Represents the amount of excess separation costs.

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- Definition

Fund management fee percent.

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Amount of membership interest.

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- Definition

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business.

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- Definition

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

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No definition available.

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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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No definition available.

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

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Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions.

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No definition available.

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Note E - Related Party Transactions (Details Textual) - USD ($)	3 Months Ended	6 Months Ended
	Mar. 31, 2023	Jun. 30, 2023	Dec. 31, 2022	Mar. 31, 2022
Subsidiary or Equity Method Investee, Cumulative Percentage Ownership after All Transactions	10.00%
Assets under Management, Carrying Amount		$ 31,980,000	$ 26,811,000
Fund Management Fee, Percent		0.08%
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	28,000
Mtron Industries Inc [Member]
Accounts Receivable, after Allowance for Credit Loss		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