v2.4.0.8

Investments (Details 4) (USD $) In Thousands, unless otherwise specified | Jun. 30, 2013 | Dec. 31, 2012
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Investments in LPs/LLCs [Member] |  |
Investments held in an unrealized loss position |  |
Other Investments, Continuous Unrealized Loss Position, Fair Value | $ 4,972 | $ 9,474
Other Investments, Continuous Unrealized Loss Position, Aggregate Losses | (325) | (851)
Other investments, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | 3,906 | 8,697
Other Investments, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Losses | (294) | (688)
Other Investments, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | 1,066 | 777
Other Investments, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses | (31) | (163)
U.S. Treasury obligations [Member] |  |
Investments held in an unrealized loss position |  |
Fair Value | 54,610 | 4,073
Unrealized Loss | (1,383) | (51)
Less than 12 months, Fair Value | 54,610 | 4,073
Less than 12 months, Unrealized Loss | (1,383) | (51)
More than 12 months, Fair Value | 0 | 0
More than 12 months, Unrealized Loss | 0 | 0
US Government-sponsored Enterprises Debt Securities [Member] |  |
Investments held in an unrealized loss position |  |
Fair Value | 5,579 |
Unrealized Loss | (293) |
Less than 12 months, Fair Value | 5,579 |
Less than 12 months, Unrealized Loss | (293) |
More than 12 months, Fair Value | 0 |
More than 12 months, Unrealized Loss | 0 |
State and municipal bonds [Member] |  |
Investments held in an unrealized loss position |  |
Fair Value | 210,096 | 11,234
Unrealized Loss | (7,113) | (94)
Less than 12 months, Fair Value | 208,105 | 9,232
Less than 12 months, Unrealized Loss | (7,089) | (65)
More than 12 months, Fair Value | 1,991 | 2,002
More than 12 months, Unrealized Loss | (24) | (29)
Corporate debt [Member] |  |
Investments held in an unrealized loss position |  |
Fair Value | 423,388 | 90,154
Unrealized Loss | (16,314) | (1,543)
Less than 12 months, Fair Value | 416,240 | 81,878
Less than 12 months, Unrealized Loss | (15,961) | (1,377)
More than 12 months, Fair Value | 7,148 | 8,276
More than 12 months, Unrealized Loss | (353) | (166)
Residential mortgage-backed securities [Member] |  |
Investments held in an unrealized loss position |  |
Fair Value | 75,441 | 10,721
Unrealized Loss | (1,993) | (210)
Less than 12 months, Fair Value | 74,789 | 10,029
Less than 12 months, Unrealized Loss | (1,990) | (205)
More than 12 months, Fair Value | 652 | 692
More than 12 months, Unrealized Loss | (3) | (5)
Agency commercial mortgage-backed securities [Member] |  |
Investments held in an unrealized loss position |  |
Fair Value | 5,252 | 1,643
Unrealized Loss | (69) | (25)
Less than 12 months, Fair Value | 4,765 | 498
Less than 12 months, Unrealized Loss | (59) | (2)
More than 12 months, Fair Value | 487 | 1,145
More than 12 months, Unrealized Loss | (10) | (23)
Other commercial mortgage-backed securities [Member] |  |
Investments held in an unrealized loss position |  |
Fair Value | 13,309 | 2,100
Unrealized Loss | (260) | (5)
Less than 12 months, Fair Value | 13,309 | 1,103
Less than 12 months, Unrealized Loss | (260) | (1)
More than 12 months, Fair Value | 0 | 997
More than 12 months, Unrealized Loss | 0 | (4)
Other asset-backed securities [Member] |  |
Investments held in an unrealized loss position |  |
Fair Value | 26,728 | 10,746
Unrealized Loss | (393) | (601)
Less than 12 months, Fair Value | 23,397 | 7,707
Less than 12 months, Unrealized Loss | (158) | (20)
More than 12 months, Fair Value | 3,331 | 3,039
More than 12 months, Unrealized Loss | (235) | (581)
Debt Securities [Member] |  |
Investments held in an unrealized loss position |  |
Fair Value | 814,403 | 130,671
Unrealized Loss | (27,818) | (2,529)
Less than 12 months, Fair Value | 800,794 | 114,520
Less than 12 months, Unrealized Loss | (27,193) | (1,721)
More than 12 months, Fair Value | 13,609 | 16,151
More than 12 months, Unrealized Loss | $ (625) | $ (808)

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