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Investments (Tables) | 6 Months Ended
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Jun. 30, 2013
Gross Unrealized Gains and Losses and Cost and Fair Value of Investments Classified as Held-to-maturity | The gross unrealized gains and losses on, and the cost and fair value of, those investments classified as held-to-maturity at June 30, 2013 are summarized as follows:
|  | Cost or Amortized Cost |  |  | Gross Unrealized Gains |  |  | Gross Unrealized Losses |  |  | Fair Value |
|  | (in thousands) |
States and political subdivisions |  | $ | 395,641 |  |  | $ | 21,298 |  |  | $ | (1,262 | ) |  | $ | 415,677 |
Corporate bonds |  |  | 77,235 |  |  |  | 1,045 |  |  |  | (74 | ) |  |  | 78,206 |
Commercial mortgage-backed securities |  |  | 51,502 |  |  |  | 4,230 |  |  |  | — |  |  |  | 55,732 |
U.S. agency-based mortgage-backed securities |  |  | 26,732 |  |  |  | 2,179 |  |  |  | — |  |  |  | 28,911 |
U.S. Treasury securities and obligations of U.S. government agencies |  |  | 11,020 |  |  |  | 1,205 |  |  |  | — |  |  |  | 12,225 |
Asset-backed securities |  |  | 3,744 |  |  |  | 216 |  |  |  | (180 | ) |  |  | 3,780 |
Totals |  | $ | 565,874 |  |  | $ | 30,173 |  |  | $ | (1,516 | ) |  | $ | 594,531 |
The gross unrealized gains and losses on, and the cost and fair value of, those investments classified as held-to-maturity at December 31, 2012 are summarized as follows:
|  | Cost or Amortized Cost |  |  | Gross Unrealized Gains |  |  | Gross Unrealized Losses |  |  | Fair Value |
|  | (in thousands) |
States and political subdivisions |  | $ | 400,687 |  |  | $ | 31,387 |  |  | $ | (106 | ) |  | $ | 431,968 |
Corporate bonds |  |  | 82,824 |  |  |  | 1,565 |  |  |  | (12 | ) |  |  | 84,377 |
Commercial mortgage-backed securities |  |  | 51,529 |  |  |  | 6,433 |  |  |  | — |  |  |  | 57,962 |
U.S. agency-based mortgage-backed securities |  |  | 32,984 |  |  |  | 3,063 |  |  |  | (5 | ) |  |  | 36,042 |
U.S. Treasury securities and obligations of U.S. Government agencies |  |  | 11,034 |  |  |  | 1,721 |  |  |  | — |  |  |  | 12,755 |
Asset-backed securities |  |  | 4,229 |  |  |  | 192 |  |  |  | (176 | ) |  |  | 4,245 |
Totals |  | $ | 583,287 |  |  | $ | 44,361 |  |  | $ | (299 | ) |  | $ | 627,349 |
Gross Unrealized Gains and Losses and Cost and Fair Value of Investments Classified as Available-for-sale | The gross unrealized gains and losses on, and the cost and fair value of, those investments classified as available-for-sale at June 30, 2013 are summarized as follows:
|  | Cost |  |  | Gross Unrealized Gains |  |  | Gross Unrealized Losses |  |  | Fair Value |
|  | (in thousands) |
Fixed maturity: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
States and political subdivisions |  | $ | 132,603 |  |  | $ | 2,229 |  |  | $ | (2,567 | ) |  | $ | 132,265 |
Corporate bonds |  |  | 58,566 |  |  |  | 377 |  |  |  | (273 | ) |  |  | 58,670 |
U.S. agency-based mortgage-backed securities |  |  | 10,418 |  |  |  | 2 |  |  |  | (1,981 | ) |  |  | 8,439 |
Total fixed maturity |  |  | 201,587 |  |  |  | 2,608 |  |  |  | (4,821 | ) |  |  | 199,374 |
Equity securities |  |  | 13,881 |  |  |  | 345 |  |  |  | (728 | ) |  |  | 13,498 |
Totals |  | $ | 215,468 |  |  | $ | 2,953 |  |  | $ | (5,549 | ) |  | $ | 212,872 |
The gross unrealized gains and losses on, and the cost and fair value of, those investments classified as available-for-sale at December 31, 2012 are summarized as follows:
|  | Cost |  |  | Gross Unrealized Gains |  |  | Gross Unrealized Losses |  |  | Fair Value |
|  | (in thousands) |
Fixed maturity: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
States and political subdivisions |  | $ | 93,362 |  |  | $ | 5,022 |  |  | $ | (142 | ) |  | $ | 98,242 |
Corporate bonds |  |  | 39,211 |  |  |  | 623 |  |  |  | (24 | ) |  |  | 39,810 |
U.S. agency-based mortgage-backed securities |  |  | 11,941 |  |  |  | 5 |  |  |  | (859 | ) |  |  | 11,087 |
Total fixed maturity |  |  | 144,514 |  |  |  | 5,650 |  |  |  | (1,025 | ) |  |  | 149,139 |
Equity securities |  |  | 7,000 |  |  |  | 451 |  |  |  | (685 | ) |  |  | 6,766 |
Totals |  | $ | 151,514 |  |  | $ | 6,101 |  |  | $ | (1,710 | ) |  | $ | 155,905 |
Investment Securities Continuous Unrealized Loss Position | The following table summarizes, as of June 30, 2013, gross unrealized losses on a total of 158 securities that were at a loss for either less than twelve months or twelve months or greater:
|  | As of June 30, 2013 |
|  | Less Than 12 Months |  |  | 12 Months or Greater |  |  | Total |
|  | Fair Value of Investments with Unrealized Losses |  |  | Gross Unrealized Losses |  |  | Fair Value of Investments with Unrealized Losses |  |  | Gross Unrealized Losses |  |  | Fair Value of Investments with Unrealized Losses |  |  | Gross Unrealized Losses |
|  | (in thousands) |
Held-to-Maturity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed maturity securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Corporate bonds |  | $ | 29,035 |  |  | $ | 74 |  |  | $ | — |  |  | $ | — |  |  | $ | 29,035 |  |  | $ | 74 |
States and political subdivisions |  |  | 47,223 |  |  |  | 1,262 |  |  |  | — |  |  |  | — |  |  |  | 47,223 |  |  |  | 1,262 |
U.S. agency-based mortgage-backed securities |  |  | — |  |  |  | — |  |  |  | 9 |  |  |  | — |  |  |  | 9 |  |  |  | — |
Asset-backed securities |  |  | — |  |  |  | — |  |  |  | 2,047 |  |  |  | 180 |  |  |  | 2,047 |  |  |  | 180 |
Total held-to-maturity securities |  |  | 76,258 |  |  |  | 1,336 |  |  |  | 2,056 |  |  |  | 180 |  |  |  | 78,314 |  |  |  | 1,516 |
Available-for-Sale |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed maturity securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Corporate bonds |  | $ | 26,823 |  |  | $ | 273 |  |  | $ | — |  |  | $ | — |  |  | $ | 26,823 |  |  | $ | 273 |
States and political subdivisions |  |  | 69,199 |  |  |  | 2,567 |  |  |  | — |  |  |  | — |  |  |  | 69,199 |  |  |  | 2,567 |
U.S. agency-based mortgage-backed securities |  |  | 8,309 |  |  |  | 1,981 |  |  |  | — |  |  |  | — |  |  |  | 8,309 |  |  |  | 1,981 |
Equity securities |  |  | 3,917 |  |  |  | 728 |  |  |  | — |  |  |  | — |  |  |  | 3,917 |  |  |  | 728 |
Total available-for-sale securities |  |  | 108,248 |  |  |  | 5,549 |  |  |  | — |  |  |  | — |  |  |  | 108,248 |  |  |  | 5,549 |
Total |  | $ | 184,506 |  |  | $ | 6,885 |  |  | $ | 2,056 |  |  | $ | 180 |  |  | $ | 186,562 |  |  | $ | 7,065 |
The following table summarizes, as of December 31, 2012, gross unrealized losses on a total of 49 securities that were at a loss for either less than twelve months or twelve months or greater:
|  | As of December 31, 2012 |
|  | Less Than 12 Months |  |  | 12 Months or Greater |  |  | Total |
|  | Fair Value of Investments with Unrealized Losses |  |  | Gross Unrealized Losses |  |  | Fair Value of Investments with Unrealized Losses |  |  | Gross Unrealized Losses |  |  | Fair Value of Investments with Unrealized Losses |  |  | Gross Unrealized Losses |
|  | (in thousands) |
Held-to-Maturity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed maturity securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Corporate bonds |  | $ | 10,734 |  |  | $ | 12 |  |  | $ | — |  |  | $ | — |  |  | $ | 10,734 |  |  | $ | 12 |
State and political subdivisions |  |  | 11,913 |  |  |  | 106 |  |  |  | — |  |  |  | — |  |  |  | 11,913 |  |  |  | 106 |
U.S. agency-based mortgage-backed securities |  |  | 117 |  |  |  | — |  |  |  | 68 |  |  |  | 5 |  |  |  | 185 |  |  |  | 5 |
Asset-backed securities |  |  | — |  |  |  | — |  |  |  | 2,277 |  |  |  | 176 |  |  |  | 2,277 |  |  |  | 176 |
Total held-to-maturity securities |  |  | 22,764 |  |  |  | 118 |  |  |  | 2,345 |  |  |  | 181 |  |  |  | 25,109 |  |  |  | 299 |
Available-for-Sale |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed maturity securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Corporate bonds |  | $ | 6,411 |  |  | $ | 24 |  |  | $ | — |  |  | $ | — |  |  | $ | 6,411 |  |  | $ | 24 |
States and political subdivisions |  |  | 6,281 |  |  |  | 142 |  |  |  | — |  |  |  | — |  |  |  | 6,281 |  |  |  | 142 |
U.S. agency-based mortgage-backed securities |  |  | 10,919 |  |  |  | 859 |  |  |  | — |  |  |  | — |  |  |  | 10,919 |  |  |  | 859 |
Equity securities |  |  | 4,186 |  |  |  | 685 |  |  |  | — |  |  |  | — |  |  |  | 4,186 |  |  |  | 685 |
Total available-for-sale securities |  |  | 27,797 |  |  |  | 1,710 |  |  |  | — |  |  |  | — |  |  |  | 27,797 |  |  |  | 1,710 |
Total |  | $ | 50,561 |  |  | $ | 1,828 |  |  | $ | 2,345 |  |  | $ | 181 |  |  | $ | 52,906 |  |  | $ | 2,009 |
Total held-to-maturity securities [Member] |
Summary of Amortized Cost and Fair Value of Investments in Fixed Maturity Securities, by Contractual Maturity | A summary of the cost or amortized cost and fair value of investments in fixed maturity securities, classified as held-to-maturity at June 30, 2013, by contractual maturity, is as follows:
Remaining Time to Maturity |  | Amortized Cost Basis |  |  | Fair Value |
|  | (in thousands) |
Less than one year |  | $ | 66,726 |  |  | $ | 67,210 |
One to five years |  |  | 143,021 |  |  |  | 150,147 |
Five to ten years |  |  | 132,814 |  |  |  | 143,055 |
More than ten years |  |  | 141,335 |  |  |  | 145,696 |
U.S. agency-based mortgage-backed securities |  |  | 26,732 |  |  |  | 28,911 |
Commercial mortgage-backed securities |  |  | 51,502 |  |  |  | 55,732 |
Asset-backed securities |  |  | 3,744 |  |  |  | 3,780 |
Total |  | $ | 565,874 |  |  | $ | 594,531 |
Total available-for-sale securities [Member] |
Summary of Amortized Cost and Fair Value of Investments in Fixed Maturity Securities, by Contractual Maturity | A summary of the cost or amortized cost and fair value of investments in fixed maturity securities, classified as available-for-sale at June 30, 2013, by contractual maturity, is as follows:
Remaining Time to Maturity |  | Cost Basis |  |  | Fair Value |
|  | (in thousands) |
Less than one year |  | $ | 30,653 |  |  | $ | 30,679 |
One to five years |  |  | 21,431 |  |  |  | 21,653 |
Five to ten years |  |  | 18,252 |  |  |  | 18,370 |
More than ten years |  |  | 120,833 |  |  |  | 120,233 |
U.S. agency-based mortgage-backed securities |  |  | 10,418 |  |  |  | 8,439 |
Total |  | $ | 201,587 |  |  | $ | 199,374 |

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- Definition Tabular disclosure of maturities of an entity's investments as well as any other information pertinent to the investments. + References No definition available. + Details
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- Definition Tabular disclosure of the reconciliation of available-for-sale securities from cost basis to fair value. + References No definition available. + Details
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- Definition For all investments in an unrealized loss position, including those for which other-than-temporary impairments have not been recognized in earnings (including investments for which a portion of an other-than-temporary impairment has been recognized in other comprehensive income), a tabular disclosure of the aggregate related fair value of investments with unrealized losses and the aggregate amount of unrealized losses (that is, the amount by which amortized cost basis exceeds fair value). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
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