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Fund management fee percent.

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Amount of membership interest.

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The carrying amount of assets an investment adviser manages on behalf of investors.

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Amount of principal of investment owned.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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Amount of transactions with related party during the financial reporting period.

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Note E - Related Party Transactions (Details Textual) - USD ($)	1 Months Ended	3 Months Ended			9 Months Ended
	Jun. 30, 2023	Sep. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Assets under Management, Carrying Amount		$ 32,121,000			$ 32,121,000		$ 26,811,000
Fund Management Fee, Percent					0.08%
Net Income (Loss) Attributable to Noncontrolling Interest		22,000		$ 0	$ 22,000	$ 0
LGL System [Member]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	35.00%
Lynch Capital [Member]
Investment Owned, Balance, Principal Amount	$ 1,000,000
LGL System [Member] \| Investment, Affiliated Issuer [Member]
Membership Interest Amount	929,000
LGL System [Member] \| Investment, Unaffiliated Issuer [Member]
Membership Interest Amount	961,000
LGL System [Member]
Investment Owned, Balance, Principal Amount	1,000,000
LGL System [Member] \| Lynch Capital [Member]
Investment Owned, Balance, Principal Amount	$ 1,000,000
Mtron Industries Inc [Member] \| Spinoff [Member]
Excess Separation Costs			$ 28,000
Mtron Industries Inc [Member]
Accounts Receivable, after Allowance for Credit Loss		$ 0			0		6,000
Mtron Industries Inc [Member] \| Monthly Payment [Member]
Related Party Transaction, Amounts of Transaction					$ 4,000
Cash and Cash Equivalents [Member]
Assets under Management, Carrying Amount							10,295,000
Marketable Securities [Member]
Assets under Management, Carrying Amount							$ 16,516,000