Distribution of shares by sponsor.

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- Definition

Distribution of shares by sponsor subject to certain founder share restrictions.

+ References

No definition available.

+ Details

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- Definition

Free-traded of common shares.

+ References

No definition available.

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- Definition

Number of shares issued as charitable gift.

+ References

No definition available.

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- Definition

Warrant contractual term.

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No definition available.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21475-112644

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- Definition

Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

+ References

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- Definition

Value of input used to measure 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 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of unrealized gain (loss) on investment in marketable security.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(7)(c))
-URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227

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Marketable Securities - Additional Information (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2021 USD ($) $ / shares shares	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) $ / shares shares	Sep. 30, 2020 USD ($)	Sep. 14, 2021 shares
Marketable Securities [Line Items]
Unrealized (loss) gain on marketable securities \| $	$ (18,867,000)	$ 122,000	$ (18,665,000)	$ 15,000
IronNet [Member] \| Private Warrants [Member]
Marketable Securities [Line Items]
Distribution of shares by sponsor	2,065,000		2,065,000
Warrant exercisable to purchase common stock	1		1
Warrant exercise/ strike price \| $ / shares	$ 11.50		$ 11.50
Warrant contractual term			5 years
Free-traded of common shares	1,271,406		1,271,406
IronNet [Member] \| Expected Dividend Rate [Member] \| Private Warrants [Member]
Marketable Securities [Line Items]
Measurement input, dividend rate on warrants	0		0
IronNet [Member] \| Private Warrants [Member]
Marketable Securities [Line Items]
Distribution of shares by sponsor	2,065,000		2,065,000
IronNet [Member] \| Private Warrants [Member] \| LGL Systems Acquisition Holdings Company, LLC [Member]
Marketable Securities [Line Items]
Distribution of shares by sponsor					2,065,000
IronNet [Member] \| Common Stock [Member]
Marketable Securities [Line Items]
Distribution of shares by sponsor	1,250,000		1,250,000
Distribution of shares by sponsor subject to certain founder share restrictions	1,300,000		1,300,000
Distribution of shares by sponsor after charitable contribution	50,000		50,000
IronNet [Member] \| Common Stock [Member] \| LGL Systems Acquisition Holdings Company, LLC [Member]
Marketable Securities [Line Items]
Distribution of shares by sponsor					1,572,529
IronNet [Member] \| PIPE Related Common Shares [Member]
Marketable Securities [Line Items]
Distribution of shares by sponsor	272,529		272,529