Marketable Securities: Available-For-Sale Debt Securities - Schedule of Number of Securities Held by Company, Aggregate Fair Value and Unrealized Loss Position (Details) $ in Thousands	Dec. 31, 2025 USD ($) security	Dec. 31, 2024 USD ($) security
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Number of securities held \| security	4	56
Gross unrealized losses	$ (2)	$ (343)
Fair market value of investments in an unrealized loss position	9,454	293,234
Debt Securities, Available-for-Sale
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Gross unrealized losses	$ (500)	$ (300)
Debt Securities, Available-for-Sale \| Commercial paper
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Number of securities held \| security	2	3
Gross unrealized losses	$ (1)	$ (6)
Fair market value of investments in an unrealized loss position	$ 2,454	$ 8,944
Debt Securities, Available-for-Sale \| Corporate debt securities
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Number of securities held \| security	2	41
Gross unrealized losses	$ (1)	$ (264)
Fair market value of investments in an unrealized loss position	$ 7,000	$ 133,078
Debt Securities, Available-for-Sale \| United Kingdom Government Securities
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Number of securities held \| security		8
Gross unrealized losses		$ (69)
Fair market value of investments in an unrealized loss position		$ 141,307
Debt Securities, Available-for-Sale \| US Treasury Bills
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Number of securities held \| security		4
Gross unrealized losses		$ (4)
Fair market value of investments in an unrealized loss position		$ 9,905

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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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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