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Investments - Additional Information (Detail) (USD $) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2013 Securities Individual Equity | Dec. 31, 2012
Investment [Line Items] |  |
Short term debt | $ 84,422,000 | $ 68,924,000
Carrying value of investments | 10,600,000 |
Held to maturity investments | 16,300,000 |
Individual fixed maturity held in unrealized loss position | 182 |
Equity securities held in unrealized loss position | 8 |
Individual fixed maturity held in unrealized loss position | 18 |
Number of equity securities to be deemed other-than-temporarily impaired | 4 |
Equity securities [Member] |  |
Investment [Line Items] |  |
Impairment losses recognized | 2,200,000 |
Corporate bonds [Member] |  |
Investment [Line Items] |  |
Short term debt | 82,700,000 | 63,500,000
Certificates of deposit [Member] |  |
Investment [Line Items] |  |
Short term debt | 900,000 | 900,000
Municipal securities [Member] |  |
Investment [Line Items] |  |
Short term debt | $ 800,000 | $ 4,500,000

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- Definition Carrying amount of cash and investment securities on deposit with state regulatory authorities in connection with capital requirements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 320 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=28366721&loc=d3e22002-158495 + Details
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- Definition The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e25351-111560 + Details
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- Definition Investments which are intended to be sold in the short term (usually less than one year or the normal operating cycle, whichever is longer) including trading securities, available-for-sale securities, held-to-maturity securities, and other short-term investments not otherwise listed in the existing taxonomy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph g -Article 7 + Details
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