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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] $ in Thousands | 12 Months Ended
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Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Increase in fair value of contingent consideration | $ 68 |
FeedbackNow [Member] |  |
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Increase in fair value of contingent consideration | $ 100 | $ 780
FeedbackNow [Member] | Discount Rate [Member] |  |
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Fair value of contingent consideration discount rate | 0.173 | 0.238
FeedbackNow [Member] | Revenue Volatility [Member] |  |
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] |  |
Fair value of contingent consideration discount rate | 0.266 | 0.219

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