Fair Value Measurements - Schedule of Reconciliation of CVR Liability (Detail) - Level 3 Inputs [Member] - Contingent Value Right [Member] $ in Millions |
12 Months Ended | |||
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Dec. 31, 2018
USD ($)
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| Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] | ||||
| Fair value as of December 31, 2017 | $ 6.9 | |||
| Net unrealized loss | 8.8 | [1] | ||
| Fair value as of December 31, 2018 | $ 15.7 | |||
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- Definition Non transferable contractual contingent value right agreement fair value. 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. No definition available.
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- Definition Amount of gain (loss) recognized on the income statement for 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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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