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Fair Value Measurements (Tables) | 9 Months Ended
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Sep. 30, 2013
Fair Value Disclosures [Abstract] |
Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis | At September 30, 2013, assets and liabilities measured at fair value on a recurring basis are summarized below:
|  | Level 1 Inputs |  |  | Level 2 Inputs |  |  | Level 3 Inputs |  |  | Total Fair Value |
|  | (in thousands) |
Financial instruments carried at fair value, classified as a part of: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other investments |  | $ | — |  |  | $ | — |  |  | $ | 10,271 |  |  | $ | 10,271 |
Securities available for sale—equity: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Domestic common stock |  |  | 12,260 |  |  |  | — |  |  |  | — |  |  |  | 12,260 |
Securities available for sale—fixed maturity: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
States and political subdivisions |  |  | — |  |  |  | 130,558 |  |  |  | — |  |  |  | 130,558 |
Corporate bonds |  |  | — |  |  |  | 64,102 |  |  |  | — |  |  |  | 64,102 |
U.S. agency-based mortgage-backed securities |  |  | — |  |  |  | 8,041 |  |  |  | — |  |  |  | 8,041 |
Total securities available for sale—fixed maturity |  |  | — |  |  |  | 202,701 |  |  |  | — |  |  |  | 202,701 |
Total available for sale |  | $ | 12,260 |  |  | $ | 202,701 |  |  | $ | 10,271 |  |  | $ | 225,232 |
At December 31, 2012, assets and liabilities measured at fair value on a recurring basis are summarized below:
|  | Level 1 Inputs |  |  | Level 2 Inputs |  |  | Level 3 Inputs |  |  | Total Fair Value |
|  | (in thousands) |
Securities available for sale—equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Domestic common stock |  | $ | 6,766 |  |  | $ | — |  |  | $ | — |  |  | $ | 6,766 |
Securities available for sale—fixed maturity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
States and political subdivisions |  |  | — |  |  |  | 98,242 |  |  |  | — |  |  |  | 98,242 |
Corporate bonds |  |  | — |  |  |  | 39,810 |  |  |  | — |  |  |  | 39,810 |
U.S. agency-based mortgage-backed securities |  |  | — |  |  |  | 11,087 |  |  |  | — |  |  |  | 11,087 |
Total available for sale—fixed maturity |  |  | — |  |  | $ | 149,139 |  |  | $ | — |  |  | $ | 149,139 |
Total available for sale |  | $ | 6,766 |  |  | $ | 149,139 |  |  | $ | — |  |  | $ | 155,905 |
Schedule of Assets and Liabilities Measured at Amortized Cost | At September 30, 2013, assets and liabilities measured at amortized cost are summarized below:
|  | Level 1 Inputs |  |  | Level 2 Inputs |  |  | Level 3 Inputs |  |  | Total Fair Value |
|  | (in thousands) |
Securities held-to-maturity—fixed maturity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
States and political subdivisions |  | $ | — |  |  | $ | 407,582 |  |  | $ | — |  |  | $ | 407,582 |
Corporate bonds |  |  | — |  |  |  | 72,072 |  |  |  | — |  |  |  | 72,072 |
Commercial mortgage-backed securities |  |  | — |  |  |  | 55,275 |  |  |  | — |  |  |  | 55,275 |
U.S. agency-based mortgage-backed securities |  |  | — |  |  |  | 25,842 |  |  |  | — |  |  |  | 25,842 |
U.S. Treasury securities and obligations of U.S. Government agencies |  |  | 6,640 |  |  |  | 6,012 |  |  |  | — |  |  |  | 12,652 |
Asset-backed securities |  |  | — |  |  |  | 3,566 |  |  |  | — |  |  |  | 3,566 |
Total held-to-maturity |  | $ | 6,640 |  |  | $ | 570,349 |  |  | $ | — |  |  | $ | 576,989 |
At December 31, 2012, assets and liabilities measured at amortized cost are summarized below:
|  | Level 1 Inputs |  |  | Level 2 Inputs |  |  | Level 3 Inputs |  |  | Total Fair Value |
|  | (in thousands) |
Securities held-to-maturity—fixed maturity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
States and political subdivisions |  | $ | — |  |  | $ | 431,968 |  |  | $ | — |  |  | $ | 431,968 |
Corporate bonds |  |  | — |  |  |  | 84,377 |  |  |  | — |  |  |  | 84,377 |
Commercial mortgage-backed securities |  |  | — |  |  |  | 57,962 |  |  |  | — |  |  |  | 57,962 |
U.S. agency-based mortgage-backed securities |  |  | — |  |  |  | 36,042 |  |  |  | — |  |  |  | 36,042 |
U.S. Treasury securities and obligations of U.S. Government agencies |  |  | 6,174 |  |  |  | 6,581 |  |  |  | — |  |  |  | 12,755 |
Asset-backed securities |  |  | — |  |  |  | 4,245 |  |  |  | — |  |  |  | 4,245 |
Total held-to-maturity |  | $ | 6,174 |  |  | $ | 621,175 |  |  | $ | — |  |  | $ | 627,349 |
Summary of Carrying Values and Corresponding Fair Values for Financial Instruments | The following table summarizes the carrying values and corresponding fair values for financial instruments:
|  | As of September 30, 2013 |  |  | As of December 31, 2012 |
|  | Carrying Amount |  |  | Fair Value |  |  | Carrying Amount |  |  | Fair Value |
|  | (in thousands) |
Assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed maturity securities—held-to-maturity |  | $ | 550,153 |  |  | $ | 576,989 |  |  | $ | 583,287 |  |  | $ | 627,349 |
Fixed maturity securities—available-for-sale |  |  | 202,701 |  |  |  | 202,701 |  |  |  | 149,139 |  |  |  | 149,139 |
Equity securities |  |  | 12,260 |  |  |  | 12,260 |  |  |  | 6,766 |  |  |  | 6,766 |
Cash and cash equivalents |  |  | 116,778 |  |  |  | 116,778 |  |  |  | 92,676 |  |  |  | 92,676 |
Short-term Investments |  |  | 86,131 |  |  |  | 86,131 |  |  |  | 68,924 |  |  |  | 68,924 |
Other Investments |  |  | 10,271 |  |  |  | 10,271 |  |  |  | — |  |  |  | — |
Summary of Changes in Fair Value of Assets Measured at Fair Value | The following table presents summary information regarding changes in the fair value of assets measured at fair value using Level 3 input.
|  | September 30, 2013 |
|  | (in thousands) |
Balance at January 1, 2013 |  | $ | — |
Purchases |  |  | 10,000 |
Total gains unrealized (Included in earnings as part of net investment income) |  |  | 271 |
Balance at September 30, 2013 |  | $ | 10,271 |

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- Definition Tabular disclosure of the fair value measurement of assets using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes during the period attributable to the following: (1) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets) and gains or losses recognized in other comprehensive income (loss), and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (2) purchases, sales, issues, and settlements (each type disclosed separately); and (3) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs), by class of asset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19279-110258 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 + Details
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- Definition Tabular disclosure of the fair value of financial instruments, including financial assets and financial liabilities, and the measurements of those instruments, assets, and liabilities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13433-108611 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13467-108611 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13476-108611 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 30 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14172-108612 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6447952&loc=d3e13220-108610 + Details
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- Definition Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19190-110258 + Details
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