.4 |
RMBS |  | 55.5 |  |  | 1.9 |  |  | — |  |  | 57.4 |
Total pledged as collateral |  | $ | 64.6 |  |  | 11.7 |  |  | 24.4 |  |  | 100.7 |
Schedule of Net Investment Income Earned |
|  | Quarter ended September 30, |  | Nine Months ended September 30,
($ in thousands) |  | 2015 |  | 2014 |  | 2015 |  | 2014
Fixed income securities |  | $ | 30,601 |  |  | 30,706 |  |  | $ | 92,227 |  |  | 95,515 |
Equity securities |  | 2,370 |  |  | 1,909 |  |  | 6,546 |  |  | 5,094 |
Short-term investments |  | 24 |  |  | 15 |  |  | 72 |  |  | 48 |
Other investments |  | 1,337 |  |  | 3,906 |  |  | (781 | ) |  | 12,677 |
Investment expenses |  | (2,271 | ) |  | (2,244 | ) |  | (6,856 | ) |  | (6,734 | )
Net investment income earned |  | $ | 32,061 |  |  | 34,292 |  |  | $ | 91,208 |  |  | 106,600 |
Schedule of OTTI By Asset Type |
Third Quarter 2015 |  | Gross |  | Included in Other Comprehensive Income ("OCI") |  | Recognized in Earnings
($ in thousands) |  |  |
AFS fixed income securities: |  |  |  |  |  |
Corporate securities |  | $ | 253 |  |  | — |  |  | 253 |
Total AFS fixed income securities |  | 253 |  |  | — |  |  | 253 |
AFS equity securities: |  |  |  |  |  |
Common stock |  | 1,029 |  |  | — |  |  | 1,029 |
Total AFS equity securities |  | 1,029 |  |  | — |  |  | 1,029 |
Total OTTI losses |  | $ | 1,282 |  |  | — |  |  | 1,282 |
Nine Months 2015 |  | Gross |  | Included in OCI |  | Recognized in Earnings
($ in thousands) |  |  |
AFS fixed income securities: |  |  |  |  |  |
Corporate securities |  | $ | 1,445 |  |  | — |  |  | 1,445 |
RMBS |  | 1 |  |  | — |  |  | 1 |
Total AFS fixed income securities |  | 1,446 |  |  | — |  |  | 1,446 |
AFS equity securities: |  |  |  |  |  |
Common stock |  | 6,201 |  |  | — |  |  | 6,201 |
Preferred stock |  | 180 |  |  | — |  |  | 180 |
Total AFS equity securities |  | 6,381 |  |  | — |  |  | 6,381 |
Total OTTI losses |  | $ | 7,827 |  |  | — |  |  | 7,827 |
Nine Months 2014 |  | Gross |  | Included in OCI |  | Recognized in Earnings
($ in thousands) |  |  |
AFS equity securities: |  |  |  |  |  |  |  |  |
Common stock |  | $ | 1,382 |  |  | — |  |  | 1,382 |
Total OTTI losses |  | $ | 1,382 |  |  | — |  |  | 1,382 |
Schedule of Gross Credit Loss Impairments on Fixed Maturity Securities for Which a Portion of the OTTI Charge was Recognized in OCI |
|  | Quarter ended September 30,
($ in thousands) |  | 2015 |  | 2014
Balance, beginning of period |  | $ | 1,013 |  |  | 5,534 |
Addition for the amount related to credit loss for which an OTTI was not previously recognized |  | — |  |  | — |
Reductions for securities sold during the period |  | — |  |  | (90 | )
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 |  | — |  |  | — |
Additional increases to the amount related to credit loss for which an OTTI was previously recognized |  | — |  |  | — |
Accretion of credit loss impairments previously recognized due to an increase in cash flows expected to be collected |  | — |  |  | — |
Balance, end of period |  | $ | 1,013 |  |  | 5,444 |
|  | Nine Months ended September 30,
($ in thousands) |  | 2015 |  | 2014
Balance, beginning of period |  | $ | 5,444 |  |  | 7,488 |
Addition for the amount related to credit loss for which an OTTI was not previously recognized |  | — |  |  | — |
Reductions for securities sold during the period |  | (4,431 | ) |  | (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 |  | — |  |  | — |
Additional increases to the amount related to credit loss for which an OTTI was previously recognized |  | — |  |  | — |
Accretion of credit loss impairments previously recognized due to an increase in cash flows expected to be collected |  | — |  |  | — |
Balance, end of period |  | $ | 1,013 |  |  | 5,444 |
Schedule of Components of Net Realized Gains Excluding OTTI Charges |
|  | Quarter ended September 30, |  | Nine Months ended September 30,
($ in thousands) |  | 2015 |  | 2014 |  | 2015 |  | 2014
HTM fixed income securities |  |  |  |  |  |  |  |
Gains |  | $ | 3 |  |  | — |  |  | 5 |  |  | 3 |
Losses |  | — |  |  | (4 | ) |  | (1 | ) |  | (18 | )
AFS fixed income securities |  |  |  |  |  |  |  |  |  |  |  |
Gains |  | 169 |  |  | 695 |  |  | 2,158 |  |  | 1,633 |
Losses |  | — |  |  | (29 | ) |  | (130 | ) |  | (172 | )
AFS equity securities |  |  |  |  |  |  |  |  |  |  |  |
Gains |  | 1,419 |  |  | 14,576 |  |  | 23,567 |  |  | 27,255 |
Losses |  | (1 | ) |  | (8 | ) |  | (1,347 | ) |  | (332 | )
Other investments |  |  |  |  |  |  |  |
Gains |  | — |  |  | 1 |  |  | — |  |  | 1 |
Losses |  | — |  |  | — |  |  | (654 | ) |  | — |
Total net realized gains (excluding OTTI charges) |  | $ | 1,590 |  |  | 15,231 |  |  | 23,598 |  |  | 28,370 |
Held To Maturity Fixed Income Securities [Member] |
Investments [Line Items] |
Schedule of Fixed Maturity Securities By Contractual Maturities |
($ in thousands) |  | Carrying Value |  | Fair Value
Due in one year or less |  | $ | 102,507 |  |  | 103,945 |
Due after one year through five years |  | 116,833 |  |  | 123,960 |
Due after five years through 10 years |  | 10,529 |  |  | 12,483 |
Total HTM fixed income securities |  | $ | 229,869 |  |  | 240,388 |
AFS Fixed Income Securities [Member] |
Investments [Line Items] |
Schedule of Fixed Maturity Securities By Contractual Maturities |
($ in thousands) |  | Fair Value
Due in one year or less |  | $ | 501,398 |
Due after one year through five years |  | 2,180,671 |
Due after five years through 10 years |  | 1,589,038 |
Due after 10 years |  | 79,939 |
Total AFS fixed income securities |  | $ | 4,351,046 |

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