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Fair Values of Financial Instruments (Tables) | 12 Months Ended
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Dec. 31, 2014
Fair Value Disclosures [Abstract] |
Summary of Carrying Values and Corresponding Fair Values for Financial Instruments | The following table summarizes the carrying or reported values and corresponding fair values for financial instruments:
|  | December 31,
| 2014 |  | 2013
| Carrying Amount |  | Fair Value |  | Carrying Amount |  | Fair Value
|  | (in thousands)
Assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed maturity securities—held to maturity |  | $ | 639,631 |  |  | $ | 664,371 |  |  | $ | 536,583 |  |  | $ | 561,179 |
Fixed maturity securities—available for sale |  |  | 331,242 |  |  |  | 331,242 |  |  |  | 237,877 |  |  |  | 237,877 |
Equity securities |  |  | 28 |  |  |  | 28 |  |  |  | 9,302 |  |  |  | 9,302 |
Cash and cash equivalents |  |  | 90,956 |  |  |  | 90,956 |  |  |  | 123,077 |  |  |  | 123,077 |
Short-term investments |  |  | 33,684 |  |  |  | 33,684 |  |  |  | 84,422 |  |  |  | 84,422 |
Other investments |  |  | 11,748 |  |  |  | 11,748 |  |  |  | 10,591 |  |  |  | 10,591 |
Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis | Assets and liabilities measured at fair value on a recurring basis as of December 31, 2014 and 2013 are as follows:
|  | December 31, 2014
|  | Level 1 Inputs |  | Level 2 Inputs |  | Level 3 Inputs |  | Total Fair Value
|  | (in thousands)
Financial instruments carried at fair value, classified as part of: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other investments |  | $ | — |  |  | $ | — |  |  | $ | 11,748 |  |  | $ | 11,748 |
Securities available for sale—equity: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Domestic common stock |  |  | 28 |  |  |  | — |  |  |  | — |  |  |  | 28 |
Securities available for sale—fixed maturity: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
States and political subdivisions |  |  | — |  |  |  | 157,374 |  |  |  | — |  |  |  | 157,374 |
U.S. agency-based mortgage-backed securities |  |  | — |  |  |  | 8,498 |  |  |  | — |  |  |  | 8,498 |
Corporate bonds |  |  | — |  |  |  | 165,370 |  |  |  | — |  |  |  | 165,370 |
Total available for sale—fixed maturity |  | $ | — |  |  | $ | 331,242 |  |  | $ | — |  |  | $ | 331,242 |
Total available for sale |  | $ | 28 |  |  | $ | 331,242 |  |  | $ | 11,748 |  |  | $ | 343,018 |
|  | December 31, 2013
|  | Level 1 Inputs |  | Level 2 Inputs |  | Level 3 Inputs |  | Total Fair Value
|  | (in thousands)
Financial instruments carried at fair value, classified as part of: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other investments |  | $ | — |  |  | $ | — |  |  | $ | 10,591 |  |  | $ | 10,591 |
Securities available for sale—equity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Domestic common stock |  |  | 9,302 |  |  |  | — |  |  |  | — |  |  |  | 9,302 |
Securities available for sale—fixed maturity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
States and political subdivisions |  |  | — |  |  |  | 150,375 |  |  |  | — |  |  |  | 150,375 |
U.S. agency-based mortgage-backed securities |  |  | — |  |  |  | 7,074 |  |  |  | — |  |  |  | 7,074 |
Corporate bonds |  |  | — |  |  |  | 80,428 |  |  |  | — |  |  |  | 80,428 |
Total available for sale—fixed maturity |  | $ | — |  |  | $ | 237,877 |  |  | $ | — |  |  | $ | 237,877 |
Total available for sale |  | $ | 9,302 |  |  | $ | 237,877 |  |  | $ | 10,591 |  |  | $ | 257,770 |
Schedule of Assets and Liabilities Measured at Amortized Cost | Assets and liabilities measured at amortized cost as of December 31, 2014 and 2013 are as follows:
|  | December 31, 2014
|  | Level 1 Inputs |  | Level 2 Inputs |  | Level 3 Inputs |  | Total Fair Value
|  | (in thousands)
Securities held-to-maturity—fixed maturity: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
States and political subdivisions |  | $ | — |  |  | $ | 405,665 |  |  | $ | — |  |  | $ | 405,665 |
Corporate bonds |  |  | — |  |  |  | 176,734 |  |  |  | — |  |  |  | 176,734 |
Commercial mortgage-backed securities |  |  | — |  |  |  | 48,529 |  |  |  | — |  |  |  | 48,529 |
U.S. agency-based mortgage-backed securities |  |  | — |  |  |  | 18,672 |  |  |  | — |  |  |  | 18,672 |
U.S. Treasury securities |  |  | 11,792 |  |  |  | — |  |  |  | — |  |  |  | 11,792 |
Asset-backed securities |  |  | — |  |  |  | 2,979 |  |  |  | — |  |  |  | 2,979 |
Total held-to-maturity |  | $ | 11,792 |  |  | $ | 652,579 |  |  | $ | — |  |  | $ | 664,371 |
|  | December 31, 2013
|  | Level 1 Inputs |  | Level 2 Inputs |  | Level 3 Inputs |  | Total Fair Value
|  | (in thousands)
Securities held-to-maturity—fixed maturity: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
States and political subdivisions |  | $ | — |  |  | $ | 399,155 |  |  | $ | — |  |  | $ | 399,155 |
Corporate bonds |  |  | — |  |  |  | 68,243 |  |  |  | — |  |  |  | 68,243 |
Commercial mortgage-backed securities |  |  | — |  |  |  | 54,244 |  |  |  | — |  |  |  | 54,244 |
U.S. agency-based mortgage-backed securities |  |  | — |  |  |  | 23,565 |  |  |  | — |  |  |  | 23,565 |
U.S. Treasury securities |  |  | 6,602 |  |  |  | — |  |  |  | — |  |  |  | 6,602 |
Obligations of the U.S. Government agencies |  |  | — |  |  |  | 5,914 |  |  |  | — |  |  |  | 5,914 |
Asset-backed securities |  |  | — |  |  |  | 3,456 |  |  |  | — |  |  |  | 3,456 |
Total held-to-maturity |  | $ | 6,602 |  |  | $ | 554,577 |  |  | $ | — |  |  | $ | 561,179 |
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.
|  | December 31, 2014 |  | December 31, 2013
|  | (in thousands)
Balance at beginning of year |  | $ | 10,591 |  |  | $ | — |
Purchases |  |  | — |  |  |  | 10,000 |
Total gains unrealized (included in earnings as part of net investment income) |  |  | 1,157 |  |  |  | 591 |
Balance at end of year |  | $ | 11,748 |  |  | $ | 10,591 |

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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 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 Reference 2: 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=36462937&loc=d3e19279-110258 + 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=36462937&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=35750535&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=35750535&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=35750535&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=36462937&loc=d3e19190-110258 + Details
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