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Marketable Securities - Details of Marketable Securities (Details) - IronNet [Member] $ in Thousands | Sep. 30, 2021 USD ($)
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Marketable Securities [Line Items] |
Fair Value | $ 50,828
Basis | 69,371
Cumulative Unrealized (Loss) Gain | (18,543)
Private Warrants [Member] |
Marketable Securities [Line Items] |
Fair Value | 20,374
Basis | 31,504
Cumulative Unrealized (Loss) Gain | (11,130)
Restricted Common Shares [Member] |
Marketable Securities [Line Items] |
Fair Value | 19,390
Basis | 26,501
Cumulative Unrealized (Loss) Gain | (7,111)
PIPE Related Common Shares [Member] |
Marketable Securities [Line Items] |
Fair Value | 4,647
Basis | 6,185
Cumulative Unrealized (Loss) Gain | (1,538)
IronNet Securities [Member] |
Marketable Securities [Line Items] |
Fair Value | 44,411
Basis | 64,190
Cumulative Unrealized (Loss) Gain | (19,779)
Equity Funds and Other Securities [Member] |
Marketable Securities [Line Items] |
Fair Value | 6,417
Basis | 5,181
Cumulative Unrealized (Loss) Gain | $ 1,236

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