Investments in Securities and Fair Value (Schedule of Carrying Value and Fair Value of Financial Assets Disclosed) (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	$ 26,703	$ 20,838
Accrued interest and dividends	1,605	1,476
Equity securities, estimated fair value	46,361	41,481
Money market funds and U.S. Treasury bills	58,437	68,763
Assets, fair value disclosure	133,106	132,558
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	26,703	20,838
Accrued interest and dividends	1,605	1,476
Equity securities, estimated fair value	46,361	41,481
Money market funds and U.S. Treasury bills	58,437	68,763
Assets, fair value disclosure	133,106	132,558
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Accrued interest and dividends	0	0
Equity securities, estimated fair value	0	0
Money market funds and U.S. Treasury bills	0	0
Assets, fair value disclosure	0	0
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Accrued interest and dividends	0	0
Equity securities, estimated fair value	0	0
Money market funds and U.S. Treasury bills	0	0
Assets, fair value disclosure	$ 0	$ 0

Accrued dividends and interest, Estimated fair value

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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