Note D - Marketable Securities - Details of Marketable Securities (Details) - Iron Net [Member] - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Fair value	$ 22	$ 16,585
Basis	33	21,297
Cumulative unrealized (loss) gain	(11)	(4,712)
Equity Funds And Other Securities [Member]
Fair value	22	16,539
Basis	33	17,024
Cumulative unrealized (loss) gain	$ (11)	(485)
Common Stock [Member]
Fair value		46
Basis		4,273
Cumulative unrealized (loss) gain		$ (4,227)

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(1)(b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482736/825-10-45-1A

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant