Fair Value Measurements (Schedule of Assets and Liabilities Measured at Fair Value) (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents	$ 435	$ 417
Related party note receivable		5,179
Investment in MiNK Therapeutics, Inc.	22,927	24,277
Long-term investments	1,088	1,303
Total	24,450	31,176
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents	435	417
Related party note receivable		0
Investment in MiNK Therapeutics, Inc.	22,927	24,277
Long-term investments	1,088	1,303
Total	24,450	25,997
Significant Other Observable Inputs (Level 2) [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents	0	0
Related party note receivable		5,179
Investment in MiNK Therapeutics, Inc.	0	0
Long-term investments	0	0
Total	0	5,179
Significant Unobservable Inputs (Level 3) [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents	0	0
Related party note receivable		0
Investment in MiNK Therapeutics, Inc.	0
Long-term investments	0
Total	$ 0	$ 0

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- Definition

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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Fair value portion of investments accounted under the equity method.

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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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Fair value portion of an agreement for an unconditional promise by the maker to pay the holder a definite sum of money at a future date.

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