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Fair Value Measurements - Summary of Changes in the Fair Value of Level 3 Contingent Consideration (Parenthetical) (Detail) - Level 3 [Member] - Contingent Consideration [Member] - FeedbackNow [Member] | Jun. 30, 2019
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Discount Rate [Member] |
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |
Fair value of contingent consideration dicount rate | 17.3
Revenue Volatility [Member] |
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |
Fair value of contingent consideration dicount rate | 26.6

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