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Marketable Securities - Narrative (Details) - USD ($) | 3 Months Ended
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Mar. 31, 2021 | Mar. 31, 2020
Investments, Debt and Equity Securities [Abstract] |  |
Marketable securities, realized loss | $ 0 | $ 0
Marketable securities, realized gain | $ 0 | $ 0

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- Definition Marketable Securities, Realized Gain + References No definition available. + Details
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- Definition Marketable Securities, Realized Loss + References No definition available. + Details
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- References No definition available. + Details
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