Fair Value Measurements - Fair Value Liabilities Measured on Recurring Basis (Detail) - Fair Value Measurements Recurring [Member] - Fair Value, Inputs, Level 3 [Member] $ in Thousands	9 Months Ended
Sep. 30, 2020 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Balance as of December 31, 2019	$ 320,100
Fair value adjustments	335,703
Payments	(189,903)
Balance as of September 30, 2020	$ 465,900

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.

No definition available.

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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=117815213&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

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- Definition

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Payment.

+ References

No definition available.

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