v2.4.0.8

Investments (Details) (USD $) | Jun. 30, 2013 | Dec. 31, 2012
--- | --- | ---
U.S. Treasury obligations [Member] |  |  |  |
Fixed maturities, available for sale |  |  |  |
Amortized Cost | $ 206,778,000 |  | $ 191,642,000 |
Gross Unrealized Gains | 8,427,000 |  | 14,266,000 |
Gross Unrealized Losses | (1,383,000) |  | (51,000) |
Total Fair Value | 213,822,000 |  | 205,857,000 |
U.S. Government-sponsored enterprise obligations [Member] |  |  |  |
Fixed maturities, available for sale |  |  |  |
Amortized Cost | 53,486,000 |  | 52,110,000 |
Gross Unrealized Gains | 3,732,000 |  | 4,837,000 |
Gross Unrealized Losses | (293,000) |  | 0 |
Total Fair Value | 56,925,000 |  | 56,947,000 |
State and municipal bonds [Member] |  |  |  |
Fixed maturities, available for sale |  |  |  |
Amortized Cost | 1,204,739,000 |  | 1,134,744,000 |
Gross Unrealized Gains | 55,546,000 |  | 85,329,000 |
Gross Unrealized Losses | (7,113,000) |  | (94,000) |
Total Fair Value | 1,253,172,000 |  | 1,219,979,000 |
Corporate debt [Member] |  |  |  |
Fixed maturities, available for sale |  |  |  |
Amortized Cost | 1,502,700,000 |  | 1,375,880,000 |
Gross Unrealized Gains | 60,506,000 |  | 96,187,000 |
Gross Unrealized Losses | (16,314,000) |  | (1,543,000) |
Total Fair Value | 1,546,892,000 |  | 1,470,524,000 |
Residential mortgage-backed securities [Member] |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Accumulated Other Comprehensive Income (Loss), Other than Temporary Impairment, Not Credit Loss, Net of Tax, Available-for-sale, Debt Securities | 500,000 |  | 900,000 |
Fixed maturities, available for sale |  |  |  |
Amortized Cost | 263,844,000 |  | 272,990,000 |
Gross Unrealized Gains | 10,382,000 |  | 17,070,000 |
Gross Unrealized Losses | (1,993,000) | [1] | (210,000) | [1]
Total Fair Value | 272,233,000 |  | 289,850,000 |
Agency commercial mortgage-backed securities [Member] |  |  |  |
Fixed maturities, available for sale |  |  |  |
Amortized Cost | 43,696,000 |  | 57,234,000 |
Gross Unrealized Gains | 822,000 |  | 2,255,000 |
Gross Unrealized Losses | (69,000) |  | (25,000) |
Total Fair Value | 44,449,000 |  | 59,464,000 |
Other commercial mortgage-backed securities [Member] |  |  |  |
Fixed maturities, available for sale |  |  |  |
Amortized Cost | 67,861,000 |  | 69,062,000 |
Gross Unrealized Gains | 3,264,000 |  | 5,049,000 |
Gross Unrealized Losses | (260,000) |  | (5,000) |
Total Fair Value | 70,865,000 |  | 74,106,000 |
Other asset-backed securities [Member] |  |  |  |
Fixed maturities, available for sale |  |  |  |
Amortized Cost | 75,843,000 |  | 70,670,000 |
Gross Unrealized Gains | 625,000 |  | 1,203,000 |
Gross Unrealized Losses | (393,000) |  | (601,000) |
Total Fair Value | 76,075,000 |  | 71,272,000 |
Debt Securities [Member] |  |  |  |
Fixed maturities, available for sale |  |  |  |
Amortized Cost | 3,418,947,000 |  | 3,224,332,000 |
Gross Unrealized Gains | 143,304,000 |  | 226,196,000 |
Gross Unrealized Losses | (27,818,000) |  | (2,529,000) |
Total Fair Value | $ 3,534,433,000 |  | $ 3,447,999,000 |
[1] | Includes other-than-temporary impairments recognized in accumulated other comprehensive income of $0.5 million and $0.9 million at June 30, 2013 and December 31, 2012, respectively.

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