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Fair Value Measurements (Narrative) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)	Oct. 07, 2020	Nov. 15, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	$ 16,404		$ 27,109
Unrealized losses	$ (10,700)	$ (20,300)
Measurement Input, Discount Rate \| Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale, measurement input	0.13		0.13
Measurement Input, Discount Rate \| Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale, measurement input	0.14		0.14
Measurement Input, Conversion Term \| Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale, term	1 year		1 year
Measurement Input, Conversion Term \| Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale, term	3 years		3 years
4.625% Senior Notes \| Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate				4.625%
1.75% Convertible Notes \| Convertible Debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate					1.75%