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Schedule of Other Than Temporary Impairments on Investments (Detail) - USD ($) $ in Thousands | 9 Months Ended
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Sep. 30, 2020 | Sep. 30, 2019
Investments Debt And Equity Securities [Abstract] |  |
OTTI losses, gross | $ 0 | $ (1,897)
Portion of loss recognized in other comprehensive income (pre-tax) | 0 | 0
Net impairment losses on fixed maturities recognized in earnings | $ 0 | $ (1,897)

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- Definition Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings and other comprehensive loss (OCI). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 8A -URI http://asc.fasb.org/extlink&oid=121553693&loc=SL6284422-111562 + Details
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- Definition Amount, before tax, of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in other comprehensive income (OCI). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669646-108580 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 8A -URI http://asc.fasb.org/extlink&oid=121553693&loc=SL6284422-111562 + Details
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