Fair Value Measurements (Schedule of Liabilities Measured at Fair Value Using Significant Unobservable Inputs) (Details) - Significant Unobservable Inputs (Level 3) [Member] $ in Thousands	9 Months Ended
Sep. 30, 2021 USD ($)
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Balance, beginning of period	$ 10,208
Achievement of 4-AB contingent milestones	(20,000)
Balance, end of period	3,739
Contingent Purchase Price [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Change in fair value of considerations during the period	$ 13,531

Fair value measurement with unobservable inputs reconciliation recurring basis liability contingent milestones.

No definition available.

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Amount of increase (decrease) 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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- Definition

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.

+ References

+ Details

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