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Fair Value of Financial Instruments - Narrative (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 USD ($) security | Dec. 31, 2019 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Percentage of investment portfolio fair value pricing services or index price | 91.90% | 94.10%
Net investment losses included in net income related to financial assets | $ | $ 277 | $ 1,067
Minimum |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Number of hard-to-value fixed maturity securities | security | 100 |
Maximum |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Number of hard-to-value fixed maturity securities | security | 150 |
Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Percentage of invested assets in total investment portfolio Level 3 recurring | 5.30% |
Net investment gain (loss) | $ | $ (11,500) | $ (12,600)

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- Definition Net Increase or Decrease in the fair value of the embedded derivative or group of embedded derivatives included in earnings in the period. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 15 -URI http://asc.fasb.org/subtopic&trid=2229187 + Details
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- Definition Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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