Amount of non-cash accretion & amortization of short-term investments.

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The number of federally insured financial institutions.

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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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No definition available.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value.

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Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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The charge against earnings resulting from the aggregate write down of tangible assets from their carrying value to their fair value.

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Summary of Significant Accounting Policies (Details)	3 Months Ended		12 Months Ended
Summary of Significant Accounting Policies (Details)	Mar. 31, 2024 USD ($) segment Institution	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)
Summary of Significant Accounting Policies
Non-cash accretion & amortization of short-term investments	$ (2,055,000)	$ (2,341,000)	$ 2,341,000
Segment Information
Number of operating segments \| segment	1
Number of reporting segments \| segment	1
Off Balance Sheet Risk and Concentrations of Credit Risk
Number of federally insured financial institutions \| Institution	2
Impairment of Long-Lived Assets
Tangible asset impairment charges	$ 0	0
Patent Costs
Patent costs	34,382,000	24,634,000
Accounts Receivable, net
Revenue	$ 25,967,000	$ 11,469,000
Customer concentration risk \| Customer one \| Revenue benchmark
Off Balance Sheet Risk and Concentrations of Credit Risk
Percentage of revenue generated from customer	74.00%	83.00%
Accounts Receivable, net
Accounts receivables	$ 72		$ 67
Product revenue
Accounts Receivable, net
Revenue	$ 25,967,000	$ 11,469,000