For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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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 assets, excluding financial assets, that lack physical substance, having a limited useful life.

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The net realized gain (loss) on investments sold during the period, not including gains (losses) on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, which, for cash flow reporting, is a component of proceeds from investing activities.

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Concentration of Credit Risk and Fair Value of Financial Assets and Financial Liabilities - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Gain (loss) on sale of investments	$ 10,400	$ (1,300)	$ 7,600
Patent impairment	0	$ 2,427	13,228
Patents
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Patent impairment			$ 13,200
Patents \| Convida
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Patent impairment	$ 2,500
Four Largest Licensees \| Accounts Receivable \| Customer Concentration Risk
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Accounts receivable percentage (less than 10% for Customer E for year ended December 31, 2023 and 2022)	84.00%	76.00%
Sony Corporation of America \| Patents
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Fair value of patents		$ 30,100