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)