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Investments (Realized and Unrealized Gains (Losses) on Equity Securities) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018
Gain (Loss) on Securities [Line Items] |  |  |  |
Unrealized gains (losses) recognized in income on equity securities on securities remaining in our portfolio at June 30, 2019 | $ 2,394 | $ 2,301 | $ 11,817 | $ (2,662)
Unrealized gains (losses) recognized in income on equity securities on securities sold in each respective period | (279) | (1,186) | 409 | (10,291)
Total unrealized gains (losses) recognized in income on equity securities | $ 2,115 | $ 1,115 | $ 12,226 | $ (12,953)

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- Definition The unrealized gains (losses) on equity securities sold during the period. + References No definition available. + Details
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- Definition Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117546-209714 + 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 The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of investments, not including unrealized gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, held at each balance sheet date and included in earnings for the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details
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