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Fair Value Measurements - Summary of Company's Fair Value Hierarchy for its Financial Assets and Liabilities (Parenthetical) (Detail) - FeedbackNow [Member] - USD ($) | Jul. 06, 2018 | Jun. 30, 2020 | Dec. 31, 2019
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Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |
Maximum contingent consideration payable based on the financial performance of acquired company | $ 4,200,000 | $ 2,600,000 |
Contingent consideration payable period | 2 years |  |
Accrued Expenses and Other Current Liabilities [Member] |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |
Fair value of contingent consideration to be paid |  | $ 2,600,000 | $ 2,500,000

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