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Investments - Equity Securities (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Dec. 31, 2018
Equity Securities, FV-NI, Gain (Loss) [Abstract] |  |  |
Cost | $ 4,016 |  | $ 3,993
Gross Gains | 60 |  | 11
Gross Losses | (19) |  | (72)
Fair Value | 4,057 |  | $ 3,932
Unrealized Gain (Loss) on Equity Securities [Abstract] |  |  |
Recognized net gains (losses) on equity securities still held | $ 100 | $ (100) |

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- Definition Equity Securities, FV-NI, Gain (Loss) [Abstract] + References No definition available. + Details
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- Definition Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References No definition available. + Details
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- Definition Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value. + References No definition available. + Details
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- Definition Amount of unrealized gain on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + 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 No definition available. + Details
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- Definition Amount of unrealized loss on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References No definition available. + Details
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