Fair Value Measurements (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021	Oct. 07, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	$ 72,535	$ 72,535		$ 229,200
Unrealized gain	(27,300)	(18,400)
Contingent consideration	3,000	3,000
Financial liability value	3,047	3,047		5,775
Contingent consideration payments		(2,919)	$ (5,800)
4.625% Senior Notes \| Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of debt instruments	$ 482,500	$ 482,500		$ 659,900
Stated interest rate	4.625%	4.625%			4.625%

Amount of liability recognized arising from contingent consideration in a business combination.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current.

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Amount of unrealized gain (loss) on investment.

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