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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Value of input used to measure investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

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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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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Basis of Presentation and Summary of Significant Accounting Policies - Narrative (Details)	12 Months Ended
	Dec. 31, 2023 USD ($) segment	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2007 $ / shares	Jan. 31, 2010 right
Basis of Presentation
Number of reportable segment \| segment	1
Increase (decrease) of allowance for credit loss	$ 200,000	$ (300,000)	$ 10,000.00
Write-downs related to obsolete inventory	200,000	1,100,000	$ 0
Inventory	23,969,000	13,294,000
Revenue recognized	$ 100,000	400,000
Dividend declared (in USD per share) \| $ / shares				$ 2.50
Dividend yield
Basis of Presentation
Measurement input (as a percent)	0
PSUs
Basis of Presentation
Award vesting period (in years)	3 years
Employee Stock Option \| 2002 Stock Incentive Plan
Basis of Presentation
Award expiration period (in years)	10 years
Employee Stock Option \| 2002 Stock Incentive Plan \| Vest 1/8 on the six month anniversary of the date of grant
Basis of Presentation
Award vesting period (in years)	6 months
Award vesting right (as a percent)	12.50%
Employee Stock Option \| 2002 Stock Incentive Plan \| Vest 1/48 each month for forty-two months
Basis of Presentation
Award vesting period (in years)	42 months
Award vesting right (as a percent)	2.08%
RSUs and PSUs
Basis of Presentation
Award vesting period (in years)	3 years
Metabasis Therapeutics
Basis of Presentation
Number of contingent value rights \| right					4
Minimum
Basis of Presentation
Property and equipment, useful life (in years)	1 year
Minimum \| PSUs
Basis of Presentation
Award vesting right (as a percent)	0.00%
Maximum
Basis of Presentation
Property and equipment, useful life (in years)	9 years
Maximum \| PSUs
Basis of Presentation
Award vesting right (as a percent)	200.00%
Captisol
Basis of Presentation
Inventory	$ 4,600,000	$ 5,900,000