The amount of excess separation costs.

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Amount of funds invested in mutual funds.

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Amount of income from mutual funds.

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Percentage of investment expense rate.

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Amount of monthly payment.

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Percentage of shares distribution under spinoff.

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Amount of salaries and benefits reimbursed.

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Amount of realized and unrealized gain (loss) on investment.

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Amount, before refund, of cash paid to foreign, federal, state, and local jurisdictions as income tax.

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Amount after accretion (amortization) of discount (premium), and investment expense, of interest income and dividend income on nonoperating securities.

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Note 7 - Related Party Transactions (Details Textual) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023	Oct. 07, 2022
Investment Income, Net	$ 538		$ 275	$ 1,037	$ 473
Gain (Loss) on Investments	$ (1)		$ 43	(4)	388
Income Taxes Paid				$ 76	$ 134
GAMCO Investors, Inc. [Member]
Investment Expense Rate	0.08%		0.08%	0.08%	0.14%
Funds Invested in Mutual Funds	$ 33,488			$ 33,488		$ 32,568
Income From Mutual Funds	441		$ 388	849	$ 822
Investment Income, Net			331		452
Gain (Loss) on Investments			57		370
MtronPTI [Member]
Percentage of Shares Distribution Under Spinoff							100.00%
Salaries and Benefits Reimbursed	27			53
Excess Separation Costs					28
MtronPTI [Member] \| Transitional Administrative and Management Services Agreement [Member]
Monthly Payment	4			4
Related Party Transaction, Amounts of Transaction	12		12	$ 24	24
MtronPTI [Member] \| Tax Indemnity and Sharing Agreement [Member]
Income Taxes Paid	$ 0	$ 0	$ 0		$ 0