Investments in Securities and Fair Value Investments in Securities (Schedule of Carrying Value and Fair Value of Financial Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Financial Assets
Cash	$ 24,654	$ 24,031
Accrued interest and dividends	1,469	978
Common stocks	39,893	37,212
Money market funds and U.S. Treasury bills	59,101	110,224
Assets, fair value disclosure	125,117	172,445
Level 1
Financial Assets
Cash	24,654	24,031
Accrued interest and dividends	1,469	978
Common stocks	39,893	37,212
Money market funds and U.S. Treasury bills	59,101	110,224
Assets, fair value disclosure	125,117	172,445
Level 2
Financial Assets
Cash	0	0
Accrued interest and dividends	0	0
Common stocks	0	0
Money market funds and U.S. Treasury bills	0	0
Assets, fair value disclosure	0	0
Level 3
Financial Assets
Cash	0	0
Accrued interest and dividends	0	0
Common stocks	0	0
Money market funds and U.S. Treasury bills	0	0
Assets, fair value disclosure	$ 0	$ 0

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Fair value portion of asset recognized for present right to economic benefit.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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

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Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current.

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