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Marketable Securities - Details of Marketable Securities (Details) - IronNet [Member] - USD ($) $ in Thousands | Sep. 30, 2022 | Dec. 31, 2021
--- | --- | ---
Marketable Securities [Line Items] |  |
Fair Value | $ 17,070 | $ 16,167
Basis | 44,457 | 38,993
Cumulative Unrealized (Loss) Gain | (27,387) | (22,826)
Put Options [Member] |  |
Marketable Securities [Line Items] |  |
Fair Value | 26 | 1,245
Basis | 13 | 489
Cumulative Unrealized (Loss) Gain | 13 | 756
IronNet Securities [Member] |  |
Marketable Securities [Line Items] |  |
Fair Value | 914 | 6,351
Basis | 27,649 | 29,185
Cumulative Unrealized (Loss) Gain | (26,735) | (22,834)
Equity Funds and Other Securities [Member] |  |
Marketable Securities [Line Items] |  |
Fair Value | 16,156 | 9,816
Basis | 16,808 | 9,808
Cumulative Unrealized (Loss) Gain | (652) | 8
Shares of Common Stock [Member] |  |
Marketable Securities [Line Items] |  |
Fair Value | 888 | 5,106
Basis | 27,636 | 28,696
Cumulative Unrealized (Loss) Gain | $ (26,748) | $ (23,590)

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