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Fair Value Measurements - Marketable Securities (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 USD ($)
Changes In Marketable Securities [Roll Forward] |
Balance at December 31, 2019 | $ 11
Mutual funds purchases | 0
Mutual funds sales | (11)
Realized gains (losses) | 0
Balance at December 31, 2020 | $ 0

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- Definition Amount of investment in marketable security. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.4) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 + Details
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