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Fair Value of Financial Instruments - Narrative (Details) - USD ($) | 3 Months Ended
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Mar. 31, 2021 | Mar. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Percentage of level 3 invested assets in total investment portfolio | 5.10% |
Net investment gains (losses) included in net income related to financial assets | $ 0 | $ 0
Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Net investment gains (losses) included in net income related to financial assets | $ 0 | 0
Net realized investment losses |  | $ 5,000,000.0

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- Definition Percentage of invested assets in the total investment portfolio in Level 3 carried at fair value on a recurring basis. + References No definition available. + Details
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- Definition 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 Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + 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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