Fair Value Measurements - Stock Option Rollforward (Details) - Stock Option Liability - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 0	$ 43,026
Exercise of stock options	0	(224)
Change in fair value	0	(9,087)
Amortization of grant date fair value	0	3,603
Ending balance	$ 0	$ 37,318

Fair Value, Measurement With Unobservable Inputs Reconciliation, Recurring Basis, Liability, Amortization During Period

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- Definition

Fair Value, Measurement With Unobservable Inputs Reconciliation, Recurring Basis, Liability, Exercise Of Stock Options In Period

+ References

No definition available.

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- Definition

Fair Value, Measurement With Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included In Earnings, Excluding Amortization

+ References

No definition available.

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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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

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=117815213&loc=d3e19207-110258

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