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Marketable Securities - Details of Marketable Securities (Details) - IronNet [Member] - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Marketable Securities [Line Items] |  |
Fair Value | $ 16,167 | $ 5,791
Basis | 38,993 | 5,668
Cumulative Unrealized (Loss) Gain | (22,826) | 123
Put Options [Member] |  |
Marketable Securities [Line Items] |  |
Fair Value | 1,245 |
Basis | 489 |
Cumulative Unrealized (Loss) Gain | 756 |
Common Shares - Restricted [Member] |  |
Marketable Securities [Line Items] |  |
Fair Value | 4,734 |
Basis | 26,501 |
Cumulative Unrealized (Loss) Gain | (21,767) |
Common Shares - Unrestricted [Member] |  |
Marketable Securities [Line Items] |  |
Fair Value | 372 |
Basis | 2,195 |
Cumulative Unrealized (Loss) Gain | (1,823) |
IronNet Securities [Member] |  |
Marketable Securities [Line Items] |  |
Fair Value | 6,351 |
Basis | 29,185 |
Cumulative Unrealized (Loss) Gain | (22,834) |
Equity Funds and Other Securities [Member] |  |
Marketable Securities [Line Items] |  |
Fair Value | 9,816 | 5,791
Basis | 9,808 | 5,668
Cumulative Unrealized (Loss) Gain | $ 8 | $ 123

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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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=123594786&loc=SL75136599-209740 + Details
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