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Investments - Additional Information (Detail) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2016 USD ($) Security | Sep. 30, 2015 USD ($) | Sep. 30, 2016 USD ($) Security | Sep. 30, 2015 USD ($) Security
Investments Schedule [Abstract] |  |  |  |
Individual fixed maturity held in unrealized loss position | Security | 73 |  | 73 |
Individual fixed maturity held in unrealized loss position longer than 12 months | Security | 19 |  | 19 |
Carrying value of investments | $ 12,200,000 |  | $ 12,200,000 |
Impairment losses recognized |  |  | 0 | $ 2,700,000
Net realized gains (losses) on investments | $ 181,000 | $ 40,000 | $ 974,000 | $ (2,518,000)
Number of fixed maturity securities to be deemed other-than-temporarily impaired | Security |  |  |  | 4
Net realized gain(loss)outside OTTI |  |  |  | $ 200,000

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- Definition Number of individual fixed maturity securities in unrealized loss position. + References No definition available. + Details
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- Definition Number of individual investment securities in unrealized loss position greater than twelve months. + References No definition available. + 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=66902209&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 This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(3)(d)) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(9)(a)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(7)(c)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(13)(g)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 + Details
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