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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 ($) |  | 9 Months Ended |
--- | --- | --- | ---
Jul. 06, 2018 | Sep. 30, 2020 | Dec. 31, 2019
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 |  |
Contingent consideration payable period | 2 years |  |
Fair value of contingent consideration, payment period |  | 2020-10 |
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 |  | $ 2,700,000 | $ 2,500,000

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- Definition For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479 + Details
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